# Testing Methodologies Standards for Readability
This document outlines the testing methodologies standards for the Readability project. It provides guidelines for writing effective unit, integration, and end-to-end tests, ensuring the reliability, maintainability, and performance of Readability applications. This document is intended to be used by developers and as a context for AI coding assistants.
## 1. General Testing Principles
### 1.1 Write Testable Code
**Do This:** Design code with testability in mind from the beginning. Use dependency injection, modularity, and clear separation of concerns.
**Don't Do This:** Write monolithic, tightly coupled code that is difficult to isolate and test.
**Why:** Testable code is easier to understand, maintain, and debug. It allows for better isolation of issues, making it simpler to pinpoint the root cause of bugs.
**Example:**
"""python
# Bad: Tightly coupled code
class DataProcessor:
def __init__(self):
self.db_connection = DatabaseConnection() # Hardcoded dependency
def process_data(self, data):
self.db_connection.insert(data)
# ... more processing logic ...
# Good: Dependency Injection
class DataProcessor:
def __init__(self, db_connection):
self.db_connection = db_connection
def process_data(self, data):
self.db_connection.insert(data)
# ... more processing logic ...
class DatabaseConnection:
def insert(self, data):
print(f"Inserting {data} into the database") # Mock implementation
# Example Usage in test:
mock_db = DatabaseConnection() #can mock methods here
processor = DataProcessor(mock_db)
processor.process_data("test_data")
"""
### 1.2 Test Early and Often
**Do This:** Integrate testing into your development workflow. Write tests before or alongside the code being developed (TDD/BDD).
**Don't Do This:** Defer testing until the end of the development cycle.
**Why:** Early testing helps identify bugs sooner, reducing the cost and effort required to fix them. It also promotes better design and clearer understanding of requirements.
### 1.3 Aim for High Code Coverage
**Do This:** Ensure that your tests cover a large portion of your codebase. Use code coverage tools to identify areas that are not adequately tested.
**Don't Do This:** Neglect code coverage, assuming that testing a few key areas is sufficient.
**Why:** High code coverage increases confidence in the correctness of your code. However, coverage should not be the only metric – the quality and effectiveness of the tests are just as important. Focus on covering edge cases, boundary conditions, and complex logic.
### 1.4 Write Clear and Concise Tests
**Do This:** Tests should be easily understandable, well-organized, and focused on a specific aspect of the code. Use descriptive names for test functions and variables.
**Don't Do This:** Write complex, convoluted tests that are difficult to understand or maintain. Avoid long, multi-purpose test functions.
**Why:** Clear tests are easier to debug and maintain. They also serve as documentation for the code being tested.
### 1.5 Follow the Arrange-Act-Assert (AAA) Pattern
**Do This:** Structure your tests according to the Arrange-Act-Assert pattern.
**Don't Do This:** Mix the arrange, act, and assert steps, or omit any of these steps.
**Why:** The AAA pattern provides a clear structure for tests, making them easier to read and maintain. It ensures that each test is focused and well-defined.
* **Arrange:** Set up the test environment, including creating objects, initializing variables, and mocking dependencies.
* **Act:** Execute the code under test.
* **Assert:** Verify the expected outcome.
**Example:**
"""python
import unittest
class StringFormatter:
def capitalize(self, text):
return text.capitalize()
class TestStringFormatter(unittest.TestCase):
def test_capitalize_empty_string(self):
# Arrange
formatter = StringFormatter()
input_string = ""
# Act
result = formatter.capitalize(input_string)
# Assert
self.assertEqual(result, "")
def test_capitalize_single_word(self):
# Arrange
formatter = StringFormatter()
input_string = "hello"
# Act
result = formatter.capitalize(input_string)
# Assert
self.assertEqual(result, "Hello")
"""
## 2. Unit Testing
### 2.1 Focus on Individual Units
**Do This:** Unit tests should focus on testing individual functions, classes, or modules in isolation. Use mocks and stubs to isolate the unit under test from its dependencies.
**Don't Do This:** Write unit tests that depend on external resources, databases, or other services.
**Why:** Unit testing helps identify defects in specific components, making it easier to pinpoint the source of errors. It also allows for faster test execution.
### 2.2 Utilize Mocking and Stubbing
**Do This:** Use mocking and stubbing to replace external dependencies with controlled test doubles. This allows you to isolate the unit under test and simulate various scenarios.
**Don't Do This:** Avoid mocking or stubbing when testing units that interact with external dependencies.
**Why:** Mocking and stubbing provide a deterministic test environment by eliminating the variability introduced by external dependencies. This makes tests more reliable and easier to reproduce.
**Example (Python with "unittest.mock"):**
"""python
import unittest
from unittest.mock import patch
class ExternalService:
def get_data(self):
# Imagine this fetches data from an external source.
raise NotImplementedError
class DataProcessor:
def __init__(self, service):
self.service = service
def process_data(self):
data = self.service.get_data()
return data.upper() # Example processing
class TestDataProcessor(unittest.TestCase):
@patch('your_module.ExternalService') # Assumes ExternalService is defined in your_module.py
def test_process_data(self, MockExternalService):
# Arrange
mock_service = MockExternalService.return_value
mock_service.get_data.return_value = "test data"
processor = DataProcessor(mock_service)
# Act
result = processor.process_data()
# Assert
self.assertEqual(result, "TEST DATA")
mock_service.get_data.assert_called_once()
"""
### 2.3 Test Edge Cases and Boundary Conditions
**Do This:** Thoroughly test edge cases, boundary conditions, and error handling to ensure that the code behaves correctly under unexpected circumstances.
**Don't Do This:** Focus only on happy path scenarios, neglecting to test error handling or boundary conditions.
**Why:** Edge cases and boundary conditions are often the source of bugs. Testing these scenarios helps prevent unexpected behavior in production.
### 2.4 Write Assertions That Provide Meaningful Messages
**Do This:** Write descriptive assertion messages that provide specific information about the failure.
**Don't Do This:** Use generic assertion messages that do not provide enough context for debugging.
**Why:** Meaningful assertion messages make it easier to understand the nature of a test failure and to pinpoint the root cause of the problem.
## 3. Integration Testing
### 3.1 Focus on Interactions Between Components
**Do This:** Integration tests should focus on verifying the interactions between different components or modules within the system.. Mimic real-world workflows, rather than purely functional interactions between classes.
**Don't Do This:** Overlap the scopes between unit and integration tests. Don't test the isolated functionalities, but instead aim for flows that involves several components.
**Why:** Integration testing helps identify issues that arise when different parts of the system are integrated. It ensures that components work together correctly.
### 3.2 Use Real Dependencies Where Appropriate
**Do This:** Use real dependencies (e.g., databases, message queues) in integration tests when it is practical and feasible. Consider using test containers or in-memory databases for faster and more reliable testing.
**Don't Do This:** Mock all dependencies in integration tests. If all dependencies are mocked, it acts more like a unit tests set, reducing the value of the tests.
**Why:** Using real dependencies in integration tests provides a more realistic testing environment. Testing against real-world data stores catches issues with data models, serialization, and database interactions.
### 3.3 Test Data Integrity
**Do This:** Verify that data is correctly passed between components and that data integrity is maintained throughout the integration.
**Don't Do This:** Neglect to validate the consistency and accuracy of data within data stores.
**Why:** Integration tests are critical for ensuring that data is not corrupted or lost as it moves between different components. Data integrity is essential for the proper functioning of the system.
**Example (Testing API endpoint integration):**
"""python
import unittest
import requests
import json
class TestAPIIntegration(unittest.TestCase):
BASE_URL = "http://localhost:8000" # Replace with your API base URL
def test_create_and_retrieve_resource(self):
# Arrange
resource_data = {"name": "Test Resource", "value": 123}
create_url = f"{self.BASE_URL}/resources"
get_url = f"{self.BASE_URL}/resources/1" # Assumes ID 1 will be created
# Act - Create
create_response = requests.post(create_url, json=resource_data)
self.assertEqual(create_response.status_code, 201) # Check creation status
# Act - Retrieve
get_response = requests.get(get_url)
self.assertEqual(get_response.status_code, 200) # Check success
# Assert
retrieved_data = get_response.json()
self.assertEqual(retrieved_data["name"], resource_data["name"])
self.assertEqual(retrieved_data["value"], resource_data["value"])
def test_error_handling(self):
# Arrange
invalid_data = {"invalid_key": True}
url = f"{self.BASE_URL}/resources"
# Act
response = requests.post(url, json=invalid_data)
# Assert
self.assertEqual(response.status_code, 400) # Ensure correct error code
"""
### 3.4 Address Asynchronous and Event-Driven Systems Carefully
**Do This:** Acknowledge the complexities of testing integrations involving async processes or event-driven architectures by building explicit waits or retries into the test suite.
