Working extension invocation.

[n3wscott]

I moved the cmd setup into pkg and decoupled the commands from os.* This should make testing much easier when there are tests.

The change adds kubectl/git style plugins. For example:

⦿ ls ~/bin/ | grep ko
ko-scott

⦿ cat ~/bin/ko-scott
#! /bin/bash
echo "hello, extension!"

⦿ go run cmd/ko/main.go scott
hello, extension!

[n3wscott]

look!!! 🎉

[n3wscott]

filestuff.go.... really?

[codecov-io]

Codecov Report

Merging #292 into master will decrease coverage by 0.66%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master    #292      +/-   ##
=========================================
- Coverage   50.46%   49.8%   -0.67%     
=========================================
  Files          61      62       +1     
  Lines        2776    2813      +37     
=========================================
  Hits         1401    1401              
- Misses       1150    1187      +37     
  Partials      225     225

Impacted Files	Coverage Δ
pkg/ko/cmd/filestuff.go	0% <ø> (ø)
pkg/ko/cmd/local.go	0% <ø> (ø)
pkg/ko/cmd/resolve.go	0% <ø> (ø)
pkg/ko/cmd/config.go	30.3% <ø> (ø)
pkg/ko/cmd/flatname.go	0% <ø> (ø)
pkg/ko/cmd/publish.go	9.3% <ø> (ø)
pkg/ko/cmd/extensions.go	0% <0%> (ø)
pkg/ko/cmd/commands.go	0% <0%> (ø)
pkg/ko/cmd/cmd.go	0% <0%> (ø)
... and 1 more

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[imjasonh]

Is there a particular plugin you're hoping to enable with this? ko doesn't do a lot today, I'm not sure it needs a plugin story.

[n3wscott]

@imjasonh, This one: https://github.com/n3wscott/kopond/tree/master/extensions

[imjasonh]

What benefit do we expect ko-foo to get from being callable as ko foo? AFAICT the only context you'd gain from even knowing the user also uses ko is the presence of KO_DOCKER_REPO and .ko.yaml. Why not just ask the user to install and use ko-foo, renamed to just foo?

Supporting a plugin model means defining and supporting the plugin integration points. It means we probably can't add global flags or new subcommands or change the format of .ko.yaml without considering all possible plugins and taking care about versioning.

ko hasn't even had an official release yet. This feels premature to me.

[n3wscott]

Perhaps you want the stdin/out refactors?

I am thinking I will make kubectl plugin that uses ko

[n3wscott]

OK as an update, check this workflow out: https://github.com/n3wscott/kopond/tree/master/kubectl