dockcheck

A script checking updates for docker images without the need of pulling - then having the option to auto-update.

With the help of regctl.
This is just a concept for fun and inspiration, use with care.

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Dependencies:

Running docker (duh) and compose, either standalone or plugin.
regctl by regclient
The script will ask to download regctl if it's not in PATH or current directory.

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dockcheck.sh

$ ./dockcheck.sh -h
Syntax:     dockcheck.sh [OPTION] [optional string to filter names]

Options:
-h     Print this Help.
-a     Automatic updates, without interaction.
-n     No updates, only checking availability.

Basic example:

$ ./dockcheck.sh
. . .
Containers with updates available:
whoogle-search

Containers on latest version:
glances
homer

Do you want to update? y/[n]
y

Then it proceedes to run pull and up -d on every container with updates.

And with -n No updates and gl for *gl* filtering:

$ ./dockcheck.sh -n gl
. . .
Containers with updates available:
whoogle-search

Containers on latest version:
glances

No updates installed, exiting

🪲 Squashed Bugs:

• No options for running without updates or auto update.
• No filter to check only specific containers.
• Faulty registry checkups stopped the updates completely.
• No clear checks to skip containers producing errors.
• Multi-digest images didn't correctly check with registry, giving false positives on updates.

🔨 Known issues

• No granular choice of what to update (except initial name filter).
• No detailed error feedback (just skip + list what's skipped) .

dockcheck_docker-run_ver.sh

Alternative version for people who use docker run and no composes. Consider that this will restart updated containers without taking into account any other containers relying or depending on said container - might need to restart relating containers afterwards.

dupc_function.sh

Function to quickly check for updates on a single contianer or list of containers by name. Without the need of pulling.
Preferably placed in .bashrc or similar. Example:

$ dupc ng
Updates available for local_nginx.
nginx_reverse is already latest.
Updates available for paperless-ng.