refactor(librarian): migrate map-based source options to SourceConfig (#4354)

Reapply "refactor(librarian): migrate map-based source options to
SourceConfig" (#4339). This reverts commit
dadc578.

This originally failed because google-cloud-rust/librarian.yaml still
contained a root_name: conformance-root; however, the -root suffix is no
longer needed after we moved to the SourceConfig struct. We'll cleanup
conformance-root.

Fixes #3863 
Fixes #4300

Author: jameslynnwu

doc/config-schema.md

@@ -270,7 +270,7 @@ This document describes the schema for the librarian.yaml.
 | `name_overrides` | string | Contains codec-level overrides for type and service names. |
 | `output` | string | Is the directory where generated code is written (e.g., "src/storage/src/generated/gapic"). |
 | `post_process_protos` | string | Contains code to post-process generated protos. |
-| `root_name` | string | Is the key for the root directory in the source map. It overrides the default root, googleapis-root, used by the rust+prost generator. |
+| `root_name` | string | Is the key for the root directory in the source map. It overrides the default root, googleapis, used by the rust+prost generator. |
 | `routing_required` | bool | Indicates whether routing is required. |
 | `service_config` | string | Is the path to the service config file. |
 | `skipped_ids` | list of string | Is a list of proto IDs to skip in generation. |

internal/config/language.go

@@ -163,7 +163,7 @@ type RustModule struct {
 	PostProcessProtos string `yaml:"post_process_protos,omitempty"`
 
 	// RootName is the key for the root directory in the source map.
-	// It overrides the default root, googleapis-root, used by the rust+prost generator.
+	// It overrides the default root, googleapis, used by the rust+prost generator.
 	RootName string `yaml:"root_name,omitempty"`
 
 	// RoutingRequired indicates whether routing is required.

internal/librarian/dart/codec.go

@@ -17,7 +17,6 @@ package dart
 import (
 	"errors"
 	"fmt"
-	"strings"
 
 	"github.com/googleapis/librarian/internal/config"
 	"github.com/googleapis/librarian/internal/serviceconfig"
@@ -33,10 +32,10 @@ func toModelConfig(library *config.Library, ch *config.API, sources *sidekickcon
 		return nil, fmt.Errorf("%w, got %q", errInvalidSpecificationFormat, library.SpecificationFormat)
 	}
 
-	src := addLibraryRoots(library, sources)
+	src := sidekickconfig.NewSourceConfig(*sources, library.Roots)
 
 	if library.Dart != nil && library.Dart.IncludeList != nil {
-		src["include-list"] = strings.Join(library.Dart.IncludeList, ",")
+		src.IncludeList = library.Dart.IncludeList
 	}
 	root := sources.Googleapis
 	if ch.Path == "schema/google/showcase/v1beta1" {
@@ -128,36 +127,3 @@ func buildCodec(library *config.Library) map[string]string {
 	}
 	return codec
 }
-
-// TODO(https://github.com/googleapis/librarian/issues/3863): remove this function once we removed sidekick config.
-func addLibraryRoots(library *config.Library, sources *sidekickconfig.Sources) map[string]string {
-	src := make(map[string]string)
-	if library.Rust == nil {
-		library.Rust = &config.RustCrate{}
-	}
-
-	if len(library.Roots) == 0 && sources.Googleapis != "" {
-		// Default to googleapis if no roots are specified.
-		src["googleapis-root"] = sources.Googleapis
-		src["roots"] = "googleapis"
-	} else {
-		src["roots"] = strings.Join(library.Roots, ",")
-		rootMap := map[string]struct {
-			path string
-			key  string
-		}{
-			"googleapis":   {path: sources.Googleapis, key: "googleapis-root"},
-			"discovery":    {path: sources.Discovery, key: "discovery-root"},
-			"showcase":     {path: sources.Showcase, key: "showcase-root"},
-			"protobuf-src": {path: sources.ProtobufSrc, key: "protobuf-src-root"},
-			"conformance":  {path: sources.Conformance, key: "conformance-root"},
-		}
-		for _, root := range library.Roots {
-			if r, ok := rootMap[root]; ok && r.path != "" {
-				src[r.key] = r.path
-			}
-		}
-	}
-
-	return src
-}

