Linkerd2: Improve Go Report Card

[siggy]

We are getting an A+ on Go Report Card, but there is still a lot to improve:
~https://goreportcard.com/report/github.com/runconduit/conduit~
https://goreportcard.com/report/github.com/linkerd/linkerd2

We should consider these changes, and also add a badge to README.md.

[klingerf]

Hmm, looks like almost all of the issues in the repo could be found with the golint tool. We should get in the habit of running that.

[pcalcado]

Should we create a precommit.sh file or something that does a standardized go test ./... && go vet ./... && golint? Also could be the script travis runs

[klingerf]

Yeah, I'd be in favor of auto-running some form of linting, but I'd like to investigate if the linting rules are configurable before we start failing builds. There are a few things turned up by the linter that don't seem important to me, such as:

var mockApiClient should be mockAPIClient

[klingerf]

Heh, and this one:

func name will be used as version.VersionFlag by other packages, and that stutters; consider calling this Flag

[pcalcado]

I am very easygoing with these things, I can definitely live with the silly ones if it gives us a standardised and well-supported way to check for more interesting things.

[rafaeljesus]

IMHO I am not really about skipping these lint errors, it's pretty handy for writing idiomatic golang code ^.^

Also it might be required if you decide to add it at awesome-go list

[siggy]

Taking this a bit further, #2284 introduced a .golangci.yml file, which specifies which golangci-lint checkers to run.

To help improve the codebase further, we should work towards reducing the number of checkers in the disable list. Essentially repeat this pattern:

1. remove an item from the disable list
2. run bin/lint, observe errors
3. fix errors until bin/lint succeeds

[grampelberg]

@siggy this issue doesn't feel particularly actionable at this point (and there's a ton of awesome work that's already been done). WDYT about closing this out and opening up directed issues for what's remaining?

[siggy]

@grampelberg I'm fine with closing this one.

Note that we lost our perfect gofmt score recently:
https://goreportcard.com/report/github.com/linkerd/linkerd2#gofmt
This may have happened when we changed our lint config, probably worth a new issue to track this.

[grampelberg]

I was wondering about that. Thanks!