graphvent/gql.go

858 lines
24 KiB
Go

package graphvent
import (
"context"
"crypto/ecdh"
"crypto/ecdsa"
"crypto/elliptic"
"crypto/rand"
"crypto/x509"
"encoding/json"
"fmt"
"io"
"os"
"net"
"net/http"
"reflect"
"sync"
"time"
"github.com/gobwas/ws"
"github.com/gobwas/ws/wsutil"
"github.com/graphql-go/graphql"
"github.com/graphql-go/graphql/language/ast"
"github.com/graphql-go/graphql/language/parser"
"github.com/graphql-go/graphql/language/source"
"crypto/x509/pkix"
"encoding/pem"
"math/big"
"github.com/google/uuid"
)
func PrepResolve(p graphql.ResolveParams) (*ResolveContext, error) {
resolve_context, ok := p.Context.Value("resolve").(*ResolveContext)
if ok == false {
return nil, fmt.Errorf("Bad resolve in params context")
}
return resolve_context, nil
}
// TODO: Make composabe by checking if K is a slice, then recursing in the same way that ExtractList does
func ExtractParam[K interface{}](p graphql.ResolveParams, name string) (K, error) {
var zero K
arg_if, ok := p.Args[name]
if ok == false {
return zero, fmt.Errorf("No Arg of name %s", name)
}
arg, ok := arg_if.(K)
if ok == false {
return zero, fmt.Errorf("Failed to cast arg %s(%+v) to %+v", name, arg_if, reflect.TypeOf(zero))
}
return arg, nil
}
func ExtractList[K interface{}](p graphql.ResolveParams, name string) ([]K, error) {
var zero K
arg_list, err := ExtractParam[[]interface{}](p, name)
if err != nil {
return nil, err
}
ret := make([]K, len(arg_list))
for i, val := range(arg_list) {
val_conv, ok := arg_list[i].(K)
if ok == false {
return nil, fmt.Errorf("Failed to cast arg %s[%d](%+v) to %+v", name, i, val, reflect.TypeOf(zero))
}
ret[i] = val_conv
}
return ret, nil
}
func GraphiQLHandler() func(http.ResponseWriter, *http.Request) {
return func(w http.ResponseWriter, r * http.Request) {
graphiql_string := fmt.Sprintf(`
<!--
* Copyright (c) 2021 GraphQL Contributors
* All rights reserved.
*
* This source code is licensed under the license found in the
* LICENSE file in the root directory of this source tree.
-->
<!DOCTYPE html>
<html lang="en">
<head>
<title>GraphiQL</title>
<style>
body {
height: 100%%;
margin: 0;
width: 100%%;
overflow: hidden;
}
#graphiql {
height: 100vh;
}
</style>
<!--
This GraphiQL example depends on Promise and fetch, which are available in
modern browsers, but can be "polyfilled" for older browsers.
GraphiQL itself depends on React DOM.
If you do not want to rely on a CDN, you can host these files locally or
include them directly in your favored resource bundler.
-->
<script
crossorigin
src="https://unpkg.com/react@18/umd/react.development.js"
></script>
<script
crossorigin
src="https://unpkg.com/react-dom@18/umd/react-dom.development.js"
></script>
<!--
These two files can be found in the npm module, however you may wish to
copy them directly into your environment, or perhaps include them in your
favored resource bundler.
