docker
/
docs
mirror of https://github.com/docker/docs.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity
docs/compose/compose-file/compose-file-v1.md

515 lines
15 KiB
Markdown
Raw Blame History

---
description: Compose file reference
keywords: fig, composition, compose version 1, docker
redirect_from:
- /compose/yml
title: Compose file version 1 reference
toc_max: 4
toc_min: 1
---
These topics describe version 1 of the Compose file format. This is the oldest
version.
For a Compose/Docker Engine compatibility matrix, and detailed guidelines on
versions and upgrading, see
[Compose file versions and upgrading](compose-versioning.md).
## Service configuration reference
The Version 1 Compose file is a [YAML](http://yaml.org/) file that defines [services](#service-configuration-reference).
The default path for a Compose file is `./docker-compose.yml`.
>**Tip**: You can use either a `.yml` or `.yaml` extension for this file. They both work.
A service definition contains configuration which will be applied to each
container started for that service, much like passing command-line parameters to
`docker run`.
As with `docker run`, options specified in the Dockerfile (e.g., `CMD`,
`EXPOSE`, `VOLUME`, `ENV`) are respected by default - you don't need to
specify them again in `docker-compose.yml`.
This section contains a list of all configuration options supported by a service
definition in version 1.
### build
Configuration options that are applied at build time.
`build` can specified as a string containing a path to the build
context.
build: ./dir
> **Note**: In the [version 1 file format](compose-versioning.md#version-1), `build` is different in
> two ways:
>
> 1. Only the string form (`build: .`) is allowed - not the object form that is allowed in Version 2 and up.
> 2. Using `build` together with [`image`](#image) is not allowed. Attempting to do so
> results in an error.
#### dockerfile
Alternate Dockerfile.
Compose will use an alternate file to build with. A build path must also be
specified.
build: .
dockerfile: Dockerfile-alternate
> **Note**: In the [version 1 file format](compose-versioning.md#version-1), `dockerfile` is
> different from newer versions in two ways:
>
> 1. It appears alongside `build`, not as a sub-option:
>
> 2. Using `dockerfile` together with [`image`](#image) is not allowed. Attempting to do so results in an error.
### cap_add, cap_drop
Add or drop container capabilities.
See `man 7 capabilities` for a full list.
cap_add:
- ALL
cap_drop:
- NET_ADMIN
- SYS_ADMIN
> **Note**: These options are ignored when
> [deploying a stack in swarm mode](/engine/reference/commandline/stack_deploy.md)
> with a (version 3) Compose file.
### command
Override the default command.
command: bundle exec thin -p 3000
The command can also be a list, in a manner similar to
[dockerfile](/engine/reference/builder.md#cmd):
command: [bundle, exec, thin, -p, 3000]
### cgroup_parent
Specify an optional parent cgroup for the container.
cgroup_parent: m-executor-abcd
### container_name
Specify a custom container name, rather than a generated default name.
container_name: my-web-container
Because Docker container names must be unique, you cannot scale a service
beyond 1 container if you have specified a custom name. Attempting to do so
results in an error.
### devices
List of device mappings. Uses the same format as the `--device` docker
client create option.
devices:
- "/dev/ttyUSB0:/dev/ttyUSB0"
### dns
Custom DNS servers. Can be a single value or a list.
dns: 8.8.8.8
dns:
- 8.8.8.8
- 9.9.9.9
### dns_search
Custom DNS search domains. Can be a single value or a list.
dns_search: example.com
dns_search:
- dc1.example.com
- dc2.example.com
### entrypoint
Override the default entrypoint.
entrypoint: /code/entrypoint.sh
The entrypoint can also be a list, in a manner similar to
[dockerfile](/engine/reference/builder.md#entrypoint):
entrypoint:
- php
- -d
- zend_extension=/usr/local/lib/php/extensions/no-debug-non-zts-20100525/xdebug.so
- -d
- memory_limit=-1
- vendor/bin/phpunit
> **Note**: Setting `entrypoint` will both override any default entrypoint set
> on the service's image with the `ENTRYPOINT` Dockerfile instruction, *and*
> clear out any default command on the image - meaning that if there's a `CMD`
> instruction in the Dockerfile, it will be ignored.
### env_file
Add environment variables from a file. Can be a single value or a list.
If you have specified a Compose file with `docker-compose -f FILE`, paths in
`env_file` are relative to the directory that file is in.
Environment variables specified in `environment` override these values.
env_file: .env
env_file:
- ./common.env
- ./apps/web.env
- /opt/secrets.env
Compose expects each line in an env file to be in `VAR=VAL` format. Lines
beginning with `#` (i.e. comments) are ignored, as are blank lines.
