[bug] go report tells code needs improvement

[allencloud]

Issue Description

In README.md if we click go report, we will turn to link https://goreportcard.com/report/github.com/alibaba/pouch

There we found that there are several parts to be improve, such as:

go vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string.
pouch/cli/pull.go
Line 94: error: unrecognized printf verb 'r' (vet)
Line 102: error: unrecognized printf verb 'r' (vet)
Line 109: error: unrecognized printf verb 'r' (vet)

and

Gocyclo calculates cyclomatic complexities of functions in Go source code. The cyclomatic complexity of a function is calculated according to the following rules: 1 is the base complexity of a function +1 for each 'if', 'for', 'case', '&&' or '||' Go Report Card warns on functions with cyclomatic complexity > 15.
pouch/volume/core.go
Line 95: warning: cyclomatic complexity 16 of function (*Core).CreateVolume() is high (> 15) (gocyclo)
pouch/ctrd/image.go
Line 130: warning: cyclomatic complexity 22 of function (*Client).fetchProgress() is high (> 15) (gocyclo)

and

Misspell Finds commonly misspelled English words
pouch/test/pouch_api_help_test.go
Line 15: warning: "begining" is a misspelling of "beginning" (misspell)
pouch/test/pouch_cli_help_test.go
Line 17: warning: "begining" is a misspelling of "beginning" (misspell)
pouch/test/pouch_cli_version_test.go
Line 17: warning: "begining" is a misspelling of "beginning" (misspell)
pouch/volume/driver/driver.go
Line 150: warning: "registed" is a misspelling of "registered" (misspell)

and so so.

These all needs fixed.

[allencloud]

Could you help to solve this for project? @Letty5411

[Letty5411]

@allencloud OK

[allencloud]

I reassigned this issue to @zhubingbing , and maybe bingbing can help. @Letty5411

[zhubingbing]

1. Issue Description

go vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string.
pouch/cli/pull.go
Line 94: error: unrecognized printf verb 'r' (vet)
Line 102: error: unrecognized printf verb 'r' (vet)
Line 109: error: unrecognized printf verb 'r' (vet)

i think fmt.Sprintf formate don’t have “r” parameter, so go vet report this issue.
if an operand implements the Formatter interface, it will be invoked. Formatter provides fine control of formatting.（https://golang.org/pkg/fmt/#Fprintf）
and bar.go(https://github.com/containerd/containerd/blob/master/progress/bar.go#L21) to realize formatter interface. so i thinks there's no problems with this code .

[allencloud]

Actually with my own go vet on my local machine, it will report no error:

pouch (master) $ go vet cli/pull.go
pouch (master) $ go version
go version go1.8.3 darwin/amd64
pouch (master) $

So maybe we can ignore this, and please move on on your work. @zhubingbing
Thanks a lot.