**Don't Do This:** Assume synchronous behavior for the entire integration testing suit.
**Why:** Asynchronous tests often suffer from timing related issues, making the results unreliable.
## 4. End-to-End (E2E) Testing
### 4.1 Simulate Real User Scenarios
**Do This:** End-to-end tests should simulate real user scenarios, covering the entire application workflow from start to finish.
**Don't Do This:** Break E2E workflows into smaller, isolated components.
**Why:** End-to-end testing verifies that the entire system works correctly from the user's perspective. This is crucial for ensuring that the application meets the user's needs.
### 4.2 Test Against Realistic Environments
**Do This:** Run end-to-end tests against environments that closely resemble production. Use real or near-real data.
**Don't Do This:** Run E2E against drastically different, basic environments that do not mirror prod settings.
**Why:** Testing against realistic environments increases confidence that the application will perform as expected in production.
### 4.3 Automate UI Interactions
**Do This:** Use automation frameworks (e.g., Selenium, Cypress, Playwright) to automate user interface interactions in end-to-end tests.
**Don't Do This:** Perform end-to-end tests manually.
**Why:** Automated UI testing is more efficient and reliable than manual testing. It allows for faster test execution and better coverage of the application's functionality.
**Example (Playwright):**
"""python
from playwright.sync_api import sync_playwright
import unittest
class E2ETests(unittest.TestCase):
def setUp(self):
self.playwright = sync_playwright().start()
self.browser = self.playwright.chromium.launch() # or firefox, webkit
self.context = self.browser.new_context()
self.page = self.context.new_page()
self.page.goto("http://localhost:3000") # Replace with app URL
def tearDown(self):
self.page.close()
self.context.close()
self.browser.close()
self.playwright.stop()
def test_login_flow(self):
# Arrange (Assuming a simple login form)
self.page.fill("input[name='username']", "testuser")
self.page.fill("input[name='password']", "testpassword")
# Act
self.page.click("button[type='submit']") # Assumes submit button
# Assert (Check for successful login - e.g., redirect)
self.page.wait_for_url("http://localhost:3000/dashboard", timeout=5000) # Adjust URL/timeout
self.assertEqual(self.page.url, "http://localhost:3000/dashboard")
def test_form_submission(self):
# Arrange
self.page.fill("input[name='name']", "John Doe")
self.page.select_option("select[name='age']", "30")
# Act
with self.page.expect_response("**/submit-form"): # Wait for submission
self.page.click("text=Submit")
# Assert
# Example assertions - adapt to your specific needs
self.assertEqual(self.page.inner_text("div#success-message"), "Form submitted successfully!")
"""
### 4.4 Include UI and API testing.
**Do This:** Make a balance between UI-driven tests and API-driven tests. If a given feature is best tested through API calls, prefer it.
**Don't Do This:** Think only of UI actions whenever doing E2E
**Why:** API E2E runs faster and are more stable.
## 5. Performance Testing
### 5.1 Identify Performance Bottlenecks
**Do This:** Performance tests should identify performance bottlenecks and areas for optimization.
**Don't Do This:** Neglect performance during the development process.
**Why:** Performance testing helps ensure that the application can handle the expected load and provide a good user experience.
### 5.2 Use Load Testing Tools
**Do This:** Use load testing tools (e.g., JMeter, Gatling, Locust) to simulate realistic user traffic and measure application performance under load.
**Don't Do This:** Rely on anecdotal experience or basic spot checks.
**Why:** Load testing helps identify performance issues that may not be apparent under normal usage conditions.
### 5.3 Establish Performance Baselines
**Do This:** Establish performance baselines and track performance metrics over time.
**Don't Do This:** Only perform testing on specific, major modifications. Establish a periodic performance measurement.
**Why:** Tracking performance metrics helps identify performance regressions and ensure that the application continues to meet performance requirements.
## 6. Security Testing
### 6.1 Perform Regular Security Audits
**Do This:** Perform regular security audits (e.g., using automated vulnerability scanners) to identify and address potential security vulnerabilities.
**Don't Do This:** View security as an afterthought.
**Why:** Security testing helps protect the application and its users from security threats.
### 6.2 Test for Common Vulnerabilities
**Do This:** Test for common vulnerabilities such as SQL injection, cross-site scripting (XSS), and cross-site request forgery (CSRF).
**Don't Do This:** Neglect to test the various dimensions of potential threats.
**Why:** Addressing common vulnerabilities helps prevent security breaches and protect sensitive data.
### 6.3 Follow Secure Coding Practices
**Do This:** Adhere to secure coding practices to minimize the risk of introducing security vulnerabilities.
**Don't Do This:** Ignore patterns that favors security.
**Why:** Secure coding practices are essential for building secure applications.
## 7. Continuous Integration and Continuous Deployment (CI/CD)
### 7.1 Integrate Testing into the CI/CD Pipeline
**Do This:** Integrate all types of testing (unit, integration, end-to-end, performance, security) into the CI/CD pipeline.
**Don't Do This:** Keep testing aside of the deployment workflow.
**Why:** CI/CD automates the testing and deployment process, ensuring that changes are thoroughly tested before being released to production.
### 7.2 Automate Test Execution
**Do This:** Automate the execution of all tests as part of the CI/CD pipeline.
**Don't Do This:** Allow manual steps during automated builds.
**Why:** Automated test execution reduces the risk of human error and ensures that tests are run consistently.
### 7.3 Monitor Test Results
**Do This:** Monitor test results and quickly address any failures.
**Don't Do This:** Ignore frequent warnings and failures in the CI/CD suite.
**Why:** Monitoring test results helps ensure that the application remains stable and that new changes do not introduce regressions.
## 8. Advanced Testing Techniques
### 8.1 Property-Based Testing
**Do This:** Consider property-based testing to generate a wide range of inputs and verify that certain properties hold true for the code under test.
**Don't Do This:** Limit the scope of the tests to isolated and deterministic input.
**Why:** Property-based testing can uncover edge cases and boundary conditions that may not be caught by traditional example-based testing.
(Check libraries such as Hypothesis, jqwik, fast-check)
### 8.2 Mutation Testing
**Do This:** Use mutation testing tools to assess the effectiveness of the tests. Mutation testing involves introducing small changes (mutations) to the code and verifying that the tests catch these changes.
**Don't Do This:** Assume that high coverage correlates directly with the quality of testing.
**Why:** Mutation testing provides a metric for the strength of the test suite beyond coverage metrics.
danielsogl
Created Mar 6, 2025
This guide explains how to effectively use .clinerules
with Cline, the AI-powered coding assistant.
The .clinerules
file is a powerful configuration file that helps Cline understand your project's requirements, coding standards, and constraints. When placed in your project's root directory, it automatically guides Cline's behavior and ensures consistency across your codebase.
Place the .clinerules
file in your project's root directory. Cline automatically detects and follows these rules for all files within the project.
