[athena] fixing logger format string and using lambda alias for invocation

[ryandeivert]

to: @austinbyers
cc: @airbnb/streamalert-maintainers
size: small
related to: #806

Background

@austinbyers observed the following stack trace:

%d format: a number is required, not unicode: TypeError
Traceback (most recent call last):
File "/var/task/stream_alert/athena_partition_refresh/main.py", line 212, in handler
AthenaRefresher().run(event)
File "/var/task/stream_alert/athena_partition_refresh/main.py", line 180, in run
sqs_rec['attributes']['SentTimestamp'])
File "/usr/lib64/python2.7/logging/__init__.py", line 1155, in debug
self._log(DEBUG, msg, args, **kwargs)
File "/usr/lib64/python2.7/logging/__init__.py", line 1286, in _log
self.handle(record)
File "/usr/lib64/python2.7/logging/__init__.py", line 1296, in handle
self.callHandlers(record)
File "/usr/lib64/python2.7/logging/__init__.py", line 1336, in callHandlers
hdlr.handle(record)
File "/usr/lib64/python2.7/logging/__init__.py", line 759, in handle
self.emit(record)
File "/var/runtime/awslambda/bootstrap.py", line 446, in emit
msg = self.format(record)
File "/usr/lib64/python2.7/logging/__init__.py", line 734, in format
return fmt.format(record)
File "/usr/lib64/python2.7/logging/__init__.py", line 465, in format
record.message = record.getMessage()
File "/usr/lib64/python2.7/logging/__init__.py", line 329, in getMessage
msg = msg % self.args
TypeError: %d format: a number is required, not unicode

Changes

• Fixing above error by using %s format string
• Updating event source mapping to invoke production alias instead of $LATEST

Testing

Deployed in test account

[coveralls]

Coverage remained the same at 96.961% when pulling 549dc7c on ryandeivert-athena-logger into b0612e5 on master.

[austinbyers]

🙌