Power BI API with Dynamics 365

Hi 

You can try something like this

let
    pStartDate = Date.AddDays(DateTime.LocalNow(),-10), // 10 days prior of today
    pEndDate = DateTime.LocalNow(), // today
    urlString = "https://xxxxxxxxxxxxx and postingDate ge '" & Text.From(pStartDate) & "' and postingDate lt '" & Text.From(pEndDate) & "'",
    Source = Json.Document(Web.Contents(urlString))
in
    Source

The pStartDate and pEndDate may not be in the correct format that this API requires, you can use Date.ToText or DateTime.ToText function to change its format. 

If you want to set scheduled refresh, above query will give you an dynamic data source cannot be refreshed error. In that case, you need to set RelativePath and Query options with Web.Contents(). Please refer to

Chris Webb's BI Blog: Using The RelativePath And Query Options With Web.Contents() In Power Query And Power BI M Code

Web.Contents with complex Query parameter names - Microsoft Power BI Community

Best Regards,
Community Support Team _ Jing
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