package graphvent
import (
"net/http"
"github.com/graphql-go/graphql"
"github.com/graphql-go/graphql/language/parser"
"github.com/graphql-go/graphql/language/source"
"github.com/graphql-go/graphql/language/ast"
"context"
"encoding/json"
"io"
"reflect"
"fmt"
"sync"
"github.com/gobwas/ws"
"github.com/gobwas/ws/wsutil"
)
func GraphiQLHandler() func(http.ResponseWriter, *http.Request) {
return func(w http.ResponseWriter, r * http.Request) {
graphiql_string := fmt.Sprintf(`
GraphiQL
Loading...
`)
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.WriteHeader(http.StatusOK)
io.WriteString(w, graphiql_string)
}
}
type GQLWSPayload 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 GQLWSPayload `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", "*")
}
func GQLHandler(ctx * Context, server * GQLThread) func(http.ResponseWriter, *http.Request) {
gql_ctx := context.Background()
gql_ctx = context.WithValue(gql_ctx, "graph_context", ctx)
gql_ctx = context.WithValue(gql_ctx, "gql_server", server)
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
}
ctx.Log.Logm("gql", header_map, "REQUEST_HEADERS")
str, err := io.ReadAll(r.Body)
if err != nil {
ctx.Log.Logf("gql", "failed to read request body: %s", err)
return
}
query := GQLWSPayload{}
json.Unmarshal(str, &query)
params := graphql.Params{
Schema: ctx.GQL.Schema,
Context: gql_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", 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 ""
}
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 ""
}
func GQLWSDo(ctx * Context, p graphql.Params) chan *graphql.Result {
operation := getOperationTypeOfReq(p)
ctx.Log.Logf("gqlws", "GQLWSDO_OPERATION: %s %+v", operation, p.RequestString)
if operation == ast.OperationTypeSubscription {
return graphql.Subscribe(p)
}
res := graphql.Do(p)
return sendOneResultAndClose(res)
}
func GQLWSHandler(ctx * Context, server * GQLThread) func(http.ResponseWriter, *http.Request) {
gql_ctx := context.Background()
gql_ctx = context.WithValue(gql_ctx, "graph_context", ctx)
gql_ctx = context.WithValue(gql_ctx, "gql_server", server)
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
}
ctx.Log.Logm("gql", header_map, "REQUEST_HEADERS")
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
}
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")
}
} else if msg.Type == "subscribe" {
ctx.Log.Logf("gqlws", "SUBSCRIBE: %+v", msg.Payload)
params := graphql.Params{
Schema: ctx.GQL.Schema,
Context: gql_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
}
res_chan := GQLWSDo(ctx, params)
if res_chan == nil {
ctx.Log.Logf("gqlws", "res_chan is nil")
} else {
ctx.Log.Logf("gqlws", "res_chan: %+v", res_chan)
}
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("gqlws", 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: GQLWSPayload{
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 GQLThread struct {
SimpleThread
http_server *http.Server
http_done *sync.WaitGroup
Listen string
}
func (thread * GQLThread) Type() NodeType {
return NodeType("gql_thread")
}
func (thread * GQLThread) Serialize() ([]byte, error) {
thread_json := NewGQLThreadJSON(thread)
return json.MarshalIndent(&thread_json, "", " ")
}
func (thread * GQLThread) DeserializeInfo(ctx *Context, data []byte) (ThreadInfo, error) {
var info ParentThreadInfo
err := json.Unmarshal(data, &info)
if err != nil {
return nil, err
}
return &info, nil
}
type GQLThreadJSON struct {
SimpleThreadJSON
Listen string `json:"listen"`
}
func NewGQLThreadJSON(thread *GQLThread) GQLThreadJSON {
