oasist 0.1.3

OASist Client Generator: generate Python clients from OpenAPI schemas

OASist Client Generator

Automated Python client generation from OpenAPI schemas. Simple, clean, and efficient.

Features

• 🚀 Single-file implementation (no complexity)
• 📦 Generate type-safe Python clients from OpenAPI specs
• 🔄 Easy client updates and management
• 🎯 CLI interface for all operations
• 🏗️ Built with design patterns (Factory, Command)

Installation

# Install from PyPI
pip install oasist-client

Quick Start

# List all configured services
oasist list

# Generate a specific client
oasist generate user

# Generate all clients
oasist generate-all

# Show service details
oasist info user

# Force regenerate existing client
oasist generate user --force

Configuration

Configuration

The generator supports both JSON and YAML OpenAPI documents. It pre-fetches the schema with optional headers/params, then generates via a local temp file to ensure consistent handling of JSON and YAML. Configuration is provided via a single JSON file.

Create oasist_config.json in your project root:

{
  "output_dir": "./clients",
  "services": [
    {
      "key": "public_json",
      "name": "Public JSON API",
      "schema_url": "http://91.99.51.233:8001/openapi.json",
      "output_dir": "public_json_client",
      "base_url": "",
      "package_name": "",
      "prefer_json": true
    },
    {
      "key": "local_yaml",
      "name": "Local YAML API",
      "schema_url": "http://localhost:8004/api/schema/",
      "output_dir": "local_yaml_client",
      "base_url": "http://localhost:8004",
      "package_name": "",
      "prefer_json": true,
      "request_headers": {
        "Accept": "application/vnd.oai.openapi+json, application/json"
      }
    }
  ]
}

Configuration Parameters

Parameter	Required	Description
output_dir	No	Base directory for all generated clients
services	Yes	Array of service configurations
key	Yes	Unique identifier for the service
name	Yes	Human-readable service name
schema_url	Yes	URL to OpenAPI schema endpoint
output_dir	Yes	Directory name for generated client
base_url	No	Service base URL (auto-detected if not provided)
package_name	No	Python package name (auto-generated if not provided)
request_headers	No	Extra HTTP headers for schema fetch (e.g., Accept)
request_params	No	Extra query parameters for schema fetch
prefer_json	No	If true, sets Accept to prefer OpenAPI JSON

ServiceConfig Parameters

Parameter	Required	Description
name	Yes	Human-readable service name
schema_url	Yes	URL to OpenAPI schema endpoint
output_dir	Yes	Directory name for generated client
base_url	No	Service base URL (auto-detected if not provided)
package_name	No	Python package name (auto-generated if not provided)

Usage in Code

# Import the generated client
from clients.user_service.user_service_client import Client

# Initialize client
client = Client(base_url="http://192.168.100.11:8011")

# Use the client
response = client.users.list_users()
user = client.users.get_user(user_id=123)

All Commands

Basic Commands

# Show general help
oasist --help
oasist help

# Show command-specific help
oasist help generate
oasist generate --help

# List all services and their generation status
oasist list

# Show detailed information about a service
oasist info <service_name>

Generation Commands

# Generate client for a specific service
oasist generate <service_name>

# Force regenerate (overwrite existing)
oasist generate <service_name> --force

# Generate clients for all configured services
oasist generate-all

# Generate all with force overwrite
oasist generate-all --force

Update Commands

# Update existing client (alias for generate --force)
python oasist.py generate <service_name> --force

Project Structure

oasist/
├── oasist.py       # Single-file generator (all-in-one)
├── README.md               # This file
├── .gitignore             # Git ignore rules
└── clients/               # Generated clients directory
    ├── user_service/      # Generated client example
    │   ├── pyproject.toml
    │   └── user_service_client/
    │       ├── __init__.py
    │       ├── client.py
    │       ├── api/
    │       ├── models/
    │       └── types.py
    └── [other_services]/  # Additional generated clients

Requirements

• Python 3.8+
• openapi-python-client
• requests
• pyyaml

Troubleshooting

Schema URL not accessible

Ensure the service is running and the schema endpoint is correct:

curl http://192.168.100.11:8011/api/schema/

Permission errors

Ensure write permissions for the clients directory:

chmod -R u+w clients/

Client generation fails

Check if openapi-python-client is installed:

pip install --upgrade openapi-python-client

Enable debug logging in code:

logging.basicConfig(level=logging.DEBUG)

Design Patterns Used

• Factory Pattern: ClientGenerator creates configured clients
• Command Pattern: CLI commands encapsulate operations
• Dataclass Pattern: Immutable configuration objects
• Singleton Pattern: Single generator instance manages all services

Django Integration (Optional)

To use with Django management commands:

# In your Django management command
from oasist import ClientGenerator, ServiceConfig

generator = ClientGenerator(output_base=Path("./clients"))
generator.add_service("user", ServiceConfig(...))
generator.generate("user")

Advanced Usage

Programmatic Usage

from oasist import ClientGenerator, ServiceConfig
from pathlib import Path

# Create generator with custom output directory
generator = ClientGenerator(output_base=Path("./my_clients"))

# Add services
generator.add_service("api", ServiceConfig(
    name="API Service",
    schema_url="https://api.example.com/openapi.json",
    output_dir="api_client"
))

# Generate
generator.generate("api", force=True)

# Or generate all
generator.generate_all(force=True)

# Note: You can also modify the OUTPUT_DIR constant at the top of the file
# for persistent changes instead of passing output_base parameter

Custom Base URL

generator.add_service("prod", ServiceConfig(
    name="Production API",
    schema_url="https://api.example.com/schema/",
    output_dir="prod_client",
    base_url="https://api.example.com"  # Custom base URL
))

Examples

Example 1: Generate User Service Client

$ oasist generate user
INFO: ✓ Generated client: user → clients/user_service

Example 2: List All Services

$ oasist list

📋 Configured Services:
  ✓ user                User Service                  http://192.168.100.11:8011/api/schema/
  ○ payment             Payment Service               http://192.168.100.11:8012/api/schema/

Example 3: Service Information

$ oasist info user

📦 Service: user
   Name:        User Service
   Schema URL:  http://192.168.100.11:8011/api/schema/
   Output:      clients/user_service
   Status:      Generated ✓
   Modified:    2025-10-05 14:30:22

Contributing

This is a single-file tool designed for simplicity. To extend:

1. Add services in the main() function
2. Modify ClientGenerator class for custom behavior
3. Add new commands in the command handling section

License

MIT License - Part of the project

Support

For issues or questions:

• Check the Troubleshooting section
• Review the OpenAPI schema URL accessibility
• Verify all dependencies are installed
• Enable debug logging for detailed error information