└── README.md


/README.md:
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  1 | # Docker-Compose cheat sheet
  2 | A cheet sheat to create you docker-compose.yml
  3 | 
  4 | #cheatsheet #docker #docker-compose
  5 | 
  6 | `version: '3.8'`
  7 | 
  8 | ## Build the image
  9 | 
 10 | ```yaml
 11 | web:
 12 |   # build from Dockerfile
 13 |   build: .
 14 |   # alternative to use a folder with more than one Dockerfile:
 15 |   build:
 16 |     context: ./dir # path to Dockerfile
 17 |     dockerfile: Dockerfile.dev #name of the file
 18 |     target: dev # specify the target in a multi-stage build
 19 |   # build from image
 20 |   image: ubuntu
 21 |   image: ubuntu:14.04
 22 | ```
 23 | ## Init
 24 | Run the service as PID 1. Set this option to true to enable this feature for the service.
 25 | ```yaml
 26 | services:
 27 |   web:
 28 |     image: alpine:latest
 29 |     init: true
 30 | ```
 31 | 
 32 | ## Expose port
 33 | 
 34 | ```yaml
 35 | ports:
 36 |   - "3000"
 37 |   - "8000:80"  # guest:host
 38 | # expose ports to linked services (not to host)
 39 | expose: ["3000"]
 40 | ```
 41 | 
 42 | ### Commands and Entrypoint
 43 | 
 44 | ```yaml
 45 | # command to execute
 46 | command: bundle exec thin -p 3000
 47 | command: [bundle, exec, thin, -p, 3000]
 48 | 
 49 | # override the entrypoint
 50 | entrypoint: /app/start.sh
 51 | entrypoint: [php, -d, vendor/bin/phpunit]
 52 | ```
 53 | 
 54 | ### Environment variables
 55 | 
 56 | ```yaml
 57 | # environment vars
 58 | environment:
 59 |   RACK_ENV: development
 60 | environment:
 61 |   - RACK_ENV=development
 62 | 
 63 | # environment vars from file
 64 | env_file: .env
 65 | env_file: [.env, .development.env]
 66 | ```
 67 | 
 68 | ## Health check
 69 | 
 70 | ```yaml
 71 | # declare service healthy when `test` command succeed
 72 | healthcheck:
 73 |   test: ["CMD", "curl", "-f", "http://localhost"]
 74 |   interval: 1m30s
 75 |   timeout: 10s
 76 |   retries: 3
 77 |   start_period: 40s
 78 | ```
 79 | 
 80 | ### Dependencies
 81 | 
 82 | ```yaml
 83 | # make sure `db` is alive before starting
 84 | depends_on:
 85 |   - db
 86 | 
 87 | 
 88 | # make sure `db` is healty before starting
 89 | # and db-init completed without failure
 90 | depends_on:
 91 | db:
 92 |   condition: service_healthy
 93 | db-init:
 94 |   condition: service_completed_successfully
 95 | 
 96 | ```
 97 | 
 98 | ## Volumes
 99 | 
100 | ```yaml
101 | volumes:
102 |   - /var/lib/mysql # anonimous volume
103 |   - ./host_path:/docker_container_path # bind mount
104 | ```
105 | ```yaml
106 | volumes:
107 |   - type: bind
108 |     source: ./host_path
109 |     target: /docker_container_path
110 |   - type: volume
111 |     # no source. Override the previous volumes for a specific path 
112 |     target: /node_modules
113 | ```
114 | 
115 | ## Restart
116 | 
117 | ```yaml
118 | # automatically restart container
119 | restart: unless-stopped
120 | # always, on-failure, no (default)
121 | ```
122 | 
123 | ## User
124 | 
125 | ```yaml
126 | # specifying user
127 | user: root
128 | ```
129 | 
130 | ```yaml
131 | # specifying both user and group with ids
132 | user: 0:0
133 | ```
134 | ## Commands
135 | ``` shell
136 | # Starts existing containers.
137 | docker-compose start
138 | 
139 | # Stops running containers.
140 | docker-compose stop
141 | 
142 | # Pauses running containers.
143 | docker-compose pause
144 | 
145 | # Unpauses paused.
146 | docker-compose unpause
147 | 
148 | # Lists containers.
149 | docker-compose ps
150 | 
151 | # Builds, (re)creates, starts, and attaches to containers for a service.
152 | docker-compose up
153 | 
154 | # Stops and removes containers.
155 | docker-compose down
156 | ```
157 | 
158 | 
159 | Based on https://devhints.io/docker-compose
160 | 


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