-->
<link rel="stylesheet" href="https://unpkg.com/graphiql/graphiql.min.css" />
</head>
<body>
<div id="graphiql">Loading...</div>
<script
src="https://unpkg.com/graphiql/graphiql.min.js"
type="application/javascript"
></script>
<script>
if (window.authToken === undefined) {
const root = ReactDOM.createRoot(document.getElementById('graphiql'));
root.render(
React.createElement(GraphiQL, {
fetcher: GraphiQL.createFetcher({
url: '/gql',
}),
defaultEditorToolsVisibility: true,
}),
);
} else {
authToken().then(function(res){
const root = ReactDOM.createRoot(document.getElementById('graphiql'));
root.render(
React.createElement(GraphiQL, {
fetcher: GraphiQL.createFetcher({
url: '/gql',
headers: {
"Authorization": ` + "`${res}`" + `,
},
}),
defaultEditorToolsVisibility: true,
}),
);
});
}
</script>
</body>
</html>
`)
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.WriteHeader(http.StatusOK)
io.WriteString(w, graphiql_string)
}
}
type GQLPayload struct {
OperationName string `json:"operationName,omitempty"`
Query string `json:"query,omitempty"`
Variables map[string]interface{} `json:"variables,omitempty"`
Extensions map[string]interface{} `json:"extensions,omitempty"`
Data string `json:"data,omitempty"`
}
type GQLWSMsg struct {
ID string `json:"id,omitempty"`
Type string `json:"type"`
Payload GQLPayload `json:"payload,omitempty"`
}
func enableCORS(w *http.ResponseWriter) {
(*w).Header().Set("Access-Control-Allow-Origin", "*")
(*w).Header().Set("Access-Control-Allow-Credentials", "true")
(*w).Header().Set("Access-Control-Allow-Headers", "*")
(*w).Header().Set("Access-Control-Allow-Methods", "*")
}
type GQLUnauthorized string
func (e GQLUnauthorized) Is(target error) bool {
error_type := reflect.TypeOf(GQLUnauthorized(""))
target_type := reflect.TypeOf(target)
return error_type == target_type
}
func (e GQLUnauthorized) Error() string {
return fmt.Sprintf("GQL_UNAUTHORIZED_ERROR: %s", string(e))
}
func (e GQLUnauthorized) MarshalJSON() ([]byte, error) {
return json.MarshalIndent(&struct{
Error string `json:"error"`
}{
Error: string(e),
}, "", " ")
}
// Context passed to each resolve execution
type ResolveContext struct {
// Resolution ID
ID uuid.UUID
// Channels for the gql extension to route data to this context
Chans map[uuid.UUID]chan Signal
// Graph Context this resolver is running under
Context *Context
// Pointer to the node that's currently processing this request
Server *Node
// The state data for the node processing this request
Ext *GQLExt
// Cache of resolved nodes
NodeCache map[NodeID]NodeResult
}
func NewResolveContext(ctx *Context, server *Node, gql_ext *GQLExt) (*ResolveContext, error) {
return &ResolveContext{
ID: uuid.New(),
Ext: gql_ext,
Chans: map[uuid.UUID]chan Signal{},
Context: ctx,
NodeCache: map[NodeID]NodeResult{},
Server: server,
}, nil
}
func GQLHandler(ctx *Context, server *Node, gql_ext *GQLExt) func(http.ResponseWriter, *http.Request) {
return func(w http.ResponseWriter, r * http.Request) {
ctx.Log.Logf("gql", "GQL REQUEST: %s", r.RemoteAddr)
enableCORS(&w)
header_map := map[string]interface{}{}
for header, value := range(r.Header) {
header_map[header] = value
}
resolve_context, err := NewResolveContext(ctx, server, gql_ext)
if err != nil {
ctx.Log.Logf("gql", "GQL_AUTH_ERR: %s", err)
json.NewEncoder(w).Encode(GQLUnauthorized(""))
return
} else {
ctx.Log.Logf("gql", "New Query: %s", resolve_context.ID)
}
req_ctx := context.Background()
req_ctx = context.WithValue(req_ctx, "resolve", resolve_context)
str, err := io.ReadAll(r.Body)
if err != nil {
ctx.Log.Logf("gql", "GQL_READ_ERR: %s", err)
