enh(tmq): add demo for tmq_get_raw_meta

examples/c/tmq.c

@@ -27,7 +27,11 @@ static void msg_process(TAOS_RES* msg) {
   printf("db: %s\n", tmq_get_db_name(msg));
   printf("vg: %d\n", tmq_get_vgroup_id(msg));
   if (tmq_get_res_type(msg) == TMQ_RES_TABLE_META) {
-    printf("meta, skip\n");
+    void*   meta;
+    int32_t metaLen;
+    tmq_get_raw_meta(msg, &meta, &metaLen);
+
+    printf("meta, len is %d\n", metaLen);
     return;
   }
   while (1) {

include/client/taos.h

@@ -261,7 +261,7 @@ enum tmq_res_t {
 typedef enum tmq_res_t tmq_res_t;
 
 DLL_EXPORT tmq_res_t   tmq_get_res_type(TAOS_RES *res);
-DLL_EXPORT int32_t     tmq_get_raw_meta(TAOS_RES *res, const void **raw_meta, int32_t *raw_meta_len);
+DLL_EXPORT int32_t     tmq_get_raw_meta(TAOS_RES *res, void **raw_meta, int32_t *raw_meta_len);
 DLL_EXPORT const char *tmq_get_topic_name(TAOS_RES *res);
 DLL_EXPORT const char *tmq_get_db_name(TAOS_RES *res);
 DLL_EXPORT int32_t     tmq_get_vgroup_id(TAOS_RES *res);

source/client/src/tmq.c

@@ -1871,7 +1871,7 @@ const char* tmq_get_table_name(TAOS_RES* res) {
   return NULL;
 }
 
-int32_t tmq_get_raw_meta(TAOS_RES* res, const void** raw_meta, int32_t* raw_meta_len) {
+int32_t tmq_get_raw_meta(TAOS_RES* res, void** raw_meta, int32_t* raw_meta_len) {
   if (TD_RES_TMQ_META(res)) {
     SMqMetaRspObj* pMetaRspObj = (SMqMetaRspObj*)res;
     *raw_meta = pMetaRspObj->metaRsp.metaRsp;

source/dnode/vnode/src/tq/tq.c

@@ -306,7 +306,7 @@ int32_t tqProcessPollReq(STQ* pTq, SRpcMsg* pMsg, int32_t workerId) {
              pHead->msgType == TDMT_VND_DROP_STB || pHead->msgType == TDMT_VND_CREATE_TABLE ||
              pHead->msgType == TDMT_VND_ALTER_TABLE || pHead->msgType == TDMT_VND_DROP_TABLE ||
              pHead->msgType == TDMT_VND_DROP_TTL_TABLE);
-      // return
+      tqInfo("fetch meta msg, ver: %ld, type: %d", pHead->version, pHead->msgType);
       SMqMetaRsp metaRsp = {0};
       metaRsp.reqOffset = pReq->currentOffset;
       metaRsp.rspOffset = fetchOffset;