Moved UUID field to all signals to nodes can wait for responses to specific signals

gql.go

@@ -169,7 +169,7 @@ type ResolveContext struct {
   ID uuid.UUID
 
   // Channel for the gql extension to route data to this context
-  Chan chan *ReadResultSignal
+  Chan chan Signal
 
   // Graph Context this resolver is running under
   Context *Context
@@ -203,7 +203,7 @@ func NewResolveContext(ctx *Context, server *Node, gql_ext *GQLExt, r *http.Requ
   return &ResolveContext{
     Ext: gql_ext,
     ID: uuid.New(),
-    Chan: make(chan *ReadResultSignal, GQL_RESOLVER_CHAN_SIZE),
+    Chan: make(chan Signal, GQL_RESOLVER_CHAN_SIZE),
     Context: ctx,
     GQLContext: ctx.Extensions[Hash(GQLExtType)].Data.(*GQLExtContext),
     Server: server,
@@ -984,10 +984,10 @@ type GQLExt struct {
   http_done sync.WaitGroup `json:"-"`
 
   // map of read request IDs to gql request ID
-  resolver_reads map[uuid.UUID]uuid.UUID `json:"-"`
-  resolver_reads_lock sync.RWMutex `json:"-"`
+  resolver_response map[uuid.UUID]uuid.UUID `json:"-"`
+  resolver_response_lock sync.RWMutex `json:"-"`
   // map of gql request ID to active channel
-  resolver_chans map[uuid.UUID]chan *ReadResultSignal `json:"-"`
+  resolver_chans map[uuid.UUID]chan Signal `json:"-"`
   resolver_chans_lock sync.RWMutex `json:"-"`
 
   State string `json:"state"`
@@ -1006,16 +1006,47 @@ func (ext *GQLExt) Field(name string) interface{} {
 
 func (ext *GQLExt) Process(ctx *Context, source NodeID, node *Node, signal Signal) {
   // Process ReadResultSignalType by forwarding it to the waiting resolver
-  if signal.Type() == ReadResultSignalType {
+  if signal.Type() == ErrorSignalType {
+    // TODO: Forward to resolver if waiting for it
+    sig := signal.(ErrorSignal)
+    ext.resolver_response_lock.RLock()
+    resolver_id, exists := ext.resolver_response[sig.UUID]
+    ext.resolver_response_lock.RUnlock()
+    if exists == true {
+      ext.resolver_response_lock.Lock()
+      delete(ext.resolver_response, sig.UUID)
+      ext.resolver_response_lock.Unlock()
+
+      ext.resolver_chans_lock.RLock()
+      resolver_chan, exists := ext.resolver_chans[resolver_id]
+      ext.resolver_chans_lock.RUnlock()
+      if exists == true {
+        select {
+        case resolver_chan <- sig:
+          ctx.Log.Logf("gql", "Forwarded error to resolver %s, %+v", resolver_id, sig)
+        default:
+          ctx.Log.Logf("gql", "Resolver %s channel overflow %+v", resolver_id, sig)
+          ext.resolver_chans_lock.Lock()
+          delete(ext.resolver_chans, resolver_id)
+          ext.resolver_chans_lock.Unlock()
+        }
+      } else {
+        ctx.Log.Logf("gql", "received error signal response for resolver %s which doesn't exist", resolver_id)
+      }
+
+    } else {
+      ctx.Log.Logf("gql", "received error signal response %s with no mapped resolver", sig.UUID)
+    }
+  } else if signal.Type() == ReadResultSignalType {
     sig := signal.(ReadResultSignal)
-    ext.resolver_reads_lock.RLock()
-    resolver_id, exists := ext.resolver_reads[sig.UUID]
-    ext.resolver_reads_lock.RUnlock()
+    ext.resolver_response_lock.RLock()
+    resolver_id, exists := ext.resolver_response[sig.UUID]
+    ext.resolver_response_lock.RUnlock()
 
     if exists == true {
-      ext.resolver_reads_lock.Lock()
-      delete(ext.resolver_reads, sig.UUID)
-      ext.resolver_reads_lock.Unlock()
+      ext.resolver_response_lock.Lock()
+      delete(ext.resolver_response, sig.UUID)
+      ext.resolver_response_lock.Unlock()
 
