How to get the response from Azure Data Lake Rest API using Azure API Management? - azure-data-lake

Question

I want to make a call to the Azure Data Lake Gen 1 using Data Lake rest API. I tried making the call through Javascript but because I ran into CORS, I decided to have a layer between JS and ADLS using Azure API Management. So basically a user would call the APIM and the APIM internally would call the ADLS Rest API and send me the response. Using the CURL command as reference,
curl -X POST https://login.microsoftonline.com/<TENANT-ID>/oauth2/token \
-F grant_type=client_credentials \
-F resource=https://management.core.windows.net/ \
-F client_id=<CLIENT-ID> \
-F client_secret=<AUTH-KEY>
I am trying to fetch the OAuth Token from ADLS using APIM. This is what I have so far,
The APIM Policies :
<policies>
<inbound>
<base />
<set-method>POST</set-method>
<set-header name="Content-Type" exists-action="override">
<value>"application/x-www-form-urlencoded"</value>
</set-header>
</inbound>
<backend>
<set-body>{
'grant_type':'client_credentials',
'resource':'https://management.core.windows.net/',
'client_id':'#################################',
'client_secret':'#######################'
}</set-body>
</backend>
<outbound>
</outbound>
<on-error>
<base />
</on-error>
</policies>
I can successfully make a call to the ADLS but how do I consume the response from APIM that is the OAuth token and route it to my caller in APIM?

Answer 1

Depending on how you configured your API you may also need to add rewrite-uri and/or set-backend-service into inbound to direct call to https://login.microsoftonline.com.
Otherwise try:
<policies>
<inbound>
<base />
<set-method>POST</set-method>
<set-header name="Content-Type" exists-action="override">
<value>"application/x-www-form-urlencoded"</value>
</set-header>
<set-body>{
'grant_type':'client_credentials',
'resource':'https://management.core.windows.net/',
'client_id':'#################################',
'client_secret':'#######################'
}</set-body>
</inbound>
<backend>
<forward-request/>
</backend>
<outbound>
<base />
</outbound>
<on-error>
<base />
</on-error>
</policies>