mattermost/server/public/plugin/client_rpc.go

// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.

//go:generate go run interface_generator/main.go

package plugin

import (
	"bytes"
	"database/sql"
	"database/sql/driver"
	"encoding/gob"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"net/rpc"
	"net/url"
	"os"
	"reflect"
	"sync"

	"github.com/hashicorp/go-plugin"
	"github.com/lib/pq"

	"github.com/mattermost/mattermost/server/public/model"
	"github.com/mattermost/mattermost/server/public/shared/mlog"
)

// Plugin RPC Architecture
//
// Mattermost plugins run as separate OS processes for isolation and safety, using
// HashiCorp's go-plugin library. Communication between the server and plugins is
// bidirectional via RPC:
//
//	┌─────────────────────────┐                    ┌─────────────────────────┐
//	│   Mattermost Server     │                    │     Plugin Process      │
//	│                         │                    │                         │
//	│  ┌───────────────────┐  │   hooks (calls)    │  ┌───────────────────┐  │
//	│  │ hooksRPCClient    │──┼───────────────────►│  │ hooksRPCServer    │  │
//	│  └───────────────────┘  │                    │  └───────────────────┘  │
//	│                         │                    │                         │
//	│  ┌───────────────────┐  │   API (callbacks)  │  ┌───────────────────┐  │
//	│  │ apiRPCServer      │◄─┼────────────────────┼──│ apiRPCClient      │  │
//	│  └───────────────────┘  │                    │  └───────────────────┘  │
//	└─────────────────────────┘                    └─────────────────────────┘
//
// - Server → Plugin (Hooks): hooksRPCClient serializes hook calls and sends them
//   to hooksRPCServer in the plugin process, which delegates to the plugin implementation.
//
// - Plugin → Server (API): apiRPCClient in the plugin serializes API calls and sends
//   them to apiRPCServer in the server, which delegates to the Mattermost API.
//
// The MuxBroker enables multiplexed streaming connections over a single RPC connection,
// which is essential for efficiently streaming HTTP bodies, file uploads, and other
// large data transfers without buffering everything in memory.

var hookNameToId = make(map[string]int)

// hooksRPCClient is the client-side RPC proxy that runs in the Mattermost server process and connects to to the [hooksRPCServer] on the plugin side.
// It implements the Hooks interface and forwards hook invocations to plugins running in
// separate processes via RPC.
//
// When Mattermost needs to call a plugin hook (e.g., MessageWillBePosted), it calls the
// corresponding method on hooksRPCClient, which serializes the arguments and makes an
// RPC call to the plugin process where hooksRPCServer receives and handles it.
//
// The struct also holds references to the API and Driver implementations that will be
// exposed to the plugin via apiRPCServer when the plugin is activated.
type hooksRPCClient struct {
	client      *rpc.Client
	log         *mlog.Logger
	muxBroker   *plugin.MuxBroker
	apiImpl     API
	driver      Driver
	implemented [TotalHooksID]bool
	doneWg      sync.WaitGroup
}

// hooksRPCServer is the server-side RPC handler that runs in the plugin process and receives requests from [hooksRPCClient].
// It receives hook invocations from hooksRPCClient (in the Mattermost server) and
// delegates them to the actual plugin implementation.
//
// During plugin activation (OnActivate), it establishes a reverse RPC connection
// back to the server, creating an apiRPCClient that the plugin uses to call
// Mattermost APIs.
type hooksRPCServer struct {
	impl         any
	muxBroker    *plugin.MuxBroker
	apiRPCClient *apiRPCClient
}

// Implements hashicorp/go-plugin/plugin.Plugin interface to connect the hooks of a plugin
type hooksPlugin struct {
	hooks      any
	apiImpl    API
	driverImpl Driver
	log        *mlog.Logger
}

func (p *hooksPlugin) Server(b *plugin.MuxBroker) (any, error) {
	return &hooksRPCServer{impl: p.hooks, muxBroker: b}, nil
}

func (p *hooksPlugin) Client(b *plugin.MuxBroker, client *rpc.Client) (any, error) {
	return &hooksRPCClient{
		client:    client,
		log:       p.log,
		muxBroker: b,
		apiImpl:   p.apiImpl,
		driver:    p.driverImpl,
	}, nil
}

// apiRPCClient is the client-side RPC proxy that runs in the plugin process and connects to the [apiRPCServer] on the Mattermost server side.
// It implements the API interface and allows plugins to call Mattermost server
// APIs (e.g., GetUser, CreatePost) by forwarding requests via RPC to apiRPCServer.
//
// This is created during plugin activation and injected into the plugin via SetAPI().
type apiRPCClient struct {
	client    *rpc.Client
	muxBroker *plugin.MuxBroker
}

// apiRPCServer is the server-side RPC handler that runs in the Mattermost server process and receives requests from [apiRPCClient].
// It receives API calls from plugins (via apiRPCClient) and delegates them to the actual
// Mattermost API implementation.
//
// This enables plugins to interact with Mattermost functionality like users, posts,
// channels, and configuration through a well-defined API boundary.
type apiRPCServer struct {
	impl      API
	muxBroker *plugin.MuxBroker
}