# Set Rails/Rack environment
RACK_ENV=development
> **Note**: If your service specifies a [build](#build) option, variables
> defined in environment files will _not_ be automatically visible during the
> build.
The value of `VAL` is used as is and not modified at all. For example if the value is
surrounded by quotes (as is often the case of shell variables), the quotes will be
included in the value passed to Compose.
### environment
Add environment variables. You can use either an array or a dictionary. Any
boolean values; true, false, yes no, need to be enclosed in quotes to ensure
they are not converted to True or False by the YML parser.
Environment variables with only a key are resolved to their values on the
machine Compose is running on, which can be helpful for secret or host-specific values.
environment:
RACK_ENV: development
SHOW: 'true'
SESSION_SECRET:
environment:
- RACK_ENV=development
- SHOW=true
- SESSION_SECRET
> **Note**: If your service specifies a [build](#build) option, variables
> defined in `environment` will _not_ be automatically visible during the
> build.
### expose
Expose ports without publishing them to the host machine - they'll only be
accessible to linked services. Only the internal port can be specified.
expose:
- "3000"
- "8000"
### extends
Extend another service, in the current file or another, optionally overriding
configuration.
You can use `extends` on any service together with other configuration keys.
The `extends` value must be a dictionary defined with a required `service`
and an optional `file` key.
extends:
file: common.yml
service: webapp
The `service` the name of the service being extended, for example
`web` or `database`. The `file` is the location of a Compose configuration
file defining that service.
If you omit the `file` Compose looks for the service configuration in the
current file. The `file` value can be an absolute or relative path. If you
specify a relative path, Compose treats it as relative to the location of the
current file.
You can extend a service that itself extends another. You can extend
indefinitely. Compose does not support circular references and `docker-compose`
returns an error if it encounters one.
For more on `extends`, see the
[the extends documentation](/compose/extends.md#extending-services).
### external_links
Link to containers started outside this `docker-compose.yml` or even outside
of Compose, especially for containers that provide shared or common services.
`external_links` follow semantics similar to `links` when specifying both the
container name and the link alias (`CONTAINER:ALIAS`).
external_links:
- redis_1
- project_db_1:mysql
- project_db_1:postgresql
### extra_hosts
Add hostname mappings. Use the same values as the docker client `--add-host` parameter.
extra_hosts:
- "somehost:162.242.195.82"
- "otherhost:50.31.209.229"
An entry with the ip address and hostname will be created in `/etc/hosts` inside containers for this service, e.g:
162.242.195.82 somehost
50.31.209.229 otherhost
### image
Specify the image to start the container from. Can either be a repository/tag or
a partial image ID.
image: redis
image: ubuntu:14.04
image: tutum/influxdb
image: example-registry.com:4000/postgresql
image: a4bc65fd
If the image does not exist, Compose attempts to pull it, unless you have also
specified [build](#build), in which case it builds it using the specified
options and tags it with the specified tag.
> **Note**: In the [version 1 file format](compose-versioning.md#version-1), using [`build`](#build) together
> with `image` is not allowed. Attempting to do so results in an error.
### labels
Add metadata to containers using [Docker labels](/engine/userguide/labels-custom-metadata.md). You can use either an array or a dictionary.
It's recommended that you use reverse-DNS notation to prevent your labels from conflicting with those used by other software.
labels:
com.example.description: "Accounting webapp"
com.example.department: "Finance"
com.example.label-with-empty-value: ""
labels:
- "com.example.description=Accounting webapp"
- "com.example.department=Finance"
- "com.example.label-with-empty-value"
### links
Link to containers in another service. Either specify both the service name and
a link alias (`SERVICE:ALIAS`), or just the service name.
web:
links:
- db
- db:database
- redis
Containers for the linked service will be reachable at a hostname identical to
the alias, or the service name if no alias was specified.
Links also express dependency between services in the same way as
[depends_on](#dependson), so they determine the order of service startup.
> **Note**: If you define both links and [networks](#networks), services with
> links between them must share at least one network in common in order to
> communicate.
### log_driver
> [Version 1 file format](compose-versioning#version-1) only. In version 2 and up, use
> [logging](index.md#logging).
Specify a log driver. The default is `json-file`.
log_driver: syslog
### log_opt
> [Version 1 file format](compose-versioning#version-1) only. In version 2 and up, use
> [logging](index.md#logging).
Specify logging options as key-value pairs. An example of `syslog` options:
log_opt:
syslog-address: "tcp://192.168.0.42:123"
### net
> [Version 1 file format](compose-versioning.md#version-1) only. In version 2 and up, use
> [network_mode](index.md#networkmode) and [networks](index.md#networks).
