Channel Advisor API Connection with auth key creation

I am trying to use everybody's code snippets to connect to Channel Advisor's API. This part works:

() =>
let
    url = "https://api.channeladvisor.com/oauth2/token",
    headers = [#"Authorization"="Basic xxxxxxx="],
    postBody = [
        grant_type = "refresh_token", 
        refresh_token = "xxxxxxxx"
        ],
    response = Json.Document(Web.Contents(url,
        [
            Headers = headers,
            Content = Text.ToBinary(Uri.BuildQueryString(postBody))
        ])),
    access_token = response[access_token]
in
    access_token

What doesn't work is this part:

let
    Source = Json.Document(Web.Contents("https://api.channeladvisor.com/oauth2/token",
                       [Headers=[#"Authorization"="bearer " & GetAccessToken(), 
                                 #"accept" = "text/plain", 
                                 #"Content-Type"="application/json"], 
                                  
                        ManualStatusHandling = {404, 400}]))

in
    Source

I have tried it with "Bearer" vs. "bearer" and a few other things, but either I get a 400 error OR the Power Query output simply gives me a small table that says "error | invalid client".

What am I doing wrong?

Were you able to accomplish the first part in Power Query (ie getting the refresh key) ?

Hi TrysHisBest 

Do you send a Post request to get the key? If so, you need to put request body in Content parameter of Web.Contents function. 

Here is an example for Post request. Create a blank query, open its Advanced Editor, remove the code there and paste below code to it.

let
    url = "https://xxxxxxxxxxxxxxxxxxxxxxxx",
    headers = [#"Content-Type" = "application/x-www-form-urlencoded", #"Accept" = "*/*"],
    postBody = [
        grant_type = "xxxxxxxxxx", 
        username = "xxxxxxxxxxxxxxxx",
        password = "xxxxxxxxxxx"
        ],
    response = Json.Document(Web.Contents(url,
        [
            Headers = headers,
            Content = Text.ToBinary(Uri.BuildQueryString(postBody))
        ]))
in
    response

Once you get the key, you can then use it in another Web.Contents statement to get data for your report. 

Best Regards,
Community Support Team _ Jing
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