// ErrorString is a fallback for sending unregistered implementations of the error interface across
// rpc. For example, the errorString type from the github.com/pkg/errors package cannot be
// registered since it is not exported, but this precludes common error handling paradigms.
// ErrorString merely preserves the string description of the error, while satisfying the error
// interface itself to allow other registered types (such as model.AppError) to be sent unmodified.
type ErrorString struct {
	Code int // Code to map to various error variables
	Err  string
}

func (e ErrorString) Error() string {
	return e.Err
}

func encodableError(err error) error {
	if err == nil {
		return nil
	}
	if _, ok := err.(*model.AppError); ok {
		return err
	}

	if _, ok := err.(*pq.Error); ok {
		return err
	}

	ret := &ErrorString{
		Err: err.Error(),
	}

	switch err {
	case io.EOF:
		ret.Code = 1
	case sql.ErrNoRows:
		ret.Code = 2
	case sql.ErrConnDone:
		ret.Code = 3
	case sql.ErrTxDone:
		ret.Code = 4
	case driver.ErrSkip:
		ret.Code = 5
	case driver.ErrBadConn:
		ret.Code = 6
	case driver.ErrRemoveArgument:
		ret.Code = 7
	}

	return ret
}

func decodableError(err error) error {
	if encErr, ok := err.(*ErrorString); ok {
		switch encErr.Code {
		case 1:
			return io.EOF
		case 2:
			return sql.ErrNoRows
		case 3:
			return sql.ErrConnDone
		case 4:
			return sql.ErrTxDone
		case 5:
			return driver.ErrSkip
		case 6:
			return driver.ErrBadConn
		case 7:
			return driver.ErrRemoveArgument
		}
	}
	return err
}

// Registering some types used by MM for encoding/gob used by rpc
func init() {
	gob.Register([]*model.SlackAttachment{})
	gob.Register([]any{})
	gob.Register(map[string]any{})
	gob.Register(&model.AppError{})
	gob.Register(&pq.Error{})
	gob.Register(&ErrorString{})
	gob.Register(&model.AutocompleteDynamicListArg{})
	gob.Register(&model.AutocompleteStaticListArg{})
	gob.Register(&model.AutocompleteTextArg{})
	gob.Register(&model.PreviewPost{})
	gob.Register(model.PropertyOptions[*model.PluginPropertyOption]{})
}

// These enforce compile time checks to make sure types implement the interface
// If you are getting an error here, you probably need to run `make pluginapi` to
// autogenerate RPC glue code
var (
	_ plugin.Plugin = &hooksPlugin{}
	_ Hooks         = &hooksRPCClient{}
)

//
// Below are special cases for hooks or APIs that can not be auto generated
//

func (g *hooksRPCClient) Implemented() (impl []string, err error) {
	err = g.client.Call("Plugin.Implemented", struct{}{}, &impl)
	for _, hookName := range impl {
		if hookId, ok := hookNameToId[hookName]; ok {
			g.implemented[hookId] = true
		}
	}
	return
}

// Implemented replies with the names of the hooks that are implemented.
func (s *hooksRPCServer) Implemented(args struct{}, reply *[]string) error {
	ifaceType := reflect.TypeFor[Hooks]()
	implType := reflect.TypeOf(s.impl)
	selfType := reflect.TypeFor[*hooksRPCServer]()
	var methods []string
	for i := 0; i < ifaceType.NumMethod(); i++ {
		method := ifaceType.Method(i)
		m, ok := implType.MethodByName(method.Name)
		if !ok {
			continue
		} else if m.Type.NumIn() != method.Type.NumIn()+1 {
			continue
		} else if m.Type.NumOut() != method.Type.NumOut() {
			continue
		}
		match := true
		for j := 0; j < method.Type.NumIn(); j++ {
			if m.Type.In(j+1) != method.Type.In(j) {
				match = false
				break
			}
		}
		for j := 0; j < method.Type.NumOut(); j++ {
			if m.Type.Out(j) != method.Type.Out(j) {
				match = false
				break
			}
		}
		if !match {
			continue
		}
		if _, ok := selfType.MethodByName(method.Name); !ok {
			continue
		}
		methods = append(methods, method.Name)
	}
	*reply = methods
	return encodableError(nil)
}

type Z_OnActivateArgs struct {
	APIMuxId    uint32
	DriverMuxId uint32
}

type Z_OnActivateReturns struct {
	A error
}

func (g *hooksRPCClient) OnActivate() error {
	muxId := g.muxBroker.NextId()
	g.doneWg.Add(1)
	go func() {
		defer g.doneWg.Done()
		g.muxBroker.AcceptAndServe(muxId, &apiRPCServer{
			impl:      g.apiImpl,
			muxBroker: g.muxBroker,
		})
	}()

	nextID := g.muxBroker.NextId()
	g.doneWg.Add(1)
	go func() {
		defer g.doneWg.Done()
		g.muxBroker.AcceptAndServe(nextID, &dbRPCServer{
			dbImpl: g.driver,
		})
	}()

	_args := &Z_OnActivateArgs{
		APIMuxId:    muxId,
		DriverMuxId: nextID,
	}
	_returns := &Z_OnActivateReturns{}

	if err := g.client.Call("Plugin.OnActivate", _args, _returns); err != nil {
		g.log.Error("RPC call to OnActivate plugin failed.", mlog.Err(err))
	}
	return _returns.A
}

func (s *hooksRPCServer) OnActivate(args *Z_OnActivateArgs, returns *Z_OnActivateReturns) error {
	connection, err := s.muxBroker.Dial(args.APIMuxId)
	if err != nil {
		return err
	}

	conn2, err := s.muxBroker.Dial(args.DriverMuxId)
	if err != nil {
		return err
	}

	s.apiRPCClient = &apiRPCClient{
		client:    rpc.NewClient(connection),
		muxBroker: s.muxBroker,
	}

	dbClient := &dbRPCClient{
		client: rpc.NewClient(conn2),
	}

	if mmplugin, ok := s.impl.(interface {
		SetAPI(api API)
		SetDriver(driver Driver)
	}); ok {
		mmplugin.SetAPI(s.apiRPCClient)
		mmplugin.SetDriver(dbClient)
	}

	if mmplugin, ok := s.impl.(interface {
		OnConfigurationChange() error
	}); ok {
		if err := mmplugin.OnConfigurationChange(); err != nil {
			fmt.Fprintf(os.Stderr, "[ERROR] call to OnConfigurationChange failed, error: %v", err.Error())
		}
	}

