MAJOR: contrib/prometheus-exporter: move ftd/bkd/srv states to labels
this patch is a breaking change between v2.3 and v2.4: we move from
using gauge value for frontend/backend/servers states to labels values.
the main motivation being I realised it is very difficult to make use of
it without hard coded quirks on prometheus client side; especially
because the main use is often to group by state, which is harder when
the state is the value of the metric.
in order to achieve that we iterate on the status metric to generate
labels, and so as many metrics.
this is the first step to resolve github issue #1029
A second step should address health check states.
Signed-off-by: William Dauchy <wdauchy@gmail.com>
diff --git a/contrib/prometheus-exporter/service-prometheus.c b/contrib/prometheus-exporter/service-prometheus.c
index dac301f..43eb2f1 100644
--- a/contrib/prometheus-exporter/service-prometheus.c
+++ b/contrib/prometheus-exporter/service-prometheus.c
@@ -295,7 +295,7 @@
[ST_F_ERESP] = IST("Total number of response errors."),
[ST_F_WRETR] = IST("Total number of retry warnings."),
[ST_F_WREDIS] = IST("Total number of redispatch warnings."),
- [ST_F_STATUS] = IST("Current status of the service (frontend: 0=STOP, 1=UP - backend: 0=DOWN, 1=UP - server: 0=DOWN, 1=UP, 2=MAINT, 3=DRAIN, 4=NOLB)."),
+ [ST_F_STATUS] = IST("Current status of the service."),
[ST_F_WEIGHT] = IST("Service weight."),
[ST_F_ACT] = IST("Current number of active servers."),
[ST_F_BCK] = IST("Current number of backup servers."),
@@ -530,8 +530,8 @@
* success. Otherwise if <out> length exceeds <max>, it returns 0.
*/
static int promex_dump_metric(struct appctx *appctx, struct htx *htx, struct ist prefix,
- const struct promex_metric *metric, struct field *val,
- struct ist *out, size_t max)
+ const struct promex_metric *metric, struct field *val,
+ struct ist metric_label, struct ist *out, size_t max)
{
struct ist name = { .ptr = (char[PROMEX_MAX_NAME_LEN]){ 0 }, .len = 0 };
size_t len = out->len;
@@ -572,6 +572,8 @@
(srv && istcat(out, ist("\""), max) == -1) ||
(label.len && istcat(out, ist(","), max) == -1) ||
(label.len && istcat(out, label, max) == -1) ||
+ (metric_label.len && istcat(out, ist(","), max) == -1) ||
+ (metric_label.len && istcat(out, metric_label, max) == -1) ||
istcat(out, ist("} "), max) == -1)
goto full;
}
@@ -618,7 +620,8 @@
val = info[appctx->st2];
}
- if (!promex_dump_metric(appctx, htx, prefix, &promex_global_metrics[appctx->st2], &val, &out, max))
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_global_metrics[appctx->st2],
+ &val, IST_NULL, &out, max))
goto full;
appctx->ctx.stats.flags |= PROMEX_FL_METRIC_HDR;
@@ -636,6 +639,19 @@
goto end;
}
+/* Helper to generate state labels for ftd/bkd/srv */
+static int promex_state_label(struct ist *metric_label, struct ist state)
+{
+ struct buffer *state_label = get_trash_chunk();
+
+ *metric_label = ist2(state_label->area, 0);
+ if (istcat(metric_label, ist("state=\""), state_label->size) == -1 ||
+ istcat(metric_label, state, state_label->size) == -1 ||
+ istcat(metric_label, ist("\""), state_label->size) == -1)
+ return -1;
+ return 1;
+}
+
/* Dump frontends metrics (prefixed by "haproxy_frontend_"). It returns 1 on success,
* 0 if <htx> is full and -1 in case of any error. */
static int promex_dump_front_metrics(struct appctx *appctx, struct htx *htx)