# Project Overview project: name: 'Your Project Name' description: 'Brief project description' stack: - technology: 'Framework/Language' version: 'X.Y.Z' - technology: 'Database' version: 'X.Y.Z'
# Code Standards standards: style: - 'Use consistent indentation (2 spaces)' - 'Follow language-specific naming conventions' documentation: - 'Include JSDoc comments for all functions' - 'Maintain up-to-date README files' testing: - 'Write unit tests for all new features' - 'Maintain minimum 80% code coverage'
# Security Guidelines security: authentication: - 'Implement proper token validation' - 'Use environment variables for secrets' dataProtection: - 'Sanitize all user inputs' - 'Implement proper error handling'
Be Specific
Maintain Organization
Regular Updates
# Common Patterns Example patterns: components: - pattern: 'Use functional components by default' - pattern: 'Implement error boundaries for component trees' stateManagement: - pattern: 'Use React Query for server state' - pattern: 'Implement proper loading states'
Commit the Rules
.clinerules
in version controlTeam Collaboration
Rules Not Being Applied
Conflicting Rules
Performance Considerations
# Basic .clinerules Example project: name: 'Web Application' type: 'Next.js Frontend' standards: - 'Use TypeScript for all new code' - 'Follow React best practices' - 'Implement proper error handling' testing: unit: - 'Jest for unit tests' - 'React Testing Library for components' e2e: - 'Cypress for end-to-end testing' documentation: required: - 'README.md in each major directory' - 'JSDoc comments for public APIs' - 'Changelog updates for all changes'
# Advanced .clinerules Example project: name: 'Enterprise Application' compliance: - 'GDPR requirements' - 'WCAG 2.1 AA accessibility' architecture: patterns: - 'Clean Architecture principles' - 'Domain-Driven Design concepts' security: requirements: - 'OAuth 2.0 authentication' - 'Rate limiting on all APIs' - 'Input validation with Zod'
# Deployment and DevOps Standards for Readability This document outlines the deployment and DevOps standards for Readability projects. Adhering to these standards will ensure maintainable, performant, and secure deployments. ## 1. Build Process and CI/CD ### 1.1. Standard: Utilize a modern CI/CD pipeline **Do This:** Implement a CI/CD pipeline using tools like Jenkins, GitHub Actions, GitLab CI, Azure DevOps, or CircleCI. **Don't Do This:** Manually build and deploy Readability applications. **Why:** Automation ensures consistency, reduces human error, and facilitates rapid iteration. **Explanation:** A well-defined CI/CD pipeline automates the process of building, testing, and deploying your Readability application. This includes tasks like code compilation, unit testing, integration testing, and deployment to staging and production environments. **Code Example (GitHub Actions):** """yaml name: Readability CI/CD on: push: branches: [ main ] pull_request: branches: [ main ] jobs: build: runs-on: ubuntu-latest steps: - uses: actions/checkout@v3 - name: Set up Python 3.11 uses: actions/setup-python@v4 with: python-version: '3.11' - name: Install dependencies run: | python -m pip install --upgrade pip pip install -r requirements.txt - name: Run tests with pytest run: pytest --cov=./readability --cov-report term-missing - name: Upload coverage to Codecov uses: codecov/codecov-action@v3 deploy: needs: build if: github.ref == 'refs/heads/main' runs-on: ubuntu-latest steps: - uses: actions/checkout@v3 - name: Configure AWS credentials uses: aws-actions/configure-aws-credentials@v2 with: aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }} aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }} aws-region: us-east-1 - name: Deploy to AWS Elastic Beanstalk run: | aws elasticbeanstalk update-environment \ --environment-name readability-prod \ --version-label ${{ github.sha }} """ **Anti-pattern:** Storing credentials directly in the CI/CD pipeline configuration. Use secrets management solutions provided by your CI/CD tool. ### 1.2. Standard: Implement automated testing **Do This:** Integrate unit tests, integration tests, and end-to-end tests into the CI/CD pipeline. **Don't Do This:** Rely solely on manual testing before deployment. **Why:** Automated testing ensures code quality, identifies regressions early, and reduces the risk of deploying faulty code. **Explanation:** Automated testing should cover various aspects of your Readability application, including individual components (unit tests), interactions between components (integration tests), and the entire application workflow (end-to-end tests). **Code Example (pytest):** """python # tests/test_readability.py import pytest from readability.readability import Readability def test_flesch_reading_ease(): text = "The cat sat on the mat." r = Readability(text) flesch = r.flesch_reading_ease() assert flesch.score > 90 # Example assertion, adjust as needed def test_flesch_kincaid_grade(): text = "The cat sat on the mat." r = Readability(text) grade = r.flesch_kincaid_grade() assert grade.score < 3 # Example assertion, adjust as needed # Add more tests for other Readability features """ **Anti-pattern:** Writing brittle tests that are tightly coupled to implementation details. Tests should focus on verifying the intended behavior of the application. Using excessive mocking instead of testing actual integration points. ### 1.3. Standard: Version control all deployment artifacts **Do This:** Use version control (e.g., Git) for all deployment artifacts, including configuration files, scripts, and infrastructure-as-code templates. **Don't Do This:** Manually manage and track changes to deployment artifacts. **Why:** Version control enables traceability, facilitates rollback, and promotes collaboration. **Explanation:** Storing deployment artifacts in a version control system allows you to track changes, revert to previous versions, and collaborate with other developers on deployment-related tasks. **Example (Git):** """bash git add deploy/config.ini git commit -m "Update configuration file for production environment" git push origin main """ **Anti-pattern:** Storing sensitive information (e.g., passwords, API keys) directly in version control. Use secrets management solutions to protect sensitive data. Ignoring or failing to track infrastructure-as-code changes, leading to inconsistencies between environments. ### 1.4. Standard: Utilize Infrastructure as Code (IaC) **Do This:** Define and manage your infrastructure using code (e.g., Terraform, CloudFormation, Ansible). **Don't Do This:** Manually provision and configure infrastructure. **Why:** IaC enables repeatable, consistent, and auditable infrastructure deployments. **Explanation:** Infrastructure as Code allows you to automate the provisioning and configuration of your infrastructure, ensuring consistency across environments and reducing the risk of human error. **Code Example (Terraform):** """terraform resource "aws_instance" "readability_app" { ami = "ami-0c55b9705ddc784bd" # Replace with your AMI instance_type = "t2.micro" tags = { Name = "readability-instance" } } resource "aws_security_group" "readability_sg" { name = "readability-sg" description = "Allow inbound traffic on port 8000" ingress { from_port = 8000 to_port = 8000 protocol = "tcp" cidr_blocks = ["0.0.0.0/0"] } egress { from_port = 0 to_port = 0 protocol = "-1" cidr_blocks = ["0.0.0.0/0"] } } """ **Anti-pattern:** Manually configuring infrastructure changes outside of IaC, leading to configuration drift. Failing to properly version control and manage Terraform state files. ## 2. Production Considerations ### 2.1. Standard: Implement comprehensive monitoring and alerting **Do This:** Use monitoring tools (e.g., Prometheus, Grafana, Datadog, New Relic) to track key performance indicators (KPIs) and set up alerts for critical events. **Don't Do This:** Deploy Readability applications without monitoring or alerting. **Why:** Monitoring and alerting enable proactive identification and resolution of issues, ensuring application availability and performance. **Explanation:** Implement monitoring to track metrics such as CPU utilization, memory usage, network traffic, and application response times. Configure alerts to notify you of critical events such as high error rates, slow response times, or system outages. **Example (Prometheus):** """yaml # prometheus.yml scrape_configs: - job_name: 'readability' metrics_path: '/metrics' static_configs: - targets: ['readability-app:8000'] # Replace with your Readability app address """ **Anti-pattern:** Ignoring monitoring data or failing to respond to alerts. Setting up too many alerts, leading to alert fatigue. Failing to customize monitoring to the unique needs of your Readability application. ### 2.2. Standard: Implement centralized logging **Do This:** Use a centralized logging system (e.g., ELK stack, Splunk, Graylog) to collect and analyze logs from all components of your Readability application. **Don't Do This:** Rely on local log files or manual log analysis. **Why:** Centralized logging enables efficient troubleshooting, security auditing, and compliance. **Explanation:** A centralized logging system collects logs from various sources, such as application servers, databases, and network devices, into a central repository. This allows you to easily search, analyze, and correlate log data to identify and resolve issues. **Example (ELK stack):** Configure your Readability application to send logs to Logstash, which then forwards them to Elasticsearch and Kibana. **Anti-pattern:** Storing logs without proper security measures, exposing sensitive information. Failing to properly index and structure log data, making it difficult to search and analyze. ### 2.3. Standard: Implement robust error handling and recovery mechanisms **Do This:** Implement error handling and recovery mechanisms at all levels of your Readability application, including client-side, server-side, and database layers. **Don't Do This:** Allow unhandled exceptions to crash the application or expose sensitive information to users. **Why:** Robust error handling ensures application stability, prevents data loss, and improves the user experience. **Explanation:** Implement error handling to catch exceptions, log errors, and provide informative error messages to users. Implement recovery mechanisms to automatically retry failed operations or gracefully degrade functionality in the event of an error. **Code Example (Python):** """python from readability.readability import Readability try: text = "" # or