I'm using the Zappa framework https://github.com/Miserlou/Zappa with Python and Flask on AWS Lambda. When it raises an exception it appears in the CloudWatch log but is illegible to me. I do get a normal Flask stack trace returned from a HTTP GET in debug builds however.
My question is how do I get a reasonable (Flask) stack trace in logs / from production code? When exceptions are raised in production all I have is log messages.
Nice stack trace from HTTP GET:
Traceback (most recent call last):
File "/var/task/handler.py", line 96, in handler
response = Response.from_app(app, environ)
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/Werkzeug/werkzeug/wrappers.py", line 865, in from_app
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/Werkzeug/werkzeug/wrappers.py", line 57, in _run_wsgi_app
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/Werkzeug/werkzeug/test.py", line 871, in run_wsgi_app
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/zappa/zappa/middleware.py", line 78, in __call__
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1836, in __call__
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1820, in wsgi_app
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 271, in error_router
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1403, in handle_exception
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 268, in error_router
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1817, in wsgi_app
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1477, in full_dispatch_request
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 271, in error_router
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1381, in handle_user_exception
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 268, in error_router
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1475, in full_dispatch_request
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/app.py", line 1461, in dispatch_request
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 477, in wrapper
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-v6XvIH/flask/flask/views.py", line 84, in view
File "/private/var/folders/1j/5zcxjzkx29b8tfgrh2y90wt80000gn/T/pip-build-jvEYWI/flask-restful/flask_restful/__init__.py", line 587, in dispatch_request
File "/Users/notacat/src/aws-lambda/zappa/controllers/error_controller.py", line 15, in get
TestError: 'This is a test error'
Hard to understand stack trace from CloudWatch log:
...Rlc3RFcnJvcjogJ1RoaXMgaXMgYSB0ZXN0IGVycm9yJzxiciAvPjwvcHJlPg==:
Exception Traceback (most recent call last):
File "/var/task/handler.py", line 161, in lambda_handler return LambdaHandler.lambda_handler(event, context)
File "/var/task/handler.py", line 55, in lambda_handler return cls().handler(event, context)
File "/var/task/handler.py", line 155, in handler raise Exception(exception)
Exception: PCFET0NUWVBFIGh0bWw+NTAwLiBGcm9tIFphcHBhOiA8cHJlPidUaGlzIGl...