	// Capture output of standard logger because go-plugin
	// redirects it.
	log.SetOutput(os.Stderr)

	if hook, ok := s.impl.(interface {
		OnActivate() error
	}); ok {
		returns.A = encodableError(hook.OnActivate())
	}
	return nil
}

type Z_LoadPluginConfigurationArgsArgs struct{}

type Z_LoadPluginConfigurationArgsReturns struct {
	A []byte
}

func (g *apiRPCClient) LoadPluginConfiguration(dest any) error {
	_args := &Z_LoadPluginConfigurationArgsArgs{}
	_returns := &Z_LoadPluginConfigurationArgsReturns{}
	if err := g.client.Call("Plugin.LoadPluginConfiguration", _args, _returns); err != nil {
		log.Printf("RPC call to LoadPluginConfiguration API failed: %s", err.Error())
	}
	if err := json.Unmarshal(_returns.A, dest); err != nil {
		log.Printf("LoadPluginConfiguration API failed to unmarshal: %s", err.Error())
	}
	return nil
}

func (s *apiRPCServer) LoadPluginConfiguration(args *Z_LoadPluginConfigurationArgsArgs, returns *Z_LoadPluginConfigurationArgsReturns) error {
	var config any
	if hook, ok := s.impl.(interface {
		LoadPluginConfiguration(dest any) error
	}); ok {
		if err := hook.LoadPluginConfiguration(&config); err != nil {
			return err
		}
	}
	b, err := json.Marshal(config)
	if err != nil {
		return err
	}
	returns.A = b
	return nil
}

func init() {
	hookNameToId["ServeHTTP"] = ServeHTTPID
}

// Using a subset of http.Request prevents a known incompatibility when decoding Go v1.23+ gob-encoded x509.Certificate
// structs from Go v1.22 compiled plugins. These come from http.Request.TLS field (*tls.ConnectionState).
type HTTPRequestSubset struct {
	Method     string
	URL        *url.URL
	Proto      string
	ProtoMajor int
	ProtoMinor int
	Header     http.Header
	Host       string
	RemoteAddr string
	RequestURI string
	Body       io.ReadCloser
}

func (r *HTTPRequestSubset) GetHTTPRequest() *http.Request {
	return &http.Request{
		Method:     r.Method,
		URL:        r.URL,
		Proto:      r.Proto,
		ProtoMajor: r.ProtoMajor,
		ProtoMinor: r.ProtoMinor,
		Header:     r.Header,
		Host:       r.Host,
		RemoteAddr: r.RemoteAddr,
		RequestURI: r.RequestURI,
		Body:       r.Body,
	}
}

type Z_ServeHTTPArgs struct {
	ResponseWriterStream uint32
	Request              *HTTPRequestSubset
	Context              *Context
	RequestBodyStream    uint32
}

func (g *hooksRPCClient) ServeHTTP(c *Context, w http.ResponseWriter, r *http.Request) {
	if !g.implemented[ServeHTTPID] {
		http.NotFound(w, r)
		return
	}

	serveHTTPStreamId := g.muxBroker.NextId()
	go func() {
		connection, err := g.muxBroker.Accept(serveHTTPStreamId)
		if err != nil {
			g.log.Error("Plugin failed to ServeHTTP, muxBroker couldn't accept connection", mlog.Uint("serve_http_stream_id", serveHTTPStreamId), mlog.Err(err))
			return
		}
		defer connection.Close()

		rpcServer := rpc.NewServer()
		if err := rpcServer.RegisterName("Plugin", &httpResponseWriterRPCServer{w: w, log: g.log}); err != nil {
			g.log.Error("Plugin failed to ServeHTTP, couldn't register RPC name", mlog.Err(err))
			return
		}
		rpcServer.ServeConn(connection)
	}()

	requestBodyStreamId := uint32(0)
	if r.Body != nil {
		requestBodyStreamId = g.muxBroker.NextId()
		go func() {
			bodyConnection, err := g.muxBroker.Accept(requestBodyStreamId)
			if err != nil {
				g.log.Error("Plugin failed to ServeHTTP, muxBroker couldn't Accept request body connection", mlog.Err(err))
				return
			}
			defer bodyConnection.Close()
			serveIOReader(r.Body, bodyConnection)
		}()
	}

	forwardedRequest := &HTTPRequestSubset{
		Method:     r.Method,
		URL:        r.URL,
		Proto:      r.Proto,
		ProtoMajor: r.ProtoMajor,
		ProtoMinor: r.ProtoMinor,
		Header:     r.Header,
		Host:       r.Host,
		RemoteAddr: r.RemoteAddr,
		RequestURI: r.RequestURI,
	}

	if err := g.client.Call("Plugin.ServeHTTP", Z_ServeHTTPArgs{
		Context:              c,
		ResponseWriterStream: serveHTTPStreamId,
		Request:              forwardedRequest,
		RequestBodyStream:    requestBodyStreamId,
	}, nil); err != nil {
		g.log.Error("Plugin failed to ServeHTTP, RPC call failed", mlog.Err(err))
		http.Error(w, "500 internal server error", http.StatusInternalServerError)
	}
}

func (s *hooksRPCServer) ServeHTTP(args *Z_ServeHTTPArgs, returns *struct{}) error {
	connection, err := s.muxBroker.Dial(args.ResponseWriterStream)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote response writer stream, error: %v", err.Error())
		return err
	}
	w := connectHTTPResponseWriter(connection)
	defer w.Close()

	r := args.Request
	if args.RequestBodyStream != 0 {
		connection, err := s.muxBroker.Dial(args.RequestBodyStream)
		if err != nil {
			fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote request body stream, error: %v", err.Error())
			return err
		}
		r.Body = connectIOReader(connection)
	} else {
		r.Body = io.NopCloser(&bytes.Buffer{})
	}
	defer r.Body.Close()

	httpReq := r.GetHTTPRequest()

	if hook, ok := s.impl.(interface {
		ServeHTTP(c *Context, w http.ResponseWriter, r *http.Request)
	}); ok {
		hook.ServeHTTP(args.Context, w, httpReq)
	} else {
		http.NotFound(w, httpReq)
	}

	return nil
}

// PluginHTTPStream - Streaming version of PluginHTTP that uses MuxBroker for streaming request/response bodies.
// This avoids buffering large payloads in memory.

