Logging: don't import grpc if grpc disabled #12
Description
I noticed the Stackdriver module supports usage with grpc installed, which is great. However it currently still tries to import _gapic even if grpc usage is explicitly disabled via env var. This causes some additional latency for cli & serverless usage.
$ cat x.py
import time
import sys
def main():
mcount = len(sys.modules)
t = time.time()
from google.cloud.logging import Client
print("modules:%d %0.2f sec" % (
len(sys.modules) - mcount, time.time() - t))
if __name__ == '__main__':
main()
so this tries two tests, one with the default google.cloud.logging.client imports, and one where the try/except around the _gapic imports is replaced with the except clause ie modification of these lines
https://github.com/googleapis/google-cloud-python/blob/master/logging/google/cloud/logging/client.py#L21
default import
(custodian) bash-3.2$ python x.py
modules:576 0.51 sec
(custodian) bash-3.2$ python x.py
modules:576 0.50 sec
(custodian) bash-3.2$ python x.py
modules:576 0.44 sec
(custodian) bash-3.2$ python x.py
modules:576 0.47 sec
Disable import of _gapi in
(custodian) bash-3.2$ python x.py
modules:510 0.38 sec
(custodian) bash-3.2$ python x.py
modules:510 0.37 sec
(custodian) bash-3.2$ python x.py
modules:510 0.37 sec
(custodian) bash-3.2$ python x.py
modules:510 0.38 sec
(custodian) bash-3.2$ python x.py
modules:510 0.37 sec
so baseline improvement for cli / serverless execution of ~100ms. for serverless environments this effect is more pronounced I've noticed.
Ideally the DISABLE_GRPC environment could be checked before attempting to import the _gapic modules.