Users that misconfigure their process's listening interface or port will now see an additional healthcheck warning for web deploys. While only a single port is checked, this ensures that users at least have some context as to why their app isn't responding as expected.
Closes#4798
This change converts existing CHECKS files into a healthchecks key that is understood by 'docker-container-healthchecker'. This tool supports a number of different types of container healthchecks - command, http, uptime - and can perform healthchecks against non-web processes.
The use of the old CHECKS file is now deprecated, and will be removed in the next minor version. Users can use the 'docker-container-healthchecker' to convert existing CHECKS files to the new format automatically.
Closes#2760
This change minimizes the work needed to be done when tagging images. It edits the image manifest directly only when necessary, allowing restarts of an app to avoid having an extra layer.
This also additionally allows to deploy images with ONBUILD directives without running the ONBUILD directives.
Lastly, users building docker images that run Dokku will need to use a new sudoer wrapper for the `docker-image-labeler` binary to work correctly. A reference version has been placed in the `docker` skeleton directory.
Closes#3931
Refs #4226
This change allows supporting the openresty package as installed on Ubuntu 18.04 from the official openresty package repository, while also returning general nginx support.
Closes#3675