internal/librarian/dart/codec_test.go

@@ -296,9 +296,11 @@ func TestToModelConfig(t *testing.T) {
 			want: &parser.ModelConfig{
 				SpecificationFormat: config.SpecProtobuf,
 				SpecificationSource: "google/cloud/functions/v2",
-				Source: map[string]string{
-					"googleapis-root": googleapisDir,
-					"roots":           "googleapis",
+				Source: sidekickconfig.SourceConfig{
+					Sources: sidekickconfig.Sources{
+						Googleapis: googleapisDir,
+					},
+					ActiveRoots: []string{"googleapis"},
 				},
 				Codec:    map[string]string{},
 				Override: api.ModelOverride{},
@@ -316,9 +318,11 @@ func TestToModelConfig(t *testing.T) {
 			want: &parser.ModelConfig{
 				SpecificationFormat: config.SpecProtobuf,
 				SpecificationSource: "google/cloud/functions/v2",
-				Source: map[string]string{
-					"googleapis-root": googleapisDir,
-					"roots":           "googleapis",
+				Source: sidekickconfig.SourceConfig{
+					Sources: sidekickconfig.Sources{
+						Googleapis: googleapisDir,
+					},
+					ActiveRoots: []string{"googleapis"},
 				},
 				Codec: map[string]string{},
 				Override: api.ModelOverride{
@@ -340,9 +344,11 @@ func TestToModelConfig(t *testing.T) {
 			want: &parser.ModelConfig{
 				SpecificationFormat: config.SpecProtobuf,
 				SpecificationSource: "google/cloud/functions/v2",
-				Source: map[string]string{
-					"googleapis-root": googleapisDir,
-					"roots":           "googleapis",
+				Source: sidekickconfig.SourceConfig{
+					Sources: sidekickconfig.Sources{
+						Googleapis: googleapisDir,
+					},
+					ActiveRoots: []string{"googleapis"},
 				},
 				Codec: map[string]string{},
 				Override: api.ModelOverride{
@@ -384,9 +390,11 @@ func TestToModelConfig(t *testing.T) {
 			want: &parser.ModelConfig{
 				SpecificationFormat: config.SpecProtobuf,
 				SpecificationSource: "google/cloud/functions/v2",
-				Source: map[string]string{
-					"googleapis-root": googleapisDir,
-					"roots":           "googleapis",
+				Source: sidekickconfig.SourceConfig{
+					Sources: sidekickconfig.Sources{
+						Googleapis: googleapisDir,
+					},
+					ActiveRoots: []string{"googleapis"},
 				},
 				Override: api.ModelOverride{
 					Title: "library-title-override",
@@ -442,72 +450,3 @@ func TestToModelConfig(t *testing.T) {
 		})
 	}
 }
-
-func TestAddLibraryRoots(t *testing.T) {
-	for _, test := range []struct {
-		name    string
-		library *config.Library
-		source  *sidekickconfig.Sources
-		want    map[string]string
-	}{
-		{
-			name:    "empty roots",
-			library: &config.Library{},
-			source: &sidekickconfig.Sources{
-				Googleapis: "example/path",
-			},
-			want: map[string]string{
-				"googleapis-root": "example/path",
-				"roots":           "googleapis",
-			},
-		},
-		{
-			name: "non existed sources",
-			library: &config.Library{
-				Roots: []string{"non-existed", "googleapis"},
-			},
-			source: &sidekickconfig.Sources{
-				Googleapis:  "example/path",
-				ProtobufSrc: "protobuf/path",
-			},
-			want: map[string]string{
-				"googleapis-root": "example/path",
-				"roots":           "non-existed,googleapis",
-			},
-		},
-		{
-			name: "all sources",
-			library: &config.Library{
-				Roots: []string{
-					"conformance",
-					"discovery",
-					"googleapis",
-					"protobuf-src",
-					"showcase",
-				},
-			},
-			source: &sidekickconfig.Sources{
-				Conformance: "conformance/path",
-				Discovery:   "discovery/path",
-				Googleapis:  "googleapis/path",
-				ProtobufSrc: "protobuf/path",
-				Showcase:    "showcase/path",
-			},
-			want: map[string]string{
-				"conformance-root":  "conformance/path",
-				"discovery-root":    "discovery/path",
-				"googleapis-root":   "googleapis/path",
-				"protobuf-src-root": "protobuf/path",
-				"showcase-root":     "showcase/path",
-				"roots":             "conformance,discovery,googleapis,protobuf-src,showcase",
-			},
-		},
-	} {
-		t.Run(test.name, func(t *testing.T) {
-			got := addLibraryRoots(test.library, test.source)
-			if diff := cmp.Diff(test.want, got); diff != "" {
-				t.Errorf("mismatch (-want +got):\n%s", diff)
-			}
-		})
-	}
-}

