out_forward: add support to forward metrics

Signed-off-by: Eduardo Silva <[email protected]>

plugins/out_forward/forward.c

@@ -1344,4 +1344,7 @@ struct flb_output_plugin out_forward_plugin = {
 
  /* Flags */
  .flags = FLB_OUTPUT_NET | FLB_IO_OPT_TLS,
+
+ /* Event types */
+ .event_type = FLB_OUTPUT_LOGS | FLB_OUTPUT_METRICS
 };

plugins/out_forward/forward_format.c

@@ -253,6 +253,48 @@ static int flb_forward_format_message_mode(struct flb_forward *ctx,
 }
 #endif
 
+static int flb_forward_format_metrics_mode(struct flb_forward *ctx,
+ struct flb_forward_config *fc,
+ struct flb_forward_flush *ff,
+ const char *tag, int tag_len,
+ const void *data, size_t bytes,
+ void **out_buf, size_t *out_size)
+{
+ msgpack_packer mp_pck;
+ msgpack_sbuffer mp_sbuf;
+ struct flb_time tm;
+
+ msgpack_sbuffer_init(&mp_sbuf);
+ msgpack_packer_init(&mp_pck, &mp_sbuf, msgpack_sbuffer_write);
+
+ msgpack_pack_array(&mp_pck, 3);
+
+ if (fc->tag) {
+ msgpack_pack_str(&mp_pck, flb_sds_len(fc->tag));
+ msgpack_pack_str_body(&mp_pck, fc->tag, flb_sds_len(fc->tag));
+ }
+ else {
+ msgpack_pack_str(&mp_pck, tag_len);
+ msgpack_pack_str_body(&mp_pck, tag, tag_len);
+ }
+
+ /* timestamp */
+ flb_time_get(&tm);
+ flb_time_append_to_msgpack(&tm, &mp_pck, 0);
+
+ /* metrics */
+ msgpack_pack_map(&mp_pck, 1);
+ msgpack_pack_str(&mp_pck, 8);
+ msgpack_pack_str_body(&mp_pck, "cmetrics", 8);
+ msgpack_pack_bin(&mp_pck, bytes);
+ msgpack_pack_bin_body(&mp_pck, data, bytes);
+
+ *out_buf = mp_sbuf.data;
+ *out_size = mp_sbuf.size;
+
+ return 0;
+}
+
 /*
  * Forward Protocol: Forward Mode
  * ------------------------------
@@ -399,6 +441,19 @@ int flb_forward_format(struct flb_config *config,
  return -1;
  }
 
+ /* metric handling */
+ if (flb_input_event_type_is_metric(ins)) {
+ ret = flb_forward_format_metrics_mode(ctx, fc, ff,
+ tag, tag_len,
+ data, bytes,
+ out_buf, out_size);
+ if (ret != 0) {
+ return -1;
+ }
+
+ return MODE_MESSAGE;
+ }
+
 #ifdef FLB_HAVE_RECORD_ACCESSOR
  /*
  * Based in the configuration, decide the preferred protocol mode