Add ChildGo to conveniently start children

gql.go

@@ -321,30 +321,46 @@ type FieldMap map[string]*graphql.Field
 
 type GQLThread struct {
   BaseThread
+  http_server *http.Server
+  http_done *sync.WaitGroup
   extended_types ObjTypeMap
   extended_queries FieldMap
   extended_subscriptions FieldMap
   extended_mutations FieldMap
 }
 
+type GQLThreadInfo struct {
+  ThreadInfo
+  Start bool
+  Started bool
+}
+
+func NewGQLThreadInfo(start bool) GQLThreadInfo {
+  info := GQLThreadInfo{
+    Start: start,
+    Started: false,
+  }
+  return info
+}
+
 type GQLThreadState struct {
   BaseThreadState
   Listen string
 }
 
 func NewGQLThreadState(listen string) GQLThreadState {
-  return GQLThreadState{
+  state := GQLThreadState{
     BaseThreadState: NewBaseThreadState("GQL Server"),
     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)
-    go func() {
-      ctx.Log.Logf("gql", "GOROUTINE_START for %s", server.ID())
 
     mux := http.NewServeMux()
     http_handler, ws_handler := MakeGQLHandlers(ctx, server)
@@ -354,46 +370,60 @@ var gql_actions ThreadActions = ThreadActions{
     fs := http.FileServer(http.Dir("./site"))
     mux.Handle("/site/", http.StripPrefix("/site", fs))
 
-      srv_if, _ := UseStates(ctx, []GraphNode{server}, func(states []NodeState)(interface{}, error){
+    UseStates(ctx, []GraphNode{server}, func(states []NodeState)(interface{}, error){
       server_state := states[0].(*GQLThreadState)
-        return &http.Server{
+      server.http_server = &http.Server{
         Addr: server_state.Listen,
         Handler: mux,
-        }, nil
+      }
+      return nil, nil
     })
-      srv := srv_if.(*http.Server)
 
-      http_done := &sync.WaitGroup{}
-      http_done.Add(1)
-      go func(srv *http.Server, http_done *sync.WaitGroup) {
-        defer http_done.Done()
-        err := srv.ListenAndServe()
+    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))
       }
-      }(srv, http_done)
+    }(server)
 
-      for true {
-        select {
-        case signal:=<-server.signal:
-          if signal.Type() == "abort" || signal.Type() == "cancel" {
-            err := srv.Shutdown(context.Background())
-            if err != nil{
-              panic(fmt.Sprintf("Failed to shutdown gql server: %s", err))
-            }
-            http_done.Wait()
-            break
-          }
-          ctx.Log.Logf("gql", "GOROUTINE_SIGNAL for %s: %+v", server.ID(), signal)
-          // Take signals to resource and send to GQL subscriptions
-        }
-      }
-    }()
     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 []NodeState)(interface{}, error) {
+      server_state := states[0].(*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, nil
+      }
+      if should_run.Start == true && should_run.Started == false {
+        ChildGo(ctx, server_state, thread, signal.Source())
+        should_run.Started = false
+      }
+      return nil, 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, extended_types ObjTypeMap, extended_queries FieldMap, extended_mutations FieldMap, extended_subscriptions FieldMap) (*GQLThread, error) {
@@ -405,6 +435,8 @@ func NewGQLThread(ctx * GraphContext, listen string, requirements []Lockable, ex
 
   thread := &GQLThread {
     BaseThread: base_thread,
+    http_server: nil,
+    http_done: &sync.WaitGroup{},
     extended_types: extended_types,
     extended_queries: extended_queries,
     extended_mutations: extended_mutations,

gql_test.go

@@ -6,18 +6,28 @@ import (
 )
 
 func TestGQLThread(t * testing.T) {
+  println("TEST_GQL")
   ctx := logTestContext(t, []string{"gqlws", "gql", "thread", "update"})
   gql_thread, err := NewGQLThread(ctx, ":8080", []Lockable{}, ObjTypeMap{}, FieldMap{}, FieldMap{}, FieldMap{})
   fatalErr(t, err)
 
