types.EventHandler.Name is currently restricted to "pre-start" and "post-stop"

[vcaputo]

The spec doesn't seem to state anywhere that these are the only two valid eventHandler names, but the implementation enforces it.

Is there any reason for this? any reason to not make the name an ACName type, and only give meaning to "pre-start" and "post-stop" in the spec, but let implementations honor others as they see fit?

[jonboulle]

The spec does say it (I can't link to the exact part but it is in the image manifest schema):

must be one of:
pre-start - executed and must exit before the long running main exec binary is launched
post-stop - executed if the main exec process is killed. This can be used to cleanup resources in the case of clean application shutdown, but cannot be relied upon in the face of machine failure.

I am going to say this is covered by #58 (see last comment there)