json.NewEncoder(w).Encode(fmt.Sprintf("%e", err))
return
}
query := GQLPayload{}
json.Unmarshal(str, &query)
schema := ctx.Extensions[ExtTypeFor[GQLExt]()].Data.(graphql.Schema)
params := graphql.Params{
Schema: schema,
Context: req_ctx,
RequestString: query.Query,
}
if query.OperationName != "" {
params.OperationName = query.OperationName
}
if len(query.Variables) > 0 {
params.VariableValues = query.Variables
}
result := graphql.Do(params)
if len(result.Errors) > 0 {
extra_fields := map[string]interface{}{}
extra_fields["body"] = string(str)
extra_fields["headers"] = r.Header
ctx.Log.Logm("gql_errors", extra_fields, "wrong result, unexpected errors: %v", result.Errors)
}
json.NewEncoder(w).Encode(result)
}
}
func sendOneResultAndClose(res *graphql.Result) chan *graphql.Result {
resultChannel := make(chan *graphql.Result)
go func() {
resultChannel <- res
close(resultChannel)
}()
return resultChannel
}
func getOperationTypeOfReq(p graphql.Params) string{
source := source.NewSource(&source.Source{
Body: []byte(p.RequestString),
Name: "GraphQL request",
})
AST, err := parser.Parse(parser.ParseParams{Source: source})
if err != nil {
return err.Error()
}
for _, node := range AST.Definitions {
if operationDef, ok := node.(*ast.OperationDefinition); ok {
name := ""
if operationDef.Name != nil {
name = operationDef.Name.Value
}
if name == p.OperationName || p.OperationName == "" {
return operationDef.Operation
}
}
}
return "END_OF_FUNCTION"
}
func GQLWSHandler(ctx * Context, server *Node, gql_ext *GQLExt) func(http.ResponseWriter, *http.Request) {
return func(w http.ResponseWriter, r * http.Request) {
ctx.Log.Logf("gqlws_new", "HANDLING %s",r.RemoteAddr)
enableCORS(&w)
header_map := map[string]interface{}{}
for header, value := range(r.Header) {
header_map[header] = value
}
resolve_context, err := NewResolveContext(ctx, server, gql_ext)
if err != nil {
ctx.Log.Logf("gql", "GQL_AUTH_ERR: %s", err)
return
} else {
ctx.Log.Logf("gql", "New Subscription: %s", resolve_context.ID)
}
req_ctx := context.Background()
req_ctx = context.WithValue(req_ctx, "resolve", resolve_context)
u := ws.HTTPUpgrader{
Protocol: func(protocol string) bool {
ctx.Log.Logf("gqlws", "UPGRADE_PROTOCOL: %s", string(protocol))
if string(protocol) == "graphql-transport-ws" || string(protocol) == "graphql-ws" {
return true
}
return false
},
}
conn, _, _, err := u.Upgrade(r, w)
if err == nil {
defer conn.Close()
conn_state := "init"
for {
msg_raw, op, err := wsutil.ReadClientData(conn)
ctx.Log.Logf("gqlws_hb", "MSG: %s\nOP: 0x%02x\nERR: %+v\n", string(msg_raw), op, err)
msg := GQLWSMsg{}
json.Unmarshal(msg_raw, &msg)
if err != nil {
ctx.Log.Logf("gqlws", "WS_CLIENT_ERROR")
break
}
if msg.Type == "connection_init" {
if conn_state != "init" {
ctx.Log.Logf("gqlws", "WS_CLIENT_ERROR: INIT WHILE IN %s", conn_state)
break
}
connection_params := struct {
Payload struct {
Token string `json:"token"`
} `json:"payload"`
}{}
err := json.Unmarshal([]byte(msg_raw), &connection_params)
if err != nil {
ctx.Log.Logf("gqlws", "WS_UNMARSHAL_ERROR: %s - %+v", msg_raw, err)
break
}
conn_state = "ready"
err = wsutil.WriteServerMessage(conn, 1, []byte("{\"type\": \"connection_ack\"}"))
if err != nil {
ctx.Log.Logf("gqlws", "WS_SERVER_ERROR: FAILED TO SEND connection_ack")
break
}
} else if msg.Type == "ping" {
ctx.Log.Logf("gqlws_hb", "PING FROM %s", r.RemoteAddr)
err = wsutil.WriteServerMessage(conn, 1, []byte("{\"type\": \"pong\"}"))
if err != nil {
ctx.Log.Logf("gqlws", "WS_SERVER_ERROR: FAILED TO SEND PONG")
break
}
} else if msg.Type == "subscribe" {
ctx.Log.Logf("gqlws", "SUBSCRIBE: %+v", msg.Payload)
