1 files changed, 10 insertions, 6 deletions

diff --git a/exporting/prometheus/prometheus.c b/exporting/prometheus/prometheus.c
index 9f24ba1b0..90be5d455 100644
--- a/exporting/prometheus/prometheus.c
+++ b/exporting/prometheus/prometheus.c
@@ -335,6 +335,7 @@ void format_host_labels_prometheus(struct instance *instance, RRDHOST *host)
 
 struct format_prometheus_chart_label_callback {
     BUFFER *labels_buffer;
+    const char *labels_prefix;
 };
 
 static int format_prometheus_chart_label_callback(const char *name, const char *value, RRDLABEL_SRC ls, void *data) {
@@ -368,7 +369,7 @@ void format_chart_labels_prometheus(struct format_prometheus_chart_label_callbac
     else {
         plabel->labels_buffer = buffer_create(1024, NULL);
     }
-    buffer_sprintf(plabel->labels_buffer, "chart=\"%s\",dimension=\"%s\",family=\"%s\"", chart, dim, family);
+    buffer_sprintf(plabel->labels_buffer, "%1$schart=\"%2$s\",%1$sdimension=\"%3$s\",%1$sfamily=\"%4$s\"", plabel->labels_prefix, chart, dim, family);
 
     rrdlabels_walkthrough_read(st->rrdlabels, format_prometheus_chart_label_callback, plabel);
 }
@@ -454,6 +455,7 @@ static int print_host_variables_callback(const DICTIONARY_ITEM *item __maybe_unu
 
 struct gen_parameters {
     const char *prefix;
+    const char *labels_prefix;
     char *context;
     char *suffix;
 
@@ -525,12 +527,12 @@ static void generate_as_collected_prom_metric(BUFFER *wb,
     if (!homogeneous)
         buffer_sprintf(wb, "_%s", p->dimension);
 
-    buffer_sprintf(wb, "%s{chart=\"%s\"", p->suffix, p->chart);
+    buffer_sprintf(wb, "%s{%schart=\"%s\"", p->suffix, p->labels_prefix, p->chart);
 
     if (homogeneous)
-        buffer_sprintf(wb, ",dimension=\"%s\"", p->dimension);
+        buffer_sprintf(wb, ",%sdimension=\"%s\"", p->labels_prefix, p->dimension);
 
-    buffer_sprintf(wb, ",family=\"%s\"", p->family);
+    buffer_sprintf(wb, ",%sfamily=\"%s\"", p->labels_prefix, p->family);
 
     rrdlabels_walkthrough_read(chart_labels, format_prometheus_chart_label_callback, &local_label);
 
@@ -598,7 +600,7 @@ static void rrd_stats_api_v1_charts_allmetrics_prometheus(
 
     char labels[PROMETHEUS_LABELS_MAX + 1] = "";
     if (allhosts) {
-        snprintfz(labels, PROMETHEUS_LABELS_MAX, ",instance=\"%s\"", hostname);
+        snprintfz(labels, PROMETHEUS_LABELS_MAX, ",%sinstance=\"%s\"", instance->config.label_prefix, hostname);
      }
 
     if (instance->labels_buffer)
@@ -624,8 +626,9 @@ static void rrd_stats_api_v1_charts_allmetrics_prometheus(
     // for each chart
     RRDSET *st;
 
-    static struct format_prometheus_chart_label_callback plabels = {
+    struct format_prometheus_chart_label_callback plabels = {
         .labels_buffer = NULL,
+        .labels_prefix = instance->config.label_prefix,
     };
 
     STRING *prometheus = string_strdupz("prometheus");
@@ -684,6 +687,7 @@ static void rrd_stats_api_v1_charts_allmetrics_prometheus(
 
                         struct gen_parameters p;
                         p.prefix = prefix;
+                        p.labels_prefix = instance->config.label_prefix;
                         p.context = context;
                         p.suffix = suffix;
                         p.chart = chart;