Golang util.Close函数代码示例

// download fetches the content of the given location in GS and stores it at the given
// output path.
func (p *pdfProcessor) download(bucket, dir, fileName, outputPath string) error {
	objectPath := dir + "/" + fileName
	r, err := p.storageClient.Bucket(bucket).Object(objectPath).NewReader(context.Background())
	if err != nil {
		return err
	}
	defer util.Close(r)

	tempFile, err := ioutil.TempFile(p.pdfCacheDir, "pdfingestion-download")
	if err != nil {
		return err
	}

	_, err = io.Copy(tempFile, r)
	util.Close(tempFile)
	if err != nil {
		util.Remove(tempFile.Name())
		return err
	}

	if err := os.Rename(tempFile.Name(), outputPath); err != nil {
		return err
	}

	glog.Infof("Downloaded: %s/%s", bucket, objectPath)
	return nil
}

// monitorIssueTracker reads the counts for all the types of issues in the skia
// issue tracker (code.google.com/p/skia) and stuffs the counts into Graphite.
func monitorIssueTracker() {
	c := &http.Client{
		Transport: &http.Transport{
			Dial: dialTimeout,
		},
	}

	if *useMetadata {
		*apikey = metadata.Must(metadata.ProjectGet(metadata.APIKEY))
	}

	// Create a new metrics registry for the issue tracker metrics.
	addr, err := net.ResolveTCPAddr("tcp", *graphiteServer)
	if err != nil {
		glog.Fatalln("Failed to resolve the Graphite server: ", err)
	}
	issueRegistry := metrics.NewRegistry()
	go graphite.Graphite(issueRegistry, common.SAMPLE_PERIOD, "issues", addr)

	// IssueStatus has all the info we need to capture and record a single issue status. I.e. capture
	// the count of all issues with a status of "New".
	type IssueStatus struct {
		Name   string
		Metric metrics.Gauge
		URL    string
	}

	allIssueStatusLabels := []string{
		"New", "Accepted", "Unconfirmed", "Started", "Fixed", "Verified", "Invalid", "WontFix", "Done", "Available", "Assigned",
	}

	issueStatus := []*IssueStatus{}
	for _, issueName := range allIssueStatusLabels {
		issueStatus = append(issueStatus, &IssueStatus{
			Name:   issueName,
			Metric: metrics.NewRegisteredGauge(strings.ToLower(issueName), issueRegistry),
			URL:    "https://www.googleapis.com/projecthosting/v2/projects/skia/issues?fields=totalResults&key=" + *apikey + "&status=" + issueName,
		})
	}

	liveness := imetrics.NewLiveness("issue-tracker")
	for _ = range time.Tick(ISSUE_TRACKER_PERIOD) {
		for _, issue := range issueStatus {
			resp, err := c.Get(issue.URL)
			jsonResp := map[string]int64{}
			dec := json.NewDecoder(resp.Body)
			if err := dec.Decode(&jsonResp); err != nil {
				glog.Warningf("Failed to decode JSON response: %s", err)
				util.Close(resp.Body)
				continue
			}
			issue.Metric.Update(jsonResp["totalResults"])
			glog.Infof("Num Issues: %s - %d", issue.Name, jsonResp["totalResults"])
			if err == nil && resp.Body != nil {
				util.Close(resp.Body)
			}
		}
		liveness.Update()
	}
}

// monitorIssueTracker reads the counts for all the types of issues in the Skia
// issue tracker (bugs.chromium.org/p/skia) and stuffs the counts into Graphite.
func monitorIssueTracker(c *http.Client) {
	// Create a new metrics registry for the issue tracker metrics.
	addr, err := net.ResolveTCPAddr("tcp", *graphiteServer)
	if err != nil {
		glog.Fatalln("Failed to resolve the Graphite server: ", err)
	}
	issueRegistry := metrics.NewRegistry()
	go graphite.Graphite(issueRegistry, common.SAMPLE_PERIOD, "issues", addr)

