dokku/docs/processes/one-off-tasks.md

One-off Tasks

run [-e|--env KEY=VALUE] [--no-tty] <app> <cmd>         # Run a command in a new container using the current app image
run:detached [-e|-env KEY=VALUE] [--no-tty] <app> <cmd> # Run a command in a new detached container using the current app image
run:list [<app>]                                        # List all run containers for an app

Sometimes it is necessary to run a one-off command under an app. Dokku makes it easy to run a fresh container via the run command.

Usage

Running a one-off command

The run command can be used to run a one-off process for a specific command. This will start a new container and run the desired command within that container. This contianer will be removed after the process exits. The container image will be the same container image as was used to start the currently deployed app.

# runs `ls -lah` in the `/app` directory of the app `node-js-app`
dokku run node-js-app ls -lah

# optionally, run can be passed custom environment variables
dokku run --env "NODE_ENV=development" --env "PATH=/custom/path" node-js-app npm run mytask

Running Procfile commands

The run command can also be used to run a command defined in the app Procfile:

console: bundle exec racksh

# runs `bundle exec racksh` in the `/app` directory of the app `my-app`
dokku run my-app console

Specifying container labels

Containers may have specific labels attached. In order to avoid issues with dokku internals, do not use any labels beginning with either com.dokku or org.label-schema.

dokku --label=com.example.test-label=value run node-js-app ls -lah

Disabling TTY

One-off containers default to interactive mode where possible. To disable this behavior, specify the --no-tty flag:

dokku run --no-tty node-js-app ls -lah

Running a detached container

Finally, a container can be run in "detached" mode via the run:detached Dokku command. Running a process in detached mode will immediately return a CONTAINER_ID. It is up to the user to then further manage this container in whatever manner they see fit, as Dokku will not automatically terminate the container.

dokku run:detached node-js-app ls -lah
# returns the ID of the new container

Listing one-off containers

One-off containers for a given app can be listed via the run:list command:

dokku run:list node-js-app

=====> node-js-app run containers
NAMES                   COMMAND            CREATED
node-js-app.run.28689   "/exec sleep 15"   2 seconds ago

The COMMAND displayed will be what Docker executes and may not exactly match the command specified by a dokku run command.