-  test_thread, err := NewSimpleBaseThread(ctx, "Test thread 1", []Lockable{}, ThreadActions{}, ThreadHandlers{})
+  test_thread_1, err := NewSimpleBaseThread(ctx, "Test thread 1", []Lockable{}, ThreadActions{}, ThreadHandlers{})
   fatalErr(t, err)
 
-  err = LinkThreads(ctx, gql_thread, test_thread, nil)
+  test_thread_2, err := NewSimpleBaseThread(ctx, "Test thread 2", []Lockable{}, ThreadActions{}, ThreadHandlers{})
+  fatalErr(t, err)
+
+  i1 := NewGQLThreadInfo(true)
+  err = LinkThreads(ctx, gql_thread, test_thread_1, &i1)
+  fatalErr(t, err)
+
+  i2 := NewGQLThreadInfo(false)
+  err = LinkThreads(ctx, gql_thread, test_thread_2, &i2)
   fatalErr(t, err)
 
   go func(thread Thread){
     time.Sleep(10*time.Millisecond)
+    // Check that test_thread_1 is running and test_thread_2 is not
     SendUpdate(ctx, thread, CancelSignal(nil))
   }(gql_thread)
 

thread.go

@@ -3,6 +3,7 @@ package graphvent
 import (
   "fmt"
   "time"
+  "sync"
   "errors"
   "reflect"
   "encoding/json"
@@ -53,8 +54,11 @@ type ThreadState interface {
   Parent() Thread
   SetParent(parent Thread)
   Children() []Thread
+  Child(id NodeID) Thread
   ChildInfo(child NodeID) ThreadInfo
   AddChild(child Thread, info ThreadInfo) error
+  Start() error
+  Stop() error
 }
 
 type BaseThreadState struct {
@@ -63,6 +67,7 @@ type BaseThreadState struct {
   children []Thread
   child_info map[NodeID] ThreadInfo
   InfoType reflect.Type
+  running bool
 }
 
 type BaseThreadStateJSON struct {
@@ -90,6 +95,22 @@ func (state * BaseThreadState) MarshalJSON() ([]byte, error) {
   })
 }
 
+func (state * BaseThreadState) Start() error {
+  if state.running == true {
+    return fmt.Errorf("Cannot start a running thread")
+  }
+  state.running = true
+  return nil
+}
+
+func (state * BaseThreadState) Stop() error {
+  if state.running == false {
+    return fmt.Errorf("Cannot stop a thread that's not running")
+  }
+  state.running = false
+  return nil
+}
+
 func (state * BaseThreadState) Parent() Thread {
   return state.parent
 }
@@ -102,6 +123,17 @@ func (state * BaseThreadState) Children() []Thread {
   return state.children
 }
 
+func (state * BaseThreadState) Child(id NodeID) Thread {
+  for _, child := range(state.children) {
+    if child.ID() == id {
+      return child
+    }
+  }
+  return nil
+}
+
+
+
 func (state * BaseThreadState) ChildInfo(child NodeID) ThreadInfo {
   return state.child_info[child]
 }
@@ -188,6 +220,8 @@ func LinkThreads(ctx * GraphContext, thread Thread, child Thread, info ThreadInf
     return err
   }
 
+  SendUpdate(ctx, thread, NewSignal(child, "child_added"))
+
   return nil
 }
 
@@ -202,6 +236,8 @@ type Thread interface {
   ClearTimeout()
   Timeout() <-chan time.Time
   TimeoutAction() string
+
+  ChildWaits() *sync.WaitGroup
 }
 
 func FindChild(ctx * GraphContext, thread Thread, thread_state ThreadState, id NodeID) Thread {
@@ -228,8 +264,26 @@ func FindChild(ctx * GraphContext, thread Thread, thread_state ThreadState, id N
   return nil
 }
 
