feat: add endblocker with valsetupdate type (#15829)

types/module/module.go

@@ -29,6 +29,7 @@ needlessly defining many placeholder functions
 package module
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -212,6 +213,11 @@ type EndBlockAppModule interface {
 	EndBlock(sdk.Context, abci.RequestEndBlock) []abci.ValidatorUpdate
 }
 
+type HasABCIEndblock interface {
+	AppModule
+	EndBlock(context.Context) ([]abci.ValidatorUpdate, error)
+}
+
 // GenesisOnlyAppModule is an AppModule that only has import/export functionality
 type GenesisOnlyAppModule struct {
 	AppModuleGenesis
@@ -695,6 +701,22 @@ func (m *Manager) EndBlock(ctx sdk.Context, req abci.RequestEndBlock) (abci.Resp
 			if err != nil {
 				return abci.ResponseEndBlock{}, err
 			}
+		} else if module, ok := m.Modules[moduleName].(HasABCIEndblock); ok {
+			moduleValUpdates, err := module.EndBlock(ctx)
+			if err != nil {
+				return abci.ResponseEndBlock{}, err
+			}
+			// use these validator updates if provided, the module manager assumes
+			// only one module will update the validator set
+			if len(moduleValUpdates) > 0 {
+				if len(validatorUpdates) > 0 {
+					return abci.ResponseEndBlock{}, errors.New("validator EndBlock updates already set by a previous module")
+				}
+
+				for _, updates := range moduleValUpdates {
+					validatorUpdates = append(validatorUpdates, abci.ValidatorUpdate{PubKey: updates.PubKey, Power: updates.Power})
+				}
+			}
 		} else {
 			continue
 		}