	// IssueStatus has all the info we need to capture and record a single issue status. I.e. capture
	// the count of all issues with a status of "New".
	type IssueStatus struct {
		Name   string
		Metric metrics.Gauge
		URL    string
	}

	allIssueStatusLabels := []string{
		"New", "Accepted", "Unconfirmed", "Started", "Fixed", "Verified", "Invalid", "WontFix", "Done", "Available", "Assigned",
	}

	issueStatus := []*IssueStatus{}
	for _, issueName := range allIssueStatusLabels {
		q := url.Values{}
		q.Set("fields", "totalResults")
		q.Set("status", issueName)
		issueStatus = append(issueStatus, &IssueStatus{
			Name:   issueName,
			Metric: metrics.NewRegisteredGauge(strings.ToLower(issueName), issueRegistry),
			URL:    issues.MONORAIL_BASE_URL + "?" + q.Encode(),
		})
	}

	liveness := imetrics.NewLiveness("issue-tracker")
	for _ = range time.Tick(ISSUE_TRACKER_PERIOD) {
		for _, issue := range issueStatus {
			resp, err := c.Get(issue.URL)
			if err != nil {
				glog.Errorf("Failed to retrieve response from %s: %s", issue.URL, err)
				continue
			}
			jsonResp := map[string]int64{}
			dec := json.NewDecoder(resp.Body)
			if err := dec.Decode(&jsonResp); err != nil {
				glog.Warningf("Failed to decode JSON response: %s", err)
				util.Close(resp.Body)
				continue
			}
			issue.Metric.Update(jsonResp["totalResults"])
			glog.Infof("Num Issues: %s - %d", issue.Name, jsonResp["totalResults"])
			if err == nil && resp.Body != nil {
				util.Close(resp.Body)
			}
		}
		liveness.Update()
	}
}

// This does the following:
//   `pdftoppm -r 72 -f 1 -l 1 < $PDF 2>/dev/null | pnmtopng 2> /dev/null > $PNG`
func (Poppler) Rasterize(pdfInputPath, pngOutputPath string) error {
	if !(Poppler{}).Enabled() {
		return fmt.Errorf("pdftoppm or pnmtopng is missing")
	}

	pdftoppm := exec.Command(pdftoppmExecutable, "-r", "72", "-f", "1", "-l", "1")
	pnmtopng := exec.Command(pnmtopngExecutable)

	defer processKiller(pdftoppm)
	defer processKiller(pnmtopng)

	pr, pw, err := os.Pipe()
	if err != nil {
		return err
	}
	defer fileCloser(pw)
	defer fileCloser(pr)
	pdftoppm.Stdout = pw
	pnmtopng.Stdin = pr

	iFile, err := os.Open(pdfInputPath)
	if err != nil {
		return err
	}
	defer util.Close(iFile)
	pdftoppm.Stdin = iFile

	oFile, err := os.Create(pngOutputPath)
	if err != nil {
		return err
	}
	defer util.Close(oFile)
	pnmtopng.Stdout = oFile

	if err := pdftoppm.Start(); err != nil {
		return err
	}
	if err := pnmtopng.Start(); err != nil {
		return err
	}

	go func() {
		time.Sleep(5 * time.Second)
		_ = pdftoppm.Process.Kill()
	}()
	if err := pdftoppm.Wait(); err != nil {
		return err
	}
	if err := pw.Close(); err != nil {
		return err
	}
	if err := pnmtopng.Wait(); err != nil {
		return err
	}
	return nil
}

// findBadBinaryPaths looks through all the afl-fuzz directories contained in the passed in path and
// returns the path to all files that are in a crash* folder that are not already in
// 'alreadyFoundBinaries'
// It also sends them to the forAnalysis channel when it finds them.
// The output from afl-fuzz looks like:
// $AFL_ROOT/
//		-fuzzer0/
//			-crashes/  <-- bad binary fuzzes end up here
//			-hangs/
//			-queue/
//			-fuzzer_stats
//		-fuzzer1/
//		...
func findBadBinaryPaths(alreadyFoundBinaries *SortedStringSlice) ([]string, error) {
	badBinaryPaths := make([]string, 0)

	aflDir, err := os.Open(config.Generator.AflOutputPath)
	if err != nil {
		return nil, err
	}
	defer util.Close(aflDir)

	fuzzerFolders, err := aflDir.Readdir(-1)
	if err != nil {
		return nil, err
	}

	for _, fuzzerFolderInfo := range fuzzerFolders {
		// fuzzerFolderName an os.FileInfo like fuzzer0, fuzzer1
		path := filepath.Join(config.Generator.AflOutputPath, fuzzerFolderInfo.Name())
		fuzzerDir, err := os.Open(path)
		if err != nil {
			return nil, err
		}
		defer util.Close(fuzzerDir)

