Power Platform Community Forum Thread Details

@jkottama201

There is limit of 16,384 characters for the URL length in Power Automate, such as for the value of HTTP Action Block under "URI"

Character limits (docs.microsoft.com)

CHARACTER LIMITS
Name	Notes
Expression evaluation limit	131,072 characters	The `@concat()`, `@base64()`, `@string()` expressions can't be longer than this limit.
Request URL character limit	16,384 characters

I did try it and I can reproduce it, it is expected behavior:

Note that there may be another issue - if you get another kind of error or a retry, the server may not be able to handle it. However, it sounds like in your case, that is not the issue.

Only idea I have is to Create a custom connector from scratch (however, this might not be a good idea - I suspect the limit of URL length may actually be even less, I did not try it but if I were to take a gues, possibly around 2,048 characters for the Custom Connector - so I would guess it is even less).

I am not sure of a workaround. The maxUrlLength value cannot be changed as it is a limit on Power Automate's side. The limit is in fact quite high in my opinion.

Is there any way to use an alternative such as a POST version of the API and then send this information somewhere else other than in the query string of the URL? If so, you may want to check on that as well for possible workaround here.

I also just noticed something else:

The error you stated is actually "The length of the URL for this request exceeds the configured maxUrlLength value". This may not be an error in Power Automate.

This is usually an error that shows up on server side , usually in ASP.NET type servers. and it is not actually the same as the error I reproduced above.

Note that the error might be on the ArcGIS side only.

Ask your admin to raise the applicable limit.

I believe in ArcGIS the limit is 2,000 characters.

Ask your admin to go in web.config change the maxQueryStringLength and modify the value to be higher.

You can ask your admin to refer to ArcGIS example like this here: https://support.esri.com/en/technical-article/000015245

In my opinion this issue appears to be related to your specific server infrastructure and not with Power Automate.