Add edot to show

CHANGELOG.md

@@ -6,6 +6,7 @@
 
 ### Features
 - [#96](https://github.com/influxdb/kapacitor/issues/96): Use KAPACITOR_URL env var for setting the kapacitord url in the client.
+- [#109](https://github.com/influxdb/kapacitor/pull/109): Add throughput counts to DOT format in `kapacitor show` command, if task is executing.
 
 ### Bugfixes
 - [#102](https://github.com/influxdb/kapacitor/issues/102): Fix race when start/stoping timeTicker in batch.go

cmd/kapacitord/run/server_test.go

@@ -149,7 +149,7 @@ func TestServer_EnableTask(t *testing.T) {
 	if ti.TICKscript != tick {
 		t.Fatalf("unexpected TICKscript got %s exp %s", ti.TICKscript, tick)
 	}
-	dot := "digraph testTaskName {\nstream0 -> stream1;\n}"
+	dot := "digraph testTaskName {\nstream0 -> stream1 [label=\"0\"];\n}"
 	if ti.Dot != dot {
 		t.Fatalf("unexpected dot got %s exp %s", ti.Dot, dot)
 	}

edge.go

@@ -62,6 +62,10 @@ func newEdge(taskName, parentName, childName string, t pipeline.EdgeType, logSer
 	return e
 }
 
+func (e *Edge) collectedCount() string {
+	return e.statMap.Get(statCollected).String()
+}
+
 // Close the edge, this can only be called after all
 // collect calls to the edge have finished.
 func (e *Edge) Close() {

node.go

@@ -1,6 +1,7 @@
 package kapacitor
 
 import (
+	"bytes"
 	"fmt"
 	"log"
 	"runtime"
@@ -33,6 +34,9 @@ type Node interface {
 	closeChildEdges()
 	// abort parent edges
 	abortParentEdges()
+
+	// executing dot
+	edot(buf *bytes.Buffer)
 }
 
 //implementation of Node
@@ -148,3 +152,15 @@ func (n *node) closeChildEdges() {
 		child.Close()
 	}
 }
+
+func (n *node) edot(buf *bytes.Buffer) {
+	for i, c := range n.children {
+		buf.Write([]byte(
+			fmt.Sprintf("%s -> %s [label=\"%s\"];\n",
+				n.Name(),
+				c.Name(),
+				n.outs[i].collectedCount(),
+			),
+		))
+	}
+}

services/task_store/service.go

@@ -37,6 +37,7 @@ type Service struct {
 		StartTask(t *kapacitor.Task) (*kapacitor.ExecutingTask, error)
 		StopTask(name string) error
 		IsExecuting(name string) bool
+		ExecutingDot(name string) string
 	}
 	logger *log.Logger
 }
@@ -214,11 +215,16 @@ func (ts *Service) handleTask(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	executing := ts.TaskMaster.IsExecuting(name)
 	errMsg := raw.Error
 	dot := ""
 	task, err := ts.Load(name)
 	if err == nil {
-		dot = string(task.Dot())
+		if executing {
+			dot = ts.TaskMaster.ExecutingDot(name)
+		} else {
+			dot = string(task.Dot())
+		}
 	} else {
 		errMsg = err.Error()
 	}
@@ -230,7 +236,7 @@ func (ts *Service) handleTask(w http.ResponseWriter, r *http.Request) {
 		TICKscript: raw.TICKscript,
 		Dot:        dot,
 		Enabled:    ts.IsEnabled(name),
-		Executing:  ts.TaskMaster.IsExecuting(name),
+		Executing:  executing,
 		Error:      errMsg,
 	}
 

task.go

@@ -1,6 +1,7 @@
 package kapacitor
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"log"
@@ -283,6 +284,24 @@ func (et *ExecutingTask) registerOutput(name string, o Output) {
 	et.outputs[name] = o
 }
 
+// Return a graphviz .dot formatted byte array.
+// Label edges with relavant execution information.
+func (et *ExecutingTask) EDot() []byte {
+
+	var buf bytes.Buffer
+
+	buf.Write([]byte("digraph "))
+	buf.Write([]byte(et.Task.Name))
+	buf.Write([]byte(" {\n"))
+	et.walk(func(n Node) error {
+		n.edot(&buf)
+		return nil
+	})
+	buf.Write([]byte("}"))
+
+	return buf.Bytes()
+}
+
 // Create a  node from a given pipeline node.
 func (et *ExecutingTask) createNode(p pipeline.Node) (Node, error) {
 	switch t := p.(type) {

task_master.go

@@ -225,6 +225,16 @@ func (tm *TaskMaster) IsExecuting(name string) bool {
 	return executing
 }
 
+func (tm *TaskMaster) ExecutingDot(name string) string {
+	tm.mu.RLock()
+	defer tm.mu.RUnlock()
+	et, executing := tm.tasks[name]
+	if executing {
+		return string(et.EDot())
+	}
+	return ""
+}
+
 func (tm *TaskMaster) Stream(name string) (StreamCollector, error) {
 	tm.mu.Lock()
 	defer tm.mu.Unlock()