Azure Bootstrap Library

Production-ready Azure bootstrap library for seamless integration of Azure App Configuration, Key Vault, and Application Insights into Azure Functions applications.

📦 What is This Repository?

This repository contains the source code and build configuration for the azure-bootstrap pip library - a reusable bootstrap package used across 17+ Azure Functions repositories in the organization.

Package Name: azure-bootstrap Current Version: 1.0.0 Distribution: PyPI (public)

🎯 Purpose

This library solves the circular dependency problem between logging and configuration in Azure Functions:

• Configuration loading needs logging → But logging needs configuration → 🐔🥚
• Our solution: 4-phase bootstrap that provides working logging throughout the entire process

What This Library Does

1. Bootstrap Logging - Logging that works immediately, before configuration loaded
2. Configuration Loading - Azure App Configuration with automatic Key Vault secret resolution
3. Telemetry Setup - Application Insights with OpenTelemetry
4. Environment Loading - All configs automatically loaded to os.environ with smart local overrides

📋 Table of Contents

• Quick Start
• Installation
• Configuration
• Usage Examples
• API Reference
• Migration Guide
• Development
• Contributing
• Troubleshooting

🚀 Quick Start

For Library Users

"""function_app.py"""
import os
import azure.functions as func
from azure_bootstrap import initialize_application, get_bootstrap_logger

_bootstrap_initialized = False
_logger = None

def _ensure_bootstrap():
    global _bootstrap_initialized, _logger
    if _bootstrap_initialized:
        return

    _logger = get_bootstrap_logger(__name__)
    config_repo = initialize_application()
    _bootstrap_initialized = True

app = func.FunctionApp()

@app.route(route="hello")
def hello(req):
    _ensure_bootstrap()
    db_host = os.getenv("DATABASE_HOST")  # All configs in os.environ
    return func.HttpResponse(f"Hello! DB: {db_host}")

For Library Developers

git clone https://github.com/TheViziusGroup/azure-bootstrap
cd azure-bootstrap
python -m venv .venv
.venv\Scripts\activate
pip install -e ".[dev]"
pytest

📦 Installation

From PyPI

pip install azure-bootstrap

Add to requirements.txt:

azure-bootstrap>=1.0.0

⚙️ Configuration

Option 1: Enterprise (Azure App Configuration + Key Vault)

local.settings.json:

{
  "Values": {
    "AZURE_APP_CONFIGURATION_CONNECTION_STRING": "Endpoint=https://...;Id=...;Secret=...",
    "AZURE_KEY_VAULT_URL": "https://myvault.vault.azure.net/",
    "AZURE_APP_CONFIG_LABEL": "dev"
  }
}

Option 2: Simple (Environment Variables Only)

local.settings.json:

{
  "Values": {
    "DATABASE_HOST": "localhost",
    "DATABASE_NAME": "mydb",
    "API_KEY": "your-api-key"
  }
}

The library gracefully falls back to environment variables when App Configuration is not available.

Configuration Precedence

Priority Order (highest to lowest):

1. Environment variables (os.environ) - Local overrides win
2. Azure App Configuration - Centralized config
3. Key Vault secrets - Secure secrets (via App Config references)
4. Default values - Fallback

Example:

# local.settings.json sets: USE_MOCK_DB = "true"
# App Config has: USE_MOCK_DB = "false"
# After bootstrap: os.getenv("USE_MOCK_DB") → "true" (local wins!)

💡 Usage Examples

Complete Azure Functions Example

See examples/function_app_example.py for a production-ready example.

Basic Usage

from azure_bootstrap import initialize_application, get_bootstrap_logger

logger = get_bootstrap_logger(__name__)
config_repo = initialize_application()

# All configs now in os.environ
db_host = os.getenv("DATABASE_HOST")

Custom Secrets Repository

from azure_bootstrap import initialize_application, SecretsRepository

secrets_repo = SecretsRepository(vault_url="https://custom-vault.vault.azure.net/")
config_repo = initialize_application(secrets_repository=secrets_repo)

Without Auto-Loading to os.environ

from azure_bootstrap import create_enhanced_config_repository

config_repo = create_enhanced_config_repository(
    app_config_connection_string=conn_str,
    auto_load_to_environ=False
)

# Manually access values
db_host = config_repo.get_value("DATABASE_HOST")

📖 API Reference

Main Functions

initialize_application(secrets_repository=None)

Main bootstrap function that initializes the entire application.

Returns: EnhancedConfigRepository instance

Example:

config_repo = initialize_application()

get_bootstrap_logger(name)

Get a logger that works during bootstrap phase.

Parameters: name (str) - Logger name (typically __name__)

Returns: logging.Logger

Example:

logger = get_bootstrap_logger(__name__)

create_enhanced_config_repository(...)

Create a configuration repository with App Config and Key Vault support.

