Buildpack Deployment
Dokku normally defaults to using heroku buildpacks for deployment, though this may be overridden by committing a valid Dockerfile to the root of your repository and pushing the repository to your Dokku installation. To avoid this automatic Dockerfile deployment detection, you may do one of the following:
- Use
dokku config:setto set theBUILDPACK_URLenvironment variable. - Add
BUILDPACK_URLto a committed.envfile in the root of your repository. - Create a
.buildpacksfile in the root of your repository.
Specifying a custom buildpack
In certain cases you may want to specify a custom buildpack. While dokku uses herokuish to support all the official heroku buildpacks, it is possible that the buildpack detection does not work well for your application. As well, you may wish to use a custom buildpack to handle specific application logic.
To use a specific buildpack, you can run the following dokku command:
# replace APP with the name of your application
# replace REPOSITORY_URL with your buildpack's url
dokku config:set APP BUILDPACK_URL=REPOSITORY_URL
# example: using a specific ruby buildpack version
dokku config:set APP BUILDPACK_URL=https://github.com/heroku/heroku-buildpack-ruby.git#v142
Please check the documentation for your particular buildpack as you may need to include configuration files (such as a Procfile) in your project root.
Using multiple buildpacks
You can only set a single buildpack using the BUILDPACK_URL, though there may be times when you wish to use multiple buildpacks. To do so, simply create a .buildpacks file in the base of your repository. This file should list all the buildpacks, one-per-line. For instance, if you wish to use both the nodejs and ruby buildpacks, your .buildpacks file should contain the following:
https://github.com/heroku/heroku-buildpack-nodejs.git#v87
https://github.com/heroku/heroku-buildpack-ruby.git#v142
Info
Always remember to pin your buildpack versions when using the multi-buildpacks method, or you may find deploys changing your deployed environment.
You may also choose to set just a single buildpack in this file, though that is up to you.
Please check the documentation for your particular buildpack(s) as you may need to include configuration files (such as a Procfile) in your project root.
Using a specific buildpack version
As Dokku pins all buildpacks via herokuish releases, there may be occasions where a local buildpack version is out of date. If you wish to use a more recent version of the buildpack, you may use any of the above methods to specify a buildpack without the git sha attached like so:
# using the latest nodejs buildpack
# replace APP with the name of your application
dokku config:set APP BUILDPACK_URL=https://github.com/heroku/heroku-buildpack-nodejs
You may also wish to use a specific version of a buildpack, which is also simple
# using v87 of the nodejs buildpack
# replace APP with the name of your application
dokku config:set APP BUILDPACK_URL=https://github.com/heroku/heroku-buildpack-nodejs#v87
Clearing buildpack cache
Building containers with buildpacks currently results in a persistent cache directory between deploys. If you need to clear this cache directory for any reason, you may do so by running the following shell command:
Curl Build Timeouts
Certain buildpacks may time out in retrieving dependencies via curl. This can happen when your network connection is poor or if there is significant network congestion. You may see a message similar to gzip: stdin: unexpected end of file after a curl command.
If you see output similar this when deploying , you may need to override the curl timeouts to increase the length of time allotted to those tasks. You can do so via the config plugin: