rcserver: implement prometheus metrics on a dedicated port - fixes #7940

fs/rc/rcserver/metrics_test.go

@@ -0,0 +1,88 @@
+package rcserver
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"regexp"
+	"testing"
+
+	_ "github.com/rclone/rclone/backend/local"
+	"github.com/rclone/rclone/fs/accounting"
+	"github.com/rclone/rclone/fs/config/configfile"
+	"github.com/rclone/rclone/fs/rc"
+	"github.com/stretchr/testify/require"
+)
+
+// Run a suite of tests
+func testMetricsServer(t *testing.T, tests []testRun, opt *rc.Options) {
+	t.Helper()
+	ctx := context.Background()
+	configfile.Install()
+	rcServer, err := newMetricsServer(ctx, opt)
+	require.NoError(t, err)
+	testURL := rcServer.server.URLs()[0]
+	mux := rcServer.server.Router()
+	emulateCalls(t, tests, mux, testURL)
+}
+
+// return an enabled rc
+func newMetricsTestOpt() rc.Options {
+	opt := rc.Opt
+	opt.MetricsHTTP.ListenAddr = []string{testBindAddress}
+	return opt
+}
+
+func TestMetrics(t *testing.T) {
+	stats := accounting.GlobalStats()
+	tests := makeMetricsTestCases(stats)
+	opt := newMetricsTestOpt()
+	testMetricsServer(t, tests, &opt)
+
+	// Test changing a couple options
+	stats.Bytes(500)
+	for i := 0; i < 30; i++ {
+		require.NoError(t, stats.DeleteFile(context.Background(), 0))
+	}
+	stats.Errors(2)
+	stats.Bytes(324)
+
+	tests = makeMetricsTestCases(stats)
+	testMetricsServer(t, tests, &opt)
+}
+
+func makeMetricsTestCases(stats *accounting.StatsInfo) (tests []testRun) {
+	tests = []testRun{{
+		Name:     "Bytes Transferred Metric",
+		URL:      "metrics",
+		Method:   "GET",
+		Status:   http.StatusOK,
+		Contains: regexp.MustCompile(fmt.Sprintf("rclone_bytes_transferred_total %d", stats.GetBytes())),
+	}, {
+		Name:     "Checked Files Metric",
+		URL:      "metrics",
+		Method:   "GET",
+		Status:   http.StatusOK,
+		Contains: regexp.MustCompile(fmt.Sprintf("rclone_checked_files_total %d", stats.GetChecks())),
+	}, {
+		Name:     "Errors Metric",
+		URL:      "metrics",
+		Method:   "GET",
+		Status:   http.StatusOK,
+		Contains: regexp.MustCompile(fmt.Sprintf("rclone_errors_total %d", stats.GetErrors())),
+	}, {
+		Name:     "Deleted Files Metric",
+		URL:      "metrics",
+		Method:   "GET",
+		Status:   http.StatusOK,
+		Contains: regexp.MustCompile(fmt.Sprintf("rclone_files_deleted_total %d", stats.GetDeletes())),
+	}, {
+		Name:     "Files Transferred Metric",
+		URL:      "metrics",
+		Method:   "GET",
+		Status:   http.StatusOK,
+		Contains: regexp.MustCompile(fmt.Sprintf("rclone_files_transferred_total %d", stats.GetTransfers())),
+	},
+	}
+	return
+}