schema := ctx.Extensions[ExtTypeFor[GQLExt]()].Data.(graphql.Schema)
params := graphql.Params{
Schema: schema,
Context: req_ctx,
RequestString: msg.Payload.Query,
}
if msg.Payload.OperationName != "" {
params.OperationName = msg.Payload.OperationName
}
if len(msg.Payload.Variables) > 0 {
params.VariableValues = msg.Payload.Variables
}
var res_chan chan *graphql.Result
operation := getOperationTypeOfReq(params)
if operation == ast.OperationTypeSubscription {
res_chan = graphql.Subscribe(params)
} else {
res := graphql.Do(params)
res_chan = sendOneResultAndClose(res)
}
go func(res_chan chan *graphql.Result) {
for {
next, ok := <-res_chan
if ok == false {
ctx.Log.Logf("gqlws", "response channel was closed")
return
}
if next == nil {
ctx.Log.Logf("gqlws", "NIL_ON_CHANNEL")
return
}
if len(next.Errors) > 0 {
extra_fields := map[string]interface{}{}
extra_fields["query"] = string(msg.Payload.Query)
ctx.Log.Logm("gql_errors", extra_fields, "ERROR: wrong result, unexpected errors: %+v", next.Errors)
continue
}
ctx.Log.Logf("gqlws", "DATA: %+v", next.Data)
data, err := json.Marshal(next.Data)
if err != nil {
ctx.Log.Logf("gqlws", "ERROR: %+v", err)
continue
}
msg, err := json.Marshal(GQLWSMsg{
ID: msg.ID,
Type: "next",
Payload: GQLPayload{
Data: string(data),
},
})
if err != nil {
ctx.Log.Logf("gqlws", "ERROR: %+v", err)
continue
}
err = wsutil.WriteServerMessage(conn, 1, msg)
if err != nil {
ctx.Log.Logf("gqlws", "ERROR: %+v", err)
continue
}
}
}(res_chan)
} else {
}
}
return
} else {
panic("Failed to upgrade websocket")
}
}
}
type Interface struct {
Interface *graphql.Interface
Default *graphql.Object
List *graphql.List
Extensions []ExtType
}
type Type struct {
Type *graphql.Object
List *graphql.List
}
type Field struct {
Ext ExtType
Name string
Field *graphql.Field
}
type NodeResult struct {
NodeID NodeID
NodeType NodeType
Data map[string]interface{}
}
type ListField struct {
ACLName string
Extension ExtType
ResolveFn func(graphql.ResolveParams, *ResolveContext, reflect.Value) ([]NodeID, error)
}
type SelfField struct {
ACLName string
Extension ExtType
ResolveFn func(graphql.ResolveParams, *ResolveContext, reflect.Value) (*NodeID, error)
}
type SubscriptionInfo struct {
ID uuid.UUID
NodeCache *map[NodeID]NodeResult
Channel chan interface{}
}
type GQLExt struct {
tcp_listener net.Listener
http_server *http.Server
http_done sync.WaitGroup
subscriptions []SubscriptionInfo
subscriptions_lock sync.RWMutex
// map of read request IDs to response channels
resolver_response map[uuid.UUID]chan Signal
resolver_response_lock sync.RWMutex
State string `gv:"state"`
TLSKey []byte `gv:"tls_key"`
TLSCert []byte `gv:"tls_cert"`
Listen string `gv:"listen" gql:"GQLListen"`
}
func (ext *GQLExt) Load(ctx *Context, node *Node) error {
ctx.Log.Logf("gql", "Loading GQL server extension on %s", node.ID)
return ext.StartGQLServer(ctx, node)
}
func (ext *GQLExt) Unload(ctx *Context, node *Node) {
ctx.Log.Logf("gql", "Unloading GQL server extension on %s", node.ID)
err := ext.StopGQLServer()
if err != nil {
ctx.Log.Logf("gql", "Error unloading GQL server extension on %s: %s", node.ID, err)
} else {
ctx.Log.Logf("gql", "Unloaded GQL server extension on %s", node.ID)
}
}
func (ext *GQLExt) PostDeserialize(*Context) error {
ext.resolver_response = map[uuid.UUID]chan Signal{}
ext.subscriptions = []SubscriptionInfo{}
return nil
}
func (ext *GQLExt) AddSubscription(id uuid.UUID, ctx *ResolveContext) (chan interface{}, error) {
ext.subscriptions_lock.Lock()
defer ext.subscriptions_lock.Unlock()
for _, info := range(ext.subscriptions) {
if info.ID == id {
return nil, fmt.Errorf("%+v already in subscription list", info.ID)