// Legacy buffered structs (kept for backward compatibility with old servers)
type Z_PluginHTTPArgs struct {
	Request     *HTTPRequestSubset
	RequestBody []byte
}

type Z_PluginHTTPReturns struct {
	Response     *http.Response
	ResponseBody []byte
}

// New streaming structs
type Z_PluginHTTPStreamArgs struct {
	ResponseBodyStream uint32
	Request            *HTTPRequestSubset
	RequestBodyStream  uint32
}

type Z_PluginHTTPStreamReturns struct {
	StatusCode int
	Header     http.Header
}

func (g *apiRPCClient) PluginHTTP(request *http.Request) *http.Response {
	// Try to use the streaming version first (if server supports it)
	// Fall back to buffered version if not available (signaled by nil)
	response, err := g.pluginHTTPStream(request)
	if err != nil {
		// If we error for some other reason other than stream not being
		// implemented just report and fail
		log.Print(err.Error())
		return nil
	}
	if response != nil {
		return response
	}

	// Fallback to buffered version
	return g.pluginHTTPBuffered(request)
}

// pluginHTTPStream attempts to use the new streaming endpoint
func (g *apiRPCClient) pluginHTTPStream(request *http.Request) (*http.Response, error) {
	// Set up request body stream
	requestBodyStreamId := uint32(0)
	if request.Body != nil {
		requestBodyStreamId = g.muxBroker.NextId()
		go func() {
			bodyConnection, err := g.muxBroker.Accept(requestBodyStreamId)
			if err != nil {
				log.Printf("Plugin failed to accept request body connection for PluginHTTPStream: %s", err.Error())
				return
			}
			defer bodyConnection.Close()
			serveIOReader(request.Body, bodyConnection)
		}()
	}

	// Set up response body stream
	responseBodyStreamId := g.muxBroker.NextId()
	responsePipe := make(chan io.ReadCloser, 1)

	go func() {
		connection, err := g.muxBroker.Accept(responseBodyStreamId)
		if err != nil {
			log.Printf("Plugin failed to accept response body connection for PluginHTTPStream: %s", err.Error())
			responsePipe <- nil
			return
		}
		// Don't close connection here - it will be closed when response body is read
		responsePipe <- connectIOReader(connection)
	}()

	forwardedRequest := &HTTPRequestSubset{
		Method:     request.Method,
		URL:        request.URL,
		Proto:      request.Proto,
		ProtoMajor: request.ProtoMajor,
		ProtoMinor: request.ProtoMinor,
		Header:     request.Header,
		Host:       request.Host,
		RemoteAddr: request.RemoteAddr,
		RequestURI: request.RequestURI,
	}

	_args := &Z_PluginHTTPStreamArgs{
		ResponseBodyStream: responseBodyStreamId,
		Request:            forwardedRequest,
		RequestBodyStream:  requestBodyStreamId,
	}

	_returns := &Z_PluginHTTPStreamReturns{}
	if err := g.client.Call("Plugin.PluginHTTPStream", _args, _returns); err != nil {
		// If the method doesn't exist, return nil to trigger fallback
		if err.Error() == "rpc: can't find method Plugin.PluginHTTPStream" {
			return nil, nil
		}
		return nil, fmt.Errorf("RPC call to PluginHTTPStream API failed: %w", err)
	}

	// Wait for response body reader
	responseBody := <-responsePipe
	if responseBody == nil {
		return nil, fmt.Errorf("Failed to get response body stream for PluginHTTPStream")
	}

	// Create response with streamed body
	response := &http.Response{
		StatusCode: _returns.StatusCode,
		Header:     _returns.Header,
		Body:       responseBody,
		Proto:      request.Proto,
		ProtoMajor: request.ProtoMajor,
		ProtoMinor: request.ProtoMinor,
	}

	return response, nil
}

// pluginHTTPBuffered is the original buffered implementation
func (g *apiRPCClient) pluginHTTPBuffered(request *http.Request) *http.Response {
	forwardedRequest := &HTTPRequestSubset{
		Method:     request.Method,
		URL:        request.URL,
		Proto:      request.Proto,
		ProtoMajor: request.ProtoMajor,
		ProtoMinor: request.ProtoMinor,
		Header:     request.Header,
		Host:       request.Host,
		RemoteAddr: request.RemoteAddr,
		RequestURI: request.RequestURI,
	}

	_args := &Z_PluginHTTPArgs{
		Request: forwardedRequest,
	}

	if request.Body != nil {
		requestBody, err := io.ReadAll(request.Body)
		if err != nil {
			log.Printf("RPC call to PluginHTTP API failed: %s", err.Error())
			return nil
		}
		request.Body.Close()
		request.Body = nil

		_args.RequestBody = requestBody
	}

	_returns := &Z_PluginHTTPReturns{}
	if err := g.client.Call("Plugin.PluginHTTP", _args, _returns); err != nil {
		log.Printf("RPC call to PluginHTTP API failed: %s", err.Error())
		return nil
	}

	_returns.Response.Body = io.NopCloser(bytes.NewBuffer(_returns.ResponseBody))

	return _returns.Response
}

func (s *apiRPCServer) PluginHTTPStream(args *Z_PluginHTTPStreamArgs, returns *Z_PluginHTTPStreamReturns) error {
	responseConnection, err := s.muxBroker.Dial(args.ResponseBodyStream)
	if err != nil {
		return encodableError(fmt.Errorf("can't connect to remote response body stream: %w", err))
	}

