Moby Ryuk

This project helps you to remove containers, networks, volumes and images by given filter after specified delay.

Building

To build the binary only run:

go build

To build the Linux docker container as the latest tag:

docker build -f linux/Dockerfile -t testcontainers/ryuk:latest .

Usage

To start it using the default settings:

docker run -v /var/run/docker.sock:/var/run/docker.sock -p 8080:8080 testcontainers/ryuk:latest

If you want to test local changes with the default settings:

go run .

You can then simulate a connection from testcontainer container using:

nc -N localhost 8080 << EOF
label=testing=true&label=testing.sessionid=mysession
label=something
EOF

You can send additional session information for monitoring using:

printf "label=something_else" | nc -N localhost 8080

In the ryuk window you'll see containers/networks/volumes deleted after 10s

time=2024-09-30T19:42:30.000+01:00 level=INFO msg=starting connection_timeout=1m0s reconnection_timeout=10s request_timeout=10s shutdown_timeout=10m0s remove_retries=10 retry_offset=-1s changes_retry_interval=1s port=8080 verbose=false
time=2024-09-30T19:42:30.001+01:00 level=INFO msg="Started"
time=2024-09-30T19:42:30.001+01:00 level=INFO msg="client processing started"
time=2024-09-30T19:42:38.002+01:00 level=INFO msg="client connected" address=127.0.0.1:56432 clients=1
time=2024-09-30T19:42:38.002+01:00 level=INFO msg="adding filter" type=label values="[testing=true testing.sessionid=mysession]"
time=2024-09-30T19:42:38.002+01:00 level=INFO msg="adding filter" type=label values=[something]
time=2024-09-30T19:42:38.002+01:00 level=INFO msg="client disconnected" address=127.0.0.1:56432 clients=0
time=2024-09-30T19:42:42.047+01:00 level=INFO msg="adding filter" type=label values=[something_else]
time=2024-09-30T19:42:42.047+01:00 level=INFO msg="client connected" address=127.0.0.1:56434 clients=1
time=2024-09-30T19:42:42.047+01:00 level=INFO msg="client disconnected" address=127.0.0.1:56434 clients=0
time=2024-09-30T19:42:52.051+01:00 level=INFO msg="prune check" clients=0
time=2024-09-30T19:42:52.216+01:00 level=INFO msg="client processing stopped"
time=2024-09-30T19:42:52.216+01:00 level=INFO msg=removed containers=0 networks=0 volumes=0 images=0
time=2024-09-30T19:42:52.216+01:00 level=INFO msg=done

Ryuk configuration

The following environment variables can be configured to change the behaviour:

Environment Variable	Default	Format	Description
RYUK_CONNECTION_TIMEOUT	60s	Duration	The duration without receiving any connections which will trigger a shutdown
RYUK_PORT	8080	uint16	The port to listen on for connections
RYUK_RECONNECTION_TIMEOUT	10s	Duration	The duration after the last connection closes which will trigger resource clean up and shutdown
RYUK_REQUEST_TIMEOUT	10s	Duration	The timeout for any Docker requests
RYUK_REMOVE_RETRIES	10	int	The number of times to retry removing a resource
RYUK_RETRY_OFFSET	-1s	Duration	The offset added to the start time of the prune pass that is used as the minimum resource creation time. Any resource created after this calculated time will trigger a retry to ensure in use resources are not removed
RYUK_CHANGES_RETRY_INTERVAL	1s	Duration	The internal between retries if resource changes (containers, networks, images, and volumes) are detected while pruning
RYUK_VERBOSE	false	bool	Whether to enable verbose aka debug logging
RYUK_SHUTDOWN_TIMEOUT	10m	Duration	The duration after shutdown has been requested when the remaining connections are ignored and prune checks start