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.
When triggering
dokku ps:rebuild APP
on an application deployed via thetags
plugin, the following may occur:
- Applications previously deployed via another method (
git
/tar
): The application may revert to a state before the latest custom image tag was deployed.- Applications that were only ever deployed via the
tags
plugin: No action will be taken against your application.Please use the
tags:deploy
command when redeploying an application deployed via docker image.
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.
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
> node-js-app@0.1.0 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
-----> Running nginx-pre-reload
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 app 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
Deploy tag
dokku tags:deploy test-app v12
Note: When deploying an image, we will use
docker inspect
to extract theExposedPorts
configuration and if defined, use that to populateDOKKU_DOCKERFILE_PORTS
. If this behavior is not desired, you can override that configuration variable with theconfig:set
command. Example:dokku config:set test-app DOKKU_DOCKERFILE_PORTS="5984/tcp 80/tcp"
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 && dokku tags:create test-app latest"