🎁 Buoy will float to branch for submodules other then root (#37)

* Collecting information about repository submodule

* Avoid to float to tags for non-root submodules within repo

* Add docs on using tags for Golang sub-modules

Author: cardil

buoy/README.md

@@ -121,15 +121,15 @@ knative.dev/eventing-github not ready for release because of the following depen
 If you need to see a more verbose output, use `--verbose`:
 
 ```
-$ bouy check $HOME/go/src/knative.dev/eventing-github/go.mod --domain knative.dev --release 0.18 --verbose
+$ buoy check $HOME/go/src/knative.dev/eventing-github/go.mod --domain knative.dev --release 0.18 --verbose
 knative.dev/eventing-github
 ✔ knative.dev/eventing@v0.18.0
 ✔ knative.dev/pkg@release-0.18
 ✔ knative.dev/serving@v0.18.0
 ✔ knative.dev/test-infra@release-0.18
 [exit status 0]
 
-$ bouy check $HOME/go/src/knative.dev/eventing-github/go.mod --domain knative.dev  --release 0.19 --verbose
+$ buoy check $HOME/go/src/knative.dev/eventing-github/go.mod --domain knative.dev  --release 0.19 --verbose
 knative.dev/eventing-github
 ✘ knative.dev/eventing@master
 ✘ knative.dev/pkg@master
@@ -161,6 +161,12 @@ Rulesets,
 
 For rulesets that that restrict the selection process, no ref is selected.
 
+NOTE: For Go modules that don't live on the root of their repository, the tagged
+releases are skipped. Golang requires the tags for sub-modules to be in form of
+"sub/v1.99.0" to be recognized by "go get" command. It's cumbersome to have
+both "v1.99.0" and "sub/v1.99.0", so float will skip looking for tags in this
+case.
+
 Usage:
   buoy float go.mod [flags]
 

buoy/commands/float.go

@@ -57,6 +57,12 @@ Rulesets,
   ReleaseOrBranch  tagged releases, release branch
 
 For rulesets that that restrict the selection process, no ref is selected.
+
+NOTE: For Go modules that don't live on the root of their repository, the tagged
+releases are skipped. Golang requires the tags for sub-modules to be in form of
+"sub/v1.99.0" to be recognized by "go get" command. It's cumbersome to have
+both "v1.99.0" and "sub/v1.99.0", so float will skip looking for tags in this
+case.
 `,
 		Args: cobra.ExactArgs(1),
 		PreRunE: func(cmd *cobra.Command, args []string) error {

go.mod

@@ -1,6 +1,6 @@
 module knative.dev/toolbox
 
-go 1.21
+go 1.22.7
 
 require (
 	cloud.google.com/go/storage v1.39.1

go.work

@@ -1,4 +1,4 @@
-go 1.21
+go 1.22.7
 
 use (
 	.

magetasks/go.mod

@@ -1,6 +1,6 @@
 module knative.dev/toolbox/magetasks
 
-go 1.21
+go 1.22.7
 
 require (
 	github.com/blang/semver/v4 v4.0.0

pkg/git/git.go

@@ -27,18 +27,21 @@ import (
 )
 
 // Repo is a simplified git remote, containing only the list of tags, default
-// branch and branches.
+// branch, branches, URL and submodule information.
 type Repo struct {
 	Ref           string
 	DefaultBranch string
 	Tags          []string
 	Branches      []string
+	Submodule     string
+	URL           string
 }
 
 // GetRepo will fetch a git repo and process it into a Repo object.
 func GetRepo(ref, url string) (*Repo, error) {
 	repo := new(Repo)
 	repo.Ref = ref
+	repo.URL = url
 
 	rem := git.NewRemote(memory.NewStorage(), &config.RemoteConfig{
 		Name: "origin",
@@ -91,28 +94,17 @@ func (rt RefType) String() string {
 }
 
 // BestRefFor Returns module@ref, isRelease based on the provided ruleset for
-// a this release.
+// this release.
 func (r *Repo) BestRefFor(release, moduleRelease semver.Version, ruleset RulesetType) (string, RefType) {
-	switch ruleset {
