I’ve seen this issue pop up with the Google Analytics GA4 connector, especially when using Dataflow Gen2 and Fabric pipelines. The “unexpected character in the JSON input” (with DataFormat.Error and Value = \31) is something I’ve hit before too, and it’s def a pain.

From what you described, it looks like the root problem is with the way credentials get handled in the connector, and it’s actually a known bug (as you found). Sometimes the pipeline tries to pass parameters in a way the connector doesn’t expect, so it fails on the JSON parse step.

The workaround that’s usually shared (deleting and recreating the connection, using “Skip Test Connection”) hasn’t really worked for everyone. The DMTS_InvalidDatasourceTypeForSkipTestConnectionError is a sign that the connector isn’t letting you skip the test for that specific datasource type – it’s a bit annoying because not all connectors support the skip test option, even though the UI allows you to try.

Right now, unfortunately, there isn’t a perfect fix for this. What sometimes helps:

• Double check if all the parameters being passed at runtime are exactly in the expected format (sometimes a sneaky empty value or special char causes the parse error).
• If possible, try to create the connection manually (not through CI/CD) and then reference that connection in your pipeline – it’s not ideal, but can sometimes get you unstuck.
• Keep an eye on the official updates for the connector. Microsoft is aware of this and working on a patch, but it’s not out yet.

If this is blocking a production workflow, you might want to log a support ticket directly with Microsoft just to get more visibility on your case.

Hope that helps at least a bit. Sorry I can’t give a magic fix here – just wanted to let you know you’re not the only one seeing this.

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