thread_json := NewSimpleThreadJSON(&thread.SimpleThread)
return GQLThreadJSON{
SimpleThreadJSON: thread_json,
Listen: thread.Listen,
}
}
func LoadGQLThread(ctx *Context, id NodeID, data []byte, nodes NodeMap) (Node, error) {
var j GQLThreadJSON
err := json.Unmarshal(data, &j)
if err != nil {
return nil, err
}
thread := NewGQLThread(id, j.Name, j.StateName, j.Listen)
nodes[id] = &thread
err = RestoreSimpleThread(ctx, &thread, j.SimpleThreadJSON, nodes)
if err != nil {
return nil, err
}
return &thread, nil
}
func NewGQLThread(id NodeID, name string, state_name string, listen string) GQLThread {
return GQLThread{
SimpleThread: NewSimpleThread(id, name, state_name, reflect.TypeOf((*ParentThreadInfo)(nil)), gql_actions, gql_handlers),
Listen: listen,
http_done: &sync.WaitGroup{},
}
}
var gql_actions ThreadActions = ThreadActions{
"wait": ThreadWait,
"restore": func(ctx * Context, thread Thread) (string, error) {
// Start all the threads that should be "started"
ctx.Log.Logf("gql", "GQL_THREAD_RESTORE: %s", thread.ID())
ThreadRestore(ctx, thread)
return "start_server", nil
},
"start": func(ctx * Context, thread Thread) (string, error) {
ctx.Log.Logf("gql", "GQL_START")
err := ThreadStart(ctx, thread)
if err != nil {
return "", err
}
return "start_server", nil
},
"start_server": func(ctx * Context, thread Thread) (string, error) {
server, ok := thread.(*GQLThread)
if ok == false {
return "", fmt.Errorf("GQL_THREAD_START: %s is not GQLThread, %+v", thread.ID(), thread.State())
}
ctx.Log.Logf("gql", "GQL_START_SERVER")
// Serve the GQL http and ws handlers
mux := http.NewServeMux()
mux.HandleFunc("/gql", GQLHandler(ctx, server))
mux.HandleFunc("/gqlws", GQLWSHandler(ctx, server))
// Server a graphiql interface(TODO make configurable whether to start this)
mux.HandleFunc("/graphiql", GraphiQLHandler())
// Server the ./site directory to /site (TODO make configurable with better defaults)
fs := http.FileServer(http.Dir("./site"))
mux.Handle("/site/", http.StripPrefix("/site", fs))
UseStates(ctx, []Node{server}, func(nodes NodeMap)(error){
server.http_server = &http.Server{
Addr: server.Listen,
Handler: mux,
}
return nil
})
server.http_done.Add(1)
go func(server *GQLThread) {
defer server.http_done.Done()
err := server.http_server.ListenAndServe()
if err != http.ErrServerClosed {
panic(fmt.Sprintf("Failed to start gql server: %s", err))
}
}(server)
return "wait", nil
},
}
var gql_handlers ThreadHandlers = ThreadHandlers{
"child_added": func(ctx * Context, thread Thread, signal GraphSignal) (string, error) {
ctx.Log.Logf("gql", "GQL_THREAD_CHILD_ADDED: %+v", signal)
UpdateStates(ctx, []Node{thread}, func(nodes NodeMap)(error) {
should_run, exists := thread.ChildInfo(signal.Source()).(*ParentThreadInfo)
if exists == false {
ctx.Log.Logf("gql", "GQL_THREAD_CHILD_ADDED: tried to start %s whis is not a child")
return nil
}
if should_run.Start == true {
ChildGo(ctx, thread, thread.Child(signal.Source()), should_run.StartAction)
}
return nil
})
return "wait", nil
},
"abort": func(ctx * Context, thread Thread, signal GraphSignal) (string, error) {
ctx.Log.Logf("gql", "GQL_ABORT")
server := thread.(*GQLThread)
server.http_server.Shutdown(context.TODO())
server.http_done.Wait()
return ThreadAbort(ctx, thread, signal)
},
"cancel": func(ctx * Context, thread Thread, signal GraphSignal) (string, error) {
ctx.Log.Logf("gql", "GQL_CANCEL")
server := thread.(*GQLThread)
server.http_server.Shutdown(context.TODO())
server.http_done.Wait()
return ThreadCancel(ctx, thread, signal)
},
}