Microsoft Graph API token validation failure

Question

I would use Microsoft Graph API in my Angular Web application.

First I make connexion using msal library When I try log in with my profil I get this error

I have configured my app as the mentionned in the official git sample

MsalModule.forRoot({
  clientID: "Tenant ID",
  authority: "https://login.microsoftonline.com/common/",
  redirectUri: "http://localhost:4200/",
  validateAuthority : true,
  popUp: true
}),

Authetification is working and I get the token.

Then when I'm in home page I make a second request to Microsoft Graph API to get user information using that token.

getProfile() {
  let header= new Headers();
  let tokenid= sessionStorage.getItem('msal.idtoken'); 
  header.set('Authorization', 'Bearer ' + tokenid)
  let url ="https://graph.microsoft.com/v1.0/me/"
  return this.http.get(url,{headers:header});
}

}

I get an 401 Unauthorized error with a response :

{
  "error": {
    "code": "InvalidAuthenticationToken",
    "message": "Access token validation failure.",
    "innerError": {
      "request-id": "xxxxxx",
      "date": "2018-10-09T22:58:41"
    }
  }
}

I don't know why MG API is not accepting my token, Am I using wrong authority url ?

UPDATE: I have understood that actually I get id_token which is different from access token. How can I get Access token from MSAL library to make MS GRAPH API calls ?:

Answer 1

According to the same sample you can also attach an HttpInterceptor that will automatically attach the access token to each (external) HTTP call.

By reading through the documentation I found the following information.

consentScopes: Allows the client to express the desired scopes that should be consented. Scopes can be from multiple resources/endpoints. Passing scope here will only consent it and no access token will be acquired till the time client actually calls the API. This is optional if you are using MSAL for only login (Authentication).

That suggests that using the HttpInterceptor doesn't only attach the access token, but also retrieves it. The token that you're seeing is probably just a token for your application, but isn't a valid token for the Graph API.

Internally it uses getCachedTokenInternal(scopes: Array<string>, user: User) to get a new access token for specific scopes code found here. I'm not sure if you can use this method as well to get a new token for that resource. I would just use the interceptor.

You could try to copy the access token and see how it looks like on jwt.ms (a Microsoft provided JWT token viewer) or jwt.io.

Any tokens valid for Graph should have the Audience of https://graph.microsoft.com, so if you inspect the token (in jwt.ms) it should at least have this value.

"aud": "https://graph.microsoft.com",