       ext.resolver_chans_lock.RLock()
       resolver_chan, exists := ext.resolver_chans[resolver_id]
@@ -1023,7 +1054,7 @@ func (ext *GQLExt) Process(ctx *Context, source NodeID, node *Node, signal Signa
 
       if exists == true {
         select {
-        case resolver_chan <- &sig:
+        case resolver_chan <- sig:
           ctx.Log.Logf("gql", "Forwarded to resolver %s, %+v", resolver_id, sig)
         default:
           ctx.Log.Logf("gql", "Resolver %s channel overflow %+v", resolver_id, sig)
@@ -1151,8 +1182,8 @@ func NewGQLExt(ctx *Context, listen string, tls_cert []byte, tls_key []byte, sta
   return &GQLExt{
     State: state,
     Listen: listen,
-    resolver_reads: map[uuid.UUID]uuid.UUID{},
-    resolver_chans: map[uuid.UUID]chan *ReadResultSignal{},
+    resolver_response: map[uuid.UUID]uuid.UUID{},
+    resolver_chans: map[uuid.UUID]chan Signal{},
     tls_cert: tls_cert,
     tls_key: tls_key,
   }, nil

gql_query.go

@@ -50,16 +50,16 @@ func ResolveNodes(ctx *ResolveContext, p graphql.ResolveParams, ids []NodeID) ([
     // Create a read signal, send it to the specified node, and add the wait to the response map if the send returns no error
     read_signal := NewReadSignal(ext_fields)
 
-    ctx.Ext.resolver_reads_lock.Lock()
-    ctx.Ext.resolver_reads[read_signal.UUID] = ctx.ID
-    ctx.Ext.resolver_reads_lock.Unlock()
+    ctx.Ext.resolver_response_lock.Lock()
+    ctx.Ext.resolver_response[read_signal.UUID] = ctx.ID
+    ctx.Ext.resolver_response_lock.Unlock()
 
     err = ctx.Context.Send(ctx.Server.ID, id, read_signal)
     read_signals[id] = read_signal.UUID
     if err != nil {
-      ctx.Ext.resolver_reads_lock.Lock()
-      delete(ctx.Ext.resolver_reads, read_signal.UUID)
-      ctx.Ext.resolver_reads_lock.Unlock()
+      ctx.Ext.resolver_response_lock.Lock()
+      delete(ctx.Ext.resolver_response, read_signal.UUID)
+      ctx.Ext.resolver_response_lock.Unlock()
       return nil, err
     }
   }
@@ -67,11 +67,11 @@ func ResolveNodes(ctx *ResolveContext, p graphql.ResolveParams, ids []NodeID) ([
   responses := []NodeResult{}
   for node_id, sig_id := range(read_signals) {
     // Wait for the response, returning an error on timeout
-    response, err := WaitForReadResult(ctx.Chan, time.Millisecond*100, sig_id)
+    response, err := WaitForResult(ctx.Chan, time.Millisecond*100, sig_id)
     if err != nil {
       return nil, err
     }
-    responses = append(responses, NodeResult{node_id, response})
+    responses = append(responses, NodeResult{node_id, response.(*ReadResultSignal)})
   }
 
   return responses, nil

gql_test.go

@@ -112,7 +112,7 @@ func TestGQLDB(t *testing.T) {
   fatalErr(t, err)
 
   _, err = WaitForSignal(ctx, listener_ext, 100*time.Millisecond, StatusSignalType, func(sig IDStringSignal) bool {
-    return sig.Str == "stopped" && sig.ID == gql.ID
+    return sig.Str == "stopped" && sig.NodeID == gql.ID
   })
   fatalErr(t, err)
 
