1 files changed, 249 insertions, 0 deletions
diff --git a/src/stats/event-exporter-fmt-json.c b/src/stats/event-exporter-fmt-json.c
new file mode 100644
index 0000000..25c6116
--- /dev/null
+++ b/src/stats/event-exporter-fmt-json.c
@@ -0,0 +1,249 @@
+/* Copyright (c) 2019 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "ioloop.h"
+#include "array.h"
+#include "lib-event-private.h"
+#include "event-exporter.h"
+#include "str.h"
+#include "json-parser.h"
+#include "hostpid.h"
+
+static void append_str(string_t *dest, const char *str)
+{
+	str_append_c(dest, '"');
+	json_append_escaped(dest, str);
+	str_append_c(dest, '"');
+}
+
+static void append_str_max_len(string_t *dest, const char *str,
+			       const struct metric_export_info *info)
+{
+	str_append_c(dest, '"');
+	if (info->exporter->format_max_field_len == 0)
+		json_append_escaped(dest, str);
+	else {
+		size_t len = strlen(str);
+		json_append_escaped_data(dest, (const unsigned char *)str,
+			I_MIN(len, info->exporter->format_max_field_len));
+		if (len > info->exporter->format_max_field_len)
+			str_append(dest, "...");
+	}
+	str_append_c(dest, '"');
+}
+
+static void
+append_strlist(string_t *dest, const ARRAY_TYPE(const_string) *strlist,
+	       const struct metric_export_info *info)
+{
+	const char *value;
+	bool first = TRUE;
+
+	str_append_c(dest, '[');
+	array_foreach_elem(strlist, value) {
+		if (first)
+			first = FALSE;
+		else
+			str_append_c(dest, ',');
+		append_str_max_len(dest, value, info);
+	}
+	str_append_c(dest, ']');
+}
+
+static void append_int(string_t *dest, intmax_t val)
+{
+	str_printfa(dest, "%jd", val);
+}
+
+static void append_time(string_t *dest, const struct timeval *time,
+			enum event_exporter_time_fmt fmt)
+{
+	switch (fmt) {
+	case EVENT_EXPORTER_TIME_FMT_NATIVE:
+		i_panic("JSON does not have a native date/time type");
+	case EVENT_EXPORTER_TIME_FMT_UNIX:
+		event_export_helper_fmt_unix_time(dest, time);
+		break;
+	case EVENT_EXPORTER_TIME_FMT_RFC3339:
+		str_append_c(dest, '"');
+		event_export_helper_fmt_rfc3339_time(dest, time);
+		str_append_c(dest, '"');
+		break;
+	}
+}
+
+static void append_field_value(string_t *dest, const struct event_field *field,
+			       const struct metric_export_info *info)
+{
+	switch (field->value_type) {
+	case EVENT_FIELD_VALUE_TYPE_STR:
+		append_str_max_len(dest, field->value.str, info);
+		break;
+	case EVENT_FIELD_VALUE_TYPE_INTMAX:
+		append_int(dest, field->value.intmax);
+		break;
+	case EVENT_FIELD_VALUE_TYPE_TIMEVAL:
+		append_time(dest, &field->value.timeval,
+			    info->exporter->time_format);
+		break;
+	case EVENT_FIELD_VALUE_TYPE_STRLIST:
+		append_strlist(dest, &field->value.strlist, info);
+		break;
+	}
+}
+
+static void json_export_name(string_t *dest, struct event *event,
+			     const struct metric_export_info *info)
+{
+	if ((info->include & EVENT_EXPORTER_INCL_NAME) == 0)
+		return;
+
+	append_str(dest, "event");
+	str_append_c(dest, ':');
+	append_str(dest, event->sending_name);
+	str_append_c(dest, ',');
+}
+
+static void json_export_hostname(string_t *dest,
+				 const struct metric_export_info *info)
+{
+	if ((info->include & EVENT_EXPORTER_INCL_HOSTNAME) == 0)
+		return;
+
+	append_str(dest, "hostname");
+	str_append_c(dest, ':');
+	append_str(dest, my_hostname);