-	case AnyRule, ReleaseOrReleaseBranchRule, ReleaseRule:
-		var largest *semver.Version
-		// Look for a release.
-		for _, t := range r.Tags {
-			if sv, ok := normalizeTagVersion(t); ok {
-				v, _ := semver.Make(sv)
-				// Go does not understand how to fetch semver tags with pre or build tags, skip those.
-				if v.Pre != nil || v.Build != nil {
-					continue
-				}
-				if v.Major == moduleRelease.Major && v.Minor == moduleRelease.Minor {
-					if largest == nil || largest.LT(v) {
-						largest = &v
-					}
-				}
+	// don't look for tags if given module lives within repo as non-root member
+	if r.Submodule == "" {
+		switch ruleset {
+		case AnyRule, ReleaseOrReleaseBranchRule, ReleaseRule:
+			largest := r.lookForRelease(moduleRelease)
+			if largest != nil {
+				return fmt.Sprintf("%s@%s", r.Ref, ReleaseVersion(*largest)), ReleaseRef
 			}
-		}
-		if largest != nil {
-			return fmt.Sprintf("%s@%s", r.Ref, ReleaseVersion(*largest)), ReleaseRef
+		default:
 		}
 	}
 
@@ -134,18 +126,39 @@ func (r *Repo) BestRefFor(release, moduleRelease semver.Version, ruleset Ruleset
 		if largest != nil {
 			return fmt.Sprintf("%s@%s", r.Ref, ReleaseBranchVersion(*largest)), ReleaseBranchRef
 		}
+	default:
 	}
 
 	switch ruleset {
 	case AnyRule:
 		// Look for a Return default branch.
 		return fmt.Sprintf("%s@%s", r.Ref, r.DefaultBranch), DefaultBranchRef
+	default:
 	}
 
 	// No ref found with the provided rule
 	return r.Ref, NoRef
 }
 
+func (r *Repo) lookForRelease(moduleRelease semver.Version) *semver.Version {
+	var largest *semver.Version
+	for _, t := range r.Tags {
+		if sv, ok := normalizeTagVersion(t); ok {
+			v, _ := semver.Make(sv)
+			// Go does not understand how to fetch semver tags with pre or build tags, skip those.
+			if v.Pre != nil || v.Build != nil {
+				continue
+			}
+			if v.Major == moduleRelease.Major && v.Minor == moduleRelease.Minor {
+				if largest == nil || largest.LT(v) {
+					largest = &v
+				}
+			}
+		}
+	}
+	return largest
+}
+
 func normalizeTagVersion(v string) (string, bool) {
 	if strings.HasPrefix(v, "v") {
 		// No need to account for unicode widths.

pkg/git/git_test.go

@@ -22,6 +22,7 @@ import (
 	"github.com/blang/semver/v4"
 	fixtures "github.com/go-git/go-git-fixtures/v4"
 	"github.com/google/go-cmp/cmp"
+	"github.com/stretchr/testify/assert"
 )
 
 func TestGetRepo_BasicOne(t *testing.T) {
@@ -54,15 +55,17 @@ func TestGetRepo_Error(t *testing.T) {
 }
 
 func TestRepo_BestRefFor(t *testing.T) {
-	repo := &Repo{
+	repo := Repo{
 		Ref:           "ref",
 		DefaultBranch: "main",
 		Tags:          []string{"v0.1.0", "bar", "v0.2.0", "baz", "v0.2.1", "v0.2.2-rc.1", "v0.2.2+build", "foo"},
 		Branches:      []string{"release-0.1", "bar", "release-0.2", "baz", "main", "release-0.3", "release-1.0"},
 	}
+	submoduleRepo := repo
+	submoduleRepo.Submodule = "sub"
 
 	tests := map[string]struct {
-		repo          *Repo
+		repo          Repo
 		version       semver.Version
 		moduleVersion semver.Version
 		want          string
@@ -83,6 +86,13 @@ func TestRepo_BestRefFor(t *testing.T) {
 			release: ReleaseRef,
 			rule:    AnyRule,
 		},
+		"Any - v0.2 - with submodule": {
+			repo:    submoduleRepo,
+			version: semver.MustParse("0.2.0"),
+			want:    "ref@release-0.2",
+			release: ReleaseBranchRef,
+			rule:    AnyRule,
+		},
 		"Any - v0.3": {
 			repo:    repo,
 			version: semver.MustParse("0.3.0"),
@@ -120,6 +130,13 @@ func TestRepo_BestRefFor(t *testing.T) {
 			release: ReleaseRef,
 			rule:    ReleaseOrReleaseBranchRule,
