Parse kopia errors (#1973)

* Parse kopia errors

* Add couple more cases

---------

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

pkg/kopia/command/parse_command_output.go

@@ -389,3 +389,26 @@ func IsEqualSnapshotCreateStats(a, b *SnapshotCreateStats) bool {
 		a.SizeEstimatedB == b.SizeEstimatedB &&
 		a.ProgressPercent == b.ProgressPercent
 }
+
+var ANSIEscapeCode = regexp.MustCompile(`\x1b[^m]*?m`)
+var kopiaErrorPattern = regexp.MustCompile(`(?:ERROR\s+|.*\<ERROR\>\s*|error\s+)(.*)`)
+
+// ErrorFromOutput parses the output of a kopia and returns an error, if found
+func ErrorsFromOutput(output string) []error {
+	if output == "" {
+		return nil
+	}
+
+	var err []error
+
+	lines := regexp.MustCompile("[\r\n]").Split(output, -1)
+	for _, l := range lines {
+		clean := ANSIEscapeCode.ReplaceAllString(l, "") // Strip all ANSI escape codes from line
+		match := kopiaErrorPattern.FindAllStringSubmatch(clean, 1)
+		if len(match) > 0 {
+			err = append(err, errors.New(match[0][1]))
+		}
+	}
+
+	return err
+}

pkg/kopia/command/parse_command_output_test.go

@@ -623,6 +623,34 @@ func (kParse *KopiaParseUtilsTestSuite) TestIsEqualSnapshotCreateStats(c *C) {
 	}
 }
 
+func (kParse *KopiaParseUtilsTestSuite) TestErrorsFromOutput(c *C) {
+	for caseIdx, tc := range []struct {
+		log            string
+		expectedErrors []string
+	}{
+		// Some real error case
+		{"ERROR open repository: repository is not connected. See https://kopia.io/docs/repositories/", []string{"open repository: repository is not connected. See https://kopia.io/docs/repositories/"}},
+		// The same as previous but with coloured ERROR word
+		{string([]byte{27, 91, 51, 49, 109, 69, 82, 82, 79, 82, 27, 91, 48, 109, 32, 111, 112, 101, 110, 32, 114, 101, 112, 111, 115, 105, 116, 111, 114, 121, 58, 32, 114, 101, 112, 111, 115, 105, 116, 111, 114, 121, 32, 105, 115, 32, 110, 111, 116, 32, 99, 111, 110, 110, 101, 99, 116, 101, 100, 46}), []string{"open repository: repository is not connected."}},
+		// Multiple error lines (seems not possible in real life, but just to cover this possibility)
+		{"ERROR open repository: repository is not connected. See https://kopia.io/docs/repositories/\r\nERROR another error", []string{"open repository: repository is not connected. See https://kopia.io/docs/repositories/", "another error"}},
+		// Error surrounded by other output
+		{"some text\r\nERROR open repository: repository is not connected. See https://kopia.io/docs/repositories/\r\nanother text line", []string{"open repository: repository is not connected. See https://kopia.io/docs/repositories/"}},
+		// No error in output
+		{"some text\r\nanother text line", []string{}},
+		{"  2009-11-10 23:00:00 UTC <ERROR> some error\n", []string{"some error"}},
+		{"error setting attributes: could not change owner/group", []string{"setting attributes: could not change owner/group"}},
+		{"error restoring: restore error: error copying: copy file: error creating file:", []string{"restoring: restore error: error copying: copy file: error creating file:"}},
+	} {
+		errs := ErrorsFromOutput(tc.log)
+		fc := Commentf("Failed for case #%v. Log: %s", caseIdx, tc.log)
+		c.Check(len(errs), Equals, len(tc.expectedErrors), fc)
+		for i, e := range errs {
+			c.Check(e.Error(), Equals, tc.expectedErrors[i], fc)
+		}
+	}
+}
+
 func marshalManifestList(c *C, manifestList []*snapshot.Manifest) string {
 	c.Assert(manifestList, NotNil)