New as of 0.4.0
tags <app> # List all app image tags tags:create <app> <tag> # Add tag to latest running app image tags:deploy <app> <tag> # Deploy tagged app image tags:destroy <app> <tag> # Remove app image tag
The Dokku tags plugin allows you to add Docker image tags to the currently deployed app image for versioning and subsequent deployment.
dokku ps:rebuild APPon an application deployed via the
tagsplugin, the following may occur:
- Applications previously deployed via another method (
tar): The application may revert to a state before the latest custom image tag was deployed.
- Applications that were only ever deployed via the
tagsplugin: No action will be taken against your application.
Please use the
tags:deploycommand when redeploying an application deployed via Docker image.
See the port management documentation for more information on how Dokku exposes ports for applications and how you can configure these for your app.
For example, you can list all tags for a given application:
dokku tags node-js-app
=====> Image tags for dokku/node-js-app REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE dokku/node-js-app latest 936a42f25901 About a minute ago 1.025 GB
You can also create new tags for that app using the
tags:create function. Tags should conform to the Docker tagging specification for your Docker version. As of 1.10, that specification is available here, while users of older versions can check the documentation here.
dokku tags:create node-js-app v1
=====> Added v1 tag to dokku/node-js-app
Once the tag is created, you can see the output by running the
tags command again.
dokku tags node-js-app
=====> Image tags for dokku/node-js-app REPOSITORY TAG IMAGE ID CREATED VIRTUAL SIZE dokku/node-js-app latest 936a42f25901 About a minute ago 1.025 GB dokku/node-js-app v1 936a42f25901 About a minute ago 1.025 GB
Finally, you can also deploy a local image using the
tags:deploy command. When specifying a tag that is not
latest, the released image will be retagged as the
latest image tag for the app.
Warning: For images based on Herokuish, using the
tags:deploycommand will reset environment variables written into the image, causing a retag to occur. This will - on average - add two extra layers to your deployed image. Note that this does not affect Dockerfile-based images, which are the majority of images deployed via the
dokku tags:deploy node-js-app v1
-----> Releasing node-js-app (dokku/node-js-app:v1)... -----> Deploying node-js-app (dokku/node-js-app:v1)... -----> Running pre-flight checks For more efficient zero downtime deployments, create a file CHECKS. See http://dokku.viewdocs.io/dokku/deployment/zero-downtime-deploys/ for examples CHECKS file not found in container: Running simple container check... -----> Waiting for 10 seconds ... -----> Default container check successful! =====> node-js-app container output: Detected 512 MB available memory, 512 MB limit per process (WEB_MEMORY) Recommending WEB_CONCURRENCY=1 > email@example.com start /app > node index.js Node app is running at localhost:5000 =====> end node-js-app container output -----> Running post-deploy -----> Configuring node-js-app.dokku.me... -----> Creating http nginx.conf Reloading nginx -----> Shutting down old containers in 60 seconds =====> 025eec3fa3b442fded90933d58d8ed8422901f0449f5ea0c23d00515af5d3137 =====> Application deployed: http://node-js-app.dokku.me
You can alternatively add image pulled from a Docker registry and deploy from it by using tagging feature. In this example, we are deploying from Docker Hub.
Create Dokku app as usual.
dokku apps:create test-app
Pull image from Docker Hub.
docker pull demo-repo/some-image:v12
Retag the image to match the created app.
docker tag demo-repo/some-image:v12 dokku/test-app:v12
dokku tags:deploy test-app v12
To ensure your builds are always reproducible, it's considered bad practice to store build artifacts in your repository. For some projects however, building artifacts during deployment to Dokku may affect the performance of running applications.
One solution is to build a finished Docker image on a CI service (or even locally) and deploy it directly to the host running Dokku.
Build image on CI (or locally).
docker build -t dokku/test-app:v12 . # Note: The image must be tagged `dokku/<app-name>:<version>`
Deploy image to Dokku host.
docker save dokku/test-app:v12 | ssh my.dokku.host "docker load | dokku tags:deploy test-app v12"
Note: You can also use a Docker registry to push and pull the image rather than uploading it directly.
Here's a more complete example using the above method:
# build the image docker build -t dokku/test-app:v12 . # copy the image to the dokku host docker save dokku/test-app:v12 | bzip2 | ssh my.dokku.host "bunzip2 | docker load" # tag and deploy the image ssh my.dokku.host "dokku tags:create test-app previous; dokku tags:deploy test-app v12"