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 * GraphContext, 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 * GraphContext, 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 * GraphContext, 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 {
// TODO: Make this a select between reading client data and getting updates from the event to push to clients"
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)
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 TypeList []graphql.Type
type ObjTypeMap map[reflect.Type]*graphql.Object
type FieldMap map[string]*graphql.Field
type GQLThread struct {
BaseThread
http_server *http.Server
http_done *sync.WaitGroup
}
type GQLThreadInfo struct {
ThreadInfo
Start bool
Started bool
}
func NewGQLThreadInfo(start bool) GQLThreadInfo {
info := GQLThreadInfo{
Start: start,
Started: false,
}
return info
}
type GQLThreadStateJSON struct {
BaseThreadStateJSON
Listen string
}
type GQLThreadState struct {
BaseThreadState
Listen string
}
func (state * GQLThreadState) MarshalJSON() ([]byte, error) {
thread_state := SaveBaseThreadState(&state.BaseThreadState)
return json.Marshal(&GQLThreadStateJSON{
BaseThreadStateJSON: thread_state,
Listen: state.Listen,
})
}
func LoadGQLThreadState(ctx * GraphContext, data []byte, loaded_nodes NodeMap) (NodeState, error){
var j GQLThreadStateJSON
err := json.Unmarshal(data, &j)
if err != nil {
return nil, err
}
thread_state, err := RestoreBaseThreadState(ctx, j.BaseThreadStateJSON, loaded_nodes)
if err != nil {
return nil, err
}
state := &GQLThreadState{
BaseThreadState: *thread_state,
Listen: j.Listen,
}
return state, nil
}
func LoadGQLThread(ctx * GraphContext, id NodeID) (GraphNode, error) {
thread := RestoreBaseThread(ctx, id)
gql_thread := GQLThread{
BaseThread: thread,
http_server: nil,
http_done: &sync.WaitGroup{},
}
return &gql_thread, nil
}
func NewGQLThreadState(listen string) GQLThreadState {
state := GQLThreadState{
BaseThreadState: NewBaseThreadState("GQL Server", "gql_thread"),
Listen: listen,
}
state.InfoType = reflect.TypeOf((*GQLThreadInfo)(nil))
return state
}
var gql_actions ThreadActions = ThreadActions{
"start": func(ctx * GraphContext, thread Thread) (string, error) {
ctx.Log.Logf("gql", "SERVER_STARTED")
server := thread.(*GQLThread)
// 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, []GraphNode{server}, func(states NodeStateMap)(error){
server_state := states[server.ID()].(*GQLThreadState)
server.http_server = &http.Server{
Addr: server_state.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 * GraphContext, thread Thread, signal GraphSignal) (string, error) {
ctx.Log.Logf("gql", "GQL_THREAD_CHILD_ADDED: %+v", signal)
UseStates(ctx, []GraphNode{thread}, func(states NodeStateMap)(error) {
server_state := states[thread.ID()].(*GQLThreadState)
should_run, exists := server_state.child_info[signal.Source()].(*GQLThreadInfo)
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 && should_run.Started == false {
ChildGo(ctx, server_state, thread, signal.Source())
should_run.Started = false
}
return nil
})
return "wait", nil
},
"abort": func(ctx * GraphContext, 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 "", fmt.Errorf("GQLThread aborted by signal")
},
"cancel": func(ctx * GraphContext, 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 "", nil
},
}
func NewGQLThread(ctx * GraphContext, listen string, requirements []Lockable) (*GQLThread, error) {
state := NewGQLThreadState(listen)
base_thread, err := NewBaseThread(ctx, gql_actions, gql_handlers, &state)
if err != nil {
return nil, err
}
thread := &GQLThread {
BaseThread: base_thread,
http_server: nil,
http_done: &sync.WaitGroup{},
}
err = LinkLockables(ctx, thread, requirements)
if err != nil {
return nil, err
}
return thread, nil
}