Timing problem when rendering specific dashboard

[amotl]

When trying to render https://weather.hiveeyes.org/grafana/d/of6c9qlmk/uba-ldi-dwd-studio-dev, it feels like grafanimate has some problem taking the snapshot at exactly the time after data loading has finished, see screenshot:

[amotl]

It looks like it works reasonably good on our machine (see attached logfile excerpt). While this dashboard seems to be rather heavy, grafanimate seems to be happily waiting for the synthesized all-data-received event (https://github.com/daq-tools/grafanimate/blob/c35b06cc4d7b9469d67083161c82c89b553cecf6/grafanimate/grafana-studio.js#L201-L244) before advancing to the next frame.

As the all-data-received event isn't offered by Grafana itself, I am aware there might be problems here, so I really would like to make this part as robust as possible.

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2019-02-05 02:15:16,809 [grafanimate.scenarios         ] INFO   : Saved frame to ./var/spool/of6c9qlmk/of6c9qlmk_2018-10-06T05-00-00.png. Size: 213758
2019-02-05 02:15:16,810 [grafanimate.animations        ] INFO   : Datetime step: 2018-10-06 06:00:00
2019-02-05 02:15:16,810 [grafanimate.grafana           ] INFO   : Timewarp to 2018-10-06 06:00:00 -> 2018-10-06 06:59:59
2019-02-05 02:15:16,913 [grafanimate.grafana           ] INFO   : Waiting for "all-data-received" event

2019-02-05 02:15:29,061 [grafanimate.scenarios         ] INFO   : Saved frame to ./var/spool/of6c9qlmk/of6c9qlmk_2018-10-06T06-00-00.png. Size: 214795
2019-02-05 02:15:29,062 [grafanimate.animations        ] INFO   : Datetime step: 2018-10-06 07:00:00
2019-02-05 02:15:29,062 [grafanimate.grafana           ] INFO   : Timewarp to 2018-10-06 07:00:00 -> 2018-10-06 07:59:59
2019-02-05 02:15:29,150 [grafanimate.grafana           ] INFO   : Waiting for "all-data-received" event

2019-02-05 02:15:41,284 [grafanimate.scenarios         ] INFO   : Saved frame to ./var/spool/of6c9qlmk/of6c9qlmk_2018-10-06T07-00-00.png. Size: 215439
2019-02-05 02:15:41,284 [grafanimate.animations        ] INFO   : Datetime step: 2018-10-06 08:00:00
2019-02-05 02:15:41,284 [grafanimate.grafana           ] INFO   : Timewarp to 2018-10-06 08:00:00 -> 2018-10-06 08:59:59
2019-02-05 02:15:41,366 [grafanimate.grafana           ] INFO   : Waiting for "all-data-received" event

2019-02-05 02:15:54,521 [grafanimate.scenarios         ] INFO   : Saved frame to ./var/spool/of6c9qlmk/of6c9qlmk_2018-10-06T08-00-00.png. Size: 216375
2019-02-05 02:15:54,521 [grafanimate.animations        ] INFO   : Datetime step: 2018-10-06 09:00:00
2019-02-05 02:15:54,521 [grafanimate.grafana           ] INFO   : Timewarp to 2018-10-06 09:00:00 -> 2018-10-06 09:59:59
2019-02-05 02:15:54,605 [grafanimate.grafana           ] INFO   : Waiting for "all-data-received" event