Signal docker containers upon filesystem changes. Reacts to changes in the filesystem either via kernel events or by polling in regular intervals. Containers can either be restarted or sent a signal. Suitable for deployment with docker-compose or just docker.
Simply said, this project acts as glue between the filesystem (using the Listen Gem) and Docker (using the Docker-API Gem)
Containers will be queried with every change. Containers started after the monitor will still be notified if they satisfy the query criteria.
Instructions can either be given via commandline arguments or environment variables.
docker run -d --name my-container-notify --mount type=volume,source=examples,destination=/watch --mount type=bind,source=/var/run/docker.sock,destination=/var/run/docker.sock --env NOTIFY_LATENCY=60 container-notify:latest --watch=/watch
| Option | Type | Description | Default Value |
|---|---|---|---|
| -f, --filter PATTERN | Regex | React only to file changes matching the given pattern | All files trigger notifications, exceptions apply * |
| -a, --action ACTION | String | Signal/Action to perform | HUP |
| -d, --delay SECONDS | Float | Time to wait before dispatching notifications | ** |
| -l, --latency SECONDS | Float | Time between checking for changes | ** |
| -v, --[no-]verbose | Bool | Change verbosity for reports about state changes and performed actions | - |
| -c, --compose [PROJECT] | String | Notify containers based on the docker-compose service label value instead of their name | The same project as the container *** |
| -p, --[no-]polling | Poll filesystem for changes instead of listening to events | Bool | - |
| -N, --notify CONTAINER | String | Container (name) to notify upon changes | All containers sharing the same mounts as the current container |
| -W, --watch TARGET | Directory | Mount (directory) to watch for changes | All mounts of the current container |
* The Listen ignores certain files automatically, such as VCS metadata
** Uses the Listen default values, which are different if polling is enabled
*** Using '.' will reduce the search to containers of the same compose project, using '*', will search for every container with the com.docker.compose.service label.
| Environment variable | Commandline equivalent |
|---|---|
| NOTIFY_DELAY | -d |
| NOTIFY_LATENCY | -l |
| CONTAINER_ACTION | -a |
| MOUNT_FILE_FILTER | -f |
| COMPOSE_PROJECT | -c |
| FORCE_POLLING * | -p |
| LOG_VERBOSITY | -v |
* The mere existence of this variable results in the activation of this behaviour
the image is based on the Alpine Linux image from the Docker library.
Docker-Compose is used to create an encapsulated development
environment. After checking out the repo, run
docker-compose run --rm monitor sh to enter the container.
Then, run bundle exec rake spec to run the tests.
The main application can be run with ./bin/container-notify.
The source code from the host is mounted into the container and any change is reflected immediately; you most likely need to stop the application if running (Ctrl+C) and start it again.
Bug reports and pull requests are welcome on GitHub at https://github.com/uip9av6y/container-notify.
The gem is available as open source under the terms of the MIT License.
The Docker image also contain other software which may be under other licenses (such as Bash, etc from the base distribution, along with any direct or indirect dependencies of the primary software being contained). It is the image user's responsibility to ensure that any use of this image complies with any relevant licenses for all software contained within.