On 01/09, Jonathan Tan wrote: > On Tue, 9 Jan 2018 14:16:42 -0800 > Brandon Williams <bmwill@xxxxxxxxxx> wrote: > > > All good documentation changes. > > Thanks! > > > > > + /* > > > > + * Function called when a client requests the capability as a command. > > > > + * The command request will be provided to the function via 'keys', the > > > > + * capabilities requested, and 'args', the command specific parameters. > > > > + * > > > > + * This field should be NULL for capabilities which are not commands. > > > > + */ > > > > + int (*command)(struct repository *r, > > > > + struct argv_array *keys, > > > > + struct argv_array *args); > > > > > > Looking at the code below, I see that the command is not executed unless > > > advertise returns true - this means that a command cannot be both > > > supported and unadvertised. Would this be too restrictive? For example, > > > this would disallow a gradual across-multiple-servers rollout in which > > > we allow but not advertise a capability, and then after some time, > > > advertise the capability. > > > > One way to change this would be to just add another function to the > > struct which is called to check if the command is allowed, instead of > > relying on the same function to do that for both advertise and > > allow...though I don't see a big win for allowing a command but not > > advertising it. > > My rationale for allowing a command but not advertising it is in the > paragraph above (that you quoted), but if that is insufficient > rationale, then I agree that we don't need to do this. I have no issues with adding that functionality, i don't really feel that strongly one way or another. Just seemed like additional work for not much gain right now, key being right now. It very well may be worth it for the use case you specified. If so I can definitely make the change. > > > > If we change this, then the value parameter of advertise can be > > > mandatory instead of optional. > > > > I don't see how this fixes the issue you bring up. > > This is a consequence, not a fix - if we were to do as I suggested, then > we no longer need to invoke advertise to check whether something is > advertised except when we are advertising them, in which case "value" > never needs to be NULL. Oh I understand what you are trying to explain, yes you're right. -- Brandon Williams
