feat: support in-place migration ordering (backport cosmos#10614) (co…

…smos#10890)

* feat: support in-place migration ordering (cosmos#10614)

## Description

Closes: cosmos#10604

---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
please add links to any relevant follow up issues.*

I have...

- [x] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [ ] provided a link to the relevant issue or specification
- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

*All items are required. Please add a note if the item is not applicable and please add
your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

(cherry picked from commit da92921)

# Conflicts:
#	CHANGELOG.md
#	docs/core/upgrade.md
#	types/errors/errors.go
#	types/module/module.go

* conflict fix

* Add Features section

* fix conflicts

Co-authored-by: Robert Zaremba <robert@zaremba.ch>

CHANGELOG.md

@@ -39,7 +39,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 ### State Machine Breaking
 
-- [#10833](https://github.com/cosmos/cosmos-sdk/pull/10833) fix reported tx gas used when block gas limit exceeded.
+* [#10833](https://github.com/cosmos/cosmos-sdk/pull/10833) fix reported tx gas used when block gas limit exceeded.
 * (auth) [\#10536](https://github.com/cosmos/cosmos-sdk/pull/10536]) Enable `SetSequence` for `ModuleAccount`.
 * (store) [#10218](https://github.com/cosmos/cosmos-sdk/pull/10218) Charge gas even when there are no entries while seeking.
 * (store) [#10247](https://github.com/cosmos/cosmos-sdk/pull/10247) Charge gas for the key length in gas meter.
@@ -48,6 +48,10 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * (auth) [\#10022](https://github.com/cosmos/cosmos-sdk/pull/10022) `AuthKeeper` interface in `x/auth` now includes a function `HasAccount`.
 
+### Features
+
+* [\#10614](https://github.com/cosmos/cosmos-sdk/pull/10614) Support in-place migration ordering
+
 ### Improvements
 
 * [\#10486](https://github.com/cosmos/cosmos-sdk/pull/10486) store/cachekv's `Store.Write` conservatively

docs/core/upgrade.md

@@ -20,15 +20,15 @@ This document provides steps to use the In-Place Store Migrations upgrade method
 
 ## Tracking Module Versions
 
-Each module gets assigned a consensus version by the module developer. The consensus version serves as the breaking change version of the module. The SDK keeps track of all module consensus versions in the x/upgrade `VersionMap` store. During an upgrade, the difference between the old `VersionMap` stored in state and the new `VersionMap` is calculated by the Cosmos SDK. For each identified difference, the module-specific migrations are run and the respective consensus version of each upgraded module is incremented.
+Each module gets assigned a consensus version by the module developer. The consensus version serves as the breaking change version of the module. The Cosmos SDK keeps track of all module consensus versions in the x/upgrade `VersionMap` store. During an upgrade, the difference between the old `VersionMap` stored in state and the new `VersionMap` is calculated by the Cosmos SDK. For each identified difference, the module-specific migrations are run and the respective consensus version of each upgraded module is incremented.
 
 ### Consensus Version
 
 The consensus version is defined on each app module by the module developer and serves as the breaking change version of the module. The consensus version informs the SDK on which modules need to be upgraded. For example, if the bank module was version 2 and an upgrade introduces bank module 3, the SDK upgrades the bank module and runs the "version 2 to 3" migration script.
 
 ### Version Map
 
-The version map is a mapping of module names to consensus versions. The map is persisted to x/upgrade's state for use during in-place migrations. When migrations finish, the updated version map is persisted to state.
+The version map is a mapping of module names to consensus versions. The map is persisted to x/upgrade's state for use during in-place migrations. When migrations finish, the updated version map is persisted in the state.
 
 ## Upgrade Handlers
 
@@ -46,14 +46,14 @@ Inside these functions, you must perform any upgrade logic to include in the pro
 
