stats: Do not export base metric with sub-metrics on prometheus

This can confuse prometheus.

diff --git a/src/stats/stats-service-openmetrics.c b/src/stats/stats-service-openmetrics.c
index 0f5a3b5b0744f7a0e8aae1ad0b6bb6299bb7ec13..aaede7f09da67dc07a450cc2b637cdbb2922ef3b 100644 (file)
--- a/src/stats/stats-service-openmetrics.c
+++ b/src/stats/stats-service-openmetrics.c
@@ -34,7 +34,7 @@
    must match the regex [a-zA-Z_:][a-zA-Z0-9_:]*.
  */
 
-static void
+static bool
 openmetrics_export_submetrics(string_t *out, const struct metric *metric,
                              string_t *labels, bool count, int64_t timestamp);
 
@@ -184,17 +184,17 @@ openmetrics_export_submetric(string_t *out, const struct metric *metric,
                            timestamp);
        }
        size_t label_pos = str_len(labels);
-       openmetrics_export_submetrics(out, metric, labels, count, timestamp);
+       (void)openmetrics_export_submetrics(out, metric, labels, count, timestamp);
        str_truncate(labels, label_pos);
 }
 
-static void
+static bool
 openmetrics_export_submetrics(string_t *out, const struct metric *metric,
                              string_t *labels, bool count, int64_t timestamp)
 {
        struct metric *const *sub_metric;
        if (!array_is_created(&metric->sub_metrics))
-               return;
+               return FALSE;
        if (str_len(labels) > 0)
                str_append_c(labels, ',');
        str_append(labels, metric->group_by->field);
@@ -205,6 +205,7 @@ openmetrics_export_submetrics(string_t *out, const struct metric *metric,
                                             count, timestamp);
                str_truncate(labels, label_pos);
        }
+       return TRUE;
 }
 
 static void
@@ -216,6 +217,7 @@ openmetrics_export_metric(string_t *out, const struct metric *metric,
 
        string_t *labels = t_str_new(32);
        size_t label_pos;
+       bool has_submetric;
        openmetrics_export_metric_labels(labels, metric);
 
        /* Description */
@@ -233,22 +235,25 @@ openmetrics_export_metric(string_t *out, const struct metric *metric,
        str_append(out, "_count counter\n");
        /* Put all sub-metrics before the actual value */
        label_pos = str_len(labels);
-       openmetrics_export_submetrics(out, metric, labels, TRUE,
-                                     timestamp);
+       has_submetric = openmetrics_export_submetrics(out, metric, labels, TRUE,
+                                                     timestamp);
        str_truncate(labels, label_pos);
-       /* Metric name */
-       str_append(out, "dovecot_");
-       str_append(out, metric->name);
-       str_append(out, "_count");
-       /* Labels */
-       if (str_len(labels) > 0) {
-               str_append_c(out, '{');
-               str_append_str(out, labels);
-               str_append_c(out, '}');
+       if (!has_submetric) {
+               /* Metric name */
+               str_append(out, "dovecot_");
+               str_append(out, metric->name);
+               str_append(out, "_count");
+               /* Labels */
+               if (str_len(labels) > 0) {
+                       str_append_c(out, '{');
+                       str_append_str(out, labels);
+                       str_append_c(out, '}');
+               }
+               /* Value */
+               str_printfa(out, " %u %"PRId64"\n",
+                           stats_dist_get_count(metric->duration_stats), timestamp);
        }
-       /* Value */
-       str_printfa(out, " %u %"PRId64"\n\n",
-                   stats_dist_get_count(metric->duration_stats), timestamp);
+       str_append_c(out, '\n');
        /* Description */
        str_append(out, "# HELP dovecot_");
        str_append(out, metric->name);
@@ -263,23 +268,25 @@ openmetrics_export_metric(string_t *out, const struct metric *metric,
        str_append(out, metric->name);
        str_append(out, "_duration_usecs_sum counter\n");
        /* Put all sub-metrics before the actual value */
-       openmetrics_export_submetrics(out, metric, labels, FALSE,
-                                     timestamp);
+       has_submetric = openmetrics_export_submetrics(out, metric, labels, FALSE,
+                                                     timestamp);
        str_truncate(labels, label_pos);
-       /* Metric name*/
-       str_append(out, "dovecot_");
-       str_append(out, metric->name);
-       str_append(out, "_duration_usecs_sum");
-       /* Labels */
-       if (str_len(labels) > 0) {
-               str_append_c(out, '{');
-               str_append_str(out, labels);
-               str_append_c(out, '}');
+       if (!has_submetric) {
+               /* Metric name*/
+               str_append(out, "dovecot_");
+               str_append(out, metric->name);
+               str_append(out, "_duration_usecs_sum");
+               /* Labels */
+               if (str_len(labels) > 0) {
+                       str_append_c(out, '{');
+                       str_append_str(out, labels);
+                       str_append_c(out, '}');
+               }
+               /* Value */
+               str_printfa(out, " %"PRIu64" %"PRId64"\n",
+                           stats_dist_get_sum(metric->duration_stats),
+                           timestamp);
        }
-       /* Value */
-       str_printfa(out, " %"PRIu64" %"PRId64"\n",
-                   stats_dist_get_sum(metric->duration_stats),
-                   timestamp);
 }
 
 static void