	// Connect to request body stream
	r := args.Request
	if args.RequestBodyStream != 0 {
		requestConnection, err := s.muxBroker.Dial(args.RequestBodyStream)
		if err != nil {
			return encodableError(fmt.Errorf("can't connect to remote request body stream: %w", err))
		}
		r.Body = connectIOReader(requestConnection)
	} else {
		r.Body = io.NopCloser(&bytes.Buffer{})
	}

	httpReq := r.GetHTTPRequest()

	// Call the PluginHTTP implementation
	if hook, ok := s.impl.(interface {
		PluginHTTP(request *http.Request) *http.Response
	}); ok {
		response := hook.PluginHTTP(httpReq)
		if response != nil {
			returns.StatusCode = response.StatusCode
			returns.Header = response.Header

			// Connect to response body stream and stream the response body
			go func() {
				defer r.Body.Close()
				if response.Body != nil {
					// Stream the response body through the connection
					if _, err := io.Copy(responseConnection, response.Body); err != nil {
						log.Printf("error streaming response body: %s", err.Error())
					}
					response.Body.Close()
				}
				responseConnection.Close()
			}()
		} else {
			r.Body.Close()
		}
	} else {
		r.Body.Close()
		return encodableError(fmt.Errorf("API PluginHTTP called but not implemented"))
	}

	return nil
}

// Server-side handler for old buffered PluginHTTP (for backward compatibility)
func (s *apiRPCServer) PluginHTTP(args *Z_PluginHTTPArgs, returns *Z_PluginHTTPReturns) error {
	args.Request.Body = io.NopCloser(bytes.NewBuffer(args.RequestBody))

	if hook, ok := s.impl.(interface {
		PluginHTTP(request *http.Request) *http.Response
	}); ok {
		response := hook.PluginHTTP(args.Request.GetHTTPRequest())

		responseBody, err := io.ReadAll(response.Body)
		if err != nil {
			return encodableError(fmt.Errorf("RPC call to PluginHTTP API failed: %s", err.Error()))
		}
		response.Body.Close()
		response.Body = nil

		returns.Response = response
		returns.ResponseBody = responseBody
	} else {
		return encodableError(fmt.Errorf("API PluginHTTP called but not implemented"))
	}
	return nil
}

func init() {
	hookNameToId["FileWillBeUploaded"] = FileWillBeUploadedID
}

type Z_FileWillBeUploadedArgs struct {
	A                     *Context
	B                     *model.FileInfo
	UploadedFileStream    uint32
	ReplacementFileStream uint32
}

type Z_FileWillBeUploadedReturns struct {
	A *model.FileInfo
	B string
}

func (g *hooksRPCClient) FileWillBeUploaded(c *Context, info *model.FileInfo, file io.Reader, output io.Writer) (*model.FileInfo, string) {
	if !g.implemented[FileWillBeUploadedID] {
		return info, ""
	}

	uploadedFileStreamId := g.muxBroker.NextId()
	go func() {
		uploadedFileConnection, err := g.muxBroker.Accept(uploadedFileStreamId)
		if err != nil {
			g.log.Error("Plugin failed to serve upload file stream. MuxBroker could not Accept connection", mlog.Err(err))
			return
		}
		defer uploadedFileConnection.Close()
		serveIOReader(file, uploadedFileConnection)
	}()

	replacementDone := make(chan bool)
	replacementFileStreamId := g.muxBroker.NextId()
	go func() {
		defer close(replacementDone)

		replacementFileConnection, err := g.muxBroker.Accept(replacementFileStreamId)
		if err != nil {
			g.log.Error("Plugin failed to serve replacement file stream. MuxBroker could not Accept connection", mlog.Err(err))
			return
		}
		defer replacementFileConnection.Close()
		if _, err := io.Copy(output, replacementFileConnection); err != nil {
			g.log.Error("Error reading replacement file.", mlog.Err(err))
		}
	}()

	_args := &Z_FileWillBeUploadedArgs{c, info, uploadedFileStreamId, replacementFileStreamId}
	_returns := &Z_FileWillBeUploadedReturns{A: _args.B}
	if err := g.client.Call("Plugin.FileWillBeUploaded", _args, _returns); err != nil {
		g.log.Error("RPC call FileWillBeUploaded to plugin failed.", mlog.Err(err))
	}

	// Ensure the io.Copy from the replacementFileConnection above completes.
	<-replacementDone

	return _returns.A, _returns.B
}

func (s *hooksRPCServer) FileWillBeUploaded(args *Z_FileWillBeUploadedArgs, returns *Z_FileWillBeUploadedReturns) error {
	uploadFileConnection, err := s.muxBroker.Dial(args.UploadedFileStream)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote upload file stream, error: %v", err.Error())
		return err
	}
	defer uploadFileConnection.Close()
	fileReader := connectIOReader(uploadFileConnection)
	defer fileReader.Close()

	replacementFileConnection, err := s.muxBroker.Dial(args.ReplacementFileStream)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote replacement file stream, error: %v", err.Error())
		return err
	}
	defer replacementFileConnection.Close()
	returnFileWriter := replacementFileConnection

	if hook, ok := s.impl.(interface {
		FileWillBeUploaded(c *Context, info *model.FileInfo, file io.Reader, output io.Writer) (*model.FileInfo, string)
	}); ok {
		returns.A, returns.B = hook.FileWillBeUploaded(args.A, args.B, fileReader, returnFileWriter)
	} else {
		return fmt.Errorf("hook FileWillBeUploaded called but not implemented")
	}
	return nil
}