some other problematic input r = Readability(text) flesch = r.flesch_reading_ease() print(flesch.score) except ValueError as e: # Replace with specific exception type print(f"Error calculating readability: {e}") # Optionally, log the error for further investigation """ **Anti-pattern:** Displaying generic error messages to users, providing no useful information for troubleshooting. Suppressing errors without logging them, making it difficult to diagnose issues. Failing to implement proper rollback mechanisms for database transactions. ### 2.4. Standard: Implement security best practices **Do This:** Follow security best practices at all stages of the deployment process, including: * Using strong passwords and multi-factor authentication. * Regularly patching security vulnerabilities in your operating system and software dependencies. * Implementing appropriate access controls and permissions. * Encrypting sensitive data at rest and in transit. * Protecting against common web application vulnerabilities such as SQL injection, cross-site scripting (XSS), and cross-site request forgery (CSRF). **Don't Do This:** Neglect security considerations during deployment. **Why:** Security is paramount to protecting your application and data from unauthorized access and malicious attacks. **Explanation:** Use a password manager, enable multi-factor authentication where possible. Keep the operating system and the Readability library up to date by scheduling regular updates via your CI/CD pipeline. Apply the principle of least privilege. Encrypt sensitive data using industry-standard algorithms (e.g., AES, RSA). Sanitize user input to prevent SQL injection, implement output encoding to prevent XSS, and use CSRF tokens to protect against CSRF attacks. **Anti-pattern:** Hardcoding API keys or other secrets in configuration files. Exposing sensitive data in logs or error messages. Failing to regularly scan your application for security vulnerabilities. Ignoring security recommendations from your cloud provider or security tools. ### 2.5. Standard: Implement disaster recovery planning **Do This:** Develop and regularly test a disaster recovery plan to ensure business continuity in the event of a system outage or other disaster. **Don't Do This:** Assume that your application will always be available. **Why:** A disaster recovery plan minimizes downtime and data loss in the event of a disaster. **Explanation:** A disaster recovery plan should include procedures for backing up and restoring data, replicating the application to a secondary site, and failing over to the secondary site in the event of a disaster. **Example:** Regularly back up your database and store the backups in a separate location. Replicate your application to a different AWS region or availability zone. Implement automated failover procedures to switch traffic to the secondary site in the event of a primary site outage. Document these procedures and test them at least annually. **Anti-pattern:** Failing to test the disaster recovery plan regularly, leading to surprises during an actual disaster. Not having clear roles and responsibilities defined for disaster recovery. Relying on manual processes for disaster recovery, which can be slow and error-prone. ## 3. Readability Specific Considerations ### 3.1. Model Management Readability may depend on machine learning models. These models need: * Versioning -- which model version is in production? * Rollback -- if a new model degrades performance, how to revert? * Training pipelines -- how are new models trained and deployed? **Do This:** Use a model registry and pipeline tooling like MLflow, Kubeflow, or Sage Maker. Store models in a central location (e.g. cloud storage). **Don't Do This:** Deploy models manually or fail to track model lineage. ### 3.2. Readability as a Service If Readability operates as a REST API: * Rate limiting -- prevent abuse and ensure fair usage * API Versioning -- allow for breaking changes without disrupting clients * Input Sanitization -- protect against malicious input that could crash the system **Do This:** Implement API gateways like Kong or Tyk. Follow semantic versioning. Thoroughly test and validate all inputs. **Don't Do This:** Expose the core Readability logic directly without any access control. ### 3.3. Data Security Readability may handle sensitive text, depending on the application. * Anonymization -- remove or mask personal information * Data Retention -- only keep data for as long as necessary * Secure Storage -- protect text data at rest **Do This:** Use established anonymization techniques (e.g. NER masking). Enforce strict data retention policies. Use encryption and access controls in your data stores. **Don't Do This:** Store sensitive text without appropriate security measures. ### 3.4 Performance Tuning * Investigate slow operations based on profiling or monitoring data. * Optimize dependencies - consider alternatives or update to newer performant versions. * Cache data between calculations and calls. **Do This:** Profile the Readability operations upon example use case text, identify which operations create slowest performance impact. Add and maintain caching, using either in-memory caching or data store caching. Keep dependencies up to date with regular dependency scans. **Don't Do This:** Assume the Readability Library is completely optimized - tailor your implementation for your specific use case. By adhering to these deployment and DevOps standards, you can ensure that your Readability applications are deployed in a reliable, scalable, and secure manner. Remember to adapt these standards to the specific needs and requirements of your project.
# Code Style and Conventions Standards for Readability This document outlines the code style and conventions for developing Readability applications. Following these standards ensures consistency, readability, maintainability, and performance across the codebase. It is intended to be used by developers and as context for AI coding assistants. ## 1. General Formatting and Style ### 1.1. Indentation **Do This:** Use 4 spaces for indentation. Avoid tabs. **Don't Do This:** Use tabs or inconsistent indentation. **Why:** Consistent indentation improves readability and reduces errors. """python # Correct def my_function(arg1, arg2): if arg1 > arg2: return arg1 else: return arg2 # Incorrect def my_function(arg1, arg2): if arg1 > arg2: return arg1 else: return arg2 """ ### 1.2. Line Length **Do This:** Limit lines to 79 characters for code and 72 characters for docstrings and comments. **Don't Do This:** Exceed the line length limit, making code difficult to read and print. **Why:** Adhering to line length limits enhances readability, especially on smaller screens. """python # Correct - Using implicit line continuation def very_long_function_name( arg1, arg2, arg3, arg4, arg5, arg6): """ This is a long docstring describing the function and its parameters. """ return arg1 + arg2 + arg3 + arg4 + arg5 + arg6 # Incorrect def very_long_function_name(arg1, arg2, arg3, arg4, arg5, arg6): """This is a long docstring describing the function and its parameters.""" return arg1 + arg2 + arg3 + arg4 + arg5 + arg6 """ ### 1.3. Blank Lines **Do This:** * Use two blank lines between top-level function and class definitions. * Use one blank line between method definitions within a class. * Use blank lines sparingly inside functions to separate logical sections. **Don't Do This:** Inconsistent or excessive use of blank lines, which can clutter code. **Why:** Proper use of blank lines improves code organization. """python # Correct class MyClass: def method1(self): pass def method2(self): # logical separation x = 10 y = x + 5 return y def my_function(): pass # Incorrect class MyClass: def method1(self): pass def method2(self): x = 10 y = x + 5 return y def my_function(): pass """ ### 1.4. Whitespace **Do This:** * Use spaces around operators and after commas. * Use spaces around colons in dictionaries. * Do not use spaces inside parentheses, brackets, or braces. **Don't Do This:** Inconsistent or missing whitespace negatively impacts readability. **Why:** Standardized whitespace makes code cleaner and easier to parse visually. """python # Correct x = 1 + 1 my_list = [1, 2, 3] my_dict = {'key': 'value'} # Incorrect x=1+1 my_list=[1,2,3] my_dict={'key':'value'} """ ## 2. Naming Conventions ### 2.1. General Naming **Do This:** * Use descriptive and meaningful names. * Avoid single-character variable names (except for counters). * Be consistent. **Don't Do This:** Use obscure or misleading names that convey little information. **Why:** Clear names significantly improve the self-documenting nature of the code. ### 2.2. Variable Names **Do This:** use "snake_case" for variable names. **Don't Do This:** Use "camelCase" or other naming styles. **Why:** "snake_case" is the standard style for Python variables. """python # Correct user_name = "John Doe" item_count = 10 # Incorrect userName = "John Doe" ItemCount = 10 """ ### 2.3. Function Names **Do This:** Use "snake_case" for function names. **Don't Do This:** Use "camelCase" or inconsistent naming. **Why:** Consistency in function naming aids in recognizing code elements. """python # Correct def calculate_total(price, quantity): return price * quantity # Incorrect def CalculateTotal(price, quantity): return price * quantity """ ### 2.4. Class Names **Do This:** Use "CamelCase" for class names. **Don't Do This:** Use "snake_case" or inconsistent capitalization. **Why:** Following "CamelCase" for class names improves code clarity. """python # Correct class MyClass: pass # Incorrect class my_class: pass """ ### 2.5. Constant Names **Do This:** Use "UPPER_SNAKE_CASE" for constant names. **Don't Do This:** Use lowercase or mixed-case names for constants. **Why:** Distinguishing constants from variables is essential. """python # Correct MAX_SIZE = 100 DEFAULT_NAME = "Unknown" # Incorrect max_size = 100 defaultName = "Unknown" """ ## 3. Comments and Docstrings ### 3.1. Comments **Do This:** * Write comments to explain complex logic or non-obvious code. * Keep comments concise and up-to-date. * Use inline comments sparingly. * Begin comments with a capital letter and a space after the "#". **Don't Do This:** Over-comment obvious code or leave outdated comments. **Why:** Comments provide context and explain intent, improving code understanding. """python # Correct # This function calculates the area of a rectangle. def calculate_area(length, width): return length * width # Incorrect def calculate_area(length, width): # multiply