 ## Running Migrations
 
-Migrations are run inside of an `UpgradeHandler` using  `app.mm.RunMigrations(ctx, cfg, vm)`. The `UpgradeHandler` functions describe the functionality to occur during an upgrade. The `RunMigration` function loops through the `VersionMap` argument and runs the migration scripts for all versions that are less than the versions of the new binary app module. After the migrations are finished, a new `VersionMap` is returned to persist the upgraded module versions to state.
+Migrations are run inside of an `UpgradeHandler` using `app.mm.RunMigrations(ctx, cfg, vm)`. The `UpgradeHandler` functions describe the functionality to occur during an upgrade. The `RunMigration` function loops through the `VersionMap` argument and runs the migration scripts for all versions that are less than the versions of the new binary app module. After the migrations are finished, a new `VersionMap` is returned to persist the upgraded module versions to state.
 
 ```go
 cfg := module.NewConfigurator(...)
 app.UpgradeKeeper.SetUpgradeHandler("my-plan", func(ctx sdk.Context, plan upgradetypes.Plan, fromVM module.VersionMap) (module.VersionMap, error) {
 
     // ...
-    // do upgrade logic
+    // additional upgrade logic
     // ...
 
     // returns a VersionMap with the updated module ConsensusVersions
@@ -65,24 +65,9 @@ To learn more about configuring migration scripts for your modules, see the [Mod
 
 ### Order Of Migrations
 
-All migrations are run in alphabetical order, except `x/auth` which is run the last, because of state dependencies between modules (you can read more in [issue #10606](https://github.com/cosmos/cosmos-sdk/issues/10606)). If you want to change the order of migration then you can run migrations in multiple stages. __Please beware that this is hacky, and make sure you understand what you are doing before running such migrations in production_. For example, you want to run `foo` last:
+By default, all migrations are run in module name alphabetical ascending order, except `x/auth` which is run last. The reason is state dependencies between x/auth and other modules (you can read more in [issue #10606](https://github.com/cosmos/cosmos-sdk/issues/10606)).
 
-```go
-app.UpgradeKeeper.SetUpgradeHandler("my-plan", func(ctx sdk.Context, plan upgradetypes.Plan, fromVM module.VersionMap)  (module.VersionMap, error) {
-
-    fooFrom := fromVM["foo"]
-    fromVM["foo"] = foo.AppModule{}.ConsensusVersion()
-    toVM, err := app.mm.RunMigrations(ctx, cfg, fromVM)
-    if err != nil {
-        return toVM, err
-    }
-
-    stage2 := module.VersionMap{"foo": fooFrom}
-    _, err = app.mm.RunMigrations(ctx, cfg, stage2)
-
-    return toVM, err
-})
-```
+If you want to change the order of migration then you should call `app.mm.SetOrderMigrations(module1, module2, ...)` in your app.go file. The function will panic if you forget to include a module in the argument list.
 
 ## Adding New Modules During Upgrades
 
@@ -125,7 +110,7 @@ func (app *MyApp) InitChainer(ctx sdk.Context, req abci.RequestInitChain) abci.R
 
 This information is used by the Cosmos SDK to detect when modules with newer versions are introduced to the app.
 
-For a new module `foo`, `InitGenesis` is called by the `RunMigration` only when there is a new module registered in the module manager and there is no `foo` entry in the `fromVM` registered in the state. Therefore, if you want to skip `InitGenesis` when a new module is added to the app, then you should set its module version in `fromVM` to the module package consensus version:
+For a new module `foo`, `InitGenesis` is called by `RunMigration` only when `foo` is registered in the module manager but it's not set in the `fromVM`. Therefore, if you want to skip `InitGenesis` when a new module is added to the app, then you should set its module version in `fromVM` to the module consensus version:
 
 ```go
 app.UpgradeKeeper.SetUpgradeHandler("my-plan", func(ctx sdk.Context, plan upgradetypes.Plan, fromVM module.VersionMap) (module.VersionMap, error) {

simapp/app.go

@@ -359,6 +359,9 @@ func NewSimApp(
 		paramstypes.ModuleName, upgradetypes.ModuleName, vestingtypes.ModuleName,
 	)
 
+	// Uncomment if you want to set a custom migration order here.
+	// app.mm.SetOrderMigrations(custom order)
+
 	app.mm.RegisterInvariants(&app.CrisisKeeper)
 	app.mm.RegisterRoutes(app.Router(), app.QueryRouter(), encodingConfig.Amino)
 	app.configurator = module.NewConfigurator(app.appCodec, app.MsgServiceRouter(), app.GRPCQueryRouter())

types/errors/errors.go

@@ -141,12 +141,12 @@ var (
 	// Examples: not DB domain error, file writing etc...
 	ErrIO = Register(RootCodespace, 39, "Internal IO error")
 
+	// ErrAppConfig defines an error occurred if min-gas-prices field in BaseConfig is empty.
+	ErrAppConfig = Register(RootCodespace, 40, "error in app.toml")
+
 	// ErrPanic is only set when we recover from a panic, so we know to
 	// redact potentially sensitive system info
 	ErrPanic = Register(UndefinedCodespace, 111222, "panic")
-
-	// ErrAppConfig defines an error occurred if min-gas-prices field in BaseConfig is empty.
-	ErrAppConfig = Register(RootCodespace, 40, "error in app.toml")
 )
 
