AWS Cognito：无法获取凭据

Question

i can't get the Credentials for my CognitoIdentity. When the User is successfully authenticated, he needs to get a Identity to access other AWS Services. In my case thats AWS IoT. But for somehow, i can't get any credentials.

This is the Error Message:

Error retrieving credentials: NotAuthorizedException: Access to Identity 'eu-central-1:XXXXXXXXXX' is forbidden.

My Code is almost exactly like the Tutorial on Github:

 var cognitoUser = new AWSCognito.CognitoUser(userData);
  cognitoUser.authenticateUser(authenticationDetails, {
    onSuccess: function (result) {
      console.log("Logged in");
      console.log('access token + ' + result.getAccessToken().getJwtToken());
      //    window.location.href = "index.html";
      AWS.config.region = AWSConfiguration.region;

      AWS.config.credentials = new AWS.CognitoIdentityCredentials({
        IdentityPoolId: AWSConfiguration.IdPoolId,
        Logins : {
          'cognito-idp.eu-central-1.amazonaws.com/eu-central-1_XXXX' : result.getIdToken().getJwtToken()
        }
      });
      var cognitoIdentity = new AWS.CognitoIdentity();
      AWS.config.credentials.get(function(err, data) {
        if (!err) {
          console.log('retrieved identity: ' + AWS.config.credentials.identityId);
          var params = {
            IdentityId: AWS.config.credentials.identityId
          };
          cognitoIdentity.getCredentialsForIdentity(params, function(err, data) {
            if (!err) {
              thingShadows.updateWebSocketCredentials(data.credentials.AccessKeyId,
                                                 data.credentials.SecretKey,
                                                 data.credentials.SessionToken);
            }
            else {
              console.log('error retrieving credentials: ' + err);
            }
          });
        }
        else {
          console.log('error retrieving identity:' + err);
        }
      });
    }
  });  

Please note that i skipped not related code. authenticated users have full access to all AWS services i'm using.

Answer 1

I don't think you need to call cognitoIdentity.getCredentialsForIdentity() . Your IAM keys should be put into the AWS.config.credentials object when you call AWS.config.credentials.get() . You can access them directly in the callback you provide when you call it.

In other words, when you're logging out the retrieved identity: to the console, the credentials object should already have your secret key, access key id, and session token in it.

All of this (give or take a curly brace):

 var params = {
    IdentityId: AWS.config.credentials.identityId
  };
  cognitoIdentity.getCredentialsForIdentity(params, function(err, data) {
    if (!err) {
      thingShadows.updateWebSocketCredentials(data.credentials.AccessKeyId,
                                         data.credentials.SecretKey,
                                         data.credentials.SessionToken);
    }
    else {
      console.log('error retrieving credentials: ' + err);
    }
  });

Can probably be replaced with something like this:

thingShadows.updateWebSocketCredentials(AWS.config.credentials.accessKeyId,
                                        AWS.config.credentials.secretKey,
                                        AWS.config.credentials.sessionToken);

If you pass in a Logins map with the user pool id and access token in it, the getCredentialsForIdentity() call might succeed; I didn't test it. I haven't yet run into a use case where I needed to use this particular API, and I suspect you don't need it either.

Source: I work on a 100% javascript application that uses both authenticated and unauthenticated Cognito identities. We don't call getCredentialsForIdentity() anywhere, and trying to insert it produced the same error you're getting.