length and width return length * width """ ### 3.2. Docstrings **Do This:** * Write docstrings for all modules, classes, functions, and methods. * Use triple quotes (""""Docstring goes here""""). * Include a brief description of the purpose, arguments, and return values. * Follow the reStructuredText or Google style for docstrings. * Where applicable, include examples using "doctest". **Don't Do This:** Omit docstrings, write vague docstrings, or neglect to update them. **Why:** Docstrings serve as the foundation for code documentation and help others understand the code's purpose and use. """python # Correct - Google style docstring def add(a, b): """Return the sum of two numbers. Args: a (int): The first number. b (int): The second number. Returns: int: The sum of a and b. Examples: >>> add(1, 2) 3 """ return a + b # Incorrect def add(a, b): """Adds two numbers.""" return a + b """ ## 4. Modern Python Features and Patterns (Readability Specific) ### 4.1. Type Hints **Do This:** Use type hints for function arguments and return values. **Don't Do This:** Omit type hints, especially in public APIs and complex code. **Why:** Type hints enhance code readability, aid in static analysis, and prevent type-related errors. """python # Correct def greet(name: str) -> str: return f"Hello, {name}" # Incorrect def greet(name): return f"Hello, {name}" """ ### 4.2. Data Classes **Do This:** Use "dataclasses" for simple data-holding classes. **Don't Do This:** Use traditional classes for simple data structures. **Why:** "dataclasses" reduce boilerplate code and improve readability. """python from dataclasses import dataclass # Correct @dataclass class Point: x: int y: int # Instead of: class Point: def __init__(self, x, y): self.x = x self.y = y """ ### 4.3. F-strings **Do This:** Use f-strings for string formatting. **Don't Do This:** Use "%" formatting or ".format()" unless required for legacy versions. **Why:** F-strings are more readable and efficient than older formatting methods. """python # Correct name = "Alice" age = 30 message = f"Hello, {name}. You are {age} years old." # Incorrect message = "Hello, %s. You are %d years old." % (name, age) message = "Hello, {}. You are {} years old.".format(name, age) """ ### 4.4. Context Managers **Do This:** Use "with" statements for resource management. **Don't Do This:** Explicitly open and close resources without using a context manager. **Why:** Context managers ensure resources are properly released, even in case of exceptions. """python # Correct with open('file.txt', 'r') as f: data = f.read() # Incorrect f = open('file.txt', 'r') data = f.read() f.close() """ ### 4.5. List Comprehensions and Generator Expressions **Do This:** Use list comprehensions and generator expressions for concise data manipulation. **Don't Do This:** Overuse them to the point of reduced readability; use regular loops for complex logic. **Why:** List comprehensions and generator expressions offer a compact way to create lists and iterators. """python # Correct squares = [x**2 for x in range(10)] even_numbers = (x for x in range(20) if x % 2 == 0) # Instead of: squares = [] for x in range(10): squares.append(x**2) """ ### 4.6. Enums **Do This:** Use "Enum" for defining a set of named symbolic values. **Don't Do This:** Use series of constant integers as enums. **Why:** Enums provides more readability and type safety. """python # Correct from enum import Enum class Color(Enum): RED = 1 GREEN = 2 BLUE = 3 # Incorrect RED = 1 GREEN = 2 BLUE = 3 """ ## 5. Readability-Specific Considerations ### 5.1 Asynchronous Programming (asyncio) **Do This:** * Use "async" and "await" keywords when dealing with asynchronous operations. * Structure code to avoid blocking the event loop. * Use "async with" for asynchronous context managers. **Don't Do This:** * Mix synchronous and asynchronous code without careful consideration. * Perform long-running CPU-bound operations on the main event loop. **Why:** Ensure that readability operations that could be long-running are handled efficiently and asynchronously to avoid blocking the main thread. """python import asyncio async def fetch_data(url: str) -> str: """Asynchronously fetches data from a URL.""" async with aiohttp.ClientSession() as session: # Requires aiohttp async with session.get(url) as response: return await response.text() async def main(): data = await fetch_data("https://example.com") print(data) if __name__ == "__main__": asyncio.run(main()) """ ### 5.2 Data Serialization **Do This:** Use standard library "json" module for simple serialization. Use dedicated serialization/deserialization libraries like "marshmallow" for complex object graphs with validation and schema. **Don't Do This:** Implement your own serialization logic except for trivial cases. **Why:** Using established, well-tested libraries provides security and performance benefits and ensures that code is easier to maintain. """python import json from dataclasses import dataclass @dataclass class Person: name: str age: int # Serialization person = Person("Alice", 30) person_json = json.dumps(person.__dict__) # Simple serialization for dataclasses print(person_json) # Deserialization person_dict = json.loads(person_json) person_deserialized = Person(**person_dict) print(person_deserialized) """ ### 5.3 Logging **Do This:** * Use the "logging" module to log important events, errors, and warnings. * Configure logging levels appropriately (DEBUG, INFO, WARNING, ERROR, CRITICAL). * Include sufficient context in log messages for debugging. **Don't Do This:** * Use "print" statements for logging (except for very simple scripts). * Log sensitive information. **Why:** Logging provides a structured way to track application behavior, diagnose issues, and monitor performance. """python import logging logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s') def process_data(data): logging.info(f"Processing data: {data}") try: result = data / 0 # Example of a potential error except ZeroDivisionError as e: logging.error(f"Error during processing: {e}", exc_info=True) # Captures the traceback return None return result data = 10 process_data(data) """ ### 5.4 Error Handling **Do This:** * Use "try...except" blocks to handle potential exceptions. * Be specific about the exceptions you catch. Avoid bare "except:" blocks. * Raise exceptions with descriptive error messages. * Use "finally" blocks for cleanup code that must always execute. **Don't Do This:** * Ignore exceptions or catch generic "Exception" without handling it. **Why:** Proper error handling prevents application crashes and provides meaningful feedback to users and developers. """python def divide(x, y): try: result = x / y except ZeroDivisionError: print("Cannot divide by zero.") return None except TypeError: # Be specific print("Invalid input types.") return None else: print("Division successful.") return result finally: print("Division attempt finished.") divide(10, 2) divide(5, 0) divide("a", "b") """ ### 5.5 Module Structure **Do This:** * Organize code into logical modules and packages. * Use relative imports within packages. * Define a clear API for each module. **Don't Do This:** Create monolithic files or scatter related code across multiple modules. **Why:** Modular code is easier to understand, test, and reuse. """ my_project/ ├── my_package/ │ ├── __init__.py │ ├── module1.py │ └── module2.py ├── main.py └── ... """ In "my_package/module1.py": """python from .module2 import some_function #Relative import """ In "main.py": """python from my_package import module1 """ ### 5.6 Dependency Management **Do This:** * Use "pip" and "venv" for managing dependencies. * Specify dependencies in a "requirements.txt" or "pyproject.toml" file. * Pin dependencies to specific versions to ensure reproducibility. **Don't Do This:** Rely on system-wide packages or ignore dependency management. **Why:** Consistent dependency management ensures that your application runs correctly in different environments. """bash # Create a virtual environment python3 -m venv .venv source .venv/bin/activate # Install dependencies pip install -r requirements.txt # Freeze dependencies pip freeze > requirements.txt """ ## 6. Security Considerations ### 6.1 Input Validation **Do This:** * Validate all user inputs to prevent injection attacks. * Use parameterized queries to prevent SQL injection. * Sanitize HTML inputs to prevent cross-site scripting (XSS). **Don't Do This:** Trust user inputs without validation. **Why:** Input validation is crucial for preventing security vulnerabilities. ### 6.2 Authentication and Authorization **Do This:** * Implement robust authentication and authorization mechanisms. * Use strong password hashing algorithms (e.g., bcrypt, Argon2). * Follow the principle of least privilege. **Don't Do This:** Store passwords in plain text or grant excessive permissions. ### 6.3 Data Protection **Do This:** * Encrypt sensitive data at rest and in transit. * Use HTTPS for all network communication. * Securely store API keys and secrets (e.g., using environment variables or a secrets manager). **Don't Do This:** Expose sensitive data in code or configuration files. ## 7. Performance Optimization ### 7.1 Algorithmic Efficiency **Do This:** * Choose appropriate data structures and algorithms for the task. * Optimize loops and avoid unnecessary iterations. * Profile code to identify performance bottlenecks. **Don't Do This:** Use inefficient algorithms or ignore performance issues. ### 7.2 Caching **Do This:** * Use caching to store frequently accessed data. * Invalidate or refresh cache entries when data changes. * Consider using memoization for expensive function calls. **Don't Do This:** Overuse caching without considering memory usage or data consistency. ### 7.3 Concurrency and Parallelism **Do This:** * Use threading or multiprocessing for CPU-bound tasks. * Use asynchronous programming for I/O-bound tasks. * Use libraries like "concurrent.futures" for easier concurrency management. **Don't Do This:** Introduce concurrency without careful consideration of thread safety and race conditions. ## 8. Conclusion Adhering to these code style and conventions standards will significantly enhance the quality, maintainability, and performance of Readability applications. This document serves as a guide for developers and a reference for AI coding assistants, promoting consistent and best practices across the codebase. Regularly review and update these standards to incorporate new features and best practices in the Readability ecosystem.