 // Register returns an error instance that should be used as the base for

types/module/module.go

@@ -230,6 +230,7 @@ type Manager struct {
 	OrderExportGenesis []string
 	OrderBeginBlockers []string
 	OrderEndBlockers   []string
+	OrderMigrations    []string
 }
 
 // NewManager creates a new Manager object
@@ -253,28 +254,35 @@ func NewManager(modules ...AppModule) *Manager {
 
 // SetOrderInitGenesis sets the order of init genesis calls
 func (m *Manager) SetOrderInitGenesis(moduleNames ...string) {
-	m.checkForgottenModules("SetOrderInitGenesis", moduleNames)
+	m.assertNoForgottenModules("SetOrderInitGenesis", moduleNames)
 	m.OrderInitGenesis = moduleNames
 }
 
 // SetOrderExportGenesis sets the order of export genesis calls
 func (m *Manager) SetOrderExportGenesis(moduleNames ...string) {
-	m.checkForgottenModules("SetOrderExportGenesis", moduleNames)
+	m.assertNoForgottenModules("SetOrderExportGenesis", moduleNames)
 	m.OrderExportGenesis = moduleNames
 }
 
 // SetOrderBeginBlockers sets the order of set begin-blocker calls
 func (m *Manager) SetOrderBeginBlockers(moduleNames ...string) {
-	m.checkForgottenModules("SetOrderBeginBlockers", moduleNames)
+	m.assertNoForgottenModules("SetOrderBeginBlockers", moduleNames)
 	m.OrderBeginBlockers = moduleNames
 }
 
 // SetOrderEndBlockers sets the order of set end-blocker calls
 func (m *Manager) SetOrderEndBlockers(moduleNames ...string) {
-	m.checkForgottenModules("SetOrderEndBlockers", moduleNames)
+	m.assertNoForgottenModules("SetOrderEndBlockers", moduleNames)
 	m.OrderEndBlockers = moduleNames
 }
 
+// SetOrderMigrations sets the order of migrations to be run. If not set
+// then migrations will be run with an order defined in `DefaultMigrationsOrder`.
+func (m *Manager) SetOrderMigrations(moduleNames ...string) {
+	m.assertNoForgottenModules("SetOrderMigrations", moduleNames)
+	m.OrderMigrations = moduleNames
+}
+
 // RegisterInvariants registers all module invariants
 func (m *Manager) RegisterInvariants(ir sdk.InvariantRegistry) {
 	for _, module := range m.Modules {
@@ -336,24 +344,29 @@ func (m *Manager) ExportGenesis(ctx sdk.Context, cdc codec.JSONCodec) map[string
 	return genesisData
 }
 
-// checkForgottenModules checks that we didn't forget any modules in the
+// assertNoForgottenModules checks that we didn't forget any modules in the
 // SetOrder* functions.
-func (m *Manager) checkForgottenModules(setOrderFnName string, moduleNames []string) {
-	setOrderMap := map[string]struct{}{}
+func (m *Manager) assertNoForgottenModules(setOrderFnName string, moduleNames []string) {
+	ms := make(map[string]bool)
 	for _, m := range moduleNames {
-		setOrderMap[m] = struct{}{}
+		ms[m] = true
 	}
-
-	if len(setOrderMap) != len(m.Modules) {
-		panic(fmt.Sprintf("got %d modules in the module manager, but %d modules in %s", len(m.Modules), len(setOrderMap), setOrderFnName))
+	var missing []string
+	for m := range m.Modules {
+		if !ms[m] {
+			missing = append(missing, m)
+		}
+	}
+	if len(missing) != 0 {
+		panic(fmt.Sprintf(
+			"%s: all modules must be defined when setting SetOrderMigrations, missing: %v", setOrderFnName, missing))
 	}
 }
 
 // MigrationHandler is the migration function that each module registers.
 type MigrationHandler func(sdk.Context) error
 
-// VersionMap is a map of moduleName -> version, where version denotes the
-// version from which we should perform the migration for each module.
+// VersionMap is a map of moduleName -> version
 type VersionMap map[string]uint64
 