}
}
c := make(chan interface{}, 100)
ext.subscriptions = append(ext.subscriptions, SubscriptionInfo{
id,
&ctx.NodeCache,
c,
})
return c, nil
}
func (ext *GQLExt) RemoveSubscription(id uuid.UUID) error {
ext.subscriptions_lock.Lock()
defer ext.subscriptions_lock.Unlock()
for i, info := range(ext.subscriptions) {
if info.ID == id {
ext.subscriptions[i] = ext.subscriptions[len(ext.subscriptions)]
ext.subscriptions = ext.subscriptions[:len(ext.subscriptions)-1]
return nil
}
}
return fmt.Errorf("%+v not in subscription list", id)
}
func (ext *GQLExt) FindResponseChannel(req_id uuid.UUID) chan Signal {
ext.resolver_response_lock.RLock()
response_chan, _ := ext.resolver_response[req_id]
ext.resolver_response_lock.RUnlock()
return response_chan
}
func (ext *GQLExt) GetResponseChannel(req_id uuid.UUID) chan Signal {
response_chan := make(chan Signal, 1)
ext.resolver_response_lock.Lock()
ext.resolver_response[req_id] = response_chan
ext.resolver_response_lock.Unlock()
return response_chan
}
func (ext *GQLExt) FreeResponseChannel(req_id uuid.UUID) chan Signal {
response_chan := ext.FindResponseChannel(req_id)
if response_chan != nil {
ext.resolver_response_lock.Lock()
delete(ext.resolver_response, req_id)
ext.resolver_response_lock.Unlock()
}
return response_chan
}
func (ext *GQLExt) Process(ctx *Context, node *Node, source NodeID, signal Signal) ([]SendMsg, Changes) {
// Process ReadResultSignalType by forwarding it to the waiting resolver
var changes Changes = nil
var messages []SendMsg = nil
switch sig := signal.(type) {
case *SuccessSignal:
response_chan := ext.FreeResponseChannel(sig.ReqID)
if response_chan != nil {
select {
case response_chan <- sig:
ctx.Log.Logf("gql", "Forwarded success to resolver, %+v", sig.ReqID)
default:
ctx.Log.Logf("gql", "Resolver channel overflow %+v", sig)
}
}
case *ErrorSignal:
// TODO: Forward to resolver if waiting for it
response_chan := ext.FreeResponseChannel(sig.ReqID)
if response_chan != nil {
select {
case response_chan <- sig:
ctx.Log.Logf("gql", "Forwarded error to resolver, %+v", sig.Error)
default:
ctx.Log.Logf("gql", "Resolver channel overflow %+v", sig)
}
}
case *ReadResultSignal:
response_chan := ext.FindResponseChannel(sig.ReqID)
if response_chan != nil {
select {
case response_chan <- sig:
default:
ctx.Log.Logf("gql", "Resolver channel overflow %+v", sig)
}
}
case *StatusSignal:
ext.subscriptions_lock.RLock()
for _, sub := range(ext.subscriptions) {
_, cached := (*sub.NodeCache)[sig.Source]
if cached {
select {
case sub.Channel <- sig:
ctx.Log.Logf("gql", "forwarded status signal %+v to subscription: %s", sig, sub.ID)
default:
ctx.Log.Logf("gql", "subscription channel overflow: %s", sub.ID)
}
}
}
ext.subscriptions_lock.RUnlock()
}
return messages, changes
}
var ecdsa_curves = map[uint8]elliptic.Curve{
0: elliptic.P256(),
}
var ecdsa_curve_ids = map[elliptic.Curve]uint8{
elliptic.P256(): 0,
}
var ecdh_curves = map[uint8]ecdh.Curve{
0: ecdh.P256(),
}
var ecdh_curve_ids = map[ecdh.Curve]uint8{
ecdh.P256(): 0,
}
func NewGQLExt(ctx *Context, listen string, tls_cert []byte, tls_key []byte) (*GQLExt, error) {
if tls_cert == nil || tls_key == nil {
ssl_key, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
if err != nil {
return nil, err
}
ssl_key_bytes, err := x509.MarshalPKCS8PrivateKey(ssl_key)
if err != nil {
return nil, err
}
ssl_key_pem := pem.EncodeToMemory(&pem.Block{Type: "PRIVATE KEY", Bytes: ssl_key_bytes})
serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
serialNumber, _ := rand.Int(rand.Reader, serialNumberLimit)
notBefore := time.Now()
notAfter := notBefore.Add(365*24*time.Hour)
