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diff --git a/src/stats/stats-settings.h b/src/stats/stats-settings.h
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+#ifndef STATS_SETTINGS_H
+#define STATS_SETTINGS_H
+
+#define STATS_METRIC_SETTINGS_DEFAULT_EXPORTER_INCLUDE \
+	"name hostname timestamps categories fields"
+
+/* <settings checks> */
+/*
+ * We allow a selection of a timestamp format.
+ *
+ * The 'time-unix' format generates a number with the number of seconds
+ * since 1970-01-01 00:00 UTC.
+ *
+ * The 'time-rfc3339' format uses the YYYY-MM-DDTHH:MM:SS.uuuuuuZ format as
+ * defined by RFC 3339.
+ *
+ * The special native format (not explicitly selectable in the config, but
+ * default if no time-* token is used) uses the format's native timestamp
+ * format.  Note that not all formats have a timestamp data format.
+ *
+ * The native format and the rules below try to address the question: can a
+ * parser that doesn't have any knowledge of fields' values' types losslessly
+ * reconstruct the fields?
+ *
+ * For example, JSON only has strings and numbers, so it cannot represent a
+ * timestamp in a "context-free lossless" way.  Therefore, when making a
+ * JSON blob, we need to decide which way to serialize timestamps.  No
+ * matter how we do it, we incur some loss.  If a decoder sees 1557232304 in
+ * a field, it cannot be certain if the field is an integer that just
+ * happens to be a reasonable timestamp, or if it actually is a timestamp.
+ * Same goes with RFC3339 - it could just be that the user supplied a string
+ * that looks like a timestamp, and that string made it into an event field.
+ *
+ * Other common serialization formats, such as CBOR, have a lossless way of
+ * encoding timestamps.
+ *
+ * Note that there are two concepts at play: native and default.
+ *
+ * The rules for how the format's timestamp formats are used:
+ *
+ * 1. The default time format is the native format.
+ * 2. The native time format may or may not exist for a given format (e.g.,
+ *    in JSON)
+ * 3. If the native format doesn't exist and no time format was specified in
+ *    the config, it is a config error.
+ *
+ * We went with these rules because:
+ *
+ * 1. It prevents type information loss by default.
+ * 2. It completely isolates the policy from the algorithm.
+ * 3. It defers the decision whether each format without a native timestamp
+ *    type should have a default acting as native until after we've had some
+ *    operational experience.
+ * 4. A future decision to add a default (via 3. point) will be 100% compatible.
+ */
+enum event_exporter_time_fmt {
+	EVENT_EXPORTER_TIME_FMT_NATIVE = 0,
+	EVENT_EXPORTER_TIME_FMT_UNIX,
+	EVENT_EXPORTER_TIME_FMT_RFC3339,
+};
+/* </settings checks> */
+
+struct stats_exporter_settings {
+	const char *name;
+	const char *transport;
+	const char *transport_args;
+	unsigned int transport_timeout;
+	const char *format;
+	const char *format_args;
+
+	/* parsed values */
+	enum event_exporter_time_fmt parsed_time_format;
+};
+
+/* <settings checks> */
+enum stats_metric_group_by_func {
+	STATS_METRIC_GROUPBY_DISCRETE = 0,
+	STATS_METRIC_GROUPBY_QUANTIZED,
+};
+
+/*
+ * A range covering a stats bucket.  The the interval is half closed - the
+ * minimum is excluded and the maximum is included.  In other words: (min, max].
+ * Because we don't have a +Inf and -Inf, we use INTMAX_MIN and INTMAX_MAX
+ * respectively.
+ */
+struct stats_metric_settings_bucket_range {
+	intmax_t min;
+	intmax_t max;
+};
+
+struct stats_metric_settings_group_by {
+	const char *field;
+	enum stats_metric_group_by_func func;
+	unsigned int num_ranges;
+	struct stats_metric_settings_bucket_range *ranges;
+};
+/* </settings checks> */
+
+struct stats_metric_settings {
+	const char *metric_name;
+	const char *description;
+	const char *fields;
+	const char *group_by;
+	const char *filter;
+
+	ARRAY(struct stats_metric_settings_group_by) parsed_group_by;
+	struct event_filter *parsed_filter;
+
+	/* exporter related fields */
+	const char *exporter;
+	const char *exporter_include;
+};
+
+struct stats_settings {
+	const char *stats_http_rawlog_dir;
+
+	ARRAY(struct stats_exporter_settings *) exporters;
+	ARRAY(struct stats_metric_settings *) metrics;
+};
+
+extern const struct setting_parser_info stats_setting_parser_info;
+extern const struct setting_parser_info stats_metric_setting_parser_info;
+
+#endif