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Anonymous
Not applicable

Log Analytics Error 400 Bad Request

I'm using the export to Power BI (M query) functionality thorugh azure log analytics.

 

The dashboard was working since a week ago, but now some log analytics query are giving me an error, but some not:

 

DataSource.Error: Web.Contents failed to get contents from 'https://api.loganalytics.io/v1/workspaces/xxxxxxxxxxxxxxxxxxx/query?query=Event%0D%0A%7C%20where%20EventLog%20%3D%3D%20%22System%22%20and%20Source%20%3D%3D%20%22Service%20Control%20Manager%22%0D%0A&x-ms-app=OmsAnalyticsPBI&timespan=P7D&prefer=ai.response-thinning%3Dtrue' (400): Bad Request
Details:
    DataSourceKind=Web
    DataSourcePath=https://api.loganalytics.io/v1/workspaces/xxxxxxxxxxxxx/query
    Url=https://api.loganalytics.io/v1/workspaces/xxxxxxxxxxxxxxxxxx/query?query=Event%0D%0A%7C%20where%20EventLog%20%3D%3D%20%22System%22%20and%20Source%20%3D%3D%20%22Service%20Control%20Manager%22%0D%0A&x-ms-app=OmsAnalyticsPBI&timespan=P7D&prefer=ai.response-thinning%3Dtrue

 

 

1 ACCEPTED SOLUTION
v-yingjl
Community Support
Community Support

Hi @Anonymous ,

There is a similar blog providing details about how to connect to API in Power BI, you can following the instructions in this blog to connect to your data source.

If you still get error, you can use Fiddler to track the process following the guide in this video.

 

In addition, you can refer this simliar issue and the blog which introduces Web.Contents():

  1. 400: Bad Request in Power Query RRS feed 
  2. Web.Contents(), M Functions And Dataset Refresh Errors In Power BI 

 

Best Regards,
Community Support Team _ Yingjie Li
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

View solution in original post

4 REPLIES 4
v-yingjl
Community Support
Community Support

Hi @Anonymous ,

There is a similar blog providing details about how to connect to API in Power BI, you can following the instructions in this blog to connect to your data source.

If you still get error, you can use Fiddler to track the process following the guide in this video.

 

In addition, you can refer this simliar issue and the blog which introduces Web.Contents():

  1. 400: Bad Request in Power Query RRS feed 
  2. Web.Contents(), M Functions And Dataset Refresh Errors In Power BI 

 

Best Regards,
Community Support Team _ Yingjie Li
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

Anonymous
Not applicable

Hi @v-yingjl ,

I installed Fiddler and the actual error is:

{
  "error": {
    "message": "Response size too large",
    "code": "ResponseSizeError",
    "correlationId": "552a4fc6-dcd1-4d21-9fd0-d6523dd4af77",
    "innererror": {
      "code": "ResponseSizeError",
      "message": "Maximum response size of 67108864 bytes exceeded. Actual response Size is 70694713 bytes."
    }
  }
}

Is it normal? 

How can I fix it?

Anonymous
Not applicable

I have opened a new ticket: https://community.powerbi.com/t5/Power-Query/Log-Analytics-Response-size-too-large/m-p/1721870#M5223...

 

You response is correct to find the real error so I'll accept it

khregs
Advocate III
Advocate III

Same issue on my end. Our Log Analytics reports stopped working on Monday with the same error.

Change happened sometime between 12:00pm and 3:00pm EST on Monday March 8, 2021.

Thanks,

Craig

khregs_0-1615495170402.png

 

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