template := x509.Certificate{
SerialNumber: serialNumber,
Subject: pkix.Name{
Organization: []string{"mekkanized"},
},
NotBefore: notBefore,
NotAfter: notAfter,
KeyUsage: x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
BasicConstraintsValid: true,
}
ssl_cert, err := x509.CreateCertificate(rand.Reader, &template, &template, ssl_key.Public(), ssl_key)
if err != nil {
return nil, err
}
ssl_cert_pem := pem.EncodeToMemory(&pem.Block{Type: "CERTIFICATE", Bytes: ssl_cert})
tls_cert = ssl_cert_pem
tls_key = ssl_key_pem
}
return &GQLExt{
Listen: listen,
resolver_response: map[uuid.UUID]chan Signal{},
subscriptions: []SubscriptionInfo{},
TLSCert: tls_cert,
TLSKey: tls_key,
}, nil
}
// Returns "${base}/${path}" if it's a file or "${base}/${path}/index.html" if it's a directory
// Returns os.ErrInvalid if "${base}/${path}/index.html" is a directory
func getContentPath(base string, path string) (string, error) {
full_path := fmt.Sprintf("%s%s", base, path)
path_info, err := os.Stat(full_path)
if err != nil && err != os.ErrNotExist {
return "", err
} else if path_info.IsDir() == true {
index_path := ""
if path[len(path)-1] != '/' {
index_path = fmt.Sprintf("%s%s/index.html", base, path)
} else {
index_path = fmt.Sprintf("%s%sindex.html", base, path)
}
index_info, err := os.Stat(index_path)
if err != nil {
return "", err
} else if index_info.IsDir() == true {
return index_path, os.ErrInvalid
} else {
return index_path, nil
}
} else {
return full_path, nil
}
}
func (ext *GQLExt) StartGQLServer(ctx *Context, node *Node) error {
if ext.tcp_listener != nil || ext.http_server != nil {
return fmt.Errorf("listener or server is still running, stop them first")
}
mux := http.NewServeMux()
mux.HandleFunc("/gql", GQLHandler(ctx, node, ext))
mux.HandleFunc("/gqlws", GQLWSHandler(ctx, node, ext))
mux.HandleFunc("/graphiql", GraphiQLHandler())
// Server the ./site directory to /site (TODO make configurable with better defaults)
mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request){
custom_path, err_1 := getContentPath("./custom", r.URL.Path)
if err_1 != nil {
static_path, err_2 := getContentPath("./site", r.URL.Path)
if err_2 != nil {
ctx.Log.Logf("gql", "File Resolve errors: %s - %s", err_1, err_2)
w.WriteHeader(501)
w.Write([]byte("{\"error\": \"server_error\"}"))
} else {
ctx.Log.Logf("gql", "STATIC_FILE: %s", static_path)
file, err := os.Open(static_path)
if err != nil {
w.WriteHeader(501)
w.Write([]byte("{\"error\": \"server_error\"}"))
}
http.ServeContent(w, r, static_path, time.Time{}, file)
}
} else {
ctx.Log.Logf("gql", "CUSTOM_FILE: %s", custom_path)
file, err := os.Open(custom_path)
if err != nil {
w.WriteHeader(501)
w.Write([]byte("{\"error\": \"server_error\"}"))
}
http.ServeContent(w, r, custom_path, time.Time{}, file)
w.WriteHeader(200)
}
})
http_server := &http.Server{
Addr: ext.Listen,
Handler: mux,
}
l, err := net.Listen("tcp", http_server.Addr)
if err != nil {
return fmt.Errorf("Failed to start listener for server on %s", http_server.Addr)
}
ext.http_done.Add(1)
go func(qql_ext *GQLExt) {
defer ext.http_done.Done()
err := http_server.Serve(l)
if err != http.ErrServerClosed {
panic(fmt.Sprintf("Failed to start gql server: %s", err))
}
}(ext)
ext.tcp_listener = l
ext.http_server = http_server
ext.State = "running"
return nil
}
func (ext *GQLExt) StopGQLServer() error {
if ext.tcp_listener == nil || ext.http_server == nil {
return fmt.Errorf("already shutdown, cannot shut down again" )
}
ext.http_server.Shutdown(context.TODO())
ext.http_done.Wait()
ext.tcp_listener = nil
ext.http_server = nil
ext.State = "stopped"
return nil
}