Google Compute Engine: Can't authorize request to Task Queue API - google-app-engine

Question

everyone.
I'm having trouble trying to authorize my Compute Engine instance to lease tasks on a Task Queue queue.
I've included de necessary scopes (I think), in the instance creation config:
"metadata": {
"kind": "compute#metadata",
"items": [
{
"key": "startup-script-url",
"value": "[MY-STARTUP-SCRIPT]"
},
{
"key": "service_account_scopes",
"value": "https://www.googleapis.com/auth/cloud-platform"
}
]
},
"serviceAccounts": [
{
"email": "[MY-SERVICE-ACCOUNT]",
"scopes": [
"https://www.googleapis.com/auth/devstorage.read_only",
"https://www.googleapis.com/auth/logging.write",
"https://www.googleapis.com/auth/taskqueue",
"https://www.googleapis.com/auth/cloud-platform",
"https://www.googleapis.com/auth/compute"
]
}
Also in my queue.yaml, I have added the same service account to the acl directive with the "user_email" attribute:
queue:
- name: [MY-QUEUELIST]
mode: pull
retry_parameters:
task_retry_limit: 5
acl:
- user_email: [MY-COMPUTE-ENGINE-SERVICE-ACCOUNT]
Finally, the script that I run on my instance uses the GoogleCredentials.get_application_default() function to obtain the credentials. This credentials are passed as argument to the build() method (as stated here: https://cloud.google.com/compute/docs/authentication):
The end result is that when I try to list the task of the given taskqueue I get this error:
googleapiclient.errors.HttpError: https://www.googleapis.com/tasks/v1/lists/documentation-compiler-queue/tasks?alt=json
returned "Insufficient Permission">
What am I missing?!
Thanks in advance.

Answer 1

I got my own mistake!
Just ignore this cuestion. I was using:
from googleapiclient.discovery import build
taskqueue_service = build('task', 'v1beta2', credentials=credentials)
instead of:
from googleapiclient.discovery import build
taskqueue_service = build('taskqueue', 'v1beta2', credentials=credentials)
Note the [API name] string in the build method