out_opensearch: fix trace_error truncating the response

Signed-off-by: Wesley Pettit <[email protected]>

Author: PettitWesley

plugins/out_opensearch/opensearch.c

@@ -902,13 +902,25 @@ static void cb_opensearch_flush(struct flb_event_chunk *event_chunk,
                 /* we got an error */
                 if (ctx->trace_error) {
                     /*
-                     * If trace_error is set, trace the actual input/output to
-                     * OpenSearch that caused the problem.
+                     * If trace_error is set, trace the actual
+                     * response from Elasticsearch explaining the problem.
+                     * Trace_Output can be used to see the request. 
                      */
-                    flb_plg_debug(ctx->ins, "error caused by: Input\n%s\n",
-                                  pack);
-                    flb_plg_error(ctx->ins, "error: Output\n%s",
-                                  c->resp.payload);
+                    if (pack_size < 4000) {
+                        flb_plg_debug(ctx->ins, "error caused by: Input\n%.*s\n",
+                                      (int) pack_size, pack);
+                    }
+                    if (c->resp.payload_size < 4000) {
+                        flb_plg_error(ctx->ins, "error: Output\n%s",
+                                      c->resp.payload);
+                    } else {
+                        /*
+                        * We must use fwrite since the flb_log functions
+                        * will truncate data at 4KB
+                        */
+                        fwrite(c->resp.payload, 1, c->resp.payload_size, stderr);
+                        fflush(stderr);
+                    }
                 }
                 goto retry;
             }