out_datadog: custom added ability ot set custom HTTP headers

Author: AndrewChubatiuk

plugins/out_datadog/datadog.c

@@ -368,6 +368,10 @@ static void cb_datadog_flush(struct flb_event_chunk *event_chunk,
     size_t b_sent;
     int ret = FLB_ERROR;
     int compressed = FLB_FALSE;
+    struct mk_list *head;
+    struct flb_config_map_val *mv;
+    struct flb_slist_entry *key = NULL;
+    struct flb_slist_entry *val = NULL;
 
     /* Get upstream connection */
     upstream_conn = flb_upstream_conn_get(ctx->upstream);
@@ -427,7 +431,15 @@ static void cb_datadog_flush(struct flb_event_chunk *event_chunk,
     if (compressed == FLB_TRUE) {
         flb_http_set_content_encoding_gzip(client);
     }
-    /* TODO: Append other headers if needed*/
+
+    flb_config_map_foreach(head, mv, ctx->headers) {
+        key = mk_list_entry_first(mv->val.list, struct flb_slist_entry, _head);
+        val = mk_list_entry_last(mv->val.list, struct flb_slist_entry, _head);
+
+        flb_http_add_header(client,
+                            key->str, flb_sds_len(key->str),
+                            val->str, flb_sds_len(val->str));
+    }
 
     /* finaly send the query */
     ret = flb_http_do(client, &b_sent);
@@ -493,6 +505,11 @@ static struct flb_config_map config_map[] = {
      "compresses the payload in GZIP format, "
      "Datadog supports and recommends setting this to 'gzip'."
     },
+    {
+     FLB_CONFIG_MAP_SLIST_1, "header", NULL,
+     FLB_CONFIG_MAP_MULT, FLB_TRUE, offsetof(struct flb_out_datadog, headers),
+     "Add a HTTP header key/value pair. Multiple headers can be set"
+    },
     {
      FLB_CONFIG_MAP_STR, "apikey", NULL,
      0, FLB_TRUE, offsetof(struct flb_out_datadog, api_key),

plugins/out_datadog/datadog.h

@@ -59,6 +59,7 @@ struct flb_out_datadog {
     flb_sds_t api_key;
     int include_tag_key;
     flb_sds_t tag_key;
+    struct mk_list *headers;
     bool remap;
 
     /* final result */