On Fri, Jul 29, 2016 at 06:20:51PM +0200, Lars Schneider wrote: > >> That being said a "fail" response is a very good idea! This allows > >> the filter to communicate to git that a non required filter process > >> failed. I will add that to the protocol. Thanks :) > > > > Maybe just send "ok <size>", "ok -1" (for streaming), or "fail <reason>" > > followed by the content? That is similar to other Git protocols, though > > I am not sure they are good models for sanity or extensibility. :) > > > > I don't know if you would want to leave room for other "headers" in the > > response, but you could also do something more HTTP-like, with a status > > code, and arbitrary headers. And presumably git would just ignore > > headers it doesn't know about. I think that's what Jakub's example was > > leaning towards. I'm just not sure what other headers are really useful, > > but it does leave room for extensibility. > > Well, "ok <size>" wouldn't make much sense as we already transmitted > the size upfront I think. Right now I have implemented the following options: Maybe I'm confused about where in the protocol we are. I was imagining: git> smudge git> <filename> git> <size> git> ...pkt-lines... git> pktline-flush git< ok <size> git< ...pkt-lines... git< flush That is, we should say "I have something for you" or "I do not" before sending a size, because in the "I do not" case we have no size to send. A more extensible protocol might look like: git> smudge git> filename=<filename> git> size=<size> git> pktline-flush git> ...pkt-lines of data... git> pktline-flush git< ok (or success, or whatever status code you like) git< size=<size> git< pkt-line-flush git< ...pkt-lines of data... git< pktline-flush That leaves room for new "keys" to be added before the first pkt-flush, without having to change the parsing at all. > "success\n" --> everything was alright > "reject\n" --> the filter rejected the operation but this is no error > if "filter.<driver>.required = false" > <anything else> --> failure that stops/restarts the filter process > > I don't think sending any failure reason makes sense because if a failure > happens then we are likely in a bad state already (that's why I restart the > filter process. I think the filter can report trouble on its own via stdout, > no? I think this is what Git-LFS already does. Git-LFS sends to stderr because there's no other option. I wonder if it would be nicer to make it Git's responsibility to talk to the user, because then it could respect things like "--quiet". I guess error messages are generally printed regardless of verbosity, though, so printing them unconditionally is OK. -Peff -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html