podman/pkg/hooks
Valentin Rothberg bd09b7aa79 bump go module to version 4
Automated for .go files via gomove [1]:
`gomove github.com/containers/podman/v3 github.com/containers/podman/v4`

Remaining files via vgrep [2]:
`vgrep github.com/containers/podman/v3`

[1] https://github.com/KSubedi/gomove
[2] https://github.com/vrothberg/vgrep

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>
2022-01-18 12:47:07 +01:00
..
0.1.0 bump go module to version 4 2022-01-18 12:47:07 +01:00
1.0.0 pkg/hooks: support all hooks 2020-09-22 14:44:09 +02:00
docs [CI:DOCS] oci-hooks.5.md: fixup section in header 2021-10-10 08:16:42 -04:00
exec standardize logrus messages to upper case 2021-09-22 15:29:34 -04:00
hooks.go bump go module to version 4 2022-01-18 12:47:07 +01:00
hooks_test.go bump go module to version 4 2022-01-18 12:47:07 +01:00
monitor.go bump go module to version 4 2022-01-18 12:47:07 +01:00
monitor_test.go Improved hooks monitoring 2019-07-25 09:52:45 -04:00
read.go bump go module to version 4 2022-01-18 12:47:07 +01:00
read_test.go bump go module to version 4 2022-01-18 12:47:07 +01:00
README.md Spelling 2020-12-22 13:34:31 -05:00
version.go pkg/hooks: Version the hook structure and add 1.0.0 hooks 2018-05-11 16:26:35 +00:00

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 executed each hook at each stage (pre-start, post-start, and post-stop).

The hooks configuration is documented in oci-hooks.5.