Mirror of forum.nim-lang.org

895 :: Getting HTTP timings

• eli (orginal) [2015-02-19T12:08:16+01:00] view original

  I would like to use the AsyncHttpClient to make requests and then get timings for that request, much like you see in browser developer tools or HAR files. The timings would include DNS resolution, Connect, SSL, Send, Wait, and Receive times.

  Since such functionality is not baked in, I wanted to get some ideas on how to accomplish this. My [rough] thoughts right now are I would need to create my own copy of httpclient.nim, asyncdispatch.nim, and perhaps some other modules, and add timers around the dns lookup, socket connect, ssl negotiation, send and read "events". I'm not sure of the exact architecture of where the timings would be stored (perhaps on the socket).

  Any pointers on how this could best be accomplished? Am I missing anything?

---

• dom96 (orginal) [2015-02-19T16:39:44+01:00] view original

  I think you are spot on. Unfortunately there is no easier way from what I can tell.

---

• gmpreussner (orginal) [2015-02-19T17:26:28+01:00] view original

  That sounds like a good use case for aspect-oriented programming. I wonder if that could be accomplished with macros.

---

• eli (orginal) [2015-02-19T22:35:49+01:00] view original

  I was thinking this would be really easy if I could override a module's proc. For example, if I could override

   connect*(socket: AsyncSocket, address: string, port: Port, af = AF_INET) {.async.}
  Run

  in asyncnet.nim, it would be pretty trivial for me to add some timers. Is such a thing possible?

---

• dom96 (orginal) [2015-02-19T22:43:21+01:00] view original

  Only way to do that is to edit asyncnet.nim

---

• gmpreussner (orginal) [2015-02-20T01:44:40+01:00] view original

  I was thinking more about injecting code into the AST of other procs using macros, but this may not be possible right now, especially across module boundaries. If we had this capability, we could augment existing functionality with other cross-cutting concerns, such as logging and performance monitoring.

---

• Araq (orginal) [2015-02-20T01:47:27+01:00] view original

  @gmpreussner You can do that with term rewriting macros if the module allows for some form of module injection.

---

• gmpreussner (orginal) [2015-02-20T02:06:37+01:00] view original

  Is this hypothetical, or does it actually work? If yes, care to post an example at some point? :)

  I don't think AOP is a silver bullet, but for certain aspects (pun intended), such as logging, monitoring and access control it is fantastic. We could probably have a module with some helper macros that would provide syntactic features similar to AspectJ.

---