Power BI Reports Connection String change on Power BI Report Server using Rest API

Hi,

As Jon-Heide mention, at the moment PowerBI is not supporting it.

For this issue, I done some workaround as below.

• In ReportServer database, "DataModelDataSource" table has connection string details of each datasource in PowerBI Report (with ItemId refeence) but this is in varbinary/encrypted format.
• For Example if you are moving the report from Dev. environment to Prod. Environment
• Create dummy report with Prod env as datasource details and upload that report in development environment, then you can get connection string (in varbinary) from DataModelDataSource table, keep this string as your new datasource connection string for prod environment.
• After publishing the reports in prod environment, for this particular itemid and datasource id, repalce the new connection string.
• You can get the Item ID and Datasource ID "Get-RsRestItemDataSource" method.
• You need to maintain the Prod. env encrypted connection string (combination of server name and database name) and need to pass to PowerShell script while publishing the report.
• Using belowquery, you can update the new connection string (Prod. env) for each report. 

$Query = "Declare @varCharConnectionString varchar(max); 
		SELECT @varCharConnectionString = '" + $EncryptedConnectionString + "'; 
		Update DataModelDataSource set ConnectionString = convert(varbinary(max),@varCharConnectionString,1) 
		Where ItemId = '" + $PowerBIReportItem.Id + "' and DataSourceID ='" + $PowerBIReportDataSource.Id + "'"
Invoke-Sqlcmd -Query $Query -ServerInstance $ReportServerName -Database $ReportServerDatabaseName -Username $ReportServerDatabaseUserName -Password $ReportServerDatabasePassword

I hope this will help you..

Thanks,

Navaneethakrishnan Thangaraj