Skip to main content

What is my purpose?

Purpose

As we expand services and go towards microservices architecture, we need to somehow test many databases, that are started and run locally.

Creation, seeding, recreation of database is pretty cumbersome task, which this cli wants to improve.

It uses docker compose under the hood to run specific db instance in containerized fashion, which helps to start service and stop it, fill with info, etc fast.

Here is example, that we will explain, based on corgi-compose.yml postgres example

db_services:
  postgres_with_data_for_go_reactnative:
    driver: postgres
    databaseName: bestDbName
    user: awesomeUser
    password: themostsecurepasswordyoucanimaging
    port: 5511
    seedFromFilePath: ./users_dump.sql

services:
  reactnative_app_get_user:
    cloneFrom: https://github.com/Andriiklymiuk/reactnative_app_get_user.git
    path: ./reactnative_app_get_user
    depends_on_services:
      - name: go_server_user_data
    beforeStart:
      - yarn install
      - npx pod-install
    start:
      - yarn start
      - yarn ios
    afterStart:
      - yarn ios:simulator:close
  go_server_user_data:
    cloneFrom: https://github.com/Andriiklymiuk/go_server_user_data.git
    path: ./go_server_user_data
    port: 7012
    depends_on_db:
      - name: postgres_with_data_for_go_reactnative
        envAlias: none
    start:
      - go run .

required:
  go:
    why:
      - To launch locally go service manually
      - You need to install it yourself brew install go
    checkCmd: go version
  yarn:
    why:
      - To build and launch some of the repos locally with yarn
    install:
      - brew install yarn
    checkCmd: yarn -v
  node:
    why:
      - To build and launch some of the repos locally with npm
    install:
      - brew install node
    checkCmd: node -v
  docker:
    why:
      - To launch databases
      - You need to install it yourself from https://docs.docker.com/desktop/install/mac-install/
    checkCmd: docker -v

What happens on init​

  1. It adds corgi compose files to gitignore
  2. Creates folder with db helpers files in in corgi_services/db_services folder. These files are created, so that you can run db_services manually, if you want.
  3. If the path provided doesn't exist and cloneFrom is provided, than it will run git clone with provided url. So, for example, you provide path to service: ./myWoofServices/corgiserver, than it will run git clone in ./myWoofServices/ folder. Bare in mind, that git clone should create corgiserver folder to correctly work.

What happens on run​

If you run corgi run it will:

  1. Create folder with db helpers files in in corgi_services/db_services folder. These files are created, so that you can run db_services manually, if you want.
  2. If there are any db_services, than it will auto launch docker (if not launched)
  3. If there is --seed flag added, it will get db dump from seedFromFilePath file dump or from seedFromDb or database and populate database
  4. Start databases in docker (docker up)
  5. Check depends_on_db part in each service and it will add env variables (DB_HOST, DB_USER, DB_NAME, DB_PORT ,DB_PASSWORD) for db in the .env file in service path
  6. Check depends_on_service part in each service and it will add env variables for service (server/app, etc) in the .env file in service path in the form of http://localhost:POST_IN_DEPENDENT_SERVICE (in corgiApp it will add http://localhost:8965)
  7. Runs each service concurrently (in parallel)
  • Runs scripts in beforeStart of service
  • Runs scripts in start of service concurrently (in parallel)
  1. If you run Ctrl-C in terminal, it will:
  • terminate all services and their scripts
  • stop all databases
  • runs all afterStart commands

Why GO?​

It is written in GOLANG in order to be: fast and simple, without ton of dependencies. Language isn't that different from javascript of typescript, so it can be used by everyone, can be learnt in one day.

This project is also a proof of concept, that Go is simple, fast and easy to be written, so we can use it to create microservices and write automation.

Pros of using go

  • easy to use and fast to write production level code
  • most things can be done with standard lib itself
  • small (if we remove all fancy staff, then the binary will be around 1mb more or less)
  • makes you think about error handling during coding itself
  • formatting and testing out of the box
  • concurrent from the box (parallel simply speaking) (socket will be cool to write in go)

In short: install go and you are good to go

P.S.: go is not needed to use cli