Add simple ResponseTiming middleware and test
#2205
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- Uses implicit `Clock[F]` to time from headers parsed to response started - Adds "X-Response-Time" header to `Response`
| resp <- http(req) | ||
| after <- clock.monotonic(timeUnit) | ||
| header = Header(headerName.value, s"${after - before}") | ||
| } yield resp.copy(headers = resp.headers.put(header)) |
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this could be
| } yield resp.copy(headers = resp.headers.put(header)) | |
| } yield resp.withHeaders(resp.headers.put(header)) |
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I don't think there is a withHeaders available. I can do something like this:
} yield resp.putHeaders(resp.headers.put(header).toList:_*)Do you think that's better?
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Ah, it apparently only is on Request. Keep it as .copy, that's fine.
@rossabaker @ChristopherDavenport Why is .withHeaders only on Request? The headers field is the same on both Request and Response.
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Seems like an oversight to me.
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Looks like putHeaders was enough.
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Thanks!
I'm busy with blaze and test stability, so I'm relying others to review the code. |
| * @param timeUnit the units of measure for this timing | ||
| * @param headerName the name to use for the header containing the timing info | ||
| */ | ||
| def apply[F[_]: Sync]( |
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Consistency observation: Most of our middlewares are apply(arg1: Blah, arg2: Foo)(http: HttpApp[F]), so the HttpApp is in the final argument list. Since most of them take implicit constraints, I also don't know how much that convention actually helps us in terms of partial application.
We also usually don't use context bounds when there are other implicits: I would move Sync into the list ahead of clock.
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If I change the arg list, then application looks a bit weird because of the default arguments:
val app = ResponseTiming()(thisService)So I tried to follow EntityLimiter in this case. But I'm happy to change it to whichever is preferred.
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Ooh, that's a good point. My convention breaks down when everything else has a default argument. I dislike having two conventions, but I think yours is better in this case. Objection withdrawn.
- Add clarifying language
Clock[F]to time from headers parsed to response startedResponse, named "X-Response-Time" by defaultFor #2014