(415) Unsupported media type error when using Power Query for POST request

[Anonymous]

I am trying to use Power Query in Power BI for a POST request, and I am getting this (415) unsupported media type error. The content has been tested in Postman (an API tester). Any help is appreciated.

let
    content = "{
    ""spec"": {
        ""ids"": [""0001""],
        ""interval"":""HOUR"",
        ""expressions"": [
            ""CompoundChilledWaterConsumptionForecast""
        ],
        ""start"": ""2020-01-01T00:00:00.000"",
        ""end"": ""2020-01-02T09:00:00.000"",
        ""include"": ""start, end, interval, count, dates, data, timeZone, unit""
        }
    }",
    Source = Json.Document(Web.Contents("https://engie-osep.c3iot.com/api/1/engie-osep/prod/Facility?action=evalMetrics", [Headers=[Authorization="Basic xxxxxx"], Content=Text.ToBinary(content)]))
in
    Source

[Greg_Deckler]

Assuming you meant 415, unsupported media type and not 414, URI too long. 

Definitely does not like your headers. Maybe play with some of the optional parameters for ToBinary?

https://docs.microsoft.com/en-us/powerquery-m/text-tobinary

@ImkeF @edhans you guys do much with stuff like this? Is that endpoint really expecting that in binary?

[Anonymous]

sorry that was a typo, fixed it.

that Text.ToBinary() is something I copied from other threads. If I remove it and just pass the JSON body to Content, it gives another error.

[ImkeF]

Yes @Anonymous ,

my bad - your original syntax looks alright. Content has to be a binary value.

Just re-check the error message and if nothing different comes up that can give a hint you should use Fiddler to compare the commands that both tools send.

[edhans]

Sorry, I don't have much experience about this particular topic. 😐

[ImkeF]

Hi

that's just a bracket at the wrong position. Try this:

let
    content = "{
    ""spec"": {
        ""ids"": [""0001""],
        ""interval"":""HOUR"",
        ""expressions"": [
            ""CompoundChilledWaterConsumptionForecast""
        ],
        ""start"": ""2020-01-01T00:00:00.000"",
        ""end"": ""2020-01-02T09:00:00.000"",
        ""include"": ""start, end, interval, count, dates, data, timeZone, unit""
        }
    }",
    Source = Json.Document(Web.Contents("https://engie-osep.c3iot.com/api/1/engie-osep/prod/Facility?action=evalMetrics", [Headers=[Authorization="Basic xxxxxx", Content=Text.ToBinary(content)]]))
in
    Source

[Anonymous]

Hi Imke,

thanks a lot for the answer.

But after changing to your way, I got a different error:

Expression.Error: We cannot convert a value of type Binary to type Text.
Details:
    Value=[Binary]
    Type=[Type]

which I think makes sense because, in your solution content is included in the header section. But content should be in the body of a POST request. Any thoughts?