[MM-52924] Implement ConfigurationWillBeSaved plugin hook (#23567)

* Implement ConfigurationWillBeSaved plugin hook

* Add comment

* Update comment

* Fix potential nil dereference if plugin environment is unset

* Address PR review

server/public/plugin/client_rpc_generated.go

@@ -1037,6 +1037,42 @@ func (s *hooksRPCServer) GetTopicMetadataByIds(args *Z_GetTopicMetadataByIdsArgs
 	return nil
 }
 
+func init() {
+	hookNameToId["ConfigurationWillBeSaved"] = ConfigurationWillBeSavedID
+}
+
+type Z_ConfigurationWillBeSavedArgs struct {
+	A *model.Config
+}
+
+type Z_ConfigurationWillBeSavedReturns struct {
+	A *model.Config
+	B error
+}
+
+func (g *hooksRPCClient) ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error) {
+	_args := &Z_ConfigurationWillBeSavedArgs{newCfg}
+	_returns := &Z_ConfigurationWillBeSavedReturns{}
+	if g.implemented[ConfigurationWillBeSavedID] {
+		if err := g.client.Call("Plugin.ConfigurationWillBeSaved", _args, _returns); err != nil {
+			g.log.Error("RPC call ConfigurationWillBeSaved to plugin failed.", mlog.Err(err))
+		}
+	}
+	return _returns.A, _returns.B
+}
+
+func (s *hooksRPCServer) ConfigurationWillBeSaved(args *Z_ConfigurationWillBeSavedArgs, returns *Z_ConfigurationWillBeSavedReturns) error {
+	if hook, ok := s.impl.(interface {
+		ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error)
+	}); ok {
+		returns.A, returns.B = hook.ConfigurationWillBeSaved(args.A)
+		returns.B = encodableError(returns.B)
+	} else {
+		return encodableError(fmt.Errorf("Hook ConfigurationWillBeSaved called but not implemented."))
+	}
+	return nil
+}
+
 type Z_RegisterCommandArgs struct {
 	A *model.Command
 }

server/public/plugin/hooks.go

@@ -49,6 +49,7 @@ const (
 	GetTopicRedirectID              = 31
 	GetCollectionMetadataByIdsID    = 32
 	GetTopicMetadataByIdsID         = 33
+	ConfigurationWillBeSavedID      = 34
 	TotalHooksID                    = iota
 )
 
@@ -336,4 +337,11 @@ type Hooks interface {
 	//
 	// Minimum server version: 7.6
 	GetTopicMetadataByIds(c *Context, topicType string, topicIds []string) (map[string]*model.TopicMetadata, error)
+
+	// ConfigurationWillBeSaved is invoked before saving the configuration to the
+	// backing store.
+	// An error can be returned to reject the operation. Additionally, a new
+	// config object can be returned to be stored in place of the provided one.
+	// Minimum server version: 8.0
+	ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error)
 }

server/public/plugin/hooks_timer_layer_generated.go

@@ -253,3 +253,10 @@ func (hooks *hooksTimerLayer) GetTopicMetadataByIds(c *Context, topicType string
 	hooks.recordTime(startTime, "GetTopicMetadataByIds", _returnsB == nil)
 	return _returnsA, _returnsB
 }
+
+func (hooks *hooksTimerLayer) ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error) {
+	startTime := timePkg.Now()
+	_returnsA, _returnsB := hooks.hooksImpl.ConfigurationWillBeSaved(newCfg)
+	hooks.recordTime(startTime, "ConfigurationWillBeSaved", _returnsB == nil)
+	return _returnsA, _returnsB
+}

server/public/plugin/plugintest/hooks.go

@@ -25,6 +25,32 @@ func (_m *Hooks) ChannelHasBeenCreated(c *plugin.Context, channel *model.Channel
 	_m.Called(c, channel)
 }
 
+// ConfigurationWillBeSaved provides a mock function with given fields: newCfg
+func (_m *Hooks) ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error) {
+	ret := _m.Called(newCfg)
+
+	var r0 *model.Config
+	var r1 error
+	if rf, ok := ret.Get(0).(func(*model.Config) (*model.Config, error)); ok {
+		return rf(newCfg)
+	}
+	if rf, ok := ret.Get(0).(func(*model.Config) *model.Config); ok {
+		r0 = rf(newCfg)
+	} else {
+		if ret.Get(0) != nil {
+			r0 = ret.Get(0).(*model.Config)
+		}
+	}
+
+	if rf, ok := ret.Get(1).(func(*model.Config) error); ok {
+		r1 = rf(newCfg)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
 // ExecuteCommand provides a mock function with given fields: c, args
 func (_m *Hooks) ExecuteCommand(c *plugin.Context, args *model.CommandArgs) (*model.CommandResponse, *model.AppError) {
 	ret := _m.Called(c, args)

server/public/plugin/product_hooks_generated.go

@@ -138,6 +138,10 @@ type GetTopicMetadataByIdsIFace interface {
 	GetTopicMetadataByIds(c *Context, topicType string, topicIds []string) (map[string]*model.TopicMetadata, error)
 }
 
+type ConfigurationWillBeSavedIFace interface {
+	ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error)
+}
+
 type HooksAdapter struct {
 	implemented  map[int]struct{}
 	productHooks any
@@ -430,6 +434,15 @@ func NewAdapter(productHooks any) (*HooksAdapter, error) {
 		return nil, errors.New("hook has GetTopicMetadataByIds method but does not implement plugin.GetTopicMetadataByIds interface")
 	}
 
+	// Assessing the type of the productHooks if it individually implements ConfigurationWillBeSaved interface.
+	tt = reflect.TypeOf((*ConfigurationWillBeSavedIFace)(nil)).Elem()
+
+	if ft.Implements(tt) {
+		a.implemented[ConfigurationWillBeSavedID] = struct{}{}
+	} else if _, ok := ft.MethodByName("ConfigurationWillBeSaved"); ok {
+		return nil, errors.New("hook has ConfigurationWillBeSaved method but does not implement plugin.ConfigurationWillBeSaved interface")
+	}
+
 	return a, nil
 }
 
@@ -711,3 +724,12 @@ func (a *HooksAdapter) GetTopicMetadataByIds(c *Context, topicType string, topic
 	return a.productHooks.(GetTopicMetadataByIdsIFace).GetTopicMetadataByIds(c, topicType, topicIds)
 
 }
+
+func (a *HooksAdapter) ConfigurationWillBeSaved(newCfg *model.Config) (*model.Config, error) {
+	if _, ok := a.implemented[ConfigurationWillBeSavedID]; !ok {
+		panic("product hooks must implement ConfigurationWillBeSaved")
+	}
+
+	return a.productHooks.(ConfigurationWillBeSavedIFace).ConfigurationWillBeSaved(newCfg)
+
+}