// MessageWillBePosted is in this file because of the difficulty of identifying which fields need special behaviour.
// The special behaviour needed is decoding the returned post into the original one to avoid the unintentional removal
// of fields by older plugins.
func init() {
	hookNameToId["MessageWillBePosted"] = MessageWillBePostedID
}

type Z_MessageWillBePostedArgs struct {
	A *Context
	B *model.Post
}

type Z_MessageWillBePostedReturns struct {
	A *model.Post
	B string
}

func (g *hooksRPCClient) MessageWillBePosted(c *Context, post *model.Post) (*model.Post, string) {
	_args := &Z_MessageWillBePostedArgs{c, post}
	_returns := &Z_MessageWillBePostedReturns{A: _args.B}
	if g.implemented[MessageWillBePostedID] {
		if err := g.client.Call("Plugin.MessageWillBePosted", _args, _returns); err != nil {
			g.log.Error("RPC call MessageWillBePosted to plugin failed.", mlog.Err(err))
		}
	}
	return _returns.A, _returns.B
}

func (s *hooksRPCServer) MessageWillBePosted(args *Z_MessageWillBePostedArgs, returns *Z_MessageWillBePostedReturns) error {
	if hook, ok := s.impl.(interface {
		MessageWillBePosted(c *Context, post *model.Post) (*model.Post, string)
	}); ok {
		returns.A, returns.B = hook.MessageWillBePosted(args.A, args.B)
	} else {
		return encodableError(fmt.Errorf("hook MessageWillBePosted called but not implemented"))
	}
	return nil
}

// MessageWillBeUpdated is in this file because of the difficulty of identifying which fields need special behaviour.
// The special behaviour needed is decoding the returned post into the original one to avoid the unintentional removal
// of fields by older plugins.
func init() {
	hookNameToId["MessageWillBeUpdated"] = MessageWillBeUpdatedID
}

type Z_MessageWillBeUpdatedArgs struct {
	A *Context
	B *model.Post
	C *model.Post
}

type Z_MessageWillBeUpdatedReturns struct {
	A *model.Post
	B string
}

func (g *hooksRPCClient) MessageWillBeUpdated(c *Context, newPost, oldPost *model.Post) (*model.Post, string) {
	_args := &Z_MessageWillBeUpdatedArgs{c, newPost, oldPost}
	_default_returns := &Z_MessageWillBeUpdatedReturns{A: _args.B}
	if g.implemented[MessageWillBeUpdatedID] {
		_returns := &Z_MessageWillBeUpdatedReturns{}
		if err := g.client.Call("Plugin.MessageWillBeUpdated", _args, _returns); err != nil {
			g.log.Error("RPC call MessageWillBeUpdated to plugin failed.", mlog.Err(err))
			return _default_returns.A, _default_returns.B
		}
		return _returns.A, _returns.B
	}
	return _default_returns.A, _default_returns.B
}

func (s *hooksRPCServer) MessageWillBeUpdated(args *Z_MessageWillBeUpdatedArgs, returns *Z_MessageWillBeUpdatedReturns) error {
	if hook, ok := s.impl.(interface {
		MessageWillBeUpdated(c *Context, newPost, oldPost *model.Post) (*model.Post, string)
	}); ok {
		returns.A, returns.B = hook.MessageWillBeUpdated(args.A, args.B, args.C)
	} else {
		return encodableError(fmt.Errorf("hook MessageWillBeUpdated called but not implemented"))
	}
	return nil
}

// MessagesWillBeConsumed is in this file because of the difficulty of identifying which fields need special behaviour.
// The special behaviour needed is decoding the returned post into the original one to avoid the unintentional removal
// of fields by older plugins.
func init() {
	hookNameToId["MessagesWillBeConsumed"] = MessagesWillBeConsumedID
}

type Z_MessagesWillBeConsumedArgs struct {
	A []*model.Post
}

type Z_MessagesWillBeConsumedReturns struct {
	A []*model.Post
}

func (g *hooksRPCClient) MessagesWillBeConsumed(posts []*model.Post) []*model.Post {
	_args := &Z_MessagesWillBeConsumedArgs{posts}
	_returns := &Z_MessagesWillBeConsumedReturns{}
	if g.implemented[MessagesWillBeConsumedID] {
		if err := g.client.Call("Plugin.MessagesWillBeConsumed", _args, _returns); err != nil {
			g.log.Error("RPC call MessagesWillBeConsumed to plugin failed.", mlog.Err(err))
		}
	}
	return _returns.A
}

func (s *hooksRPCServer) MessagesWillBeConsumed(args *Z_MessagesWillBeConsumedArgs, returns *Z_MessagesWillBeConsumedReturns) error {
	if hook, ok := s.impl.(interface {
		MessagesWillBeConsumed(posts []*model.Post) []*model.Post
	}); ok {
		returns.A = hook.MessagesWillBeConsumed(args.A)
	} else {
		return encodableError(fmt.Errorf("hook MessagesWillBeConsumed called but not implemented"))
	}
	return nil
}

type Z_LogDebugArgs struct {
	A string
	B []any
}

type Z_LogDebugReturns struct{}

func (g *apiRPCClient) LogDebug(msg string, keyValuePairs ...any) {
	stringifiedPairs := stringifyToObjects(keyValuePairs)
	_args := &Z_LogDebugArgs{msg, stringifiedPairs}
	_returns := &Z_LogDebugReturns{}
	if err := g.client.Call("Plugin.LogDebug", _args, _returns); err != nil {
		log.Printf("RPC call to LogDebug API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogDebug(args *Z_LogDebugArgs, returns *Z_LogDebugReturns) error {
	if hook, ok := s.impl.(interface {
		LogDebug(msg string, keyValuePairs ...any)
	}); ok {
		hook.LogDebug(args.A, args.B...)
	} else {
		return encodableError(fmt.Errorf("API LogDebug called but not implemented"))
	}
	return nil
}