+	str_append_c(dest, ',');
+}
+
+static void json_export_timestamps(string_t *dest, struct event *event,
+				   const struct metric_export_info *info)
+{
+	if ((info->include & EVENT_EXPORTER_INCL_TIMESTAMPS) == 0)
+		return;
+
+	append_str(dest, "start_time");
+	str_append_c(dest, ':');
+	append_time(dest, &event->tv_created, info->exporter->time_format);
+	str_append_c(dest, ',');
+
+	append_str(dest, "end_time");
+	str_append_c(dest, ':');
+	append_time(dest, &ioloop_timeval, info->exporter->time_format);
+	str_append_c(dest, ',');
+}
+
+static void json_export_categories(string_t *dest, struct event *event,
+				   const struct metric_export_info *info)
+{
+	struct event_category *const *cats;
+	unsigned int count;
+
+	if ((info->include & EVENT_EXPORTER_INCL_CATEGORIES) == 0)
+		return;
+
+	append_str(dest, "categories");
+	str_append(dest, ":[");
+
+	cats = event_get_categories(event, &count);
+	event_export_helper_fmt_categories(dest, cats, count,
+					   append_str, ",");
+
+	str_append(dest, "],");
+}
+
+static void json_export_fields(string_t *dest, struct event *event,
+			       const struct metric_export_info *info,
+			       const unsigned int fields_count,
+			       const struct metric_field *fields)
+{
+	bool appended = FALSE;
+
+	if ((info->include & EVENT_EXPORTER_INCL_FIELDS) == 0)
+		return;
+
+	append_str(dest, "fields");
+	str_append(dest, ":{");
+
+	if (fields_count == 0) {
+		/* include all fields */
+		const struct event_field *fields;
+		unsigned int count;
+
+		fields = event_get_fields(event, &count);
+
+		for (unsigned int i = 0; i < count; i++) {
+			const struct event_field *field = &fields[i];
+
+			append_str(dest, field->key);
+			str_append_c(dest, ':');
+			append_field_value(dest, field, info);
+			str_append_c(dest, ',');
+
+			appended = TRUE;
+		}
+	} else {
+		for (unsigned int i = 0; i < fields_count; i++) {
+			const char *name = fields[i].field_key;
+			const struct event_field *field;
+
+			field = event_find_field_recursive(event, name);
+			if (field == NULL)
+				continue; /* doesn't exist, skip it */
+
+			append_str(dest, name);
+			str_append_c(dest, ':');
+			append_field_value(dest, field, info);
+			str_append_c(dest, ',');
+
+			appended = TRUE;
+		}
+	}
+
+	/* remove trailing comma */
+	if (appended)
+		str_truncate(dest, str_len(dest) - 1);
+
+	str_append(dest, "},");
+}
+
+/*
+ * Serialize the event as:
+ *
+ * {
+ *	"name": <event name>,
+ *	"hostname": <hostname>,
+ *	"start_time": <event creation timestamp>,
+ *	"end_time": <event export timestamp>,
+ *	"categories": [ <categories>, ... ],
+ *	"fields": {
+ *		<name>: <value>,
+ *		...
+ *	}
+ * }
+ *
+ */
+void event_export_fmt_json(const struct metric *metric,
+			   struct event *event, buffer_t *dest)
+{
+	const struct metric_export_info *info = &metric->export_info;
+
+	if (info->include == EVENT_EXPORTER_INCL_NONE) {
+		str_append(dest, "{}");
+		return;
+	}
+
+	str_append_c(dest, '{');
+
+	json_export_name(dest, event, info);
+	json_export_hostname(dest, info);
+	json_export_timestamps(dest, event, info);
+	json_export_categories(dest, event, info);
+	json_export_fields(dest, event, info, metric->fields_count,
+			   metric->fields);
+
+	/* remove trailing comma */
+	str_truncate(dest, str_len(dest) - 1);
+
+	str_append_c(dest, '}');
+}