minor refactor to prep for cards

card.go

@@ -0,0 +1,48 @@
+package docker
+
+import (
+	"encoding/base64"
+	"encoding/json"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+)
+
+func (p Plugin) writeCard() error {
+	cmd := exec.Command("docker", "inspect", p.Build.Name)
+	data, err := cmd.CombinedOutput()
+	if err != nil {
+		return err
+	}
+
+	out := map[string]interface{}{} // replace with docker inspect struct
+	if err := json.Unmarshal(data, &out); err != nil {
+		return err
+	}
+
+	card := map[string]interface{}{} // replace with card struct, populate with docker inspect output
+
+	writeCard( /*p.CardPath*/ "", &card)
+	return nil
+}
+
+func writeCard(path string, card interface{}) {
+	data, _ := json.Marshal(card)
+	switch {
+	case path == "/dev/stdout":
+		writeCardTo(os.Stdout, data)
+	case path == "/dev/stderr":
+		writeCardTo(os.Stderr, data)
+	case path != "":
+		ioutil.WriteFile(path, data, 0644)
+	}
+}
+
+func writeCardTo(out io.Writer, data []byte) {
+	encoded := base64.StdEncoding.EncodeToString(data)
+	io.WriteString(out, "\u001B]1338;")
+	io.WriteString(out, encoded)
+	io.WriteString(out, "\u001B]0m")
+	io.WriteString(out, "\n")
+}

docker.go

@@ -156,11 +156,6 @@ func (p Plugin) Exec() error {
 		}
 	}
 
-	if p.Cleanup {
-		cmds = append(cmds, commandRmi(p.Build.Name)) // docker rmi
-		cmds = append(cmds, commandPrune())           // docker system prune -f
-	}
-
 	// execute all commands in batch mode.
 	for _, cmd := range cmds {
 		cmd.Stdout = os.Stdout
@@ -179,6 +174,26 @@ func (p Plugin) Exec() error {
 		}
 	}
 
+	// output the adaptive card
+	if err := p.writeCard(); err != nil {
+		fmt.Printf("Could not create adaptive card. %s\n", err)
+	}
+
+	// execute cleanup routines in batch mode
+	if p.Cleanup {
+		// clear the slice
+		cmds = nil
+
+		cmds = append(cmds, commandRmi(p.Build.Name)) // docker rmi
+		cmds = append(cmds, commandPrune())           // docker system prune -f
+
+		for _, cmd := range cmds {
+			cmd.Stdout = os.Stdout
+			cmd.Stderr = os.Stderr
+			trace(cmd)
+		}
+	}
+
 	return nil
 }