Server restart

[joshmoore]

Commands for more simply restarting individual server components (services). See discussion under #2173 (comment) for the current state of this branch and @sbesson's opinion.

Current usage:

bin/omero admin kill Processor-0  # Restarts the processor

/cc @manics

[manics]

👍 for admin ice shortcuts, agree with @sbesson that kill is misleading though. Are we're making multi-node grid servers a higher priority over the next few months? If so then perhaps we should hold off for a bit.

[joshmoore]

Agreed. No rush on this PR. More API design.

[mtbc]

Label on-hold?

[joshmoore]

@manics / @sbesson / @kennethgillen / et al: time to come back to this? Suggested names?

[kennethgillen]

My gut feeling would be for another parameter, e.g.

bin/omero admin restart does the usual (Blitz, or everything?)
bin/omero admin restart Processor-0 restarts the Processor-0 process

[joshmoore]

Agreed, but that would unfortunately be a breaking change. We could however do:

bin/omero admin restart --service Processor-0

[manics]

Compared to bin/omero admin ice server stop Processor-0 it avoids the mention of ice and is one less word to type, but still requires the potentially confusing --service argument. I'm not sure it's worth it just for this.

[joshmoore]

That sounds like a motion to close? Seconds?

[joshmoore]

No one? (The benefit in terms of keys typed would be that stop --service could also do the disable, I guess)

[manics]

Could we make a semi-breaking change so that omero admin restart XXX behaves as at present if XXX is a valid option, but otherwise attempts to do the ice restart command with a warning? i.e. make the --service argument optional.

[joshmoore]

where XXX is Processor-0 etc? interesting....

[manics]

Maybe also add --target and --file arguments too for completeness, and in the event of ambiguity (i.e. no --argument was passed and there's no matching target/file/server) you either return an error or default to one of those behaviours?

[joshmoore]

@manics, I've pushed an implementation of your suggestion. This may simply be too confusing to be worthwhile. In which case, let's close and move on. 😄

[manics]

Works, though omero restart non-existent unexpectedly restarted the whole server.

[manics]

I'm not sure of the best way forward, short of fixing the "No Processor"

[joshmoore]

Works, though omero restart non-existent unexpectedly restarted the whole server.

Perhaps make omero restart STRING disallowed and just use omero restart --service ?

I'm not sure of the best way forward, short of fixing the "No Processor"

How does this apply?

[manics]

I thought the "No Processor" was the main motivation for wanting this in ASAP #2173 (comment)

[joshmoore]

Ah, I see. Certainly the most frequent use (at the moment), but not the only reason to use these. Code changes etc. require a restart as well.

[joshmoore]

Closing for lack of clarity. If anyone cares sufficiently we can re-open. Otherwise, perhaps a replacement launching strategy will make it all simpler anyway.