+func ChildGo(ctx * GraphContext, thread_state ThreadState, thread Thread, child_id NodeID) {
+  child := thread_state.Child(child_id)
+  if child == nil {
+    panic(fmt.Errorf("Child not in thread, can't start %s", child_id))
+  }
+  thread.ChildWaits().Add(1)
+  go func(child Thread) {
+    ctx.Log.Logf("gql", "THREAD_START_CHILD: %s", child.ID())
+    defer thread.ChildWaits().Done()
+    err := RunThread(ctx, child)
+    if err != nil {
+      ctx.Log.Logf("gql", "THREAD_CHILD_RUN_ERR: %s %e", child.ID(), err)
+    } else {
+      ctx.Log.Logf("gql", "THREAD_CHILD_RUN_DONE: %s", child.ID())
+    }
+  }(child)
+}
+
 func RunThread(ctx * GraphContext, thread Thread) error {
-  ctx.Log.Logf("thread", "EVENT_RUN: %s", thread.ID())
+  ctx.Log.Logf("thread", "THREAD_RUN: %s", thread.ID())
 
   err := LockLockable(ctx, thread, thread, nil)
   if err != nil {
@@ -239,9 +293,11 @@ func RunThread(ctx * GraphContext, thread Thread) error {
   _, err = UseStates(ctx, []GraphNode{thread}, func(states []NodeState) (interface{}, error) {
     thread_state := states[0].(ThreadState)
     if thread_state.Owner() == nil {
-      return nil, fmt.Errorf("EVENT_RUN_NOT_LOCKED: %s", thread_state.Name())
+      return nil, fmt.Errorf("THREAD_RUN_NOT_LOCKED: %s", thread_state.Name())
     } else if thread_state.Owner().ID() != thread.ID() {
-      return nil, fmt.Errorf("EVENT_RUN_RESOURCE_ALREADY_LOCKED: %s, %s", thread_state.Name(), thread_state.Owner().ID())
+      return nil, fmt.Errorf("THREAD_RUN_RESOURCE_ALREADY_LOCKED: %s, %s", thread_state.Name(), thread_state.Owner().ID())
+    } else if err := thread_state.Start(); err != nil {
+      return nil, fmt.Errorf("THREAD_START_ERR: %e", err)
     }
     return nil, nil
   })
@@ -256,16 +312,26 @@ func RunThread(ctx * GraphContext, thread Thread) error {
       return errors.New(error_str)
     }
 
-    ctx.Log.Logf("thread", "EVENT_ACTION: %s - %s", thread.ID(), next_action)
+    ctx.Log.Logf("thread", "THREAD_ACTION: %s - %s", thread.ID(), next_action)
     next_action, err = action(ctx, thread)
     if err != nil {
       return err
     }
   }
 
+  _, err = UseStates(ctx, []GraphNode{thread}, func(states []NodeState) (interface{}, error) {
+    thread_state := states[0].(ThreadState)
+    err := thread_state.Stop()
+    return nil, err
+  })
+  if err != nil {
+    ctx.Log.Logf("thread", "THREAD_RUN_STOP_ERR: %e", err)
+    return err
+  }
+
   SendUpdate(ctx, thread, NewSignal(thread, "thread_done"))
 
-  ctx.Log.Logf("thread", "EVENT_RUN_DONE: %s", thread.ID())
+  ctx.Log.Logf("thread", "THREAD_RUN_DONE: %s", thread.ID())
 
   return nil
 }
@@ -287,6 +353,12 @@ type BaseThread struct {
 
   timeout <-chan time.Time
   timeout_action string
+
+  child_waits sync.WaitGroup
+}
+
+func (thread * BaseThread) ChildWaits() *sync.WaitGroup {
+  return &thread.child_waits
 }
 
 func (thread * BaseThread) Lock(node GraphNode, state LockableState) error {