feat: export genesis in simapp v2 (#21199)

Co-authored-by: marbar3778 <marbar3778@yahoo.com>

runtime/v2/app.go

@@ -79,6 +79,11 @@ func (a *App[T]) LoadHeight(height uint64) error {
 	return a.db.LoadVersion(height)
 }
 
+// LoadLatestHeight loads the latest height.
+func (a *App[T]) LoadLatestHeight() (uint64, error) {
+	return a.db.GetLatestVersion()
+}
+
 // Close is called in start cmd to gracefully cleanup resources.
 func (a *App[T]) Close() error {
 	return nil

runtime/v2/builder.go

@@ -69,7 +69,7 @@ func (a *AppBuilder[T]) RegisterModules(modules map[string]appmodulev2.AppModule
 
 // RegisterStores registers the provided store keys.
 // This method should only be used for registering extra stores
-// wiich is necessary for modules that not registered using the app config.
+// which is necessary for modules that not registered using the app config.
 // To be used in combination of RegisterModules.
 func (a *AppBuilder[T]) RegisterStores(keys ...string) {
 	a.app.storeKeys = append(a.app.storeKeys, keys...)
@@ -175,6 +175,19 @@ func (a *AppBuilder[T]) Build(opts ...AppBuilderOption[T]) (*App[T], error) {
 			}
 			return nil
 		},
+		ExportGenesis: func(ctx context.Context, version uint64) ([]byte, error) {
+			genesisJson, err := a.app.moduleManager.ExportGenesisForModules(ctx)
+			if err != nil {
+				return nil, fmt.Errorf("failed to export genesis: %w", err)
+			}
+
+			bz, err := json.Marshal(genesisJson)
+			if err != nil {
+				return nil, fmt.Errorf("failed to marshal genesis: %w", err)
+			}
+
+			return bz, nil
+		},
 	}
 
 	appManager, err := appManagerBuilder.Build()

runtime/v2/manager.go

@@ -203,16 +203,13 @@ func (m *MM[T]) ExportGenesisForModules(
 		return nil, err
 	}
 
-	type genesisResult struct {
-		bz  json.RawMessage
-		err error
-	}
-
 	type ModuleI interface {
 		ExportGenesis(ctx context.Context) (json.RawMessage, error)
 	}
 
-	channels := make(map[string]chan genesisResult)
+	genesisData := make(map[string]json.RawMessage)
+
+	// TODO: make async export genesis https://github.com/cosmos/cosmos-sdk/issues/21303
 	for _, moduleName := range modulesToExport {
 		mod := m.modules[moduleName]
 		var moduleI ModuleI
@@ -221,27 +218,16 @@ func (m *MM[T]) ExportGenesisForModules(
 			moduleI = module.(ModuleI)
 		} else if module, hasABCIGenesis := mod.(appmodulev2.HasGenesis); hasABCIGenesis {
 			moduleI = module.(ModuleI)
+		} else {
+			continue
 		}
 
-		channels[moduleName] = make(chan genesisResult)
-		go func(moduleI ModuleI, ch chan genesisResult) {
-			jm, err := moduleI.ExportGenesis(ctx)
-			if err != nil {
-				ch <- genesisResult{nil, err}
-				return
-			}
-			ch <- genesisResult{jm, nil}
-		}(moduleI, channels[moduleName])
-	}
-
-	genesisData := make(map[string]json.RawMessage)
-	for moduleName := range channels {
-		res := <-channels[moduleName]
-		if res.err != nil {
-			return nil, fmt.Errorf("genesis export error in %s: %w", moduleName, res.err)
+		res, err := moduleI.ExportGenesis(ctx)
+		if err != nil {
+			return nil, err
 		}
 
-		genesisData[moduleName] = res.bz
+		genesisData[moduleName] = res
 	}
 
 	return genesisData, nil