more macaroon stuff

pkg/components/renderer/renderer.go

@@ -0,0 +1,69 @@
+package renderer
+
+import (
+	"crypto/md5"
+	"encoding/hex"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+
+	"github.com/torkelo/grafana-pro/pkg/log"
+	"github.com/torkelo/grafana-pro/pkg/setting"
+)
+
+type RenderOpts struct {
+	Url    string
+	Width  string
+	Height string
+}
+
+func RenderToPng(params *RenderOpts) (string, error) {
+	log.Info("PhantomRenderer::renderToPng url %v", params.Url)
+	binPath, _ := filepath.Abs(filepath.Join(setting.PhantomDir, "phantomjs"))
+	scriptPath, _ := filepath.Abs(filepath.Join(setting.PhantomDir, "render.js"))
+	pngPath, _ := filepath.Abs(filepath.Join(setting.ImagesDir, getHash(params.Url)))
+	pngPath = pngPath + ".png"
+
+	cmd := exec.Command(binPath, scriptPath, "url="+params.Url, "width="+params.Width, "height="+params.Height, "png="+pngPath)
+	stdout, err := cmd.StdoutPipe()
+
+	if err != nil {
+		return "", err
+	}
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		return "", err
+	}
+
+	err = cmd.Start()
+	if err != nil {
+		return "", err
+	}
+
+	go io.Copy(os.Stdout, stdout)
+	go io.Copy(os.Stdout, stderr)
+
+	done := make(chan error)
+	go func() {
+		cmd.Wait()
+		close(done)
+	}()
+
+	select {
+	case <-time.After(10 * time.Second):
+		if err := cmd.Process.Kill(); err != nil {
+			log.Error(4, "failed to kill: %v", err)
+		}
+	case <-done:
+	}
+
+	return pngPath, nil
+}
+
+func getHash(text string) string {
+	hasher := md5.New()
+	hasher.Write([]byte(text))
+	return hex.EncodeToString(hasher.Sum(nil))
+}