Merge pull request #11 from Quentin-M/bzr_parsing

updater: Always use `bzr revno` to get Ubuntu db's revision number.

updater/fetchers/ubuntu.go

@@ -65,8 +65,6 @@ var (
 		"product": struct{}{},
 	}
 
-	branchedRegexp            = regexp.MustCompile(`Branched (\d+) revisions.`)
-	revisionRegexp            = regexp.MustCompile(`Now on revision (\d+).`)
 	affectsCaptureRegexp      = regexp.MustCompile(`(?P<release>.*)_(?P<package>.*): (?P<status>[^\s]*)( \(+(?P<note>[^()]*)\)+)?`)
 	affectsCaptureRegexpNames = affectsCaptureRegexp.SubexpNames()
 )
@@ -84,7 +82,6 @@ func (fetcher *UbuntuFetcher) FetchUpdate() (resp updater.FetcherResponse, err e
 	log.Info("fetching Ubuntu vulneratibilities")
 
 	// Check to see if the repository does not already exist.
-	var revisionNumber int
 	if _, pathExists := os.Stat(repositoryLocalPath); repositoryLocalPath == "" || os.IsNotExist(pathExists) {
 		// Create a temporary folder and download the repository.
 		p, err := ioutil.TempDir(os.TempDir(), "ubuntu-cve-tracker")
@@ -96,18 +93,24 @@ func (fetcher *UbuntuFetcher) FetchUpdate() (resp updater.FetcherResponse, err e
 		repositoryLocalPath = p + "/repository"
 
 		// Create the new repository.
-		revisionNumber, err = createRepository(repositoryLocalPath)
+		err = createRepository(repositoryLocalPath)
 		if err != nil {
 			return resp, err
 		}
 	} else {
 		// Update the repository that's already on disk.
-		revisionNumber, err = updateRepository(repositoryLocalPath)
+		err = updateRepository(repositoryLocalPath)
 		if err != nil {
 			return resp, err
 		}
 	}
 
+	// Get revision number.
+	revisionNumber, err := getRevisionNumber(repositoryLocalPath)
+	if err != nil {
+		return resp, err
+	}
+
 	// Get the latest revision number we successfully applied in the database.
 	dbRevisionNumber, err := database.GetFlagValue("ubuntuUpdater")
 	if err != nil {
@@ -200,7 +203,7 @@ func collectModifiedVulnerabilities(revision int, dbRevision, repositoryLocalPat
 	// Handle a database that needs upgrading.
 	out, err := utils.Exec(repositoryLocalPath, "bzr", "log", "--verbose", "-r"+strconv.Itoa(dbRevisionInt+1)+"..", "-n0")
 	if err != nil {
-		log.Errorf("could not get Ubuntu vulnerabilities repository logs: %s. output: %s", err, string(out))
+		log.Errorf("could not get Ubuntu vulnerabilities repository logs: %s. output: %s", err, out)
 		return nil, cerrors.ErrCouldNotDownload
 	}
 
@@ -218,61 +221,37 @@ func collectModifiedVulnerabilities(revision int, dbRevision, repositoryLocalPat
 	return modifiedCVE, nil
 }
 
-func createRepository(pathToRepo string) (int, error) {
+func createRepository(pathToRepo string) error {
 	// Branch repository
 	out, err := utils.Exec("/tmp/", "bzr", "branch", ubuntuTracker, pathToRepo)
 	if err != nil {
-		log.Errorf("could not branch Ubuntu repository: %s. output: %s", err, string(out))
-		return 0, cerrors.ErrCouldNotDownload
-	}
-
-	// Get revision number
-	regexpMatches := branchedRegexp.FindStringSubmatch(string(out))
-	if len(regexpMatches) != 2 {
-		log.Error("could not parse bzr branch output to get the revision number")
-		return 0, cerrors.ErrCouldNotDownload
-	}
-
-	revision, err := strconv.Atoi(regexpMatches[1])
-	if err != nil {
-		log.Error("could not parse bzr branch output to get the revision number")
-		return 0, cerrors.ErrCouldNotDownload
+		log.Errorf("could not branch Ubuntu repository: %s. output: %s", err, out)
+		return cerrors.ErrCouldNotDownload
 	}
-
-	return revision, err
+	return nil
 }
 
-func updateRepository(pathToRepo string) (int, error) {
+func updateRepository(pathToRepo string) error {
 	// Pull repository
 	out, err := utils.Exec(pathToRepo, "bzr", "pull", "--overwrite")
 	if err != nil {
-		log.Errorf("could not pull Ubuntu repository: %s. output: %s", err, string(out))
-		return 0, cerrors.ErrCouldNotDownload
-	}
-
-	// Get revision number
-	if strings.Contains(string(out), "No revisions or tags to pull") {
-		out, _ = utils.Exec(pathToRepo, "bzr", "revno")
-		revno, err := strconv.Atoi(string(out[:len(out)-1]))
-		if err != nil {
-			log.Errorf("could not parse Ubuntu repository revision number: %s. output: %s", err, string(out))
-			return 0, cerrors.ErrCouldNotDownload
-		}
-		return revno, nil
+		log.Errorf("could not pull Ubuntu repository: %s. output: %s", err, out)
+		return cerrors.ErrCouldNotDownload
 	}
+	return nil
+}
 
-	regexpMatches := revisionRegexp.FindStringSubmatch(string(out))
-	if len(regexpMatches) != 2 {
-		log.Error("could not parse bzr pull output to get the revision number")
+func getRevisionNumber(pathToRepo string) (int, error) {
+	out, err := utils.Exec(pathToRepo, "bzr", "revno")
+	if err != nil {
+		log.Errorf("could not get Ubuntu repository's revision number: %s. output: %s", err, out)
 		return 0, cerrors.ErrCouldNotDownload
 	}
-
-	revno, err := strconv.Atoi(regexpMatches[1])
+	revno, err := strconv.Atoi(strings.TrimSpace(string(out)))
 	if err != nil {
-		log.Error("could not parse bzr pull output to get the revision number")
+		log.Errorf("could not parse Ubuntu repository's revision number: %s. output: %s", err, out)
 		return 0, cerrors.ErrCouldNotDownload
 	}
-
 	return revno, nil
 }