type Z_LogInfoArgs struct {
	A string
	B []any
}

type Z_LogInfoReturns struct{}

func (g *apiRPCClient) LogInfo(msg string, keyValuePairs ...any) {
	stringifiedPairs := stringifyToObjects(keyValuePairs)
	_args := &Z_LogInfoArgs{msg, stringifiedPairs}
	_returns := &Z_LogInfoReturns{}
	if err := g.client.Call("Plugin.LogInfo", _args, _returns); err != nil {
		log.Printf("RPC call to LogInfo API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogInfo(args *Z_LogInfoArgs, returns *Z_LogInfoReturns) error {
	if hook, ok := s.impl.(interface {
		LogInfo(msg string, keyValuePairs ...any)
	}); ok {
		hook.LogInfo(args.A, args.B...)
	} else {
		return encodableError(fmt.Errorf("API LogInfo called but not implemented"))
	}
	return nil
}

type Z_LogWarnArgs struct {
	A string
	B []any
}

type Z_LogWarnReturns struct{}

func (g *apiRPCClient) LogWarn(msg string, keyValuePairs ...any) {
	stringifiedPairs := stringifyToObjects(keyValuePairs)
	_args := &Z_LogWarnArgs{msg, stringifiedPairs}
	_returns := &Z_LogWarnReturns{}
	if err := g.client.Call("Plugin.LogWarn", _args, _returns); err != nil {
		log.Printf("RPC call to LogWarn API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogWarn(args *Z_LogWarnArgs, returns *Z_LogWarnReturns) error {
	if hook, ok := s.impl.(interface {
		LogWarn(msg string, keyValuePairs ...any)
	}); ok {
		hook.LogWarn(args.A, args.B...)
	} else {
		return encodableError(fmt.Errorf("API LogWarn called but not implemented"))
	}
	return nil
}

type Z_LogErrorArgs struct {
	A string
	B []any
}

type Z_LogErrorReturns struct{}

func (g *apiRPCClient) LogError(msg string, keyValuePairs ...any) {
	stringifiedPairs := stringifyToObjects(keyValuePairs)
	_args := &Z_LogErrorArgs{msg, stringifiedPairs}
	_returns := &Z_LogErrorReturns{}
	if err := g.client.Call("Plugin.LogError", _args, _returns); err != nil {
		log.Printf("RPC call to LogError API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogError(args *Z_LogErrorArgs, returns *Z_LogErrorReturns) error {
	if hook, ok := s.impl.(interface {
		LogError(msg string, keyValuePairs ...any)
	}); ok {
		hook.LogError(args.A, args.B...)
	} else {
		return encodableError(fmt.Errorf("API LogError called but not implemented"))
	}
	return nil
}

type Z_LogAuditRecArgs struct {
	A *model.AuditRecord
}

type Z_LogAuditRecReturns struct {
}

// Custom audit logging methods with gob safety checks
func (g *apiRPCClient) LogAuditRec(rec *model.AuditRecord) {
	gobSafeRec := makeAuditRecordGobSafe(*rec)
	_args := &Z_LogAuditRecArgs{&gobSafeRec}
	_returns := &Z_LogAuditRecReturns{}
	if err := g.client.Call("Plugin.LogAuditRec", _args, _returns); err != nil {
		log.Printf("RPC call to LogAuditRec API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogAuditRec(args *Z_LogAuditRecArgs, returns *Z_LogAuditRecReturns) error {
	if hook, ok := s.impl.(interface {
		LogAuditRec(rec *model.AuditRecord)
	}); ok {
		hook.LogAuditRec(args.A)
	} else {
		return encodableError(fmt.Errorf("API LogAuditRec called but not implemented"))
	}
	return nil
}

type Z_LogAuditRecWithLevelArgs struct {
	A *model.AuditRecord
	B mlog.Level
}

type Z_LogAuditRecWithLevelReturns struct {
}

func (g *apiRPCClient) LogAuditRecWithLevel(rec *model.AuditRecord, level mlog.Level) {
	gobSafeRec := makeAuditRecordGobSafe(*rec)
	_args := &Z_LogAuditRecWithLevelArgs{&gobSafeRec, level}
	_returns := &Z_LogAuditRecWithLevelReturns{}
	if err := g.client.Call("Plugin.LogAuditRecWithLevel", _args, _returns); err != nil {
		log.Printf("RPC call to LogAuditRecWithLevel API failed: %s", err.Error())
	}
}

func (s *apiRPCServer) LogAuditRecWithLevel(args *Z_LogAuditRecWithLevelArgs, returns *Z_LogAuditRecWithLevelReturns) error {
	if hook, ok := s.impl.(interface {
		LogAuditRecWithLevel(rec *model.AuditRecord, level mlog.Level)
	}); ok {
		hook.LogAuditRecWithLevel(args.A, args.B)
	} else {
		return encodableError(fmt.Errorf("API LogAuditRecWithLevel called but not implemented"))
	}
	return nil
}

type Z_InstallPluginArgs struct {
	PluginStreamID uint32
	B              bool
}

type Z_InstallPluginReturns struct {
	A *model.Manifest
	B *model.AppError
}

func (g *apiRPCClient) InstallPlugin(file io.Reader, replace bool) (*model.Manifest, *model.AppError) {
	pluginStreamID := g.muxBroker.NextId()

	go func() {
		uploadPluginConnection, err := g.muxBroker.Accept(pluginStreamID)
		if err != nil {
			log.Print("Plugin failed to upload plugin. MuxBroker could not Accept connection", mlog.Err(err))
			return
		}
		defer uploadPluginConnection.Close()
		serveIOReader(file, uploadPluginConnection)
	}()