Parameters:

• app_config_connection_string (str): Azure App Configuration connection string
• secrets_repository (optional): Custom secrets repository
• auto_load_to_environ (bool): Auto-load configs to os.environ

Returns: EnhancedConfigRepository

Core Classes

• ApplicationBootstrap - Bootstrap orchestrator
• EnhancedConfigRepository - Configuration repository
• SecretsRepository - Key Vault secrets repository
• TelemetryManager - Telemetry and App Insights manager
• BootstrapLogger - Bootstrap logging manager

Interfaces

All components implement interfaces for testability:

• ApplicationBootstrapInterface
• EnhancedConfigRepositoryInterface
• SecretsRepositoryInterface
• TelemetryManagerInterface
• BootstrapLoggerInterface

🔄 Migration Guide

Converting Projects from Local Bootstrap Code

Step 1: Backup and Branch

git checkout -b backup-before-bootstrap-migration
git push origin backup-before-bootstrap-migration
git checkout -b migrate-to-bootstrap-library

Step 2: Install and Update Imports

pip install azure-bootstrap

# BEFORE:
from src.infrastructure.application_bootstrap import initialize_application
from src.infrastructure.bootstrap_logging import get_bootstrap_logger

# AFTER:
from azure_bootstrap import initialize_application, get_bootstrap_logger

Find all files to update:

grep -r "from src.infrastructure" .
grep -r "from src.repositories.enhanced_config_repository" .
grep -r "from src.repositories.secrets_repository" .

Step 3: Remove Local Bootstrap Files

rm -rf src/infrastructure/
# Only remove these if you don't have app-specific extensions:
rm -f src/repositories/enhanced_config_repository.py
rm -f src/repositories/secrets_repository.py

Step 4: Update requirements.txt

azure-bootstrap>=1.0.0
# Remove: azure-appconfiguration-provider, azure-keyvault-secrets,
# azure-identity, azure-monitor-opentelemetry (now included in library)

Step 5: Update Deployment Pipeline

# In your CI/CD pipeline, just install from PyPI:
- script: pip install -r requirements.txt

Migration Scenarios

Post-Migration Checklist

• Application starts without errors
• Bootstrap logging works
• App Configuration loads (if configured)
• Key Vault secrets resolve (if configured)
• App Insights telemetry works
• All functions work as expected

Rollback Plan

# Revert migration
git revert <commit-hash>

# Or switch to backup branch
git checkout backup-before-bootstrap-migration

🛠️ Development

Setup Development Environment

# Clone repository
git clone https://github.com/TheViziusGroup/azure-bootstrap
cd azure-bootstrap

# Create virtual environment
python -m venv .venv
.venv\Scripts\activate  # Windows
source .venv/bin/activate  # Linux/Mac

# Install with dev dependencies
pip install -e ".[dev]"

# Verify setup
pytest

Run Tests

# All tests with coverage
pytest --cov=azure_bootstrap --cov-report=term-missing

# Specific test
pytest test/services/test_application_bootstrap.py -v

# Generate HTML coverage report
pytest --cov=azure_bootstrap --cov-report=html
open htmlcov/index.html

Build Package

# Install build tools
pip install build twine

# Build wheel and source distribution
python -m build

# Output:
# dist/azure_bootstrap-1.0.0-py3-none-any.whl
# dist/azure_bootstrap-1.0.0.tar.gz

# Verify package
twine check dist/*

Publish to PyPI

# Manual publish
pip install twine
twine upload dist/*

# Or automated via pipeline
git tag v1.0.0
git push origin main --tags

👥 Contributing

We welcome contributions! Please follow these guidelines:

Git Workflow (Gitflow)

main (production)
└── dev (integration)
    ├── feature/feature-name
    ├── bugfix/bug-description
    └── hotfix/critical-fix

Branch Types

• feature/* - New features (branch from dev, merge to dev)
• bugfix/* - Bug fixes (branch from dev, merge to dev)
• hotfix/* - Critical fixes (branch from main, merge to main AND dev)
• release/* - Release preparation (branch from dev, merge to main and dev)

Quality Standards

• ✅ Test Coverage: Minimum 80% (90% for new code)
• ✅ Code Style: Black formatting, Ruff linting
• ✅ Type Hints: Required for all public APIs
• ✅ Documentation: Docstrings for all public functions
• ✅ Commit Messages: Conventional Commits format

Pre-PR Checklist

# Format code
black azure_bootstrap/ test/

# Lint code
ruff check azure_bootstrap/ test/

# Type check
mypy azure_bootstrap/

# Run tests
pytest --cov=azure_bootstrap --cov-report=term-missing

# All checks must pass ✅

See CONTRIBUTING.md for complete guidelines.