@@ -648,6 +664,9 @@
size_t max = htx_get_max_blksz(htx, channel_htx_recv_max(chn, htx));
struct field *stats = stat_l[STATS_DOMAIN_PROXY];
int ret = 1;
+ enum promex_front_state state;
+ struct ist metric_label;
+ int i;
for (;appctx->st2 < ST_F_TOTAL_FIELDS; appctx->st2++) {
if (!(promex_st_metrics[appctx->st2].flags & appctx->ctx.stats.flags))
@@ -665,8 +684,16 @@
switch (appctx->st2) {
case ST_F_STATUS:
- val = mkf_u32(FO_STATUS, !px->disabled);
- break;
+ state = !px->disabled;
+ for (i = 0; i < PROMEX_FRONT_STATE_COUNT; i++) {
+ val = mkf_u32(FO_STATUS, state == i);
+ if (promex_state_label(&metric_label, promex_front_st[i]) == -1)
+ goto full;
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
+ &val, metric_label, &out, max))
+ goto full;
+ }
+ goto next_px;
case ST_F_REQ_RATE_MAX:
case ST_F_REQ_TOT:
case ST_F_HRSP_1XX:
@@ -696,7 +723,8 @@
val = stats[appctx->st2];
}
- if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2], &val, &out, max))
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
+ &val, IST_NULL, &out, max))
goto full;
next_px:
appctx->ctx.stats.obj1 = px->next;
@@ -730,6 +758,9 @@
struct field *stats = stat_l[STATS_DOMAIN_PROXY];
int ret = 1;
double secs;
+ enum promex_back_state state;
+ struct ist metric_label;
+ int i;
for (;appctx->st2 < ST_F_TOTAL_FIELDS; appctx->st2++) {
if (!(promex_st_metrics[appctx->st2].flags & appctx->ctx.stats.flags))
@@ -747,8 +778,16 @@
switch (appctx->st2) {
case ST_F_STATUS:
- val = mkf_u32(FO_STATUS, (px->lbprm.tot_weight > 0 || !px->srv) ? 1 : 0);
- break;
+ state = ((px->lbprm.tot_weight > 0 || !px->srv) ? 1 : 0);
+ for (i = 0; i < PROMEX_BACK_STATE_COUNT; i++) {
+ val = mkf_u32(FO_STATUS, state == i);
+ if (promex_state_label(&metric_label, promex_back_st[i]) == -1)
+ goto full;
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
+ &val, metric_label, &out, max))
+ goto full;
+ }
+ goto next_px;
case ST_F_QTIME:
secs = (double)swrate_avg(px->be_counters.q_time, TIME_STATS_SAMPLES) / 1000.0;
val = mkf_flt(FN_AVG, secs);
@@ -809,7 +848,7 @@
}
if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
- &val, &out, max))
+ &val, IST_NULL, &out, max))
goto full;
next_px:
appctx->ctx.stats.obj1 = px->next;
@@ -844,6 +883,9 @@
struct field *stats = stat_l[STATS_DOMAIN_PROXY];
int ret = 1;
double secs;
+ enum promex_srv_state state;
+ struct ist metric_label;
+ int i;
for (;appctx->st2 < ST_F_TOTAL_FIELDS; appctx->st2++) {
if (!(promex_st_metrics[appctx->st2].flags & appctx->ctx.stats.flags))
@@ -867,8 +909,16 @@
switch (appctx->st2) {
case ST_F_STATUS:
- val = mkf_u32(FO_STATUS, promex_srv_status(sv));
- break;
+ state = promex_srv_status(sv);
+ for (i = 0; i < PROMEX_SRV_STATE_COUNT; i++) {
+ val = mkf_u32(FO_STATUS, state == i);
+ if (promex_state_label(&metric_label, promex_srv_st[i]) == -1)
+ goto full;
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
+ &val, metric_label, &out, max))
+ goto full;
+ }
+ goto next_sv;
case ST_F_QTIME:
secs = (double)swrate_avg(sv->counters.q_time, TIME_STATS_SAMPLES) / 1000.0;
val = mkf_flt(FN_AVG, secs);
@@ -938,7 +988,8 @@
val = stats[appctx->st2];
}
- if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2], &val, &out, max))
+ if (!promex_dump_metric(appctx, htx, prefix, &promex_st_metrics[appctx->st2],
+ &val, IST_NULL, &out, max))
goto full;
next_sv:
appctx->ctx.stats.obj2 = sv->next;