Configurable of timeout for API endpoints

[McSurf84]

Improvement

The timeout should be configurable for API endpoints via franklin configuration options.

Notes + Context

Example:I try to create a mosaic with more than 100 items, but after 30 seconds the mosaic creation request is canceled (503 Server Error: Service Unavailable).
@jisantuc mentioned two possibilities in gitter:

• add configuration option
• move the histogram calculations to a background process and expose the status of histogramm creation via websocket

Original conversation:
Ralf Wohlfahrt @McSurf84 Aug. 31 16:35
Can I increase the timeout of the franklin application? I try to create a mosaic with more than 100 items, but after 30 seconds the mosaic creation request is canceled (503 Server Error: Service Unavailable).

James Santucci @jisantuc:matrix.org [m] Aug. 31 17:02
not right now, but that's a pretty easy configuration option to add. can you open an issue? i'll add it to the first release milestone. right now we don't configure the timeout at all. another thing that's pretty easy to do is to move the histogram calculations to a background process. i didn't do that initially because it means the response will have to be a 202 and you'll have to learn that the histograms are "ready" somehow, but if you have some expectations about that information it's also not that difficult. the server could expose a websocket under the mosaic id or something?