internal/librarian/rust/codec.go

@@ -31,7 +31,7 @@ func libraryToModelConfig(library *config.Library, ch *config.API, sources *side
 		specFormat = library.SpecificationFormat
 	}
 
-	src := addLibraryRoots(library, sources)
+	src := sidekickconfig.NewSourceConfig(*sources, library.Roots)
 	root := sources.Googleapis
 	if ch.Path == "schema/google/showcase/v1beta1" {
 		root = sources.Showcase
@@ -222,10 +222,14 @@ func formatPackageDependency(dep *config.RustPackageDependency) string {
 }
 
 func moduleToModelConfig(library *config.Library, module *config.RustModule, sources *sidekickconfig.Sources) (*parser.ModelConfig, error) {
-	src := addLibraryRoots(library, sources)
+	src := sidekickconfig.NewSourceConfig(*sources, library.Roots)
 	var title string
-	if module.APIPath != "" && src["roots"] == "googleapis" {
-		api, err := serviceconfig.Find(sources.Googleapis, module.APIPath, config.LanguageRust)
+	if module.APIPath != "" && len(src.ActiveRoots) == 1 && src.ActiveRoots[0] == "googleapis" {
+		root := sources.Googleapis
+		if module.APIPath == "schema/google/showcase/v1beta1" {
+			root = sources.Showcase
+		}
+		api, err := serviceconfig.Find(root, module.APIPath, config.LanguageRust)
 		if err != nil {
 			return nil, fmt.Errorf("failed to find service config for %q: %w", module.APIPath, err)
 		}
@@ -243,7 +247,7 @@ func moduleToModelConfig(library *config.Library, module *config.RustModule, sou
 		specificationFormat = module.SpecificationFormat
 	}
 	if module.IncludeList != "" {
-		src["include-list"] = module.IncludeList
+		src.IncludeList = strings.Split(module.IncludeList, ",")
 	}
 	modelCfg := &parser.ModelConfig{
 		Language:            language,
@@ -323,36 +327,3 @@ func buildModuleCodec(library *config.Library, module *config.RustModule) map[st
 	}
 	return codec
 }
-
-// TODO(https://github.com/googleapis/librarian/issues/3863): remove this function once we removed sidekick config.
-func addLibraryRoots(library *config.Library, sources *sidekickconfig.Sources) map[string]string {
-	src := make(map[string]string)
-	if library.Rust == nil {
-		library.Rust = &config.RustCrate{}
-	}
-
-	if len(library.Roots) == 0 && sources.Googleapis != "" {
-		// Default to googleapis if no roots are specified.
-		src["googleapis-root"] = sources.Googleapis
-		src["roots"] = "googleapis"
-	} else {
-		src["roots"] = strings.Join(library.Roots, ",")
-		rootMap := map[string]struct {
-			path string
-			key  string
-		}{
-			"googleapis":   {path: sources.Googleapis, key: "googleapis-root"},
-			"discovery":    {path: sources.Discovery, key: "discovery-root"},
-			"showcase":     {path: sources.Showcase, key: "showcase-root"},
-			"protobuf-src": {path: sources.ProtobufSrc, key: "protobuf-src-root"},
-			"conformance":  {path: sources.Conformance, key: "conformance-root"},
-		}
-		for _, root := range library.Roots {
-			if r, ok := rootMap[root]; ok && r.path != "" {
-				src[r.key] = r.path
-			}
-		}
-	}
-
-	return src
-}