topic Re: CORS Error - Generate Token in ArcGIS JavaScript Maps SDK Questions

CORS Error - Generate Token

AndrewMurdoch1 — Tue, 03 Aug 2021 16:00:04 GMT

Good Day

A function which retrieves the token for a client, and uses it to authenticate to the hosted feature layer, started failing out of the blue, throwing CORS errors from Angular.

The specific error we're getting is:

Access to fetch at 'https://<client>.geopedia.ca/portal/sharing/rest/generateToken' from origin 'http://localhost:4200' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. If an opaque response serves your needs, set the request's mode to 'no-cors' to fetch the resource with CORS disabled.

When we try to access the resource using Insomnia or Postman, we can get a token, and the code we used to fetch the token was working fine a couple of weeks ago, this is the function:

I generated the tokenParams object using: https://<client>.geopedia.ca/portal/sharing/rest/generateToken which will also return a token. I haven't changed anything in this code in weeks, so I have to assume it's either something on the clients side or ESRI's.

Has anyone run into similar issues?

Thanks

Re: CORS Error - Generate Token

AndyGup — Tue, 03 Aug 2021 16:16:12 GMT

I took a quick look and it looks like geopedia.ca is a self-hosted Portal? If so, it's possible something changed on their server-side CORS configuration. Otherwise, you'll need to do some testing to figure out which header within the app is triggering the error, or maybe you are missing a header.

Re: CORS Error - Generate Token

AndrewMurdoch1 — Tue, 03 Aug 2021 16:32:11 GMT

Good Day

We can have them look, it's self-hosted, and they've been troubleshooting a problem with ESRI, so they may have changed the settings to something invalid. It's odd the request works from Post Man / Insomnia, but not from Angular.

My co-worker also ran the token query from C# and was able to retrieve the token. We'll reach out to the client in question.

Thanks

Re: CORS Error - Generate Token

AndyGup — Tue, 03 Aug 2021 17:08:05 GMT

Postman gives precise control over headers, in comparison you may not be aware of all the headers that are being generated by the JavaScript-based request() method. That's why we recommend comparing headers between requests that are successful and requests that aren't.

Re: CORS Error - Generate Token

AndrewMurdoch1 — Wed, 04 Aug 2021 16:59:33 GMT

Good Day

The problem is on the client's server, but they don't know how to resolve it. We've bypassed the issue for now, by using a token and passing it to the request API.

Thanks for your help 🙂