Compose CLI environment variables

Several environment variables are available for you to configure the Docker Compose command-line behaviour.

Variables starting with DOCKER_ are the same as those used to configure the Docker command-line client. If you’re using docker-machine, then the eval "$(docker-machine env my-docker-vm)" command should set them to their correct values. (In this example, my-docker-vm is the name of a machine you created.)

Note: Some of these variables can also be provided using an environment file

COMPOSE_PROJECT_NAME

Sets the project name. This value is prepended along with the service name to the container on start up. For example, if you project name is myapp and it includes two services db and web then compose starts containers named myapp_db_1 and myapp_web_1 respectively.

Setting this is optional. If you do not set this, the COMPOSE_PROJECT_NAME defaults to the basename of the project directory. See also the -p command-line option.

COMPOSE_FILE

Specify the path to a Compose file. If not provided, Compose looks for a file named docker-compose.yml in the current directory and then each parent directory in succession until a file by that name is found.

This variable supports multiple compose files separate by a path separator (on Linux and macOS the path separator is :, on Windows it is ;). For example: COMPOSE_FILE=docker-compose.yml:docker-compose.prod.yml

See also the -f command-line option.

COMPOSE_API_VERSION

The Docker API only supports requests from clients which report a specific version. If you receive a client and server don't have same version error using docker-compose, you can workaround this error by setting this environment variable. Set the version value to match the server version.

Setting this variable is intended as a workaround for situations where you need to run temporarily with a mismatch between the client and server version. For example, if you can upgrade the client but need to wait to upgrade the server.

Running with this variable set and a known mismatch does prevent some Docker features from working properly. The exact features that fail would depend on the Docker client and server versions. For this reason, running with this variable set is only intended as a workaround and it is not officially supported.

If you run into problems running with this set, resolve the mismatch through upgrade and remove this setting to see if your problems resolve before notifying support.

DOCKER_HOST

Sets the URL of the docker daemon. As with the Docker client, defaults to unix:///var/run/docker.sock.

DOCKER_TLS_VERIFY

When set to anything other than an empty string, enables TLS communication with the docker daemon.

DOCKER_CERT_PATH

Configures the path to the ca.pem, cert.pem, and key.pem files used for TLS verification. Defaults to ~/.docker.

COMPOSE_HTTP_TIMEOUT

Configures the time (in seconds) a request to the Docker daemon is allowed to hang before Compose considers it failed. Defaults to 60 seconds.

COMPOSE_TLS_VERSION

Configure which TLS version is used for TLS communication with the docker daemon. Defaults to TLSv1. Supported values are: TLSv1, TLSv1_1, TLSv1_2.

COMPOSE_CONVERT_WINDOWS_PATHS

Enable path conversion from Windows-style to Unix-style in volume definitions. Users of Docker Machine and Docker Toolbox on Windows should always set this.

Related Information

• User guide
• Installing Compose
• Compose file reference
• Environment file