Network mode. Use the same values as the docker client `--net` parameter.
The `container:...` form can take a service name instead of a container name or
id.
net: "bridge"
net: "host"
net: "none"
net: "container:[service name or container name/id]"
### pid
pid: "host"
Sets the PID mode to the host PID mode. This turns on sharing between
container and the host operating system the PID address space. Containers
launched with this flag will be able to access and manipulate other
containers in the bare-metal machine's namespace and vise-versa.
### ports
Expose ports. Either specify both ports (`HOST:CONTAINER`), or just the container
port (a random host port will be chosen).
> **Note**: When mapping ports in the `HOST:CONTAINER` format, you may experience
> erroneous results when using a container port lower than 60, because YAML will
> parse numbers in the format `xx:yy` as sexagesimal (base 60). For this reason,
> we recommend always explicitly specifying your port mappings as strings.
ports:
- "3000"
- "3000-3005"
- "8000:8000"
- "9090-9091:8080-8081"
- "49100:22"
- "127.0.0.1:8001:8001"
- "127.0.0.1:5000-5010:5000-5010"
- "6060:6060/udp"
### security_opt
Override the default labeling scheme for each container.
security_opt:
- label:user:USER
- label:role:ROLE
### stop_signal
Sets an alternative signal to stop the container. By default `stop` uses
SIGTERM. Setting an alternative signal using `stop_signal` will cause
`stop` to send that signal instead.
stop_signal: SIGUSR1
### ulimits
Override the default ulimits for a container. You can either specify a single
limit as an integer or soft/hard limits as a mapping.
ulimits:
nproc: 65535
nofile:
soft: 20000
hard: 40000
### volumes, volume\_driver
Mount paths or named volumes, optionally specifying a path on the host machine
(`HOST:CONTAINER`), or an access mode (`HOST:CONTAINER:ro`).
For [version 2 files](compose-versioning#version-2), named volumes need to be specified with the
[top-level `volumes` key](compose-file-v2.md#volume-configuration-reference).
When using [version 1](compose-versioning#version-1), the Docker Engine will create the named
volume automatically if it doesn't exist.
You can mount a relative path on the host, which will expand relative to
the directory of the Compose configuration file being used. Relative paths
should always begin with `.` or `..`.
volumes:
# Just specify a path and let the Engine create a volume
- /var/lib/mysql
# Specify an absolute path mapping
- /opt/data:/var/lib/mysql
# Path on the host, relative to the Compose file
- ./cache:/tmp/cache
# User-relative path
- ~/configs:/etc/configs/:ro
# Named volume
- datavolume:/var/lib/mysql
If you do not use a host path, you may specify a `volume_driver`.
volume_driver: mydriver
There are several things to note, depending on which
[Compose file version](compose-versioning#versioning) you're using:
- For [version 1 files](compose-versioning#version-1), both named volumes and
container volumes will use the specified driver.
- No path expansion will be done if you have also specified a `volume_driver`.
For example, if you specify a mapping of `./foo:/data`, the `./foo` part
will be passed straight to the volume driver without being expanded.
See [Docker Volumes](/engine/userguide/dockervolumes.md) and
[Volume Plugins](/engine/extend/plugins_volume.md) for more information.
### volumes_from
Mount all of the volumes from another service or container, optionally
specifying read-only access (``ro``) or read-write (``rw``). If no access level
is specified, then read-write will be used.
volumes_from:
- service_name
- service_name:ro
### cpu\_shares, cpu\_quota, cpuset, domainname, hostname, ipc, mac\_address, mem\_limit, memswap\_limit, mem\_swappiness, privileged, read\_only, restart, shm\_size, stdin\_open, tty, user, working\_dir
Each of these is a single value, analogous to its
[docker run](/engine/reference/run.md) counterpart.
cpu_shares: 73
cpu_quota: 50000
cpuset: 0,1
user: postgresql
working_dir: /code
domainname: foo.com
hostname: foo
ipc: host
mac_address: 02:42:ac:11:65:43
mem_limit: 1000000000
memswap_limit: 2000000000
privileged: true
restart: always
read_only: true
shm_size: 64M
stdin_open: true
tty: true
## Compose documentation
- [User guide](/compose/index.md)
- [Installing Compose](/compose/install/)
- [Compose file versions and upgrading](compose-versioning.md)
- [Get started with Django](/compose/django/)
- [Get started with Rails](/compose/rails/)
- [Get started with WordPress](/compose/wordpress/)
- [Command line reference](/compose/reference/)
Reference in New Issue View Git Blame Copy Permalink