filter_parser: Add parameter to nest parsed fields under

plugins/filter_parser/filter_parser.c

@@ -93,6 +93,53 @@ static int delete_parsers(struct filter_parser_ctx *ctx)
     return c;
 }
 
+static int nest_raw_map(struct filter_parser_ctx *ctx,
+                        char **buf,
+                        size_t *size,
+                        const flb_sds_t key)
+{
+    msgpack_sbuffer sbuf;
+    msgpack_packer pk;
+    msgpack_unpacked outbuf_result;
+    msgpack_object obj;
+    msgpack_object_kv *kv;
+    const size_t key_len = flb_sds_len(key);
+    int ret = 0;
+
+    msgpack_sbuffer_init(&sbuf);
+    msgpack_packer_init(&pk, &sbuf, msgpack_sbuffer_write);
+
+    msgpack_unpacked_init(&outbuf_result);
+    ret = msgpack_unpack_next(&outbuf_result, *buf, *size, NULL);
+    if (ret != MSGPACK_UNPACK_SUCCESS) {
+        flb_plg_error(ctx->ins,
+                      "Nest: failed to unpack msgpack data with error code %d",
+                      ret);
+        msgpack_unpacked_destroy(&outbuf_result);
+        return -1;
+    }
+
+    /* Create a new map, unpacking map `buf` under the new `key` root key */
+    obj = outbuf_result.data;
+    if (obj.type == MSGPACK_OBJECT_MAP) {
+        msgpack_pack_map(&pk, 1);
+        msgpack_pack_str(&pk, key_len);
+        msgpack_pack_str_body(&pk, key, key_len);
+        msgpack_pack_map(&pk, obj.via.map.size);
+        for (unsigned x = 0; x < obj.via.map.size; ++x) {
+            kv = &obj.via.map.ptr[x];
+            msgpack_pack_object(&pk, kv->key);
+            msgpack_pack_object(&pk, kv->val);
+        }
+        flb_free(*buf);
+        *buf = sbuf.data;
+        *size = sbuf.size;
+    }
+
+    msgpack_unpacked_destroy(&outbuf_result);
+    return 0;
+}
+
 static int configure(struct filter_parser_ctx *ctx,
                      struct flb_filter_instance *f_ins,
                      struct flb_config *config)
@@ -301,6 +348,9 @@ static int cb_parser_filter(const void *data, size_t bytes,
             }
 
             if (out_buf != NULL && parse_ret >= 0) {
+                if (ctx->nest_under) {
+                    nest_raw_map(ctx, &out_buf, &out_size, ctx->nest_under);
+                }
                 if (append_arr != NULL && append_arr_len > 0) {
                     char *new_buf = NULL;
                     int new_size;
@@ -440,6 +490,11 @@ static struct flb_config_map config_map[] = {
      "Keep all other original fields in the parsed result. "
      "If false, all other original fields will be removed."
     },
+    {
+     FLB_CONFIG_MAP_STR, "Nest_Under", NULL,
+     0, FLB_TRUE, offsetof(struct filter_parser_ctx, nest_under),
+     "Specify field name to nest parsed records under."
+    },
     {
      FLB_CONFIG_MAP_DEPRECATED, "Unescape_key", NULL,
      0, FLB_FALSE, 0,

plugins/filter_parser/filter_parser.h

@@ -35,6 +35,7 @@ struct filter_parser_ctx {
     int    key_name_len;
     int    reserve_data;
     int    preserve_key;
+    flb_sds_t nest_under;
     struct mk_list parsers;
     struct flb_filter_instance *ins;
 };

tests/runtime/filter_parser.c

@@ -1299,6 +1299,83 @@ void flb_test_filter_parser_reserve_on_preserve_on()
     test_ctx_destroy(ctx);
 }
 
+void flb_test_filter_parser_nest_under_on()
+{
+    int ret;
+    int bytes;
+    char *p, *output, *expected;
+    flb_ctx_t *ctx;
+    int in_ffd;
+    int out_ffd;
+    int filter_ffd;
+    struct flb_parser *parser;
+
+    struct flb_lib_out_cb cb;
+    cb.cb   = callback_test;
+    cb.data = NULL;
+
+    clear_output();
+
+    ctx = flb_create();
+
+    /* Configure service */
+    flb_service_set(ctx, "Flush", FLUSH_INTERVAL, "Grace" "1", "Log_Level", "debug", NULL);
+
+    /* Input */
+    in_ffd = flb_input(ctx, (char *) "lib", NULL);
+    TEST_CHECK(in_ffd >= 0);
+    flb_input_set(ctx, in_ffd,
+                  "Tag", "test",
+                  NULL);
+
+    /* Parser */
+    parser = flb_parser_create("json", "json", NULL,
+                               FLB_FALSE,
+                               NULL, NULL, NULL, MK_FALSE, MK_TRUE, FLB_FALSE, FLB_FALSE,
+                               NULL, 0, NULL, ctx->config);
+    TEST_CHECK(parser != NULL);
+
+    /* Filter */
+    filter_ffd = flb_filter(ctx, (char *) "parser", NULL);
+    TEST_CHECK(filter_ffd >= 0);
+    ret = flb_filter_set(ctx, filter_ffd,
+                         "Match", "test",
+                         "Key_Name", "to_parse",
+                         "Nest_Under", "nest_key",
+                         "Parser", "json",
+                         NULL);
+    TEST_CHECK(ret == 0);
+
+    /* Output */
+    out_ffd = flb_output(ctx, (char *) "lib", &cb);
+    TEST_CHECK(out_ffd >= 0);
+    flb_output_set(ctx, out_ffd,
+                   "Match", "*",
+                   "format", "json",
+                   NULL);
+
+    /* Start the engine */
+    ret = flb_start(ctx);
+    TEST_CHECK(ret == 0);
+
+    /* Ingest data */
+    p = "[1,{\"hello\":\"world\",\"some_object\":{\"foo\":\"bar\"},\"to_parse\":\"{\\\"key\\\":\\\"value\\\",\\\"object\\\":{\\\"a\\\":\\\"b\\\"}}\"}]";
+    bytes = flb_lib_push(ctx, in_ffd, p, strlen(p));
+    TEST_CHECK(bytes == strlen(p));
+
+    wait_with_timeout(1500, &output); /* waiting flush and ensuring data flush */
+    TEST_CHECK_(output != NULL, "Expected output to not be NULL");
+    if (output != NULL) {
+        /* check extra data was not preserved */
+        expected = "{\"nest_key\":{\"key\":\"value\",\"object\":{\"a\":\"b\"}}}";
+        TEST_CHECK_(strstr(output, expected) != NULL, "Expected output to contain key one , got '%s'", output);
+        free(output);
+    }
+
+    flb_stop(ctx);
+    flb_destroy(ctx);
+}
+
 TEST_LIST = {
     {"filter_parser_extract_fields", flb_test_filter_parser_extract_fields },
     {"filter_parser_reserve_data_off", flb_test_filter_parser_reserve_data_off },
@@ -1313,6 +1390,7 @@ TEST_LIST = {
     {"filter_parser_reserve_off_preserve_on", flb_test_filter_parser_reserve_off_preserve_on},
     {"filter_parser_reserve_on_preserve_off", flb_test_filter_parser_reserve_on_preserve_off},
     {"filter_parser_reserve_on_preserve_on", flb_test_filter_parser_reserve_on_preserve_on},
+    {"filter_parser_nest_under_on", flb_test_filter_parser_nest_under_on},
     {NULL, NULL}
 };