Makefile changes to allow easy builds with or without vendoring. Also fixes version bug for both cases.

[pstibrany]

This PR modifies Makefile to handle builds with or without vendoring.

It uses GOMOD env. variable to set vendoring or not. Content of GOMOD, if defined, is passed to -mod parameter of Go tools. If not defined, it defaults to “vendor”.

Since vendoring or not vendoring modifies import path of common.Version (from Prometheus) as visible by linker, versioning information is now stored directly in loki.Version, and passed to common.Version on start.

[slim-bean]

LGTM!

[joe-elliott]

Unfortunately this is only a partial fix. Linting is controlled here:

https://github.com/grafana/loki/blob/master/.golangci.yml#L7

and this bit of black magic was necessary to make go generate play nice:

https://github.com/grafana/loki/blob/master/pkg/promtail/server/ui/doc.go#L10

[pstibrany]

Thanks for pointing out more places.

Unfortunately this is only a partial fix. Linting is controlled here:

https://github.com/grafana/loki/blob/master/.golangci.yml#L7

Not sure if I understand it correctly, but I think this doesn't run from Makefile, does it?

and this bit of black magic was necessary to make go generate play nice:

https://github.com/grafana/loki/blob/master/pkg/promtail/server/ui/doc.go#L10

Fixed now. It uses go generate's support for $ENV variables expansion.

See this output with vendoring enabled:

$ VENDOR=true make all
>> writing assets
GOFLAGS="-mod=vendor" GOOS=darwin go generate -x -v ./pkg/promtail/server/ui
pkg/promtail/server/ui/doc.go
go run -tags=dev assets_generate.go -build_flags="-mod=vendor"
writing assets_vfsdata.go

and with vendoring off:

$ VENDOR=false make all
>> writing assets
GOFLAGS="" GOOS=darwin go generate -x -v ./pkg/promtail/server/ui
pkg/promtail/server/ui/doc.go
go run -tags=dev assets_generate.go -build_flags=""
writing assets_vfsdata.go

[pstibrany]

Unfortunately this is only a partial fix. Linting is controlled here:
https://github.com/grafana/loki/blob/master/.golangci.yml#L7

Not sure if I understand it correctly, but I think this doesn't run from Makefile, does it?

Oh, it does. OK. Let's see if we can do anything about it.

[pstibrany]

Sent PR to GolangCI to support passing modules download mode as a command line argument.

golangci/golangci-lint#781

[pstibrany]

Required golangci-lint change is now available in 1.21.0. Due to upcoming changes to go modules, I will rework this little bit to allow any GOMOD=<mode> instead of using VENDOR flag only. Empty will disable -mod parameter, non empty value will use that as a value for -mod parameter. Will default to vendor.

Link to Go modules change in Go 1.14: golang/go#33848

[slim-bean]

@pstibrany can you revisit this since we've updated to go mod and also updated golangci-lint?

[pstibrany]

@pstibrany can you revisit this since we've updated to go mod and also updated golangci-lint?

@slim-bean sure... I have switched to mostly just running go build manually, without Makefile, most of the time, so it hasn't been pressing issue for me, but I can finish it.

[pstibrany]

Instead of using VENDOR=true or VENDOR=false, it now uses GOMOD env. variable, which can be set to empty string, "vendor", "readonly" and in Go 1.14 also to "mod". If not defined at all, Makefile will use "vendor".

Non empty values are passed to -mod parameter to Go tools, and --modules-download-mode parameter for golangci-cli linting tool.

Note that empty string, i.e. no -mod parameter means different things in Go 1.13 and Go 1.14. In Go 1.13 it means no vendoring, in 1.14 it will default to vendoring, if vendor dir is present and go.mod specifies go 1.14. But at least with GOMOD support in Makefile, now it's easy to set for the whole build. [Details here: https://github.com/golang/go/issues/33848#issuecomment-537222782]

[daixiang0]

any update?

[pstibrany]

This is ready for another review.

[cyriltovena]

nice work ! lgtm