Python Micro Service Example Project

1. Architecture

1.1 Overview

Pymsboot includes 2 separated services:

• pymsboot-api
  • API Gateway
  • Interact with pymsboot-engine by RPC through RabbitMQ
  • Support multi process in one instance by Eventlet + Multiprocess
  • Support scale out to multi instances
• pymsboot-engine
  • Listening RPC message from RabbitMQ as RPC Server
  • Interact with Database
  • Support multi process in one instance by Eventlet + Multiprocess
  • Support scale out to multi instances

Pymsboot refer to OpenStack architecture which has been proved by thousands of production deployments in past years. Follow OpenStack projects could be a good reference:

• Magnum
• Ironic
• Zun

1.2 Configuration

This project use oslo_config to manage the project configuration.

• Prerequisite Install this project by follow command

  python setup.py install
  

  To clean the installation, use python setup.py clean --all

• Generate original conf file

  oslo-config-generator \
  --namespace pymsboot.config \
  --namespace oslo.config \
  --namespace oslo.log \
  --namespace oslo.messaging \
  --namespace oslo.service.wsgi
  

• Frequently used configuration

  [DEFAULT]
  transport_url = rabbit://guest:[email protected]:5672//
  
  [api]
  #host = 0.0.0.0
  #port = 9666
  api_workers = 2
  
  [database]
  connection = postgresql+psycopg2://user:pass@addr:port/db_name
  
  [engine]
  #host = 0.0.0.0
  #topic = pymsboot_engine
  engine_workers = 1
  

2. Deployment

Currently 2 methods are recommended for pymsboot deployment and testing. Container based deployment should be used for production.

2.1 Start Pymsboot by Script

• Start RabbitMQ

  docker run -d --restart=always --name rabbitmq --hostname rabbitmq -p 4369:4369 -p 5671:5671 -p 5672:5672 -p 25672:25672 -p 15671:15671 -p 15672:15672 -e RABBITMQ_DEFAULT_USER=guest -e RABBITMQ_DEFAULT_PASS=guest rabbitmq:3.7.6-management-alpine
  

• Start Pymsboot Engine Service

  # cd to project folder
  python start_engine.py --config-file=conf/pymsboot.conf
  

• Start Pymsboot API Service

  # cd to project folder
  python start_api.py --config-file=conf/pymsboot.conf
  

2.2 Start Pymsboot by Docker

• Start RabbitMQ

  # cd to project folder
  docker-compose -f compose/rabbitmq.yml up -d
  

• Prepare ENV (One-time)

  # cd to project folder
  mkdir -p /etc/pymsboot
  mkdir -p /var/log/pymsboot
  cp conf/pymsboot.conf /etc/pymsboot
  

  • Edit /etc/pymsboot according to your ENV.
  • Edit compose/pymsboot.yml according to yoyr ENV
• Start Pymsboot

  # cd to project folder
  docker-compose -f compose/pymsboot.yml up -d
  

2.3 Log Rotation

Linux system logrotate should be used for log rotate for production.

# cd to project folder
cp resources/pymsboot_log_rotate /etc/logrotate.d/

3. Restful API Server

URL	Method	Usage
/api/v1/movie	GET	Get all movies information
/api/v1/movie	POST	Add one new movie and download it
/api/v1/movie/	GET	Get one movie information by UUID
/api/v1/movie/	PUT	Update one movie information by UUID
/api/v1/movie/	DELETE	Delete one movie information by UUID