in_kafka: add async commit mode

Signed-off-by: HaChanHo <[email protected]>

plugins/in_kafka/in_kafka.c

@@ -181,7 +181,9 @@ static int in_kafka_collect(struct flb_input_instance *ins,
         rd_kafka_message_destroy(rkm);
 
         /* TO-DO: commit the record based on `ret` */
-        rd_kafka_commit(ctx->kafka.rk, NULL, 0);
+        rd_kafka_commit(ctx->kafka.rk, NULL, ctx->async_commit);
+
+        flb_plg_debug(ins, "offset committed(%s)", ctx->async_commit ? "async" : "sync");
 
         /* Break from the loop when reaching the limit of polling if available */
         if (ctx->polling_threshold != FLB_IN_KAFKA_UNLIMITED &&
@@ -428,6 +430,11 @@ static struct flb_config_map config_map[] = {
     0, FLB_TRUE, offsetof(struct flb_in_kafka_config, buffer_max_size),
     "Set the maximum size of chunk"
    },
+   {
+    FLB_CONFIG_MAP_BOOL, "async_commit", "false",
+    0, FLB_TRUE, offsetof(struct flb_in_kafka_config, async_commit),
+    "When enabled the offset commit operation is asynchronous"
+   },
    /* EOF */
    {0}
 };

plugins/in_kafka/in_kafka.h

@@ -48,6 +48,7 @@ struct flb_in_kafka_config {
     int coll_fd;
     size_t buffer_max_size;          /* Maximum size of chunk allocation */
     size_t polling_threshold;
+    int async_commit;
 };
 
 #endif