Add a silent option to ignore warnings

[tgroshon]

Introduces a silent keyword argument to set the module into silent mode: read_dotenv(silent=True). Prevents UserWarning's.

fixes issue #12

[tgroshon]

I see the build problem and will address. Will replace with a regular kw arg and no * collector.

[merwok]

I was surprised by the warning. I had a server misconfiguration that made the env file not readable by my server process, and had to dig in logs to find that (the actual error happened a bit later when the code tries to read envvars). It would have been better for me to get an exception instead of a warning. So could we get three possible behaviours here: do nothing, warn, raise exception?

[tgroshon]

I like that idea, but I am not sure of the UI for that kind of behavior. Any ideas?

[merwok]

If you don’t mind ternary options, a UI could be:

• silent=True → do nothing
• silent=None → warn (default)
• silent=False → exception

Also, ignore_missing may be more obvious than silent.

[merwok]

A complementary idea would be to use logging instead of warnings. Logging is more appropriate according to https://docs.python.org/2/howto/logging.html#when-to-use-logging and easy to configure.

[tgroshon]

I also like the idea of replacing warnings with logging. Then a user could specify their log level easily in different environments (DEBUG in development or testing, WARNING in production, etc.).

[tgroshon]

i'm going to close this PR. We can move this discussion back over to issue #12 .