Authorization failing with 401,while trying to access azure rest apis

Question

I'm trying to call the inbuilt azure API by bearer token generation. The bearer token is generated using "https://login.microsoftonline.com/{tenantID}/oauth2/token,"; and using this token, I'm trying to access the get device API from IoT Hub. The headers i am providing for the REST API call are content-type and Authorization(with the bearer token). But it is returning an error message as below:

Message;:;ErrorCode:IotHubUnauthorized;3cc43d2f-def7-4a3e-a2ue-eb367467ab90 is not valid;

Can anyone please help me in solving this?

Hi Rakesh, did my answer help you at all? If not, let me know if I need to clarify it more. — Matthijs van der Veer

Matthijs van der Veer Matthijs van der Veer · Accepted Answer · 2020-07-17T08:14:23

To connect to your IoT Hub's Service API, you need a shared access token, not an oauth2 token. You can generate the token you need to set in your header through the az cli

az iot hub generate-sas-token -n {iothub_name}

If you like a more visual approach, you can use the Device Explorer. You can simply enter your IoT Hub connection string with service connect or iothubowner right and generate the token.

You can then use the service endpoints of your IoT Hub, here's an example curl request:

curl --request GET \
https://<hub-name>.azure-devices.net/devices?api-version=2018-06-30 \
--header "Authorization: SharedAccessSignature sr=<hub-name>.azure-devices.net&sig=KSobATNRdkFtd999999990v7NYU4hitkTA3ts%3D&se=1626508840&skn=iothubowner"

Authorization failing with 401,while trying to access azure rest apis

1 Answers