		fuzzerContents, err := fuzzerDir.Readdir(-1)
		if err != nil {
			return nil, err
		}
		for _, info := range fuzzerContents {
			// Look through fuzzerN/crashes
			if info.IsDir() && strings.HasPrefix(info.Name(), "crashes") {
				crashPath := filepath.Join(path, info.Name())
				crashDir, err := os.Open(crashPath)
				if err != nil {
					return nil, err
				}
				defer util.Close(crashDir)

				crashContents, err := crashDir.Readdir(-1)
				if err != nil {
					return nil, err
				}
				for _, crash := range crashContents {
					// Make sure the files are actually crashable files we haven't found before
					if crash.Name() != "README.txt" {
						if fuzzPath := filepath.Join(crashPath, crash.Name()); !alreadyFoundBinaries.Contains(fuzzPath) {
							badBinaryPaths = append(badBinaryPaths, fuzzPath)
						}
					}
				}
			}
		}
	}
	return badBinaryPaths, nil
}

// RequestBuild adds a request for the given build.
func (c *Client) RequestBuild(builder, master, commit, repo, author string) (*Build, error) {
	p := buildBucketParameters{
		BuilderName: builder,
		Changes: []*buildBucketChange{
			&buildBucketChange{
				Author: &buildBucketAuthor{
					Email: author,
				},
				Repository: repo,
				Revision:   commit,
			},
		},
		Properties: map[string]string{
			"reason": "Triggered by SkiaScheduler",
		},
	}
	jsonParams, err := json.Marshal(p)
	if err != nil {
		return nil, err
	}
	body := buildBucketRequest{
		Bucket:         fmt.Sprintf("master.%s", master),
		ParametersJSON: string(jsonParams),
	}
	jsonBody, err := json.Marshal(body)
	if err != nil {
		return nil, err
	}
	url := apiUrl + "/builds"
	req, err := http.NewRequest("PUT", url, bytes.NewReader(jsonBody))
	if err != nil {
		return nil, err
	}
	req.Header.Set("Content-Type", "application/json; charset=utf-8")
	resp, err := c.Do(req)
	if err != nil {
		return nil, err
	}
	if resp.StatusCode != http.StatusOK {
		defer util.Close(resp.Body)
		b, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("Failed to schedule build (code %s); couldn't read response body: %v", resp.Status, err)
		}
		return nil, fmt.Errorf("Response code is %s. Response body:\n%s", resp.Status, string(b))
	}
	defer util.Close(resp.Body)
	var res buildBucketResponse
	if err := json.NewDecoder(resp.Body).Decode(&res); err != nil {
		return nil, fmt.Errorf("Failed to decode response body: %v", err)
	}
	return res.Build, nil
}

func mergeUploadCSVFiles(runID string, gs *util.GsUtil) ([]string, error) {
	localOutputDir := filepath.Join(util.StorageDir, util.BenchmarkRunsDir, runID)
	skutil.MkdirAll(localOutputDir, 0700)
	noOutputSlaves := []string{}
	// Copy outputs from all slaves locally.
	for i := 0; i < util.NumWorkers(); i++ {
		workerNum := i + 1
		workerLocalOutputPath := filepath.Join(localOutputDir, fmt.Sprintf("slave%d", workerNum)+".csv")
		workerRemoteOutputPath := filepath.Join(util.BenchmarkRunsDir, runID, fmt.Sprintf("slave%d", workerNum), "outputs", runID+".output")
		respBody, err := gs.GetRemoteFileContents(workerRemoteOutputPath)
		if err != nil {
			glog.Errorf("Could not fetch %s: %s", workerRemoteOutputPath, err)
			noOutputSlaves = append(noOutputSlaves, fmt.Sprintf(util.WORKER_NAME_TEMPLATE, workerNum))
			continue
		}
		defer skutil.Close(respBody)
		out, err := os.Create(workerLocalOutputPath)
		if err != nil {
			return noOutputSlaves, fmt.Errorf("Unable to create file %s: %s", workerLocalOutputPath, err)
		}
		defer skutil.Close(out)
		defer skutil.Remove(workerLocalOutputPath)
		if _, err = io.Copy(out, respBody); err != nil {
			return noOutputSlaves, fmt.Errorf("Unable to copy to file %s: %s", workerLocalOutputPath, err)
		}
	}
	// Call csv_merger.py to merge all results into a single results CSV.
	_, currentFile, _, _ := runtime.Caller(0)
	pathToPyFiles := filepath.Join(
		filepath.Dir((filepath.Dir(filepath.Dir(filepath.Dir(currentFile))))),
		"py")
	pathToCsvMerger := filepath.Join(pathToPyFiles, "csv_merger.py")
	outputFileName := runID + ".output"
	args := []string{
		pathToCsvMerger,
		"--csv_dir=" + localOutputDir,
		"--output_csv_name=" + filepath.Join(localOutputDir, outputFileName),
	}
	err := util.ExecuteCmd("python", args, []string{}, util.CSV_MERGER_TIMEOUT, nil, nil)
	if err != nil {
		return noOutputSlaves, fmt.Errorf("Error running csv_merger.py: %s", err)
	}
	// Copy the output file to Google Storage.
	remoteOutputDir := filepath.Join(util.BenchmarkRunsDir, runID, "consolidated_outputs")
	if err := gs.UploadFile(outputFileName, localOutputDir, remoteOutputDir); err != nil {
		return noOutputSlaves, fmt.Errorf("Unable to upload %s to %s: %s", outputFileName, remoteOutputDir, err)
	}
	return noOutputSlaves, nil
}

