Go modules

Transcript

1. Go modules WARSAW, MAY 22 2019 Oleg Kovalov Allegro Twitter: oleg_kovalov Github: cristaloleg
2. Me - Gopher for ~4 years - Open-source contributor - Engineer at allegro.pl core team Twitter: @oleg_kovalov Github: @cristaloleg
3. Long story short Image credit: ©Istockphoto/JamesBrey time
4. - GOPATH Pre-modules era (2012-2018)
5. - GOPATH - godep - gopkg.in - glide Pre-modules era (2012-2018)
6. - GOPATH - godep - gopkg.in - glide - vendor dir Pre-modules era (2012-2018)
7. - GOPATH - godep - gopkg.in - glide - vendor dir - dep Pre-modules era (2012-2018)
8. - GOPATH - godep - gopkg.in - glide - vendor dir - dep - ... Pre-modules era (2012-2018)
9. Go modules
10. - Modules Go modules
11. - Modules - Semantic versioning Go modules
12. - Modules - Semantic versioning - Import compatibility rule Go modules
13. - Modules - Semantic versioning - Import compatibility rule - go.mod Go modules
14. - A module is a collection of Go packages that are versioned as a single unit What is a module?
15. - A module is a collection of Go packages that are versioned as a single unit - (often) a single version-control repository is a single module What is a module?
16. What is a module? - A module is a tree/directory of Go source files with a go.mod file in the root directory
17. What is a module? - A module is a tree/directory of Go source files with a go.mod file in the root directory - Can live outside of a GOPATH
18. Semantic versioning (http://semver.org)
19. If an old and a new package have the same import path, the new package must be backwards-compatible with the old package. Import compatibility rule
20. GO111MODULE=auto go build ./… GO111MODULE
21. GO111MODULE=auto go build ./… - Inside GOPATH defaults to old 1.10 behavior (ignoring modules) GO111MODULE
22. GO111MODULE GO111MODULE=auto go build ./… - Inside GOPATH defaults to old 1.10 behavior (ignoring modules) - Outside GOPATH while inside a file tree with a go.mod = defaults to modules behavior
23. - auto(default) - on - off GO111MODULE
24. GO111MODULE - auto(default) - on - off $ export GO111MODULE=on $ go build ./...
25. Changes to go get
26. # same (@latest is default for 'go get') $ go get github.com/gorilla/mux@latest Changes to go get
27. # same (@latest is default for 'go get') $ go get github.com/gorilla/mux@latest # records v1.6.2 $ go get github.com/gorilla/mux@v1.6.2 Changes to go get
28. # same (@latest is default for 'go get') $ go get github.com/gorilla/mux@latest # records v1.6.2 $ go get github.com/gorilla/mux@v1.6.2 # records v1.6.2 $ go get github.com/gorilla/mux@e3702bed2 Changes to go get
29. # same (@latest is default for 'go get') $ go get github.com/gorilla/mux@latest # records v1.6.2 $ go get github.com/gorilla/mux@v1.6.2 # records v1.6.2 $ go get github.com/gorilla/mux@e3702bed2 # records v0.0.0-20180517173623-c85619274f5d $ go get github.com/gorilla/mux@c856192 Changes to go get
30. # same (@latest is default for 'go get') $ go get github.com/gorilla/mux@latest # records v1.6.2 $ go get github.com/gorilla/mux@v1.6.2 # records v1.6.2 $ go get github.com/gorilla/mux@e3702bed2 # records v0.0.0-20180517173623-c85619274f5d $ go get github.com/gorilla/mux@c856192 # records current meaning of master $ go get github.com/gorilla/mux@master Changes to go get
31. $ mkdir /mygo/hello $ cd /mygo/hello $ go mod init github.com/golang/hello go: creating new go.mod: module github.com/golang/hello $ ls go.mod $ cat go.mod module github.com/golang/hello Let’s start
32. $ git clone https://github.com/go-gitea/gitea Cloning into gitea... $ cd gitea Convert to modules
