#include <microhttpd.h>
#ifndef PROMETHEUS_DEFAULT_STALENESS_DELTA
-#define PROMETHEUS_DEFAULT_STALENESS_DELTA TIME_T_TO_CDTIME_T(300)
+#define PROMETHEUS_DEFAULT_STALENESS_DELTA TIME_T_TO_CDTIME_T_STATIC(300)
#endif
#define VARINT_UINT32_BYTES 5
pthread_mutex_unlock(&metrics_lock);
}
+static char const *escape_label_value(char *buffer, size_t buffer_size,
+ char const *value) {
+ /* shortcut for values that don't need escaping. */
+ if (strpbrk(value, "\n\"\\") == NULL)
+ return value;
+
+ size_t value_len = strlen(value);
+ size_t buffer_len = 0;
+
+ for (size_t i = 0; i < value_len; i++) {
+ switch (value[i]) {
+ case '\n':
+ case '"':
+ case '\\':
+ if ((buffer_size - buffer_len) < 3) {
+ break;
+ }
+ buffer[buffer_len] = '\\';
+ buffer[buffer_len + 1] = (value[i] == '\n') ? 'n' : value[i];
+ buffer_len += 2;
+ break;
+
+ default:
+ if ((buffer_size - buffer_len) < 2) {
+ break;
+ }
+ buffer[buffer_len] = value[i];
+ buffer_len++;
+ break;
+ }
+ }
+
+ assert(buffer_len < buffer_size);
+ buffer[buffer_len] = 0;
+ return buffer;
+}
+
/* format_labels formats a metric's labels in Prometheus-compatible format. This
* format looks like this:
*
assert(m->n_label >= 1);
assert(m->n_label <= 3);
-#define LABEL_BUFFER_SIZE (2 * DATA_MAX_NAME_LEN + 4)
+#define LABEL_KEY_SIZE DATA_MAX_NAME_LEN
+#define LABEL_VALUE_SIZE (2 * DATA_MAX_NAME_LEN - 1)
+#define LABEL_BUFFER_SIZE (LABEL_KEY_SIZE + LABEL_VALUE_SIZE + 4)
char *labels[3] = {
(char[LABEL_BUFFER_SIZE]){0}, (char[LABEL_BUFFER_SIZE]){0},
(char[LABEL_BUFFER_SIZE]){0},
};
- for (size_t i = 0; i < m->n_label; i++)
- ssnprintf(labels[i], LABEL_BUFFER_SIZE, "%s=\"%s\"", m->label[i]->name,
- m->label[i]->value);
+ /* N.B.: the label *names* are hard-coded by this plugin and therefore we
+ * know that they are sane. */
+ for (size_t i = 0; i < m->n_label; i++) {
+ char value[LABEL_VALUE_SIZE];
+ snprintf(labels[i], LABEL_BUFFER_SIZE, "%s=\"%s\"", m->label[i]->name,
+ escape_label_value(value, sizeof(value), m->label[i]->value));
+ }
strjoin(buffer, buffer_size, labels, m->n_label, ",");
return buffer;
while (c_avl_iterator_next(iter, (void *)&unused_name, (void *)&fam) == 0) {
char line[1024]; /* 4x DATA_MAX_NAME_LEN? */
- ssnprintf(line, sizeof(line), "# HELP %s %s\n", fam->name, fam->help);
+ snprintf(line, sizeof(line), "# HELP %s %s\n", fam->name, fam->help);
buffer->append(buffer, strlen(line), (uint8_t *)line);
- ssnprintf(line, sizeof(line), "# TYPE %s %s\n", fam->name,
- (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
- ? "gauge"
- : "counter");
+ snprintf(line, sizeof(line), "# TYPE %s %s\n", fam->name,
+ (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
+ ? "gauge"
+ : "counter");
buffer->append(buffer, strlen(line), (uint8_t *)line);
for (size_t i = 0; i < fam->n_metric; i++) {
char timestamp_ms[24] = "";
if (m->has_timestamp_ms)
- ssnprintf(timestamp_ms, sizeof(timestamp_ms), " %" PRIi64,
- m->timestamp_ms);
+ snprintf(timestamp_ms, sizeof(timestamp_ms), " %" PRIi64,
+ m->timestamp_ms);
if (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__GAUGE)
- ssnprintf(line, sizeof(line), "%s{%s} " GAUGE_FORMAT "%s\n", fam->name,
- format_labels(labels, sizeof(labels), m), m->gauge->value,
- timestamp_ms);
+ snprintf(line, sizeof(line), "%s{%s} " GAUGE_FORMAT "%s\n", fam->name,
+ format_labels(labels, sizeof(labels), m), m->gauge->value,
+ timestamp_ms);
else /* if (fam->type == IO__PROMETHEUS__CLIENT__METRIC_TYPE__COUNTER) */
- ssnprintf(line, sizeof(line), "%s{%s} %.0f%s\n", fam->name,
- format_labels(labels, sizeof(labels), m), m->counter->value,
- timestamp_ms);
+ snprintf(line, sizeof(line), "%s{%s} %.0f%s\n", fam->name,
+ format_labels(labels, sizeof(labels), m), m->counter->value,
+ timestamp_ms);
buffer->append(buffer, strlen(line), (uint8_t *)line);
}
c_avl_iterator_destroy(iter);
char server[1024];
- ssnprintf(server, sizeof(server), "\n# collectd/write_prometheus %s at %s\n",
- PACKAGE_VERSION, hostname_g);
+ snprintf(server, sizeof(server), "\n# collectd/write_prometheus %s at %s\n",
+ PACKAGE_VERSION, hostname_g);
buffer->append(buffer, strlen(server), (uint8_t *)server);
pthread_mutex_unlock(&metrics_lock);
else
format_text(buffer);
+#if defined(MHD_VERSION) && MHD_VERSION >= 0x00090500
+ struct MHD_Response *res = MHD_create_response_from_buffer(
+ simple.len, simple.data, MHD_RESPMEM_MUST_COPY);
+#else
struct MHD_Response *res = MHD_create_response_from_data(
simple.len, simple.data, /* must_free = */ 0, /* must_copy = */ 1);
+#endif
MHD_add_response_header(res, MHD_HTTP_HEADER_CONTENT_TYPE,
want_proto ? CONTENT_TYPE_PROTO : CONTENT_TYPE_TEXT);
return 1;
/* Prometheus does not care about the order of labels. All labels in this
- * plugin are created by metric_add_labels(), though, and therefore always
+ * plugin are created by METRIC_ADD_LABELS(), though, and therefore always
* appear in the same order. We take advantage of this and simplify the check
- * by making sure all labels are the same in each position. */
+ * by making sure all labels are the same in each position.