func mergeUploadCSVFiles(runID string, gs *util.GsUtil) error {
	localOutputDir := filepath.Join(util.StorageDir, util.BenchmarkRunsDir, runID)
	skutil.MkdirAll(localOutputDir, 0700)
	// Copy outputs from all slaves locally.
	for i := 0; i < util.NUM_WORKERS; i++ {
		workerNum := i + 1
		workerLocalOutputPath := filepath.Join(localOutputDir, fmt.Sprintf("slave%d", workerNum)+".csv")
		workerRemoteOutputPath := filepath.Join(util.BenchmarkRunsDir, runID, fmt.Sprintf("slave%d", workerNum), "outputs", runID+".output")
		respBody, err := gs.GetRemoteFileContents(workerRemoteOutputPath)
		if err != nil {
			glog.Errorf("Could not fetch %s: %s", workerRemoteOutputPath, err)
			// TODO(rmistry): Should we instead return here? We can only return
			// here if all 100 slaves reliably run without any failures which they
			// really should.
			continue
		}
		defer skutil.Close(respBody)
		out, err := os.Create(workerLocalOutputPath)
		if err != nil {
			return fmt.Errorf("Unable to create file %s: %s", workerLocalOutputPath, err)
		}
		defer skutil.Close(out)
		defer skutil.Remove(workerLocalOutputPath)
		if _, err = io.Copy(out, respBody); err != nil {
			return fmt.Errorf("Unable to copy to file %s: %s", workerLocalOutputPath, err)
		}
	}
	// Call csv_merger.py to merge all results into a single results CSV.
	_, currentFile, _, _ := runtime.Caller(0)
	pathToPyFiles := filepath.Join(
		filepath.Dir((filepath.Dir(filepath.Dir(filepath.Dir(currentFile))))),
		"py")
	pathToCsvMerger := filepath.Join(pathToPyFiles, "csv_merger.py")
	outputFileName := runID + ".output"
	args := []string{
		pathToCsvMerger,
		"--csv_dir=" + localOutputDir,
		"--output_csv_name=" + filepath.Join(localOutputDir, outputFileName),
	}
	if err := util.ExecuteCmd("python", args, []string{}, 1*time.Hour, nil, nil); err != nil {
		return fmt.Errorf("Error running csv_merger.py: %s", err)
	}
	// Copy the output file to Google Storage.
	remoteOutputDir := filepath.Join(util.BenchmarkRunsDir, runID, "consolidated_outputs")
	if err := gs.UploadFile(outputFileName, localOutputDir, remoteOutputDir); err != nil {
		return fmt.Errorf("Unable to upload %s to %s: %s", outputFileName, remoteOutputDir, err)
	}
	return nil
}