33. $ git clone https://github.com/go-gitea/gitea Cloning into gitea... $ cd gitea $ go mod init go: creating new go.mod: module github.com/go-gitea/gitea go: copying requirements from Gopkg.lock Convert to modules
34. $ git clone https://github.com/go-gitea/gitea Cloning into gitea... $ cd gitea $ go mod init go: creating new go.mod: module github.com/go-gitea/gitea go: copying requirements from Gopkg.lock $ go mod tidy go: extracting github.com/PuerkitoBio/goquery v1.5.0 go: extracting github.com/blevesearch/bleve v0.7.0 go: finding github.com/go-macaron/session/redis latest go: finding github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57 go: finding golang.org/x/lint v0.0.0-20190301231843-5614ed5bae6f go: finding github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b go: finding golang.org/x/lint v0.0.0-20190227174305-5b3e6a55c961 go: finding golang.org/x/time v0.0.0-20181108054448-85acf8d2951c go: downloading github.com/facebookgo/grace v0.0.0-20180706040059-75cf19382434 Convert to modules
35. How to read go.mod
36. module github.com/hashicorp/consul ... How to read go.mod
37. module github.com/hashicorp/consul go 1.12 ... How to read go.mod
38. module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 ... How to read go.mod
39. module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 github.com/DataDog/datadog-go v0.0.0-20160329135253-cc2f4770f4d6 // indirect ... How to read go.mod
40. module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 github.com/DataDog/datadog-go v0.0.0-20160329135253-cc2f4770f4d6 // indirect ... How to read go.mod
41. module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 github.com/DataDog/datadog-go v0.0.0-20160329135253-cc2f4770f4d6 // indirect github.com/go-redis/redis v6.15.2+incompatible ... ) ... How to read go.mod
42. How to read go.mod module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 github.com/DataDog/datadog-go v0.0.0-20160329135253-cc2f4770f4d6 // indirect github.com/go-redis/redis v6.15.2+incompatible ... ) replace github.com/hashicorp/consul/api => ./api replace github.com/hashicorp/consul/sdk => ./sdk ...
43. How to read go.mod module github.com/hashicorp/consul go 1.12 require ( github.com/NYTimes/gziphandler v1.0.1 github.com/DataDog/datadog-go v0.0.0-20160329135253-cc2f4770f4d6 // indirect github.com/go-redis/redis v6.15.2+incompatible ... ) replace github.com/hashicorp/consul/api => ./api replace github.com/hashicorp/consul/sdk => ./sdk exclude github.com/not-a-hacker/supergeil v1270.0.1
44. How to read go.sum
45. How to read go.sum
46. cloud.google.com/go v0.26.0 h1:e0WKqKTd5BnrG8aKH3J3h+QvEIQtSUcf2n5UZ5ZgLtQ= cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw= How to read go.sum
47. cloud.google.com/go v0.26.0 h1:e0WKqKTd5BnrG8aKH3J3h+QvEIQtSUcf2n5UZ5ZgLtQ= cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw= github.com/Azure/azure-sdk-for-go v16.0.0+incompatible h1:gr1qKY/Ll72VjFTZmaBwRK1yQHAxCnV25ekOKroc9ws= github.com/Azure/azure-sdk-for-go v16.0.0+incompatible/go.mod h1:9XXNKU+eRnpl9moKnB4QOLf1HestfXbmab5FXxiDBjc= How to read go.sum
48. cloud.google.com/go v0.26.0 h1:e0WKqKTd5BnrG8aKH3J3h+QvEIQtSUcf2n5UZ5ZgLtQ= cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw= github.com/Azure/azure-sdk-for-go v16.0.0+incompatible h1:gr1qKY/Ll72VjFTZmaBwRK1yQHAxCnV25ekOKroc9ws= github.com/Azure/azure-sdk-for-go v16.0.0+incompatible/go.mod h1:9XXNKU+eRnpl9moKnB4QOLf1HestfXbmab5FXxiDBjc= // you might want to use go mod verify How to read go.sum
