This introduces the terraform state list command to list the resources
within a state. This is the first of many state management commands to
come into 0.7.
This is the first command of many to come that is considered a
"plumbing" command within Terraform (see "plumbing vs porcelain":
http://git.661346.n2.nabble.com/what-are-plumbing-and-porcelain-td2190639.html).
As such, this PR also introduces a bunch of groundwork to support
plumbing commands.
The main changes:
- Main command output is changed to split "common" and "uncommon"
commands.
- mitchellh/cli is updated to support nested subcommands, since
terraform state list is a nested subcommand.
- terraform.StateFilter is introduced as a way in core to filter/search
the state files. This is very basic currently but I expect to make it
more advanced as time goes on.
- terraform state list command is introduced to list resources in a
state. This can take a series of arguments to filter this down.
Known issues, or things that aren't done in this PR on purpose:
- Unit tests for terraform state list are on the way. Unit tests for the
core changes are all there.
This brings in the go-colorable library when running on Windows in order
to output console colors correctly instead of leaving the codes in place
as is currently the case.
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.
