--- /dev/null
+/* Copyright (c) 2019 Dovecot authors, see the included COPYING file */
+
+#include "stats-common.h"
+#include "dovecot-version.h"
+#include "str.h"
+#include "array.h"
+#include "ioloop.h"
+#include "stats-dist.h"
+#include "http-server.h"
+#include "client-http.h"
+#include "stats-settings.h"
+#include "stats-metrics.h"
+#include "stats-service-private.h"
+
+#define OPENMETRICS_CONTENT_VERSION "0.0.4"
+
+#ifdef DOVECOT_REVISION
+#define OPENMETRICS_BUILD_INFO \
+ "version=\""DOVECOT_VERSION"\"," \
+ "revision=\""DOVECOT_REVISION"\""
+#else
+#define OPENMETRICS_BUILD_INFO \
+ "version=\""DOVECOT_VERSION"\""
+#endif
+
+/* https://prometheus.io/docs/concepts/data_model/#metric-names-and-labels:
+
+ Every time series is uniquely identified by its metric name and optional
+ key-value pairs called labels.
+
+ The metric name specifies the general feature of a system that is measured
+ (e.g. http_requests_total - the total number of HTTP requests received). It
+ may contain ASCII letters and digits, as well as underscores and colons. It
+ must match the regex [a-zA-Z_:][a-zA-Z0-9_:]*.
+ */
+
+static bool openmetrics_check_name(const char *name)
+{
+ const unsigned char *p, *pend;
+
+ p = (const unsigned char *)name;
+ pend = p + strlen(name);
+
+ if (p == pend)
+ return FALSE;
+
+ if (!(*p >= 'a' && *p <= 'z') && !(*p >= 'A' && *p <= 'Z') &&
+ *p != '_' && *p != ':')
+ return FALSE;
+ p++;
+ while (p < pend) {
+ if (!(*p >= 'a' && *p <= 'z') && !(*p >= 'A' && *p <= 'Z') &&
+ !(*p >= '0' && *p <= '9') && *p != '_' && *p != ':')
+ return FALSE;
+ p++;
+ }
+ return TRUE;
+}
+
+static bool openmetrics_check_metric(const struct metric *metric)
+{
+ const char *const *filters;
+ unsigned int i, count;
+
+ if (!openmetrics_check_name(metric->name))
+ return FALSE;
+
+ if (!array_is_created(&metric->set->filter))
+ return TRUE;
+
+ filters = array_get(&metric->set->filter, &count);
+ if (count == 0)
+ return TRUE;
+ i_assert(count % 2 == 0);
+
+ count /= 2;
+ for (i = 1; i < count; i++) {
+ if (!openmetrics_check_name(filters[i * 2]))
+ return FALSE;
+ }
+ return TRUE;
+}
+
+/* https://prometheus.io/docs/prometheus/latest/querying/basics/#literals:
+
+ PromQL follows the same escaping rules as Go. In single or double quotes a
+ backslash begins an escape sequence, which may be followed by a, b, f, n, r,
+ t, v or \. Specific characters can be provided using octal (\nnn) or
+ hexadecimal (\xnn, \unnnn and \Unnnnnnnn).
+
+ https://golang.org/ref/spec#String_literals:
+
+ Interpreted string literals are character sequences between double quotes, as
+ in "bar". Within the quotes, any character may appear except newline and
+ unescaped double quote. The text between the quotes forms the value of the
+ literal, with backslash escapes interpreted as they are in rune literals
+ (except that \' is illegal and \" is legal), with the same restrictions.
+
+ -> Cannot use strescape.h, since \' is illegal.
+ */
+static void openmetrics_escape_string(string_t *dest, const char *value)
+{
+ const unsigned char *pstart, *p, *pend;
+
+ pstart = p = (const unsigned char *)value;
+ pend = pstart + strlen(value);
+
+ /* See if we need to quote it */
+ for (; p < pend; p++) {
+ if (*p == '\n' || *p == '"')
+ break;
+ }
+
+ /* Quote */
+ str_append_data(dest, pstart, (size_t)(p - pstart));
+
+ for (; p < pend; p++) {
+ if (*p == '\n' || *p == '"')
+ str_append_c(dest, '\\');
+ str_append_data(dest, p, 1);
+ }
+}
+
+static void
+openmetrics_export_metric_labels(string_t *out, const struct metric *metric)
+{
+ const char *const *filters;
+ unsigned int i, count;
+
+ if (!array_is_created(&metric->set->filter))
+ return;
+
+ filters = array_get(&metric->set->filter, &count);
+ if (count == 0)
+ return;
+ i_assert(count % 2 == 0);
+
+ str_append_c(out, '{');
+
+ str_append(out, filters[0]);
+ str_append(out, "=\"");
+ openmetrics_escape_string(out, filters[1]);
+ str_append_c(out, '"');
+
+ count /= 2;
+ for (i = 1; i < count; i++) {
+ str_append_c(out, ',');
+ str_append(out, filters[i * 2]);
+ str_append(out, "=\"");
+ openmetrics_escape_string(out, filters[i * 2 + 1]);
+ str_append_c(out, '"');
+ }
+
+ str_append_c(out, '}');
+}
+
+static void
+openmetrics_export_metric(string_t *out, const struct metric *metric,