49. Usage: go mod <command> [arguments] The commands are: download download modules to local cache edit edit go.mod from tools or scripts fix make go.mod semantically consistent graph print module requirement graph init initialize new module in current directory tidy add missing and remove unused modules vendor make vendored copy of dependencies verify verify dependencies have expected content why explain why packages or modules are needed go mod commands
50. # go and get a repo $ go get github.com/go-gitea/gitea $ cd ~/go/src/github.com/go-gitea/gitea go mod why
51. # go and get a repo $ go get github.com/go-gitea/gitea $ cd ~/go/src/github.com/go-gitea/gitea # set a env var and check why do we use this dependency $ export GO111MODULE=on go mod why
52. # go and get a repo $ go get github.com/go-gitea/gitea $ cd ~/go/src/github.com/go-gitea/gitea # set a env var and check why do we use this dependency $ export GO111MODULE=on $ go mod why github.com/RoaringBitmap/roaring # github.com/RoaringBitmap/roaring code.gitea.io/gitea/modules/indexer github.com/blevesearch/bleve github.com/blevesearch/bleve/index/scorch github.com/RoaringBitmap/roaring go mod why
53. FROM golang ENV GO111MODULE=on Dockerfile
54. FROM golang ENV GO111MODULE=on WORKDIR /app COPY go.mod . COPY go.sum . Dockerfile
55. FROM golang ENV GO111MODULE=on WORKDIR /app COPY go.mod . COPY go.sum . RUN go mod download COPY . . Dockerfile
56. Dockerfile FROM golang ENV GO111MODULE=on WORKDIR /app COPY go.mod . COPY go.sum . RUN go mod download COPY . . RUN CGO_ENABLED=0 GOOS=linux go build -a -o app.exec ./... EXPOSE 8000 ENTRYPOINT ["./app.exec"]
57. Use local changes
58. Use local changes - Сhange in go.mod manually
59. Use local changes - Сhange in go.mod manually - go mod edit -replace ‘foo.com/bar=../bar’
60. Use local changes - Сhange in go.mod manually - go mod edit -replace ‘foo.com/bar=../bar’ - or use awesome gohack tool by Roger Peppe
61. # install $ go get github.com/rogpeppe/gohack gohack by Roger Peppe
62. # install $ go get github.com/rogpeppe/gohack $ gohack get example.com/foo/bar # will clone repo into $HOME/gohack/example.com/foo/bar # will add: replace example.com/foo/bar /home/rog/gohack/example.com/foo/bar gohack by Roger Peppe
63. # install $ go get github.com/rogpeppe/gohack $ gohack get example.com/foo/bar # will clone repo into $HOME/gohack/example.com/foo/bar # will add: replace example.com/foo/bar /home/rog/gohack/example.com/foo/bar $ cat go.mod replace example.com/foo/bar => /home/rog/gohack/example.com/foo/bar gohack by Roger Peppe
64. gohack by Roger Peppe # install $ go get github.com/rogpeppe/gohack $ gohack get example.com/foo/bar # will clone repo into $HOME/gohack/example.com/foo/bar # will add: replace example.com/foo/bar /home/rog/gohack/example.com/foo/bar $ cat go.mod replace example.com/foo/bar => /home/rog/gohack/example.com/foo/bar # to remove specific replace: $ gohack undo example.com/foo/bar # to remove all replaces: $ gohack undo
65. Go Proxy
66. Go Proxy https://proxy.golang.org https://github.com/gomods/athens - export GOPROXY=my.proxy.com - go get github.com/foo/bar
67. Future
68. - Enabled by default Future
69. - Enabled by default - More robust ecosystem Future
70. - Enabled by default - More robust ecosystem - More secure Future
71. - Enabled by default - More robust ecosystem - More secure - More tools understand modules Future
72. - Enabled by default - More robust ecosystem - More secure - More tools understand modules - No vendor (perhaps?) Future
73. - Enabled by default - More robust ecosystem - More secure - More tools understand modules - No vendor (perhaps?) - Less “but it works on my machine!” Future
74. Why package management is hard?
75. That’s all folks Thank you Questions? Twitter: @oleg_kovalov Github: @cristaloleg