 		},
+		"ReleaseOrReleaseBranch - v0.2 - Submodule": {
+			repo:    submoduleRepo,
+			version: semver.MustParse("0.2.0"),
+			want:    "ref@release-0.2",
+			release: ReleaseBranchRef,
+			rule:    ReleaseOrReleaseBranchRule,
+		},
 		"ReleaseOrReleaseBranch - v0.3": {
 			repo:    repo,
 			version: semver.MustParse("0.3.0"),
@@ -165,6 +182,13 @@ func TestRepo_BestRefFor(t *testing.T) {
 			release: ReleaseRef,
 			rule:    ReleaseRule,
 		},
+		"Release - v0.2 - Submodule": {
+			repo:    submoduleRepo,
+			version: semver.MustParse("0.2.0"),
+			want:    "ref",
+			release: NoRef,
+			rule:    ReleaseRule,
+		},
 		"Release - v0.3": {
 			repo:    repo,
 			version: semver.MustParse("0.3.0"),
@@ -231,12 +255,8 @@ func TestRepo_BestRefFor(t *testing.T) {
 				tt.moduleVersion = tt.version
 			}
 			got, release := tt.repo.BestRefFor(tt.version, tt.moduleVersion, tt.rule)
-			if got != tt.want {
-				t.Errorf("repo.BestRefFor() got ref = %v, want %v", got, tt.want)
-			}
-			if release != tt.release {
-				t.Errorf("repo.BestRefFor() got isRelease = %v, want %v", got, tt.want)
-			}
+			assert.Equal(t, tt.want, got)
+			assert.Equal(t, tt.release, release)
 		})
 	}
 }

pkg/golang/goimport.go

@@ -71,10 +71,21 @@ func metaContent(doc *html.Node, name string) (string, error) {
 	return "", fmt.Errorf("missing <meta name=%s> in the node tree", name)
 }
 
+// Importer imports the metadata for given URL of a Go module.
+type Importer struct {
+	*http.Client
+}
+
+var defaultImporter = Importer{}
+
 // GetMetaImport fetches and parses header tags named go-import into a
 // MetaImport object.
-func GetMetaImport(url string) (*MetaImport, error) {
-	resp, err := http.Get(url)
+func (i Importer) GetMetaImport(url string) (*MetaImport, error) {
+	cl := i.Client
+	if cl == nil {
+		cl = http.DefaultClient
+	}
+	resp, err := cl.Get(url)
 	if err != nil {
 		return nil, err
 	}
@@ -98,7 +109,8 @@ func GetMetaImport(url string) (*MetaImport, error) {
 }
 
 // ModuleToRepo resolves a go module name to a remote git repo.
-func ModuleToRepo(module string) (*git.Repo, error) {
+func (i Importer) ModuleToRepo(module string) (*git.Repo, error) {
+	originalModule := module
 	// If module has more than 1 domain + 2 paths (e.g. github.com/blang/semver/v4),
 	// make it 1 domain + 2 paths. Otherwise, it fails to fetch go import on GetMetaImport().
 	m := strings.Split(module, "/")
@@ -107,7 +119,7 @@ func ModuleToRepo(module string) (*git.Repo, error) {
 	}
 
 	url := fmt.Sprintf("https://%s?go-get=1", module)
-	meta, err := GetMetaImport(url)
+	meta, err := i.GetMetaImport(url)
 	if err != nil {
 		return nil, fmt.Errorf("unable to fetch go import %s: %w", url, err)
 	}
@@ -116,5 +128,24 @@ func ModuleToRepo(module string) (*git.Repo, error) {
 		return nil, errors.New("unknown VCS: " + meta.VCS)
 	}
 
-	return git.GetRepo(module, meta.RepoRoot)
+	repo, err := git.GetRepo(module, meta.RepoRoot)
+	if err != nil {
+		return nil, err
+	}
+	if meta.Prefix != originalModule {
+		repo.Submodule = strings.TrimPrefix(
+			strings.TrimPrefix(originalModule, meta.Prefix), "/")
+	}
+	return repo, nil
+}
+
+// GetMetaImport fetches and parses header tags named go-import into a
+// MetaImport object.
+func GetMetaImport(url string) (*MetaImport, error) {
+	return defaultImporter.GetMetaImport(url)
+}
+
+// ModuleToRepo resolves a go module name to a remote git repo.
+func ModuleToRepo(module string) (*git.Repo, error) {
+	return defaultImporter.ModuleToRepo(module)
 }