# Core Architecture Standards for Readability This document outlines the core architecture standards for Readability projects. It provides guidelines for structuring and organizing code to ensure maintainability, scalability, and performance. These standards are designed to work with automated coding assistants such as GitHub Copilot and Cursor. ## 1. Fundamental Architectural Pattern: Modular Monolith ### Standard * **Do This:** Embrace a modular monolith architecture. The Readability application should be structured as a single deployable unit, logically divided into independent modules. * **Don't Do This:** Avoid strict microservices from the start unless demonstrably required by scalability needs. Avoid a tightly coupled monolithic application. ### Explanation A modular monolith offers a balanced approach, providing the benefits of a single codebase (easier deployment, simplified testing) while maintaining logical separation of concerns (improved maintainability, independent development). This pattern allows for future migration to microservices if needed, without premature complexity. ### Code Example (Conceptual) """python # readability/ # ├── core/ # Shared kernel and utilities # ├── article_extraction/ # Module: Article extraction logic # ├── summarization/ # Module: Summarization algorithms # ├── user_management/ # Module: User account management # ├── api/ # API layer exposing functionalities # └── main.py # Entry point, configuration, setup """ ### Anti-Patterns * **Spaghetti Code:** Code that's highly interconnected and difficult to understand. * **God Class:** A single class that handles too many responsibilities. * **Premature Optimization:** Optimizing code before identifying actual performance bottlenecks. ## 2. Project Structure and Organization ### Standard * **Do This:** Organize the project into meaningful modules or packages based on domain or functionality. Enforce clear boundaries between modules through well-defined interfaces/APIs. * **Don't Do This:** Avoid circular dependencies between modules. Avoid scattering related functionality across the project. ### Explanation A well-organized project structure improves code navigation, reduces complexity, and makes it easier for developers to understand and contribute. Clear module boundaries prevent accidental coupling. ### Code Example (Python - Package Structure) """python # readability/ # ├── core/ # │ ├── __init__.py # │ ├── utils.py # General utility functions # │ ├── models.py # Base data models # ├── article_extraction/ # │ ├── __init__.py # │ ├── extractor.py # Core extraction logic # │ ├── parsers.py # HTML parsing implementations # │ ├── schemas.py # Data validation and serialization # │ └── ... # ├── summarization/ # │ ├── __init__.py # │ ├── summarizer.py # Main summarization class # │ ├── algorithms/ # Different summarization algorithms # │ │ ├── lsa.py # │ │ └── ... # │ └── ... # └── ... """ ### Anti-Patterns * **Flat Structure:** Placing all files in a single directory. * **Feature Envy:** A module excessively accesses data or methods of another module. ## 3. Dependency Injection and Inversion of Control ### Standard * **Do This:** Use dependency injection (DI) to manage dependencies between modules. Prefer constructor injection where possible. Utilize an Inversion of Control (IoC) container for complex dependency graphs, if appropriate (e.g. "Flask-DI" for Flask projects). * **Don't Do This:** Avoid hardcoding dependencies within modules. Avoid using global state to share dependencies. ### Explanation DI promotes loose coupling, making modules more testable and reusable. It allows for easy swapping of implementations without modifying the dependent modules. IoC containers manage complex object graphs efficiently. ### Code Example (Python - Constructor Injection) """python # article_extraction/extractor.py class ArticleExtractor: def __init__(self, html_parser): # Dependency injected via constructor self.html_parser = html_parser def extract_content(self, url): html = self.html_parser.fetch_html(url) # ... extract content from HTML using the injected parser return content # core/utils.py class RequestsHTMLParser: def fetch_html(self, url): import requests response = requests.get(url) return response.text # main.py (Example using Flask-DI) from flask import Flask from flask_di import Di from article_extraction.extractor import ArticleExtractor from core.utils import RequestsHTMLParser app = Flask(__name__) di = Di(app) def configure(binder): binder.bind(ArticleExtractor, to=ArticleExtractor(RequestsHTMLParser())) # Binding with app.app_context(): extractor: ArticleExtractor = di.get(ArticleExtractor) #Resolving Dependency """ ### Anti-Patterns * **Service Locator:** Modules explicitly ask a service locator for dependencies, which reduces testability. * **Singleton Abuse:** Using singletons to provide dependencies, which makes it difficult to mock dependencies in tests. ## 4. API Design and Communication ### Standard * **Do This:** Design clear, well-defined APIs for module communication. Use appropriate data serialization formats (e.g., JSON, Protocol Buffers) and API styles (e.g., REST, GraphQL). * **Don't Do This:** Expose internal data structures through APIs. Avoid overly chatty APIs. ### Explanation Well-designed APIs ensure loose coupling between modules and allow for independent evolution. Using appropriate data formats and API styles improves interoperability and performance. ### Code Example (Python - REST API with Flask) """python # api/routes.py from flask import Flask, request, jsonify from article_extraction.extractor import ArticleExtractor from core.utils import RequestsHTMLParser app = Flask(__name__) extractor = ArticleExtractor(RequestsHTMLParser()) @app.route('/extract', methods=['POST']) def extract_article(): url = request.json.get('url') if not url: return jsonify({'error': 'URL is required'}), 400 try: content = extractor.extract_content(url) return jsonify({'content': content}), 200 except Exception as e: return jsonify({'error': str(e)}), 500 if __name__ == '__main__': app.run(debug=True) """ ### Anti-Patterns * **Leaky Abstraction:** The API exposes implementation details. * **Remote Procedure Call (RPC) Abuse:** Using RPC-style APIs for everything, leading to tight coupling. ## 5. Data Management and Persistence ### Standard * **Do This:** Abstract data access logic using a Repository pattern. Use an ORM (e.g., SQLAlchemy) or ODM (e.g., MongoEngine) for database interaction. Define clear data models and schemas. * **Don't Do This:** Directly embed SQL queries within application logic. Expose database implementation details to other modules. ### Explanation The Repository pattern separates data access logic from the business logic, making the application more maintainable and testable. ORMs and ODMs simplify database interactions and provide object-oriented data access. Clear data models ensure data consistency and integrity. ### Code Example (Python - Repository Pattern with SQLAlchemy) """python # core/models.py from sqlalchemy import Column, Integer, String from sqlalchemy.ext.declarative import declarative_base from sqlalchemy.orm import sessionmaker Base = declarative_base() class Article(Base): __tablename__ = 'articles' id = Column(Integer, primary_key=True) url = Column(String) content = Column(String) def __repr__(self): return f"<Article(url='{self.url}', content='{self.content[:50]}...')>" # data/article_repository.py using repository pattern from sqlalchemy import create_engine from sqlalchemy.orm import sessionmaker from core.models import Article, Base class ArticleRepository: def __init__(self, db_url='sqlite:///:memory:'): self.engine = create_engine(db_url) Base.metadata.create_all(self.engine) self.Session = sessionmaker(bind=self.engine) def get_article(self, url): with self.Session() as session: return session.query(Article).filter_by(url=url).first() def add_article(self, url, content): with self.Session() as session: article = Article(url=url, content=content) session.add(article) session.commit() def delete_article(self, url): with self.Session() as session: article = session.query(Article).filter_by(url=url).first() if article: session.delete(article) session.commit() """ ### Anti-Patterns * **Active Record:** Data models directly handle persistence logic, leading to tight coupling. * **Database as API:** Exposing the database directly to client applications. ## 6. Error Handling and Logging ### Standard * **Do This:** Implement comprehensive error handling using exceptions. Log errors and warnings using a logging framework (e.g., "logging" in Python). Use structured logging (e.g. JSON formatted logs). Implement centralized exception handling. * **Don't Do This:** Ignore exceptions. Print error messages to the console without logging. Expose sensitive information in error messages. ### Explanation Robust error handling and logging are crucial for debugging, monitoring, and maintaining the application. Structured logging facilitates analysis and troubleshooting. ### Code Example (Python - Error Handling and Logging) """python import logging import json # Configure logging logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s') def extract_article_info(url): """ Extracts information from a given URL and logs any errors encountered. """ try: # Simulate fetching the HTML content (replace with actual extraction logic) # For example: html_content = fetch_html(url) logging.info(json.dumps({'event': 'article_extraction_started', 