Demonstrate main-relative companion loading

examples/consumers/main_relative.go

@@ -0,0 +1,47 @@
+package consumers
+
+import (
+	"io/fs"
+	"path/filepath"
+
+	configkit "go.maximumdirect.net/configkit"
+)
+
+// CompanionConfig demonstrates independently bundled and operator prompt tiers.
+type CompanionConfig struct {
+	Mode    string            `yaml:"mode"`
+	Prompts []CompanionPrompt `yaml:"prompts"`
+}
+
+type CompanionPrompt struct {
+	ID   string `yaml:"id"`
+	Text string `yaml:"text"`
+	Note string `yaml:"note"`
+}
+
+// LoadCompanionConfig discovers a main file and binds operator imports and the
+// selected overlay to its directory while retaining the embedded catalog tier.
+func LoadCompanionConfig(mainPath, overlay string) (*configkit.Result[CompanionConfig], error) {
+	files, err := fs.Sub(bundledFiles, "testdata/main-relative-bundle")
+	if err != nil {
+		return nil, err
+	}
+	bundle := configkit.NewFilesystem("bundled catalog", files)
+	absolute, err := filepath.Abs(mainPath)
+	if err != nil {
+		return nil, err
+	}
+	declarations := map[string]any{"config": map[string]any{"imports": []any{
+		map[string]any{"path": "prompts.yml", "destination": []any{"prompts"}, "placement": "sequence-item"},
+		map[string]any{"dir": "operator", "recursive": true, "pattern": []any{"*.yml", "*.yaml"}, "destination": []any{"prompts"}, "placement": "sequence-item"},
+	}}}
+	main := configkit.SearchConfig("", configkit.Searches(configkit.SearchPaths(absolute)), configkit.SearchOptions{Required: true})
+	return configkit.LoadLayered(configkit.Input{Source: main}, configkit.LayeredOptions[CompanionConfig]{
+		Underlays: []configkit.Underlay{
+			{Inputs: []configkit.Input{{Source: bundle.File("catalog.yml")}}},
+			{Inputs: []configkit.Input{{Source: configkit.Mapping("operator imports", declarations), Imports: true, MainRelative: configkit.MainRelative()}}},
+		},
+		Overlay:    overlay,
+		Definition: configkit.Definition[CompanionConfig]{SequenceIdentities: []configkit.SequenceIdentity{configkit.SequenceIdentityAt(configkit.Keys("prompts"), "id")}},
+	})
+}