Dataset Refresh API doesn't work from Power Query

[trt18-sistemas]

Hi there,

I'm trying to implement a Power Query Script that refresh a dataset by using "Dataset - Refresh Dataset in Group" REST API (https://learn.microsoft.com/en-us/rest/api/power-bi/datasets/refresh-dataset-in-group).

I can trigger the dataset refresh by using Postman or direct using the "Try it" API page (https://learn.microsoft.com/en-us/rest/api/power-bi/datasets/refresh-dataset-in-group#code-try-0), but when I call for this API by using Power Query at Power BI Desktop, it just doesn't work.
Bellow is Power Query Script, where GetAccessToken is a separated Query that calls for Microsft API in order to retrieve a valid Token. It's working fine. I can say that because when I use the token return by GetAccessToken query and use it at Postman, it works.

let
    auto_token = "Bearer " & GetAccessToken,
    url_datasetlist = "https://api.powerbi.com/v1.0/myorg/groups/workspace_id00000/datasets/dataset_id00000/refreshes",
    content_type = "application/x-www-form-urlencoded",
    body="NotificationOption=MailOnCompletion",
    Source = Json.Document(Web.Contents(url_datasetlist, [Headers=[Authorization=auto_token, #"Content-Type"=content_type, Content=body]]))
in 
    Source

Source content is a record as you can see below:

Could any body help me find the problem? Any tip of what I'm doing wrong?

[v-stephen-msft]

Hi @trt18-sistemas ,

It seems that the issue is with the content_type parameter in the header. The content_type parameter should be set to "application/json" instead of "application/x-www-form-urlencoded". Try changing the content_type parameter to "application/json" and see if that resolves the issue.

Try the modified code:

let
    auto_token = "Bearer " & GetAccessToken,
    url_datasetlist = "https://api.powerbi.com/v1.0/myorg/groups/workspace_id00000/datasets/dataset_id00000/refreshes",
    content_type = "application/json",
    body = "{""notifyOption"": ""MailOnCompletion""}",
    Source = Json.Document(Web.Contents(url_datasetlist, [Headers=[Authorization=auto_token, #"Content-Type"=content_type], Content=Text.ToBinary(body)]))
in 
    Source

Best Regards,

Stephen Tao

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[trt18-sistemas]

Hi @v-stephen-msft ,

Thanks for your reply. I forget to mention that I've tried using Json and it returned a error. I've pasted your code on Power BI and the same error pop up again (message below). In this case, seems that the problem is how message is formated, but I can't see any thing wrong on the content.

Just in case, here is the print screen from my M code: