Office API getAccessTokenAsync result yields InvalidAuthenticationToken response from Graph - microsoft-graph-api

Question

i have been trying to tackle this issues for a while now, i am workin on an Office-js addin for Outlook and is trying to access Microsoft Graph data through my addin.
But i have been unable to authenticate the token i recieve from getAccessTokenAsync.
If i attempt to use the authenticator from Office-JS-Helpers i can get access, but i would prefer to use the built in function of the addin for it.
the code i am trying to use is this:
Office.initialize = () => {
var options = { forceAddAccount: true, forceConsent: true } as Office.AuthOptions;
Office.context.auth.getAccessTokenAsync(options, getAccessTokenAsyncCallback);
}
function getAccessTokenAsyncCallback(accessTokenResponse) {
console.log(accessTokenResponse.value)
client = MicrosoftGraph.Client.init({
authProvider: (done) => {
done(null, accessTokenResponse.value);
},
debugLogging: false
})
client.api("/me")
.get((err, res, rawResponse) => {
console.log(err)
console.log("rawResponse")
console.log(rawResponse)
})
}
and my WebApplicationInfo in my manifest is:
<WebApplicationInfo>
<Id>{AppUID}</Id>
<Resource>api://localhost:3000/{AppUID}</Resource>
<Scopes>
<Scope>profile</Scope>
<Scope>user.read</Scope>
</Scopes>
</WebApplicationInfo>
</VersionOverrides>
and the rights has been set up in my app on the Application Registration Portal.
as far as i can see when validating/decoding the JSON Web Token i recieve from getAccessTokenAsync, it should be valid.
but whenever i try to connect using this token i get this response:
{
"statusCode": 401,
"code": "InvalidAuthenticationToken",
"message": "Access token validation failure.",
"requestId": "4a0ce952-0e90-XXXXXXXXX-db20c6cca94e",
"date": "2018-08-30T05:37:43.000Z",
"body": {
"code": "InvalidAuthenticationToken",
"message": "Access token validation failure.",
"innerError": {
"request-id": "4a0ce952-0e90-XXXXXXXXX-db20c6cca94e",
"date": "2018-08-30T07:37:43"
}
}
}
i simply can't figure out what the issue is here, am i wrong in that the token returned from getAccessTokenAsync is the one i need for this?
oh yes and i am running up against an Office365 environment with Outlook 2016 version 1807 build 10325.20118 click to run

Answer 1

The token that is returned by getAccessTokenAsync, called the bootstrap token, does NOT give your add-in access to MS Graph directly. Instead it gives the Office host application, Outlook in this case, access to your add-in's web application. Your add-in's web application then uses that token to get an access token to Microsoft Graph. It does this by using the "on behalf of" OAuth flow. Please see the extensive documentation at this node: SSO in Office Add-ins and, for Outlook-specific guidance, also see Authenicate a user in an Outlook Add-in with an SSO token.