@@ -130,7 +130,7 @@ func TestGQLDB(t *testing.T) {
   err = ctx.Send(gql_loaded.ID, gql_loaded.ID, StopSignal)
   fatalErr(t, err)
   _, err = WaitForSignal(ctx, listener_ext, 100*time.Millisecond, StatusSignalType, func(sig IDStringSignal) bool {
-    return sig.Str == "stopped" && sig.ID == gql_loaded.ID
+    return sig.Str == "stopped" && sig.NodeID == gql_loaded.ID
   })
   fatalErr(t, err)
 

lockable.go

@@ -169,11 +169,11 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
   switch state {
   case "unlock":
     if ext.Owner == nil {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_unlocked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_unlocked")))
     } else if source != *ext.Owner {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_owner")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_owner")))
     } else if ext.PendingOwner == nil {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_unlocking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_unlocking")))
     } else {
       if len(ext.Requirements) == 0 {
         ext.Owner = nil
@@ -199,11 +199,11 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
   case "unlocking":
     state, exists := ext.Requirements[source]
     if exists == false {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_requirement")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_requirement")))
     } else if state.Link != "linked" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("node_not_linked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("node_not_linked")))
     } else if state.Lock != "unlocking" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_unlocking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_unlocking")))
     }
 
   case "unlocked":
@@ -213,11 +213,11 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
 
     state, exists := ext.Requirements[source]
     if exists == false {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_requirement")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_requirement")))
     } else if state.Link != "linked" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_linked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_linked")))
     } else if state.Lock != "unlocking" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_unlocking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_unlocking")))
     } else {
       state.Lock = "unlocked"
       ext.Requirements[source] = state
@@ -248,11 +248,11 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
 
     state, exists := ext.Requirements[source]
     if exists == false {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_requirement")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_requirement")))
     } else if state.Link != "linked" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_linked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_linked")))
     } else if state.Lock != "locking" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_locking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_locking")))
     } else {
       state.Lock = "locked"
       ext.Requirements[source] = state
@@ -278,18 +278,18 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
   case "locking":
     state, exists := ext.Requirements[source]
     if exists == false {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_requirement")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_requirement")))
     } else if state.Link != "linked" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("node_not_linked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("node_not_linked")))
     } else if state.Lock != "locking" {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("not_locking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("not_locking")))
     }
 
   case "lock":
     if ext.Owner != nil {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_locked")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_locked")))
     } else if ext.PendingOwner != nil {
-      ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_locking")))
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_locking")))
     } else {
       owner := source
       if len(ext.Requirements) == 0 {
@@ -321,7 +321,7 @@ func (ext *LockableExt) HandleLockSignal(ctx *Context, source NodeID, node *Node
 func (ext *LockableExt) HandleLinkStartSignal(ctx *Context, source NodeID, node *Node, signal IDStringSignal) {
   ctx.Log.Logf("lockable", "LINK__START_SIGNAL: %s->%s %+v", source, node.ID, signal)
   link_type := signal.Str
-  target := signal.ID
+  target := signal.NodeID
   switch link_type {
   case "req":
     state, exists := ext.Requirements[target]
@@ -336,9 +336,9 @@ func (ext *LockableExt) HandleLinkStartSignal(ctx *Context, source NodeID, node
       }
     } else if exists == true {
       if state.Link == "linking" {
-        ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_linking_req")))
+        ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_linking_req")))
       } else if state.Link == "linked" {
-        ctx.Send(node.ID, source, NewErrorSignal(fmt.Errorf("already_req")))
+        ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), fmt.Errorf("already_req")))
       }
     } else if dep_exists == true {
       ctx.Send(node.ID, source, NewLinkStartSignal("already_dep", target))

node.go

@@ -209,6 +209,7 @@ func nodeLoop(ctx *Context, node *Node) error {
       err := Allowed(ctx, msg.Source, signal.Permission(), node)
       if err != nil {
         ctx.Log.Logf("signal", "SIGNAL_POLICY_ERR: %s", err)
+        ctx.Send(node.ID, msg.Source, NewErrorSignal(msg.Signal.ID(), err))
         continue
       }
     case <-node.TimeoutChan:
@@ -239,6 +240,7 @@ func nodeLoop(ctx *Context, node *Node) error {
 
     // Handle special signal types
     if signal.Type() == StopSignalType {
+      ctx.Send(node.ID, source, NewErrorSignal(signal.ID(), nil))
       node.Process(ctx, node.ID, NewStatusSignal("stopped", node.ID))
       break
     } else if signal.Type() == ReadSignalType {

signal.go

@@ -42,17 +42,26 @@ func (signal_type SignalType) Prefix() string { return "SIGNAL: " }
 type Signal interface {
   Serializable[SignalType]
   Direction() SignalDirection
+  ID() uuid.UUID
   Permission() Action
 }
 