'url': url})) # Simulate an error condition raise ValueError("Simulated error during article extraction") article_content = "Dummy article content" logging.info(json.dumps({'event':'article_extraction_success', 'url': url})) # Log extraction success return article_content except ValueError as ve: logging.error(json.dumps({'event': 'article_extraction_failed', 'url': url, 'error': str(ve)}), exc_info=True) return None # Or raise the exception depending on the use case except Exception as e: # Catch-all for any other unexpected errors logging.exception(json.dumps({'event': 'unexpected_error_during_extraction', 'url': url, 'error': str(e)})) #Using logging.exception to capture traceback return None """ ### Anti-Patterns * **Catch-All Exception Handling:** Catching all exceptions without handling them properly. * **Silent Failure:** The application continues to run without reporting an error. ## 7. Concurrency and Parallelism ### Standard * **Do This:** Use appropriate concurrency models (e.g., threads, asyncio) for I/O-bound and CPU-bound tasks. Use thread pools or process pools to manage concurrency. Handle race conditions and deadlocks carefully. * **Don't Do This:** Use global state in concurrent code without proper synchronization. Create too many threads or processes, leading to resource exhaustion. ### Explanation Concurrency and parallelism can significantly improve application performance, but they also introduce complexities. Choosing the right concurrency model and handling synchronization issues are crucial. ### Code Example (Python - Asyncio for Concurrent Web Requests) """python import asyncio import aiohttp async def fetch_url(session, url): try: async with session.get(url
# API Integration Standards for Readability This document outlines the coding standards for integrating Readability with backend services and external APIs. Adhering to these standards will ensure maintainable, performant, and secure code. ## 1. Architectural Patterns for API Integration ### 1.1 Separation of Concerns (SoC) **Standard:** Isolate API integration logic from the core Readability components. **Do This:** * Create dedicated modules or services responsible for API communication. * Use interfaces or abstract classes to define the interaction contracts between Readability and the API integration layer. **Don't Do This:** * Embed API calls directly within UI components or core business logic. * Mix API logic with data transformation or presentation logic. **Why:** SoC enhances maintainability, testability, and reusability. Changes to the API or Readability core will have minimal impact on other parts of the application. **Example:** """python # api_service.py import requests import json from typing import Dict, Any class ApiService: def __init__(self, base_url: str): self.base_url = base_url def get_data(self, endpoint: str, params: Dict[str, Any] = None) -> Dict[str, Any]: """ Fetches data from the API endpoint. """ url = f"{self.base_url}/{endpoint}" try: response = requests.get(url, params=params) response
# Performance Optimization Standards for Readability This document outlines coding standards specifically for performance optimization in Readability projects. Adhering to these standards will ensure application speed, responsiveness, and efficient resource usage, leading to a better user experience. ## 1. Architectural Considerations for Performance ### 1.1. Data Structures and Algorithms **Standard:** Choose appropriate data structures and algorithms based on performance characteristics (time and space complexity) and the specific requirements of the Readability components. * **Do This:** Analyze algorithmic complexity before implementation. Use profilers to identify performance bottlenecks. Select data structures that align with access patterns (e.g., use a hash map for fast lookups). * **Don't Do This:** Blindly use simple data structures like arrays/lists for complex operations without considering their performance implications. Neglect assessing the efficiency of complex algorithms. **Why:** Efficiency in data handling directly translates to faster processing within Readability, minimizing latency and maximizing throughput. Slow operations can impact the perception of readability and negatively impact engagement. **Code Example (Python):** """python # Inefficient (O(n) lookup) my_list = ["apple", "banana", "cherry"] if "banana" in my_list: print("Banana found") # Efficient (O(1) lookup) my_set = {"apple", "banana", "cherry"} if "banana" in my_set: print("Banana found") """ **Anti-Pattern:** Using linear search when a binary search (requires a sorted data structure) or a hash table lookup would be more efficient. ### 1.2. Caching Strategies **Standard:** Implement caching at different levels (e.g., browser, server, database) to reduce redundant computations and data retrieval. * **Do This:** Use browser caching for static assets (CSS, JavaScript, images). Implement server-side caching for frequently accessed data or computed results. Consider using a content delivery network (CDN) for content distribution. Utilize database caching mechanisms (e.g., query caching). * **Don't Do This:** Cache indiscriminately. Improper cache invalidation can lead to stale data. Omit cache expiration policies, allowing caches to grow indefinitely. **Why:** Caching minimizes latency and server load, enhancing responsiveness and scalability of Readability. **Code Example (Server-side caching with Redis using Python and Flask):** """python from flask import Flask, jsonify import redis import time app = Flask(__name__) redis_client = redis.Redis(host='localhost', port=6379, db=0) def get_expensive_data(key): """Simulates an expensive operation (e.g., database query).""" time.sleep(2) # Simulate delay return f"Data for {key} - generated at {time.time()}" @app.route('/data/<key>') def data_endpoint(key): cached_data = redis_client.get(key) if cached_data: print("Data retrieved from cache") return jsonify({"data": cached_data.decode('utf-8')}) #Important to decode from bytes data = get_expensive_data(key) redis_client.setex(key, 60, data) # Cache for 60 seconds print("Data retrieved from source and cached") return jsonify({"data": data}) if __name__ == '__main__': app.run(debug=True) """ **Anti-Pattern:** Neglecting cache invalidation, leading to users seeing outdated information. Setting excessive cache times without a proper invalidation strategy. ### 1.3. Asynchronous Processing and Concurrency **Standard:** Use asynchronous processing and concurrency to handle long-running tasks effectively, preventing blocking operations on the main thread/process. * **Do This:** Leverage asynchronous frameworks like "asyncio" (Python) for I/O-bound operations. Utilize thread pools or process pools for CPU-bound operations. Employ message queues (e.g., RabbitMQ, Kafka) for decoupling tasks. * **Don't Do This:** Block the main thread/process with synchronous operations. Overuse threads/processes, leading to context-switching overhead and resource contention. Ignore potential race conditions and deadlocks when using concurrency. **Why:** Asynchronous processing improves responsiveness, especially in scenarios involving network requests, file processing, or computationally intensive analysis within Readability. **Code Example (Asynchronous processing with "asyncio" in Python):** """python import asyncio import time async def fetch_data(item): """Simulates fetching data (e.g., from a URL).""" print(f"Fetching data for {item}...") await asyncio.sleep(1) # Simulate network latency print(f"Data fetched for {item}") return f"Data: {item} at {time.time()}" async def process_items(items): """Processes a list of items concurrently.""" tasks = [fetch_data(item) for item in items] results = await asyncio.gather(*tasks) # Run tasks concurrently return results async def main(): items = ["Item1", "Item2", "Item3"] results = await process_items(items) for result in results: print(result) if __name__ == "__main__": asyncio.run(main()) """ **Anti-Pattern:** Performing computationally expensive tasks within the main event loop, causing UI freezes. Improperly managing concurrency leading to data corruption. ### 1.4 API Design **Standard**: Design APIs for efficiency, focusing on minimizing data transfer and optimizing server-side processing. Consider GraphQL over REST for greater flexibility in requesting specific data, reducing over-fetching. * **Do This**: Implement pagination for large datasets. Support filtering and sorting at the API level. Use data compression techniques. Rate limit API requests. * **Don't Do This**: Return excessive or unnecessary data in API responses. Make the client perform filtering/sorting when the server can handle it more efficiently. Neglect security considerations when designing APIs. **Why**: Efficient APIs reduce network bandwidth usage and improve server-side processing time directly impacting the perceived speed and efficiency of the Readability platform. **Code Example (Node.js with Express and pagination):** """javascript const express = require('express'); const app = express(); const items = Array.from({length: 100}, (_, i) => "Item ${i+1}"); // create 100 items app.get('/items', (req, res) => { const page = parseInt(req.query.page) || 1; // default to page 1 const limit = parseInt(req.query.limit) || 10; // default to 10 items per page const startIndex = (page - 1) * limit; const endIndex = page * limit; const results = {}; if (endIndex < items.length) { results.next = { page: page + 1, limit: limit }; } if (startIndex > 0) { results.previous = { page: page - 1, limit: limit }; } results.results = items.slice(startIndex, endIndex); res.json(results); }); app.listen(3000, () => console.log('Server started on port 3000')); """ **Anti-Pattern**: Returning full datasets when only a subset is needed. Making redundant API calls. Omitting error handling. ## 2. Code-Level Optimization ### 2.1. Memory Management **Standard:** Optimize memory usage to prevent memory leaks and excessive memory consumption. * **Do This:** Profile memory usage to identify memory leaks. Use garbage collection mechanisms efficiently. Free unused resources promptly. Avoid creating unnecessary objects. Employ data structures that minimize memory footprint. * **Don't Do This:** Create large, persistent objects without proper management. Forget to release resources (e.g., file handles, database connections). Accidentally hold references to objects, preventing garbage collection. **Why:** Efficient memory management prevents application crashes, reduces GC overhead, and improves overall performance. Especially on systems with limited resources (mobile or embedded systems). **Code Example (Python):** """python import gc def process_data(data): """Processes a large dataset.""" temp_list = [item * 2 for item in data] # List comprehension # ... perform operations on temp_list ... del temp_list # Explicitly delete to release memory gc.collect() # Force garbage collection (optional, but can be useful) data = list(range(1000000)) process_data(data) """ **Anti-Pattern:** Accumulating large amounts of data in memory without releasing it, leading to OutOfMemoryError. Creating unnecessary object copies. ### 2.2. String Handling **Standard:** Handle strings efficiently, minimizing string concatenation and object creation. * **Do This:** Use string builders or efficient string concatenation methods instead of repeatedly concatenating strings with the "+" operator (especially in loops). Avoid unnecessary string conversions. Utilize string interning where appropriate. * **Don't Do This:** Use inefficient string concatenation techniques. Create excessive temporary string objects. Perform redundant string operations. **Why:** String operations can be performance-intensive. Efficient string handling reduces memory allocation and improves processing speed. **Code Example (Java):** """java // Inefficient String result = ""; for (int i = 0; i < 1000; i++) { result += "Iteration " + i; } // Efficient StringBuilder sb = new StringBuilder(); for (int i = 0; i < 1000; i++) { sb.append("Iteration ").append(i); } String result = sb.toString(); """ **Anti-Pattern:** Using repeated string concatenation with the "+" operator within loops, leading to O(n^2) complexity. Unnecessary string conversions. ### 2.3. Loop Optimization **Standard:** Optimize loops and iterations for performance, minimizing unnecessary computations and improving cache locality. * **Do This:** Minimize computations within loops. Use loop unrolling or vectorization techniques (if supported by the language/platform). Optimize inner loops first. Ensure proper indexing and avoid out-of-bounds access. * **Don't Do This:** Perform redundant computations within loops. Ignore loop invariants. Access memory in a non-sequential manner. **Why:** Loops are often critical performance bottlenecks. Optimizing loops can significantly improve application speed. **Code Example (Python with NumPy):** """python import numpy as np # Inefficient (Python loop) a = [i for i in range(1000000)] b = [i*2 for i in range(1000000)] result = [] for i in range(len(a)): result.append(a[i] + b[i]) # Efficient (NumPy vectorization) a = np.arange(1000000) b = np.arange(1000000) * 2 result = a + b """ **Anti-Pattern:** Performing the same calculation repeatedly within a loop. Using inefficient loop constructs. ### 2.4. Regular Expressions **Standard**: Use regular expressions carefully, understanding their performance implications. Compile regular expressions for reuse. Avoid overly complex regex patterns. * **Do This**: Compile regular expressions for repeated use (especially within loops). Use specific patterns instead of overly generic ones. Test regex performance with representative data. * **Don't Do This**: Use overly complex regular expressions that can lead to catastrophic backtracking. Create regular expressions dynamically within loops. **Why:** Inefficient regular expressions can be extremely slow and CPU-intensive. **Code Example (Python):** """python import re # Inefficient: Recompiling the regex on each call. def find_matches_inefficient(text, pattern): return re.findall(pattern, text) # Efficient: Compiling the regex once and reusing it. compiled_pattern = re.compile(r'\d+') # Example pattern: matches one or more digits def find_matches_efficient(text, compiled_pattern): return compiled_pattern.findall(text) text = "This is a string with some numbers like 123 and 456." matches1 = find_matches_efficient(text, compiled_pattern) print(matches1) #Output: ['123', '456'] matches2 = find_matches_efficient("Another string 789", compiled_pattern) print(matches2) # Output: ['789'] """ **Anti-Pattern**: Using very complex regular expressions to parse highly structured data: consider a dedicated parser instead. Forgetting to escape special characters properly leading to unexpected behavior. ## 3. Framework and Technology-Specific Optimizations ### 3.1. Readability Specific Module Optimization **Standard**: When working with Readability modules (or any third party plugins or frameworks), understand how to efficiently use their facilities. Use profiling tools to see which modules are creating bottlenecks. * **Do This**: Use modules sparingly, only importing what is needed. Investigate specific module's best practices for optimal performance (example: If using a database connector, use connection pooling). Lazy Load Modules when appropriate. * **Don't Do This**: Import entire modules when only a small part is needed. Neglect to read the documentation on module performance and resource usage. **Why**: Minimizing the dependency footprint and leveraging best practices specific to your chosen modules improves overall application performance. **Code Example (Python):** *(This is a general example, replace with specific Readability module usage)* """python # Instead of: # import readability_module # readability_module.HeavyFunction1() # readability_module.HeavyFunction2() # Do: # from readability_module import HeavyFunction1, HeavyFunction2 # HeavyFunction1() # HeavyFunction2() """ **Anti-Pattern**: Blindly importing entire packages, leading to unnecessary overhead. Ignoring the specific performance recommendations of selected modules. ### 3.2: Front-End Optimization (If Applicable) While the core of Readability might focus on server-side logic; if there's a front-end component it is important to consider these aspects: * **Minification and Bundling**: Minify CSS and JavaScript files to reduce file sizes. Bundle multiple files into fewer requests. * **Image Optimization**: Optimize images for the web using appropriate formats (WebP, JPEG, PNG) and compression techniques. Use responsive images. * **Lazy Loading**: Lazy load images and other assets that are not immediately visible. * **Browser Caching**: Leverage browser caching appropriately. **Why**: Optimizing the front-end improves page load times and responsiveness, leading to better user engagement. ## 4. Profiling and Monitoring ### 4.1. Performance Profiling **Standard:** Use profiling tools to identify performance bottlenecks and areas for optimization. * **Do This:** Use CPU profilers, memory profilers, and I/O profilers. Profile code in representative environments. Analyze profiling data to identify hotspots. Use profiling to measure the impact of optimizations. * **Don't Do This:** Optimize code without profiling. Rely on intuition alone. Ignore performance metrics. **Why:** Profiling provides data-driven insights into performance bottlenecks, guiding optimization efforts effectively. **Code Example (Using "cProfile" in Python):** """python import cProfile import pstats def my_function(): """A function to profile.""" # ... code to profile ... pass cProfile.run('my_function()', 'profile_output') p = pstats.Stats('profile_output') p.sort_stats('cumulative').print_stats(20) # Display top 20 functions by cumulative time """ **Anti-Pattern:** Guessing at performance bottlenecks without empirical evidence. Neglecting to use available profiling tools. ### 4.2. Performance Monitoring **Standard:** Implement monitoring to track application performance in production environments. * **Do This:** Track key performance indicators (KPIs) such as response time, throughput, error rate, and resource usage. Set up alerts for performance degradation. Use monitoring tools to analyze performance trends. Integrate monitoring into your deployment pipeline. * **Don't Do This:** Deploy code without monitoring. Ignore performance alerts. Fail to analyze performance trends. **Why:** Monitoring provides visibility into application performance, enabling early detection of issues and proactive optimization. This comprehensive Performance Optimization Standards document helps ensure the Readability project consistently achieves high levels of performance, speed, and efficiency. The examples provided serve as starting points; always adapt these to the specific contexts of your Readability development.