feat(runtime/v2): store loader on simappv2 (#21704)

Co-authored-by: marbar3778 <[email protected]>
(cherry picked from commit 7d6ff0d)

# Conflicts:
#	CHANGELOG.md
#	runtime/v2/app.go
#	runtime/v2/module.go
#	runtime/v2/store.go

Author: randygrok

Diff for: CHANGELOG.md

@@ -40,6 +40,14 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 Every module contains its own CHANGELOG.md. Please refer to the module you are interested in.
 
+<<<<<<< HEAD
+=======
+### Features
+
+* (baseapp) [#20291](https://github.com/cosmos/cosmos-sdk/pull/20291) Simulate nested messages.
+* (runtime) [#21704](https://github.com/cosmos/cosmos-sdk/pull/21704) Add StoreLoader in simappv2.
+
+>>>>>>> 7d6ff0df5 (feat(runtime/v2): store loader on simappv2 (#21704))
 ### Improvements
 
 * (genutil) [#21701](https://github.com/cosmos/cosmos-sdk/pull/21701) Improved error messages for genesis validation.

Diff for: runtime/store.go

@@ -9,6 +9,7 @@ import (
 	"cosmossdk.io/core/store"
 	storetypes "cosmossdk.io/store/types"
 
+	"github.com/cosmos/cosmos-sdk/baseapp"
 	sdk "github.com/cosmos/cosmos-sdk/types"
 )
 
@@ -181,3 +182,23 @@ func (s kvStoreAdapter) ReverseIterator(start, end []byte) dbm.Iterator {
 func KVStoreAdapter(store store.KVStore) storetypes.KVStore {
 	return &kvStoreAdapter{store}
 }
+
+// UpgradeStoreLoader is used to prepare baseapp with a fixed StoreLoader
+// pattern. This is useful for custom upgrade loading logic.
+func UpgradeStoreLoader(upgradeHeight int64, storeUpgrades *store.StoreUpgrades) baseapp.StoreLoader {
+	return func(ms storetypes.CommitMultiStore) error {
+		if upgradeHeight == ms.LastCommitID().Version+1 {
+			// Check if the current commit version and upgrade height matches
+			if len(storeUpgrades.Deleted) > 0 || len(storeUpgrades.Added) > 0 {
+				stup := &storetypes.StoreUpgrades{
+					Added:   storeUpgrades.Added,
+					Deleted: storeUpgrades.Deleted,
+				}
+				return ms.LoadLatestVersionAndUpgrade(stup)
+			}
+		}
+
+		// Otherwise load default store loader
+		return baseapp.DefaultStoreLoader(ms)
+	}
+}

Diff for: runtime/v2/app.go

@@ -0,0 +1,125 @@
+package runtime
+
+import (
+	"encoding/json"
+	"errors"
+	"slices"
+
+	gogoproto "github.com/cosmos/gogoproto/proto"
+
+	runtimev2 "cosmossdk.io/api/cosmos/app/runtime/v2"
+	"cosmossdk.io/core/registry"
+	"cosmossdk.io/core/transaction"
+	"cosmossdk.io/log"
+	"cosmossdk.io/server/v2/appmanager"
+	"cosmossdk.io/server/v2/stf"
+)
+
+// App is a wrapper around AppManager and ModuleManager that can be used in hybrid
+// app.go/app config scenarios or directly as a servertypes.Application instance.
+// To get an instance of *App, *AppBuilder must be requested as a dependency
+// in a container which declares the runtime module and the AppBuilder.Build()
+// method must be called.
+//
+// App can be used to create a hybrid app.go setup where some configuration is
+// done declaratively with an app config and the rest of it is done the old way.
+// See simapp/app_v2.go for an example of this setup.
+type App[T transaction.Tx] struct {
+	*appmanager.AppManager[T]
+
+	// app manager dependencies
+	stf                *stf.STF[T]
+	msgRouterBuilder   *stf.MsgRouterBuilder
+	queryRouterBuilder *stf.MsgRouterBuilder
+	db                 Store
+
+	// app configuration
+	logger log.Logger
+	config *runtimev2.Module
+
+	// modules configuration
+	storeKeys          []string
+	interfaceRegistrar registry.InterfaceRegistrar
+	amino              registry.AminoRegistrar
+	moduleManager      *MM[T]
+
+	// GRPCMethodsToMessageMap maps gRPC method name to a function that decodes the request
+	// bytes into a gogoproto.Message, which then can be passed to appmanager.
+	GRPCMethodsToMessageMap map[string]func() gogoproto.Message
+
+	storeLoader StoreLoader
+}
+
+// Name returns the app name.
+func (a *App[T]) Name() string {
+	return a.config.AppName
+}
+
+// Logger returns the app logger.
+func (a *App[T]) Logger() log.Logger {
+	return a.logger
+}
+
+// ModuleManager returns the module manager.
+func (a *App[T]) ModuleManager() *MM[T] {
+	return a.moduleManager
+}
+
+// DefaultGenesis returns a default genesis from the registered modules.
+func (a *App[T]) DefaultGenesis() map[string]json.RawMessage {
+	return a.moduleManager.DefaultGenesis()
+}
+
+// SetStoreLoader sets the store loader.
+func (a *App[T]) SetStoreLoader(loader StoreLoader) {
+	a.storeLoader = loader
+}
+
+// LoadLatest loads the latest version.
+func (a *App[T]) LoadLatest() error {
+	return a.storeLoader(a.db)
+}
+
+// LoadHeight loads a particular height
+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
+}
+
+// GetStoreKeys returns all the app store keys.
+func (a *App[T]) GetStoreKeys() []string {
+	return a.storeKeys
+}
+
+// UnsafeFindStoreKey fetches a registered StoreKey from the App in linear time.
+// NOTE: This should only be used in testing.
+func (a *App[T]) UnsafeFindStoreKey(storeKey string) (string, error) {
+	i := slices.IndexFunc(a.storeKeys, func(s string) bool { return s == storeKey })
+	if i == -1 {
+		return "", errors.New("store key not found")
+	}
+
+	return a.storeKeys[i], nil
+}
+
+// GetStore returns the app store.
+func (a *App[T]) GetStore() Store {
+	return a.db
+}
+
+func (a *App[T]) GetAppManager() *appmanager.AppManager[T] {
+	return a.AppManager
+}
+
+func (a *App[T]) GetGPRCMethodsToMessageMap() map[string]func() gogoproto.Message {
+	return a.GRPCMethodsToMessageMap
+}