-func WaitForReadResult(listener chan *ReadResultSignal, timeout time.Duration, id uuid.UUID) (*ReadResultSignal, error) {
+func WaitForResult(listener chan Signal, timeout time.Duration, id uuid.UUID) (Signal, error) {
   timeout_channel := time.After(timeout)
   var err error = nil
-  var result *ReadResultSignal = nil
-  select {
-  case result =<-listener:
-  case <-timeout_channel:
-    err = fmt.Errorf("timeout waiting for read response to %s", id)
+  var result Signal = nil
+  run := true
+  for run == true {
+    select {
+    case result=<-listener:
+      if result.ID() == id {
+        run = false
+      }
+    case <-timeout_channel:
+      result = nil
+      err = fmt.Errorf("timeout waiting for read response to %s", id)
+      run = false
+    }
   }
   return result, err
 }
@@ -88,6 +97,11 @@ func WaitForSignal[S Signal](ctx * Context, listener *ListenerExt, timeout time.
 type BaseSignal struct {
   SignalDirection SignalDirection `json:"direction"`
   SignalType SignalType `json:"type"`
+  uuid.UUID `json:"id"`
+}
+
+func (signal BaseSignal) ID() uuid.UUID {
+  return signal.UUID
 }
 
 func (signal BaseSignal) Type() SignalType {
@@ -108,6 +122,7 @@ func (signal BaseSignal) Serialize() ([]byte, error) {
 
 func NewBaseSignal(signal_type SignalType, direction SignalDirection) BaseSignal {
   signal := BaseSignal{
+    UUID: uuid.New(),
     SignalDirection: direction,
     SignalType: signal_type,
   }
@@ -133,9 +148,13 @@ type ErrorSignal struct {
   Error error `json:"error"`
 }
 
-func NewErrorSignal(err error) ErrorSignal {
+func NewErrorSignal(req_id uuid.UUID, err error) ErrorSignal {
   return ErrorSignal{
-    BaseSignal: NewDirectSignal(ErrorSignalType),
+    BaseSignal: BaseSignal{
+      Direct,
+      ErrorSignalType,
+      req_id,
+    },
     Error: err,
   }
 }
@@ -175,8 +194,8 @@ func (signal StringSignal) Serialize() ([]byte, error) {
 
 type IDStringSignal struct {
   BaseSignal
-  ID NodeID `json:"id"`
-  Str string `json:"state"`
+  NodeID `json:"node_id"`
+  Str string `json:"string"`
 }
 
 func (signal IDStringSignal) Serialize() ([]byte, error) {
@@ -194,7 +213,7 @@ func (signal IDStringSignal) String() string {
 func NewStatusSignal(status string, source NodeID) IDStringSignal {
   return IDStringSignal{
     BaseSignal: NewUpSignal(StatusSignalType),
-    ID: source,
+    NodeID: source,
     Str: status,
   }
 }
@@ -209,7 +228,7 @@ func NewLinkSignal(state string) StringSignal {
 func NewIDStringSignal(signal_type SignalType, direction SignalDirection, state string, id NodeID) IDStringSignal {
   return IDStringSignal{
     BaseSignal: NewBaseSignal(signal_type, direction),
-    ID: id,
+    NodeID: id,
     Str: state,
   }
 }
@@ -249,15 +268,17 @@ func NewReadSignal(exts map[ExtType][]string) ReadSignal {
 
 type ReadResultSignal struct {
   BaseSignal
-  uuid.UUID
   NodeType
   Extensions map[ExtType]map[string]interface{} `json:"extensions"`
 }
 
 func NewReadResultSignal(req_id uuid.UUID, node_type NodeType, exts map[ExtType]map[string]interface{}) ReadResultSignal {
   return ReadResultSignal{
-    BaseSignal: NewDirectSignal(ReadResultSignalType),
-    UUID: req_id,
+    BaseSignal: BaseSignal{
+      Direct,
+      ReadResultSignalType,
+      req_id,
+    },
     NodeType: node_type,
     Extensions: exts,
   }