	_args := &Z_InstallPluginArgs{pluginStreamID, replace}
	_returns := &Z_InstallPluginReturns{}
	if err := g.client.Call("Plugin.InstallPlugin", _args, _returns); err != nil {
		log.Print("RPC call InstallPlugin to plugin failed.", mlog.Err(err))
	}

	return _returns.A, _returns.B
}

func (s *apiRPCServer) InstallPlugin(args *Z_InstallPluginArgs, returns *Z_InstallPluginReturns) error {
	hook, ok := s.impl.(interface {
		InstallPlugin(file io.Reader, replace bool) (*model.Manifest, *model.AppError)
	})
	if !ok {
		return encodableError(fmt.Errorf("API InstallPlugin called but not implemented"))
	}

	receivePluginConnection, err := s.muxBroker.Dial(args.PluginStreamID)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote plugin stream, error: %v", err.Error())
		return err
	}
	pluginReader := connectIOReader(receivePluginConnection)
	defer pluginReader.Close()

	returns.A, returns.B = hook.InstallPlugin(pluginReader, args.B)
	return nil
}

type Z_UploadDataArgs struct {
	A              *model.UploadSession
	PluginStreamID uint32
}

type Z_UploadDataReturns struct {
	A *model.FileInfo
	B error
}

func (g *apiRPCClient) UploadData(us *model.UploadSession, rd io.Reader) (*model.FileInfo, error) {
	pluginStreamID := g.muxBroker.NextId()

	go func() {
		pluginConnection, err := g.muxBroker.Accept(pluginStreamID)
		if err != nil {
			log.Print("Failed to upload data. MuxBroker could not Accept connection", mlog.Err(err))
			return
		}
		defer pluginConnection.Close()
		serveIOReader(rd, pluginConnection)
	}()

	_args := &Z_UploadDataArgs{us, pluginStreamID}
	_returns := &Z_UploadDataReturns{}
	if err := g.client.Call("Plugin.UploadData", _args, _returns); err != nil {
		log.Print("RPC call UploadData to plugin failed.", mlog.Err(err))
	}

	return _returns.A, _returns.B
}

func (s *apiRPCServer) UploadData(args *Z_UploadDataArgs, returns *Z_UploadDataReturns) error {
	hook, ok := s.impl.(interface {
		UploadData(us *model.UploadSession, rd io.Reader) (*model.FileInfo, error)
	})
	if !ok {
		return encodableError(fmt.Errorf("API UploadData called but not implemented"))
	}

	receivePluginConnection, err := s.muxBroker.Dial(args.PluginStreamID)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote plugin stream, error: %v", err.Error())
		return err
	}
	pluginReader := connectIOReader(receivePluginConnection)
	defer pluginReader.Close()

	returns.A, returns.B = hook.UploadData(args.A, pluginReader)
	return nil
}

func init() {
	hookNameToId["ServeMetrics"] = ServeMetricsID
}

type Z_ServeMetricsArgs struct {
	ResponseWriterStream uint32
	Request              *HTTPRequestSubset
	Context              *Context
	RequestBodyStream    uint32
}

func (g *hooksRPCClient) ServeMetrics(c *Context, w http.ResponseWriter, r *http.Request) {
	if !g.implemented[ServeMetricsID] {
		http.NotFound(w, r)
		return
	}

	serveMetricsStreamId := g.muxBroker.NextId()
	go func() {
		connection, err := g.muxBroker.Accept(serveMetricsStreamId)
		if err != nil {
			g.log.Error("Plugin failed to ServeMetrics, muxBroker couldn't accept connection", mlog.Uint("serve_http_stream_id", serveMetricsStreamId), mlog.Err(err))
			return
		}
		defer connection.Close()

		rpcServer := rpc.NewServer()
		if err := rpcServer.RegisterName("Plugin", &httpResponseWriterRPCServer{w: w, log: g.log}); err != nil {
			g.log.Error("Plugin failed to ServeMetrics, couldn't register RPC name", mlog.Err(err))
			return
		}
		rpcServer.ServeConn(connection)
	}()

	requestBodyStreamId := uint32(0)
	if r.Body != nil {
		requestBodyStreamId = g.muxBroker.NextId()
		go func() {
			bodyConnection, err := g.muxBroker.Accept(requestBodyStreamId)
			if err != nil {
				g.log.Error("Plugin failed to ServeMetrics, muxBroker couldn't Accept request body connection", mlog.Err(err))
				return
			}
			defer bodyConnection.Close()
			serveIOReader(r.Body, bodyConnection)
		}()
	}

	forwardedRequest := &HTTPRequestSubset{
		Method:     r.Method,
		URL:        r.URL,
		Proto:      r.Proto,
		ProtoMajor: r.ProtoMajor,
		ProtoMinor: r.ProtoMinor,
		Header:     r.Header,
		Host:       r.Host,
		RemoteAddr: r.RemoteAddr,
		RequestURI: r.RequestURI,
	}

	if err := g.client.Call("Plugin.ServeMetrics", Z_ServeMetricsArgs{
		Context:              c,
		ResponseWriterStream: serveMetricsStreamId,
		Request:              forwardedRequest,
		RequestBodyStream:    requestBodyStreamId,
	}, nil); err != nil {
		g.log.Error("Plugin failed to ServeMetrics, RPC call failed", mlog.Err(err))
		http.Error(w, "500 internal server error", http.StatusInternalServerError)
	}
}

func (s *hooksRPCServer) ServeMetrics(args *Z_ServeMetricsArgs, returns *struct{}) error {
	connection, err := s.muxBroker.Dial(args.ResponseWriterStream)
	if err != nil {
		fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote response writer stream, error: %v", err.Error())
		return err
	}
	w := connectHTTPResponseWriter(connection)
	defer w.Close()

	r := args.Request
	if args.RequestBodyStream != 0 {
		connection, err := s.muxBroker.Dial(args.RequestBodyStream)
		if err != nil {
			fmt.Fprintf(os.Stderr, "[ERROR] Can't connect to remote request body stream, error: %v", err.Error())
			return err
		}
		r.Body = connectIOReader(connection)
	} else {
		r.Body = io.NopCloser(&bytes.Buffer{})
	}
	defer r.Body.Close()

	httpReq := r.GetHTTPRequest()

	if hook, ok := s.impl.(interface {
		ServeMetrics(c *Context, w http.ResponseWriter, r *http.Request)
	}); ok {
		hook.ServeMetrics(args.Context, w, httpReq)
	} else {
		http.NotFound(w, httpReq)
	}

	return nil
}