The filtering for other log levels is unreliable and glitchy because it's
trying to infer information from the log stream that isn't reliably
represented.
Although the previous commit has improved the situation somewhat, it is
still a tricky and unreliable heuristic, so worth a warning to anyone who
is reading such a log that if they see something confusing it could be
a result of the heuristic not working fully.
In order to make this work reasonably we can't avoid using some funny
heuristics, which are somewhat reasonable to apply within the context of
Terraform itself but would not be good to add to the general "logutils".
Specifically, this is adding the additional heuristic that lines starting
with spaces are continuation lines and so should inherit the log level
of the most recent non-continuation line.
Set the default log package output to iotuil.Discard during tests if the
`-v` flag isn't set. If we are verbose, then apply the filter according
to the TF_LOG env variable.
This should be quite helpful in debugging aws-sdk-go operations.
Required some tweaking around the `helper/logging` functions to expose an
`IsDebugOrHigher()` helper for us to use.
We weren't doing any log setup for acceptance tests, which made it
difficult to wrangle log output in CI.
This moves the log setup functions we use in `main` over into a helper
package so we can use them for acceptance tests as well.
This means that acceptance tests will by default be a _lot_ quieter,
only printing out actual test output. Setting `TF_LOG=trace` will
restore the full prior noise level.
Only minor behavior change is to make `ioutil.Discard` the default
return value rather than a `nil` that needs to be checked for.
Martin Atkins