I’ve got a frustrating recurring problem with image loading on Mapillary JS. I run a small non-profit using Mapillary to identify road hazards. We have integrated Mapillary JS with our own Vue app (https://map.safe7y.com/) to quickly review images of the road and compare them to the road safety devices we inventory.
After about 20 minutes of use - maybe 2,000 or so Mapillary images viewed, we find that all mapillary images cease loading and we get the following error messages:
Access to XMLHttpRequest at 'https://graph.mapillary.com/images?image_ids=568070274306488&fields=id,comp…erge_cc,mesh,quality_score,sfm_cluster,thumb_1024_url,thumb_2048_url,width' from origin 'https://map.safe7y.com' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: It does not have HTTP ok status. mapillary.module.js:85439 Failed to cache image (568070274306488). MapillaryError: Failed to fetch data at chunk-vendors.843f91ed.js:38 (anonymous) @ mapillary.module.js:85439 graph.mapillary.com/…mb_2048_url,width:1 Failed to load resource: net::ERR_FAILED mapillary.module.js:82228 Uncaught (in promise) MapillaryError: Failed to fetch data at chunk-vendors.843f91ed.js:38
This is what it looks like from within our app.
I am taking over this code from the original developer, and I am Vue novice but it seems to be a verily vanilla implementation of the Mapillary JS viewer v4. All our code for this project is open source and I believe the majority of the API interface occurs here:
What is frustrating about this particular error is that it seems to be time based. 30 minutes later the same, user, without refreshing, can load the images that threw errors before. Refreshing the page does not fix the issue, nor does clearing cookies, switching browsers, switching IP addresses or switching computers.
Once the user is able to review images the following error are thrown, which may be related:
Unchecked runtime.lastError: The message port closed before a response was received. mapillary.module.js:48502 Uncaught (in promise) CancelMapillaryError: Request aborted by a subsequent request to id 223465049110163. at QO._abortRequest (mapillary.module.js:86675) at QO.moveTo$ (mapillary.module.js:86588) at rR.moveTo (mapillary.module.js:87714) at Imagery.vue:158 at u (runtime.js:63) at Generator._invoke (runtime.js:293) at Generator.next (runtime.js:118) at n (asyncToGenerator.js:3) at s (asyncToGenerator.js:25) at asyncToGenerator.js:32
My guess is that Mapillary is imposing a request limit, but I can’t find any documentation on this.