Attach prompt export values in module registry

internal/briefing/modules.go

@@ -21,6 +21,8 @@ type ModuleContext struct {
 
 type ModuleBuilder func(ModuleContext, any) (*module.Output, error)
 
+type ModulePromptExporter func(value any) (any, error)
+
 type ModuleDefinition struct {
 	ID                module.ID
 	StanzaName        string
@@ -31,6 +33,7 @@ type ModuleDefinition struct {
 	MissingData       module.MissingDataBehavior
 	AllowDuplicate    bool
 	Builder           ModuleBuilder
+	PromptExporter    ModulePromptExporter
 }
 
 type ModuleRegistry struct {
@@ -130,6 +133,15 @@ func (r ModuleRegistry) BuildModule(ctx ModuleContext, item module.ConfigItem) (
 	if output.StanzaName != definition.StanzaName {
 		return nil, fmt.Errorf("module %q produced stanza %q, want %q", definition.ID, output.StanzaName, definition.StanzaName)
 	}
+	if definition.PromptExporter == nil {
+		output.PromptValue = output.Value
+		return output, nil
+	}
+	promptValue, err := definition.PromptExporter(output.Value)
+	if err != nil {
+		return nil, fmt.Errorf("module %q stanza %q prompt export: %w", definition.ID, definition.StanzaName, err)
+	}
+	output.PromptValue = promptValue
 	return output, nil
 }
 

internal/briefing/modules_test.go

@@ -1,6 +1,8 @@
 package briefing
 
 import (
+	"encoding/json"
+	"errors"
 	"strings"
 	"testing"
 
@@ -40,6 +42,9 @@ func TestDefaultReportModulesBuildSnapshots(t *testing.T) {
 					t.Fatalf("BuildModule(%s) error = %v", item.ID, err)
 				}
 				if output != nil {
+					if output.DataPackageValue() == nil {
+						t.Fatalf("BuildModule(%s) data package value = nil", item.ID)
+					}
 					outputs = append(outputs, *output)
 				}
 			}
@@ -54,6 +59,173 @@ func TestDefaultReportModulesBuildSnapshots(t *testing.T) {
 	}
 }
 
