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LtiException at /launch/ - Not able to launch Lti external app in Chrome


We are trying to configure and launch an external LTI app in a bitnami-hosted instance of Canvas. After configuring the tool according to online doc and configuring the dynamic_settings.yml as noted online, we are still unable to get it to work correctly. The LTI tool is a Django application is a fork of this repository and it is currently hosted in Heroku. The form data received after header request is as follows:

error: Missing id_token

error_description: Must have an active user session


The error log output is:


Request Method: POST
Request URL: https://app/launch/

Django Version: 3.1.8
Python Version: 3.9.5
Installed Applications:
Installed Middleware:


Traceback (most recent call last):
File "/app/.heroku/python/lib/python3.9/site-packages/django/core/handlers/", line 47, in inner
response = get_response(request)
File "/app/.heroku/python/lib/python3.9/site-packages/django/core/handlers/", line 181, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/app/.heroku/python/lib/python3.9/site-packages/django/views/decorators/", line 40, in inner
return func(request, *args, **kwargs)
File "/app/game/game/", line 89, in launch
message_launch_data = message_launch.get_launch_data()
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 437, in get_launch_data
return self._get_jwt_body()
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 290, in _get_jwt_body
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 275, in validate
return self.validate_state()\
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 537, in validate_state
id_token_hash = self._get_id_token_hash()
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 310, in _get_id_token_hash
id_token = self._get_id_token()
File "/app/.heroku/python/lib/python3.9/site-packages/pylti1p3/", line 304, in _get_id_token
raise LtiException("Missing id_token")

Exception Type: LtiException at /launch/
Exception Value: Missing id_token


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