// JSON decodes the provided resultsFile and uploads results to chromeperf.appspot.com
func uploadResultsToPerfDashboard(resultsFile string, client *http.Client) error {
	jsonFile, err := os.Open(resultsFile)
	defer skutil.Close(jsonFile)
	if err != nil {
		return fmt.Errorf("Could not open %s: %s", resultsFile, err)
	}
	// Read the JSON and convert to dashboard JSON v1.
	var chartData interface{}
	if err := json.NewDecoder(jsonFile).Decode(&chartData); err != nil {
		return fmt.Errorf("Could not parse %s: %s", resultsFile, err)
	}
	// TODO(rmistry): Populate the below with data that can be monitored.
	versions := map[string]string{
		"chromium": *gitHash,
	}
	supplemental := map[string]string{}
	// Create a custom dictionary and convert it to JSON.
	dashboardFormat := map[string]interface{}{
		"master":       getCamelCaseMasterName(*buildbotMaster),
		"bot":          *buildbotBuilder,
		"chart_data":   chartData,
		"point_id":     time.Now().Unix(),
		"versions":     versions,
		"supplemental": supplemental,
	}
	marshalledData, err := json.Marshal(dashboardFormat)
	if err != nil {
		return fmt.Errorf("Could not create dashboard JSON for %s: %s", resultsFile, err)
	}

	// Post the above to https://chromeperf.appspot.com/add_point with one parameter called data.
	postData := url.Values{}
	postData.Set("data", string(marshalledData))
	req, err := http.NewRequest("POST", "https://chromeperf.appspot.com/add_point", strings.NewReader(postData.Encode()))
	if err != nil {
		return fmt.Errorf("Could not create HTTP request for %s: %s", resultsFile, err)
	}
	resp, err := client.Do(req)
	if err != nil {
		return fmt.Errorf("Could not post to chromeperf for %s: %s", resultsFile, err)
	}
	defer skutil.Close(resp.Body)
	if resp.StatusCode != 200 {
		return fmt.Errorf("Could not post to chromeperf for %s, response status code was %d", resultsFile, resp.StatusCode)
	}
	glog.Infof("Successfully uploaded the following to chromeperf: %s", string(marshalledData))
	return nil
}

func (fs *FileDiffStore) writeDiffMetricsToFileCache(baseName string, diffMetrics *diff.DiffMetrics) error {
	// Lock the mutex before writing to the local diff directory.
	fs.diffDirLock.Lock()
	defer fs.diffDirLock.Unlock()

	// Make paths relative. This has to be reversed in getDiffMetricsFromFileCache.
	fName, err := fs.createDiffMetricPath(baseName)
	if err != nil {
		return err
	}

	f, err := os.Create(fName)
	if err != nil {
		return fmt.Errorf("Unable to create file %s: %s", fName, err)
	}
	defer util.Close(f)

	d, err := json.MarshalIndent(diffMetrics, "", "    ")
	if err != nil {
		return fmt.Errorf("Failed to encode to JSON: %s", err)
	}
	if _, err := f.Write(d); err != nil {
		return fmt.Errorf("Failed to write to file: %v", err)
	}
	return nil
}

// showcutHandler handles the POST requests of the shortcut page.
//
// Shortcuts are of the form:
//
//    {
//       "scale": 0,
//       "tiles": [-1],
//       "hash": "a1092123890...",
//       "ids": [
//            "x86:...",
//            "x86:...",
//            "x86:...",
//       ]
//    }
//
// hash - The git hash of where a step was detected. Can be null.
//
func shortcutHandler(w http.ResponseWriter, r *http.Request) {
	// TODO(jcgregorio): Add unit tests.
	match := shortcutHandlerPath.FindStringSubmatch(r.URL.Path)
	if match == nil {
		http.NotFound(w, r)
		return
	}
	if r.Method == "POST" {
		// check header
		if ct := r.Header.Get("Content-Type"); ct != "application/json" {
			util.ReportError(w, r, fmt.Errorf("Error: received %s", ct), "Invalid content type.")
			return
		}
		defer util.Close(r.Body)
		id, err := shortcut.Insert(r.Body)
		if err != nil {
			util.ReportError(w, r, err, "Error inserting shortcut.")
			return
		}
		w.Header().Set("Content-Type", "application/json")
		enc := json.NewEncoder(w)
		if err := enc.Encode(map[string]string{"id": id}); err != nil {
			glog.Errorf("Failed to write or encode output: %s", err)
		}
	} else {
		http.NotFound(w, r)
	}
}

