wait timeout for rendering needs to be configurable

[jleonard-r7]

Hi,

I have a situation where the following wait is not long enough (for a "default" google maps devcard). The render proceeds because devcard elements are present and the following sleep expires but the actual rendered bits are in an in-between state where the render is clearly not complete and the colors are kinda grayed out (seems that google maps must come in as a sort of gradient animation).

kamera/src/clj/kamera/core.clj

Line 222 in 085b2df

(Thread/sleep 500) ;; small timeout for any js rendering

What do you suggest for this situation?

[jleonard-r7]

(This obviously is an intermittent failure. Many times the render has in fact completed in that timeframe and thus matches the reference image).

[oliyh]

Hi,

Have you tried the :ready? predicate? From the README:
:ready? (fn [session] ... ) ;; predicate that should return true when screenshot can be taken

kamera/src/clj/kamera/core.clj

Lines 219 to 220 in 085b2df

	(when ready?
	(wait-for session ready?))

You can implement it to execute some javascript and try to determine if it's ready or not.

[jleonard-r7]

We have 50 devcards. The default devcard ready? is fine for 49 of them. As far as I know it isn’t possible to override ready? for just one of the devcards.

[oliyh]

Hello,

Yes, if you are using the kamera.devcards namespace you can provide this extra option as per the reader:

:on-targets (fn [targets] ... )} ;; function called to allow changing the targets before the test is run

This will let you set the ready? fn for your specific devcard. The alternative is, in your generic ready? fn to look for the presence of a Google maps div and wait for it to be ready if it finds one.