d6ea4b4139
...to work for specific edge cases with a simpler solution. Re-reads hooks directories after any changes are detected by the watchers. Added monitoring test for adding a different invalid hook to primary directory. Some issues with prior code: - ReadDir would stop when it encounters an invalid hook, rather than registering an error but continuing to read the valid hook. - Wouldn’t account for Rename and Chmod events. - After doing a mv of the hooks file instead of rm, it would still think the hooks file is in the directory, but it has been moved to another location. - If a hook file was renamed, it would register the renamed file as a separate hook and not delete the original, so it would then execute the hook twice - once for the renamed file, and once for the original name which it did not delete. Signed-off-by: samc24 <sam.chaturvedi24@gmail.com> |
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| .. | ||
| 0.1.0 | ||
| 1.0.0 | ||
| docs | ||
| exec | ||
| README.md | ||
| hooks.go | ||
| hooks_test.go | ||
| monitor.go | ||
| monitor_test.go | ||
| read.go | ||
| read_test.go | ||
| version.go | ||
README.md
OCI Hooks Configuration
For POSIX platforms, the OCI runtime configuration supports hooks for configuring custom actions related to the life cycle of the container.
The way you enable the hooks above is by editing the OCI runtime configuration before running the OCI runtime (e.g. runc).
CRI-O and podman create create the OCI configuration for you, and this documentation allows developers to configure them to set their intended hooks.
One problem with hooks is that the runtime actually stalls execution of the container before running the hooks and stalls completion of the container, until all hooks complete.
This can cause some performance issues.
Also a lot of hooks just check if certain configuration is set and then exit early, without doing anything.
For example the oci-systemd-hook only executes if the command is init or systemd, otherwise it just exits.
This means if we automatically enabled all hooks, every container would have to execute oci-systemd-hook, even if they don't run systemd inside of the container.
Performance would also suffer if we exectuted each hook at each stage (pre-start, post-start, and post-stop).
The hooks configuration is documented in oci-hooks.5.