Forum Discussion
Please Help: Trying to encode/decode Access Token (Rest API)
Hi Folks,
I'm new to Power BI and was hoping I could ask someone over here for some advice. I'm working with the Rest API. And well, I've got most of what I need working within the Power Query when I hardcode an access token (retrieved from PostMan). However, when I try to replicate the PostMan code and retrieve the key within PowerBI it fails.
If the value isn't hardcoded it returns an error about converting a value of type function to type logical. I'm a bit at a lost. Maybe I need to parse/decode the data being passed back? PostMan does this automatically. Any guidance or point of direction would be much appreciated!
The snippet of code in question is the following:
GetPages = () =>
let
Source =
Json.Document(
Web.Contents(
"https://REMOVED/api/Token",
[
Headers =
[
#"Content-Type"="application/x-www-form-urlencoded" //,
],
Content = Text.ToBinary("Username=REMOVED&Password=REMOVED&grant_type=password&Integrated=N&database=REMOVED&Client_Id=REMOVED=&client_secret=REMOVED",BinaryEncoding.Base64,Binary.Compress) ]
)
),
//This fails
apikey = Source[access_token],
//This works (copied and pasted from PostMan
apikey = "INSERT_POSTMAN_CODE",
--header 'Content-Type: application/x-www-form-urlencoded' \
--data-urlencode 'Username=REMOVED' \
--data-urlencode 'Password=REMOVED' \
--data-urlencode 'grant_type=password' \
--data-urlencode 'Integrated=N' \
--data-urlencode 'database=REMOVED' \
--data-urlencode 'Client_Id=REMOVED' \
--data-urlencode 'client_secret=REMOVED'
For those curious this eventually was determined to be a server bug. However, I did clean up the final code. Attached is the working code for anyone that wants it...
(environment as text) as text => let sand_UserID = [REMOVED], sand_Database = [REMOVED], sand_Password = Uri.EscapeDataString([REMOVED]), sand_Client_Secret = Uri.EscapeDataString([REMOVED]), //EscapeDataString is required for any phrase that includes special characters, although probably doesn't hurt to have on all of them. prod_UserID = [REMOVED], prod_Database = [REMOVED], prod_Password = Uri.EscapeDataString([REMOVED]), prod_Client_Secret = Uri.EscapeDataString([REMOVED]), Client_ID = Uri.EscapeDataString([REMOVED]), UserID = if environment = "sand" then sand_UserID else prod_UserID, Database = if environment = "sand" then sand_Database else prod_Database, Password = if environment = "sand" then sand_Password else prod_Password, Client_Secret = if environment = "sand" then sand_Client_Secret else prod_Client_Secret, token_url = "https://[REMOVED]/api/", body="Username="&UserID&"&Password="&Password&"&grant_type=password&Integrated=N&database="&Database&"&Client_Id=" & Client_ID & "&Client_Secret=" & Client_Secret, params = [ Content = Text.ToBinary(body), RelativePath = "Token", Headers = [#"Content-Type"="application/x-www-form-urlencoded"] ], WebSource = Json.Document(Web.Contents(token_url,params)), apikey = WebSource[access_token] in apikey
12 Replies
The bug is not in access_token, it is in your source variable. When you reference Source it is evaluated, as such when you hard code the access token in Source is never evaluated. The actual bug is in Text.ToBinary where you pass the 3rd parameter as a function (without invoking it), but what it expects is a byte order either ByteOrder.BigEndian or ByteOrder.LittleEndian.
Thank you for the prompt follow-up!
I'm a bit rusty to programming, and not at all familar with Power Query / M. However, I tried your recommendation.
When I invoked:
Content=Text.ToBinary(body,BinaryEncoding.Base64, ByteOrder.BigEndian)
It responded:
Expression.Error: We cannot convert the value 1 to type Logical.
Details:
Value=1
Type=[Type]Likewise, LittleEndian, responded with "value 0" and, as you noted, Binary.Compress, responds with "Function" in place of the value in the error message. I think we are on the right path, as this change definitely updated the error. However, going this path, I guess I'm a bit thrown by why the error happens so far upstream (although it sounds like the language just ignores "Source" if I don't reference the value after storing it, that's a bit wierd?!?). The next line is to set the session's API to the token returned. If I try just random garbage, the system realizes the credentials have failed and will not pull the API call for the data request. However, if I set the string to the value obtained from PostMan, it works just fine and pulls the data. I guess I'm just surprised, it isn't responding saying bogus credidentials and/or with that 400 error message.
Definitely heading the right direction... any other thoughts or advice? Seriously... been pulling my hair out looking at this one all day... Thank you so much in advance.
For those curious this eventually was determined to be a server bug. However, I did clean up the final code. Attached is the working code for anyone that wants it...
(environment as text) as text => let sand_UserID = [REMOVED], sand_Database = [REMOVED], sand_Password = Uri.EscapeDataString([REMOVED]), sand_Client_Secret = Uri.EscapeDataString([REMOVED]), //EscapeDataString is required for any phrase that includes special characters, although probably doesn't hurt to have on all of them. prod_UserID = [REMOVED], prod_Database = [REMOVED], prod_Password = Uri.EscapeDataString([REMOVED]), prod_Client_Secret = Uri.EscapeDataString([REMOVED]), Client_ID = Uri.EscapeDataString([REMOVED]), UserID = if environment = "sand" then sand_UserID else prod_UserID, Database = if environment = "sand" then sand_Database else prod_Database, Password = if environment = "sand" then sand_Password else prod_Password, Client_Secret = if environment = "sand" then sand_Client_Secret else prod_Client_Secret, token_url = "https://[REMOVED]/api/", body="Username="&UserID&"&Password="&Password&"&grant_type=password&Integrated=N&database="&Database&"&Client_Id=" & Client_ID & "&Client_Secret=" & Client_Secret, params = [ Content = Text.ToBinary(body), RelativePath = "Token", Headers = [#"Content-Type"="application/x-www-form-urlencoded"] ], WebSource = Json.Document(Web.Contents(token_url,params)), apikey = WebSource[access_token] in apikey
