Example of using rules_go with go workspaces

Go added workspaces in 1.18 and support was subsequently to gazelle with bazel-gazelle#1250.

This example shows how to used go workspaces with gazelle and rules_go.

Dependency versions in go.mod & go.sum through the workspace defined in go.work should be kept in sync by running go work sync.

Legacy build

In this example module1 and module2 are both runnable main packages.

You can build & run with regular go tooling from the root of the go_workspaces example directory as follows,

$ go run ./module1
Calling cmd.Execute()!
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and

$ go run ./module2
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Using gazelle

gazelle update-repos

To update the list of go_repositories() in deps.bzl from go.mod & corresponding go.sum files listed in go.work run:

bazel run //:gazelle-update-repos

gazelle update BUILD files

To update & create go targets throughout the repository run

bazel run //:gazelle

Running with Bazel

To run the two go_binary targets generated by gazelle call,

$ bazel run //module1:module1
INFO: Analyzed target //module1:module1 (0 packages loaded, 0 targets configured).
INFO: Found 1 target...
Target //module1:module1 up-to-date:
  bazel-bin/module1/module1_/module1
INFO: Elapsed time: 0.167s, Critical Path: 0.00s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action
INFO: Build completed successfully, 1 total action
Calling cmd.Execute()!
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and

$ bazel run //module2:module2
INFO: Analyzed target //module2:module2 (0 packages loaded, 0 targets configured).
INFO: Found 1 target...
Target //module2:module2 up-to-date:
  bazel-bin/module2/module2_/module2
INFO: Elapsed time: 0.184s, Critical Path: 0.00s
INFO: 1 process: 1 internal.
INFO: Build completed successfully, 1 total action
INFO: Build completed successfully, 1 total action
sunrise 2022-09-26 11:09:12 +0000 UTC sunset 2022-09-26 23:08:26 +0000 UTC