// See the ingester.ResultIngester interface.
func (i GoldIngester) Ingest(tt *ingester.TileTracker, opener ingester.Opener, fileInfo *ingester.ResultsFileLocation, counter metrics.Counter) error {
	r, err := opener()
	if err != nil {
		return err
	}
	defer util.Close(r)

	res, err := ParseDMResultsFromReader(r)
	if err != nil {
		return err
	}

	// Run the pre-ingestion hook.
	if i.preIngestionHook != nil {
		if err := i.preIngestionHook(res); err != nil {
			return fmt.Errorf("Error running pre-ingestion hook: %s", err)
		}
	}

	if res.GitHash != "" {
		glog.Infof("Got Git hash: %s", res.GitHash)
		if err := tt.Move(res.GitHash); err != nil {
			return fmt.Errorf("Failed to move to correct Tile: %s: %s", res.GitHash, err)
		}
		addResultToTile(res, tt.Tile(), tt.Offset(res.GitHash), counter)
	} else {
		return fmt.Errorf("Missing hash.")
	}

	return nil
}

func addBuildCommentHandler(w http.ResponseWriter, r *http.Request) {
	defer timer.New("addBuildCommentHandler").Stop()
	if !userHasEditRights(r) {
		util.ReportError(w, r, fmt.Errorf("User does not have edit rights."), "User does not have edit rights.")
		return
	}
	w.Header().Set("Content-Type", "application/json")
	cache, err := getCommitCache(w, r)
	if err != nil {
		return
	}
	buildId, err := strconv.ParseInt(mux.Vars(r)["buildId"], 10, 32)
	if err != nil {
		util.ReportError(w, r, err, fmt.Sprintf("Invalid build id: %v", err))
		return
	}
	comment := struct {
		Comment string `json:"comment"`
	}{}
	if err := json.NewDecoder(r.Body).Decode(&comment); err != nil {
		util.ReportError(w, r, err, fmt.Sprintf("Failed to add comment: %v", err))
		return
	}
	defer util.Close(r.Body)
	c := buildbot.BuildComment{
		BuildId:   int(buildId),
		User:      login.LoggedInAs(r),
		Timestamp: float64(time.Now().UTC().Unix()),
		Message:   comment.Comment,
	}
	if err := cache.AddBuildComment(int(buildId), &c); err != nil {
		util.ReportError(w, r, err, fmt.Sprintf("Failed to add comment: %v", err))
		return
	}
}

// AreTimeStampsEqual checks whether the TIMESTAMP in the local dir matches the
// TIMESTAMP in the remote Google Storage dir.
func (gs *GsUtil) AreTimeStampsEqual(localDir, gsDir string) (bool, error) {
	// Get timestamp from the local directory.
	localTimestampPath := filepath.Join(localDir, TIMESTAMP_FILE_NAME)
	fileContent, err := ioutil.ReadFile(localTimestampPath)
	if err != nil {
		return false, fmt.Errorf("Could not read %s: %s", localTimestampPath, err)
	}
	localTimestamp := strings.Trim(string(fileContent), "\n")

	// Get timestamp from the Google Storage directory.
	gsTimestampPath := filepath.Join(gsDir, TIMESTAMP_FILE_NAME)
	respBody, err := gs.GetRemoteFileContents(gsTimestampPath)
	if err != nil {
		return false, err
	}
	defer util.Close(respBody)
	resp, err := ioutil.ReadAll(respBody)
	if err != nil {
		return false, err
	}
	gsTimestamp := strings.Trim(string(resp), "\n")

	// Return the comparison of the two timestamps.
	return localTimestamp == gsTimestamp, nil
}

func writeOutAllSourceImages() {
	// Pull all the source images from the db and write them out to inout.
	rows, err := db.Query("SELECT id, image, create_ts FROM source_images ORDER BY create_ts DESC")
	if err != nil {
		glog.Errorf("Failed to open connection to SQL server: %q\n", err)
		panic(err)
	}
	defer util.Close(rows)
	for rows.Next() {
		var id int
		var image []byte
		var create_ts time.Time
		if err := rows.Scan(&id, &image, &create_ts); err != nil {
			glog.Errorf("failed to fetch from database: %q", err)
			continue
		}
		filename := fmt.Sprintf(filepath.Join(config.Fiddle.InoutPath, "image-%d.png"), id)
		if _, err := os.Stat(filename); os.IsExist(err) {
			glog.Infof("Skipping write since file exists: %q", filename)
			continue
		}
		if err := ioutil.WriteFile(filename, image, 0666); err != nil {
			glog.Errorf("failed to write image file: %q", err)
		}
	}
}