+ *
+ * We also only need to check the label values, because the label names are
+ * the same for all metrics in a metric family.
+ *
+ * 3 labels:
+ * [0] $plugin="$plugin_instance" => $plugin is the same within a family
+ * [1] type="$type_instance" => "type" is a static string
+ * [2] instance="$host" => "instance" is a static string
+ *
+ * 2 labels, variant 1:
+ * [0] $plugin="$plugin_instance" => $plugin is the same within a family
+ * [1] instance="$host" => "instance" is a static string
+ *
+ * 2 labels, variant 2:
+ * [0] $plugin="$type_instance" => $plugin is the same within a family
+ * [1] instance="$host" => "instance" is a static string
+ *
+ * 1 label:
+ * [1] instance="$host" => "instance" is a static string
+ */
for (size_t i = 0; i < m_a->n_label; i++) {
- int status = strcmp(m_a->label[i]->name, m_b->label[i]->name);
+ int status = strcmp(m_a->label[i]->value, m_b->label[i]->value);
if (status != 0)
return status;
- status = strcmp(m_a->label[i]->value, m_b->label[i]->value);
- if (status != 0)
- return status;
+#if COLLECT_DEBUG
+ assert(strcmp(m_a->label[i]->name, m_b->label[i]->name) == 0);
+#endif
}
return 0;
((fam->n_metric - 1) - i) * sizeof(fam->metric[i]));
fam->n_metric--;
+ if (fam->n_metric == 0) {
+ sfree(fam->metric);
+ return 0;
+ }
+
Io__Prometheus__Client__Metric **tmp =
realloc(fam->metric, fam->n_metric * sizeof(*fam->metric));
- if ((tmp != NULL) || (fam->n_metric == 0))
+ if (tmp != NULL)
fam->metric = tmp;
return 0;
msg->name = name;
char help[1024];
- ssnprintf(
+ snprintf(
help, sizeof(help),
"write_prometheus plugin: '%s' Type: '%s', Dstype: '%s', Dsname: '%s'",
vl->plugin, vl->type, DS_TYPE_TO_STRING(ds->ds[ds_index].type),
/* metric_family_get looks up the matching metric family, allocating it if
* necessary. */
static Io__Prometheus__Client__MetricFamily *
-metric_family_get(data_set_t const *ds, value_list_t const *vl,
- size_t ds_index) {
+metric_family_get(data_set_t const *ds, value_list_t const *vl, size_t ds_index,
+ _Bool allocate) {
char *name = metric_family_name(ds, vl, ds_index);
if (name == NULL) {
ERROR("write_prometheus plugin: Allocating metric family name failed.");
return fam;
}
+ if (!allocate) {
+ sfree(name);
+ return NULL;
+ }
+
fam = metric_family_create(name, ds, vl, ds_index);
if (fam == NULL) {
ERROR("write_prometheus plugin: Allocating metric family failed.");
pthread_mutex_lock(&metrics_lock);
for (size_t i = 0; i < ds->ds_num; i++) {
- Io__Prometheus__Client__MetricFamily *fam = metric_family_get(ds, vl, i);
+ Io__Prometheus__Client__MetricFamily *fam =
+ metric_family_get(ds, vl, i, /* allocate = */ 1);
if (fam == NULL)
continue;
pthread_mutex_lock(&metrics_lock);
for (size_t i = 0; i < ds->ds_num; i++) {
- Io__Prometheus__Client__MetricFamily *fam = metric_family_get(ds, vl, i);
+ Io__Prometheus__Client__MetricFamily *fam =
+ metric_family_get(ds, vl, i, /* allocate = */ 0);
if (fam == NULL)
continue;
ERROR("write_prometheus plugin: Deleting a metric in family \"%s\" "
"failed with status %d",
fam->name, status);
+
continue;
}
/* user data = */ NULL);
plugin_register_shutdown("write_prometheus", prom_shutdown);
}
-
-/* vim: set sw=2 sts=2 et fdm=marker : */
projects / collectd.git / blobdiff