+func TestModuleRegistryAddsPassThroughPromptValue(t *testing.T) {
+	registry, err := NewModuleRegistry([]ModuleDefinition{
+		{
+			ID:         module.Metadata,
+			StanzaName: "metadata",
+			Builder: func(ModuleContext, any) (*module.Output, error) {
+				return &module.Output{
+					ID:         module.Metadata,
+					StanzaName: "metadata",
+					Value:      testRegistryValue{Message: "rich"},
+				}, nil
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("NewModuleRegistry() error = %v", err)
+	}
+
+	output, err := registry.BuildModule(testRegistryModuleContext(), module.ConfigItem{ID: module.Metadata})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	if output == nil {
+		t.Fatal("BuildModule() output = nil, want output")
+	}
+	if output.PromptValue != output.Value {
+		t.Fatalf("PromptValue = %#v, want pass-through rich value %#v", output.PromptValue, output.Value)
+	}
+	if output.DataPackageValue() != output.Value {
+		t.Fatalf("DataPackageValue() = %#v, want rich value", output.DataPackageValue())
+	}
+}
+
+func TestModuleRegistryAddsCustomPromptValue(t *testing.T) {
+	registry, err := NewModuleRegistry([]ModuleDefinition{
+		{
+			ID:         module.Metadata,
+			StanzaName: "metadata",
+			Builder: func(ModuleContext, any) (*module.Output, error) {
+				return &module.Output{
+					ID:         module.Metadata,
+					StanzaName: "metadata",
+					Value:      testRegistryValue{Message: "rich"},
+				}, nil
+			},
+			PromptExporter: func(value any) (any, error) {
+				rich, ok := value.(testRegistryValue)
+				if !ok {
+					return nil, errors.New("unexpected rich value type")
+				}
+				return testRegistryValue{Message: rich.Message + " prompt"}, nil
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("NewModuleRegistry() error = %v", err)
+	}
+
+	output, err := registry.BuildModule(testRegistryModuleContext(), module.ConfigItem{ID: module.Metadata})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	got, ok := output.PromptValue.(testRegistryValue)
+	if !ok {
+		t.Fatalf("PromptValue type = %T, want testRegistryValue", output.PromptValue)
+	}
+	if got.Message != "rich prompt" {
+		t.Fatalf("PromptValue = %#v, want custom prompt value", got)
+	}
+	if output.DataPackageValue() != output.PromptValue {
+		t.Fatalf("DataPackageValue() = %#v, want custom prompt value", output.DataPackageValue())
+	}
+	if output.Value.(testRegistryValue).Message != "rich" {
+		t.Fatalf("Value = %#v, want rich value unchanged", output.Value)
+	}
+}
+
+func TestModuleRegistryWrapsPromptExporterErrors(t *testing.T) {
+	registry, err := NewModuleRegistry([]ModuleDefinition{
+		{
+			ID:         module.Metadata,
+			StanzaName: "metadata",
+			Builder: func(ModuleContext, any) (*module.Output, error) {
+				return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: testRegistryValue{Message: "rich"}}, nil
+			},
+			PromptExporter: func(any) (any, error) {
+				return nil, errors.New("unsupported value")
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("NewModuleRegistry() error = %v", err)
+	}
+
+	_, err = registry.BuildModule(testRegistryModuleContext(), module.ConfigItem{ID: module.Metadata})
+	if err == nil ||
+		!strings.Contains(err.Error(), `module "metadata" stanza "metadata" prompt export`) ||
+		!strings.Contains(err.Error(), "unsupported value") {
+		t.Fatalf("BuildModule() error = %v, want wrapped exporter error", err)
+	}
+}
+
+func TestModuleRegistryValidatesOutputBeforePromptExport(t *testing.T) {
+	called := false
+	registry, err := NewModuleRegistry([]ModuleDefinition{
+		{
+			ID:         module.Metadata,
+			StanzaName: "metadata",
+			Builder: func(ModuleContext, any) (*module.Output, error) {
+				return &module.Output{ID: module.CurrentConditions, StanzaName: "metadata", Value: testRegistryValue{Message: "rich"}}, nil
+			},
+			PromptExporter: func(any) (any, error) {
+				called = true
+				return testRegistryValue{Message: "prompt"}, nil
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("NewModuleRegistry() error = %v", err)
+	}
+
+	_, err = registry.BuildModule(testRegistryModuleContext(), module.ConfigItem{ID: module.Metadata})
+	if err == nil || !strings.Contains(err.Error(), `module "metadata" produced output id "current_conditions"`) {
+		t.Fatalf("BuildModule() error = %v, want output id validation error", err)
+	}
+	if called {
+		t.Fatal("PromptExporter called before output validation")
+	}
+}
+
+func TestModuleRegistryPromptValueIsNotPersistedInSnapshotJSON(t *testing.T) {
+	registry, err := NewModuleRegistry([]ModuleDefinition{
+		{
+			ID:         module.Metadata,
+			StanzaName: "metadata",
+			Builder: func(ModuleContext, any) (*module.Output, error) {
+				return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: testRegistryValue{Message: "rich"}}, nil
+			},
+			PromptExporter: func(any) (any, error) {
+				return testRegistryValue{Message: "prompt-only"}, nil
+			},
+		},
+	})
+	if err != nil {
+		t.Fatalf("NewModuleRegistry() error = %v", err)
+	}
+	output, err := registry.BuildModule(testRegistryModuleContext(), module.ConfigItem{ID: module.Metadata})
+	if err != nil {
+		t.Fatalf("BuildModule() error = %v", err)
+	}
+	snapshot, err := module.NewSnapshot([]module.Output{*output})
+	if err != nil {
+		t.Fatalf("NewSnapshot() error = %v", err)
+	}
+	data, err := json.Marshal(snapshot)
+	if err != nil {
+		t.Fatalf("Marshal() error = %v", err)
+	}
+	text := string(data)
+	if !strings.Contains(text, `"message":"rich"`) {
+		t.Fatalf("snapshot JSON missing rich value: %s", text)
+	}
+	if strings.Contains(text, "prompt-only") || strings.Contains(text, "promptValue") || strings.Contains(text, "PromptValue") {
+		t.Fatalf("snapshot JSON includes runtime-only prompt value: %s", text)
+	}
+}
+
 func TestHourlyDefaultModuleOptions(t *testing.T) {
 	definition := report.DefaultRegistry().MustLookup(report.Hourly)
 	var found bool
@@ -250,3 +422,15 @@ func TestSPCConvectiveOutlookDerivedRequirementAvailability(t *testing.T) {
 func noopModuleBuilder(ModuleContext, any) (*module.Output, error) {
 	return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: struct{}{}}, nil
 }
+
+type testRegistryValue struct {
+	Message string `json:"message"`
+}
+
+func testRegistryModuleContext() ModuleContext {
+	return ModuleContext{
+		Resolved: report.Resolved{
+			Definition: report.DefaultRegistry().MustLookup(report.Daily),
+		},
+	}
+}