docker integration passes end-to-end test

Author: petar

cmd/circuit/start.go

@@ -30,9 +30,11 @@ func server(c *cli.Context) {
 	var err error
 
 	if c.Bool("docker") {
-		if err = docker.Init(); err != nil {
+		cmd, err := docker.Init()
+		if err != nil {
 			log.Fatalf("cannot use docker: %v", err)
 		}
+		log.Printf("Enabling docker elements, using %s", cmd)
 	}
 	// parse arguments
 	var tcpaddr = parseAddr(c) // server bind address

element/docker/docker_test.go element/docker/_docker_test.go

@@ -15,7 +15,7 @@ import (
 )
 
 func TestDocker(t *testing.T) {
-	if err := Init(); err != nil {
+	if _, err := Init(); err != nil {
 		t.Fatalf("init: %v", err)
 	}
 	run := ds.Run{

element/docker/docker.go

@@ -77,12 +77,10 @@ func (con *container) Wait() (_ *ds.Stat, err error) {
 }
 
 func (con *container) Stdin() io.WriteCloser {
-	println("*stdin")
 	return con.stdin
 }
 
 func (con *container) Stdout() io.ReadCloser {
-	println("*stdout")
 	return con.stdout
 }
 

element/docker/util.go

@@ -11,12 +11,13 @@ import (
 	"os/exec"
 )
 
-func Init() (err error) {
+func Init() (_ string, err error) {
 	dkr, err = exec.LookPath("docker")
 	if err != nil {
-		return err
+		return "", err
 	}
-	return exec.Command("dkr", "version").Run()
+	err = exec.Command(dkr, "version").Run()
+	return dkr, err
 }
 
 var dkr string