🔧 Troubleshooting

Common Issues

Issue: Module not found

# Solution
pip install azure-bootstrap

Issue: Import errors

# WRONG
from azure_bootstrap.infrastructure import initialize_application

# CORRECT
from azure_bootstrap import initialize_application

Issue: Tests failing

# Clean environment
rm -rf .venv
python -m venv .venv
.venv\Scripts\activate
pip install -e ".[test]"
pytest

Issue: Package not found on PyPI

# Verify the package is published
pip install azure-bootstrap --verbose

📚 Documentation

Core Documentation

Examples

📋 Repository Structure

azure-bootstrap/
├── azure_bootstrap/          # 📦 Main package (17 .py files)
│   ├── models/                   # Exception definitions
│   ├── repositories/             # Config & secrets repositories
│   └── services/                 # Bootstrap services
├── test/                         # 🧪 Test suite (80%+ coverage)
├── examples/                     # 💡 Usage examples
├── .github/workflows/ci-cd.yml   # 🔄 GitHub Actions CI/CD
├── .githooks/                    # 🪝 Git hooks (pre-commit, pre-push)
├── .vscode/                      # 💻 VS Code workspace config
├── pyproject.toml                # ⚙️ Package configuration
├── README.md                     # 👈 You are here
├── CLAUDE.md                     # 🤖 AI assistant context & version history
├── CONTRIBUTING.md               # 👥 Contribution guidelines & tooling setup
└── LICENSE                       # 📄 License file

🧪 Testing

Test Coverage

• Current: 82% overall coverage (82.43%)
• Requirement: 80% minimum, 90% for new code
• Critical Paths: 100% coverage (bootstrap flow, config loading)

Run Tests

pytest                           # All tests
pytest -v                        # Verbose
pytest --cov                     # With coverage
pytest test/services/ -v         # Specific directory

📦 Package Distribution

What Gets Distributed

✅ Package code (17 .py files) ✅ Type hints (py.typed) ✅ LICENSE file

What Doesn't Get Distributed

❌ Tests (test/) ❌ Examples (examples/) ❌ Development files (.gitignore, etc.) ❌ Build artifacts (dist/, build/)

See MANIFEST.in for distribution control.

🔄 CI/CD Pipeline

GitHub Actions Workflow

The library uses GitHub Actions for continuous integration and deployment. The workflow automatically:

1. Build & Test - Installs dependencies, runs tests with coverage
2. Publish - Uploads package to PyPI (main branch and tags only)
3. Validate - Tests installation from feed

Triggers

• Push to main → Stable release (e.g., 1.0.0)
• Push to develop → Development release with timestamp (e.g., 1.0.0.dev20250124123456)
• Pull requests → Build and test only (no publish)
• Tags (v)* → Tagged stable release

See .github/workflows/ci-cd.yml for workflow configuration.

For complete CI/CD setup instructions, see the CI/CD Setup section in CLAUDE.md.

📝 Version Management

Semantic Versioning

• Major (X.0.0) - Breaking API changes
• Minor (0.X.0) - New features (backwards compatible)
• Patch (0.0.X) - Bug fixes

Current Version: 1.0.0

See the Version History section in CLAUDE.md for detailed changelog.

🎯 Used By

This library is used across 17+ repositories:

• AI Assistant + Vector Store Manager
• Excel Operations Processor
• Email Ingestion Service
• HITL Review Service
• ... (13 more Azure Functions projects)

📋 Requirements

Runtime Requirements

• Python 3.11+
• Azure subscription with:
  • Azure App Configuration (optional)
  • Azure Key Vault (optional)
  • Application Insights (optional)

Dependencies

azure-appconfiguration-provider >= 1.0.0
azure-keyvault-secrets >= 4.7.0
azure-identity >= 1.15.0
azure-monitor-opentelemetry >= 1.2.0
opentelemetry-api >= 1.22.0
opentelemetry-instrumentation-azure-functions >= 0.45b0

⭐ Key Benefits

For the Organization

• ✅ Single Source of Truth - One codebase for 17+ projects
• ✅ Consistent Behavior - Same bootstrap logic everywhere
• ✅ Easy Maintenance - Fix bugs once, benefit everywhere
• ✅ Version Control - Semantic versioning with changelogs

For Developers

• ✅ Simple Integration - Just pip install and 2-line import
• ✅ No Implementation Knowledge - Use public API, done
• ✅ Type-Safe - Full type hints for IDE support
• ✅ Well-Tested - 80%+ coverage, production-proven

For Operations

• ✅ Centralized Updates - Deploy improvements once
• ✅ Reduced Duplication - No copy-paste errors
• ✅ Better Monitoring - Consistent telemetry
• ✅ Easier Debugging - Same code across projects

📄 License

MIT License - See LICENSE for details.

🆘 Support

• Repository: https://github.com/TheViziusGroup/azure-bootstrap
• Issues: https://github.com/TheViziusGroup/azure-bootstrap/issues
• PyPI: https://pypi.org/project/azure-bootstrap/

Ready to get started? Install the library and see examples/function_app_example.py for a complete working example!