+ int64_t timestamp)
+{
+ if (!openmetrics_check_metric(metric))
+ return;
+
+ /* Description */
+ str_append(out, "# HELP dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_count Total number");
+ if (*metric->set->description != '\0') {
+ str_append(out, " of ");
+ str_append(out, metric->set->description);
+ }
+ str_append_c(out, '\n');
+ /* Type */
+ str_append(out, "# TYPE dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_count counter\n");
+ /* Metric name */
+ str_append(out, "dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_count");
+ /* Labels */
+ openmetrics_export_metric_labels(out, metric);
+ /* Value */
+ str_printfa(out, " %u %"PRId64"\n\n",
+ stats_dist_get_count(metric->duration_stats), timestamp);
+
+ /* Description */
+ str_append(out, "# HELP dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_duration_usecs_sum Duration");
+ if (*metric->set->description != '\0') {
+ str_append(out, " of ");
+ str_append(out, metric->set->description);
+ }
+ str_append_c(out, '\n');
+ /* Type */
+ str_append(out, "# TYPE dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_duration_usecs_sum counter\n");
+ /* Metric name*/
+ str_append(out, "dovecot_");
+ str_append(out, metric->name);
+ str_append(out, "_duration_usecs_sum");
+ /* Labels */
+ openmetrics_export_metric_labels(out, metric);
+ /* Value */
+ str_printfa(out, " %"PRIu64" %"PRId64"\n",
+ stats_dist_get_sum(metric->duration_stats),
+ timestamp);
+}
+
+static void
+openmetrics_export(struct http_server_response *resp)
+{
+ struct stats_metrics_iter *iter;
+ const struct metric *metric;
+ string_t *out = t_str_new(2048);
+ int64_t timestamp;
+
+ i_assert(ioloop_timeval.tv_usec < 1000000);
+ timestamp = ((int64_t)ioloop_timeval.tv_sec * 1000 +
+ (int64_t)ioloop_timeval.tv_usec / 1000);
+
+ i_assert(stats_startup_time <= ioloop_time);
+ str_append(out, "# HELP dovecot_stats_uptime_seconds "
+ "Dovecot stats service uptime\n");
+ str_append(out, "# TYPE dovecot_stats_uptime_seconds counter\n");
+ str_printfa(out, "dovecot_stats_uptime_seconds %"PRId64" %"PRId64"\n\n",
+ (int64_t)(ioloop_time - stats_startup_time), timestamp);
+
+ str_append(out, "# HELP dovecot_build_info "
+ "Dovecot build information\n");
+ str_append(out, "# TYPE dovecot_build_info untyped\n");
+ str_printfa(out, "dovecot_build_info{"OPENMETRICS_BUILD_INFO"} "
+ "1 %"PRId64"\n", timestamp);
+
+ iter = stats_metrics_iterate_init(stats_metrics);
+ while ((metric = stats_metrics_iterate(iter)) != NULL) {
+ /* Empty line */
+ str_append_c(out, '\n');
+
+ openmetrics_export_metric(out, metric, timestamp);
+ }
+ stats_metrics_iterate_deinit(&iter);
+
+ http_server_response_set_payload_data(
+ resp, str_data(out), str_len(out));
+}
+
+static void
+stats_service_openmetrics_request(void *context ATTR_UNUSED,
+ struct http_server_request *req,
+ const char *sub_path)
+{
+ const struct http_request *hreq = http_server_request_get(req);
+ struct http_server_response *resp;
+
+ if (strcmp(hreq->method, "OPTIONS") == 0) {
+ resp = http_server_response_create(req, 200, "OK");
+ http_server_response_add_header(resp, "Allow", "GET");
+ http_server_response_submit(resp);
+ return;
+ }
+ if (strcmp(hreq->method, "GET") != 0) {
+ http_server_request_fail_bad_method(req, "GET");
+ return;
+ }
+ if (*sub_path != '\0') {
+ http_server_request_fail(req, 404, "Not Found");
+ return;
+ }
+
+ resp = http_server_response_create(req, 200, "OK");
+ http_server_response_add_header(
+ resp, "Content-Type", "text/plain; "
+ "version="OPENMETRICS_CONTENT_VERSION"; "
+ "charset=utf-8");
+
+ openmetrics_export(resp);
+
+ http_server_response_submit(resp);
+}
+
+void stats_service_openmetrics_init(void)
+{
+ struct stats_metrics_iter *iter;
+ const struct metric *metric;
+
+ iter = stats_metrics_iterate_init(stats_metrics);
+ while ((metric = stats_metrics_iterate(iter)) != NULL) {
+ if (!openmetrics_check_metric(metric)) {
+ i_warning(
+ "stats: openmetrics: "
+ "Metric `%s' is not valid for OpenMetrics"
+ "(invalid metric or label name; skipped)",
+ metric->name);
+ }
+ }
+ stats_metrics_iterate_deinit(&iter);
+
+ stats_http_resource_add("/metrics", "OpenMetrics",
+ stats_service_openmetrics_request, NULL);
+}
projects / thirdparty / dovecot / core.git / commitdiff