 // RunMigrations performs in-place store migrations for all modules. This
@@ -380,9 +393,8 @@ type VersionMap map[string]uint64
 //      `InitGenesis` on that module.
 // - return the `updatedVM` to be persisted in the x/upgrade's store.
 //
-// Migrations are run in an alphabetical order, except x/auth which is run last. If you want
-// to change the order then you should run migrations in multiple stages as described in
-// docs/core/upgrade.md.
+// Migrations are run in an order defined by `Manager.OrderMigrations` or (if not set) defined by
+// `DefaultMigrationsOrder` function.
 //
 // As an app developer, if you wish to skip running InitGenesis for your new
 // module "foo", you need to manually pass a `fromVM` argument to this function
@@ -410,30 +422,13 @@ func (m Manager) RunMigrations(ctx sdk.Context, cfg Configurator, fromVM Version
 	if !ok {
 		return nil, sdkerrors.Wrapf(sdkerrors.ErrInvalidType, "expected %T, got %T", configurator{}, cfg)
 	}
-
-	updatedVM := make(VersionMap)
-	// for deterministic iteration order
-	// (as some migrations depend on other modules
-	// and the order of executing migrations matters)
-	// TODO: make the order user-configurable?
-	sortedModNames := make([]string, 0, len(m.Modules))
-	hasAuth := false
-	const authModulename = "auth" // using authtypes.ModuleName causes import cycle.
-	for key := range m.Modules {
-		if key != authModulename {
-			sortedModNames = append(sortedModNames, key)
-		} else {
-			hasAuth = true
-		}
-	}
-	sort.Strings(sortedModNames)
-	// auth module must be pushed at the end because it might depend on the state from
-	// other modules, eg x/staking
-	if hasAuth {
-		sortedModNames = append(sortedModNames, authModulename)
+	var modules = m.OrderMigrations
+	if modules == nil {
+		modules = DefaultMigrationsOrder(m.ModuleNames())
 	}
 
-	for _, moduleName := range sortedModNames {
+	updatedVM := VersionMap{}
+	for _, moduleName := range modules {
 		module := m.Modules[moduleName]
 		fromVersion, exists := fromVM[moduleName]
 		toVersion := module.ConsensusVersion()
@@ -526,3 +521,35 @@ func (m *Manager) GetVersionMap() VersionMap {
 
 	return vermap
 }
+
+// ModuleNames returns list of all module names, without any particular order.
+func (m *Manager) ModuleNames() []string {
+	ms := make([]string, len(m.Modules))
+	i := 0
+	for m := range m.Modules {
+		ms[i] = m
+		i++
+	}
+	return ms
+}
+
+// DefaultMigrationsOrder returns a default migrations order: ascending alphabetical by module name,
+// except x/auth which will run last, see:
+// https://github.com/cosmos/cosmos-sdk/issues/10591
+func DefaultMigrationsOrder(modules []string) []string {
+	const authName = "auth"
+	out := make([]string, 0, len(modules))
+	hasAuth := false
+	for _, m := range modules {
+		if m == authName {
+			hasAuth = true
+		} else {
+			out = append(out, m)
+		}
+	}
+	sort.Strings(out)
+	if hasAuth {
+		out = append(out, authName)
+	}
+	return out
+}

types/module/module_int_test.go

@@ -0,0 +1,57 @@
+package module
+
+import (
+	"sort"
+	"testing"
+
+	"github.com/stretchr/testify/suite"
+)
+
+func TestModuleIntSuite(t *testing.T) {
+	suite.Run(t, new(TestSuite))
+}
+
+type TestSuite struct {
+	suite.Suite
+}
+
+func (s TestSuite) TestAssertNoForgottenModules() {
+	m := Manager{
+		Modules: map[string]AppModule{"a": nil, "b": nil},
+	}
+	tcs := []struct {
+		name     string
+		positive bool
+		modules  []string
+	}{
+		{"same modules", true, []string{"a", "b"}},
+		{"more modules", true, []string{"a", "b", "c"}},
+	}
+
+	for _, tc := range tcs {
+		if tc.positive {
+			m.assertNoForgottenModules("x", tc.modules)
+		} else {
+			s.Panics(func() { m.assertNoForgottenModules("x", tc.modules) })
+		}
+	}
+}
+
+func (s TestSuite) TestModuleNames() {
+	m := Manager{
+		Modules: map[string]AppModule{"a": nil, "b": nil},
+	}
+	ms := m.ModuleNames()
+	sort.Strings(ms)
+	s.Require().Equal([]string{"a", "b"}, ms)
+}
+
+func (s TestSuite) TestDefaultMigrationsOrder() {
+	require := s.Require()
+	require.Equal(
+		[]string{"auth2", "d", "z", "auth"},
+		DefaultMigrationsOrder([]string{"d", "auth", "auth2", "z"}), "alphabetical, but auth should be last")
+	require.Equal(
+		[]string{"auth2", "d", "z"},
+		DefaultMigrationsOrder([]string{"d", "auth2", "z"}), "alphabetical")
+}