return last key of each meter to client

src/client/src/tscServer.c

@@ -1531,7 +1531,7 @@ static char* doSerializeTableInfo(SSqlObj* pSql, int32_t numOfMeters, int32_t vn
     SMeterSidExtInfo *pMeterInfo = (SMeterSidExtInfo *)pMsg;
     pMeterInfo->sid = htonl(pMeterMeta->sid);
     pMeterInfo->uid = htobe64(pMeterMeta->uid);
-    pMeterInfo->skey = tscGetSubscriptionProgress(pSql, pMeterMeta->uid);
+    pMeterInfo->key = htobe64(tscGetSubscriptionProgress(pSql, pMeterMeta->uid));
     pMsg += sizeof(SMeterSidExtInfo);
   } else {
     SVnodeSidList *pVnodeSidList = tscGetVnodeSidList(pMetricMeta, pMeterMetaInfo->vnodeIndex);
@@ -1542,7 +1542,7 @@ static char* doSerializeTableInfo(SSqlObj* pSql, int32_t numOfMeters, int32_t vn
       
       pMeterInfo->sid = htonl(pQueryMeterInfo->sid);
       pMeterInfo->uid = htobe64(pQueryMeterInfo->uid);
-      pMeterInfo->skey = tscGetSubscriptionProgress(pSql, pMeterMeta->uid);
+      pMeterInfo->key = htobe64(tscGetSubscriptionProgress(pSql, pQueryMeterInfo->uid));
       
       pMsg += sizeof(SMeterSidExtInfo);
       
@@ -3526,6 +3526,7 @@ int tscProcessQueryRsp(SSqlObj *pSql) {
   return 0;
 }
 
+void tscUpdateSubscriptionProgress(SSqlObj* pSql, int64_t uid, TSKEY ts);
 int tscProcessRetrieveRspFromVnode(SSqlObj *pSql) {
   SSqlRes *pRes = &pSql->res;
   SSqlCmd *pCmd = &pSql->cmd;
@@ -3536,11 +3537,25 @@ int tscProcessRetrieveRspFromVnode(SSqlObj *pSql) {
   pRes->numOfRows = htonl(pRetrieve->numOfRows);
   pRes->precision = htons(pRetrieve->precision);
   pRes->offset = htobe64(pRetrieve->offset);
-  pRes->uid = pRetrieve->uid;
   pRes->useconds = htobe64(pRetrieve->useconds);
   pRes->data = pRetrieve->data;
 
   tscSetResultPointer(pCmd, pRes);
+
+  TAOS_FIELD *pField = tscFieldInfoGetField(pCmd, pCmd->fieldsInfo.numOfOutputCols - 1);
+  int16_t     offset = tscFieldInfoGetOffset(pCmd, pCmd->fieldsInfo.numOfOutputCols - 1);
+  char* p = pRes->data + (pField->bytes + offset) * pRes->numOfRows;
+
+  int32_t numOfMeters = htonl(*(int32_t*)p);
+  p += sizeof(int32_t);
+  for (int i = 0; i < numOfMeters; i++) {
+    int64_t uid = htobe64(*(int64_t*)p);
+    p += sizeof(int64_t);
+    TSKEY key = htobe64(*(TSKEY*)p);
+    p += sizeof(TSKEY);
+    tscUpdateSubscriptionProgress(pSql, uid, key);
+  }
+
   pRes->row = 0;
 
   /**

src/client/src/tscSql.c

@@ -627,11 +627,6 @@ TAOS_ROW taos_fetch_row(TAOS_RES *res) {
       rows = taos_fetch_row_impl(res);
     }
 
-    if (rows != NULL && pSql->pSubscription != NULL) {
-      TSKEY ts = *(TSKEY*)rows[pCmd->fieldsInfo.numOfOutputCols - 1];
-      tscUpdateSubscriptionProgress(pMeterMetaInfo->pMeterMeta->uid, ts);
-    }
-
     // check!!!
     if (rows != NULL || pMeterMetaInfo->vnodeIndex >= pMeterMetaInfo->pMetricMeta->numOfVnodes) {
       break;
@@ -866,61 +861,63 @@ void taos_stop_query(TAOS_RES *res) {
 int taos_print_row(char *str, TAOS_ROW row, TAOS_FIELD *fields, int num_fields) {
   int len = 0;
   for (int i = 0; i < num_fields; ++i) {
+    if (i > 0) {
+      str[len++] = ' ';
+    }
+
     if (row[i] == NULL) {
-      len += sprintf(str + len, "%s ", TSDB_DATA_NULL_STR);
+      len += sprintf(str + len, "%s", TSDB_DATA_NULL_STR);
       continue;
     }
 
     switch (fields[i].type) {
       case TSDB_DATA_TYPE_TINYINT:
-        len += sprintf(str + len, "%d ", *((char *)row[i]));
+        len += sprintf(str + len, "%d", *((char *)row[i]));
         break;
 
       case TSDB_DATA_TYPE_SMALLINT:
-        len += sprintf(str + len, "%d ", *((short *)row[i]));
+        len += sprintf(str + len, "%d", *((short *)row[i]));
         break;
 
       case TSDB_DATA_TYPE_INT:
-        len += sprintf(str + len, "%d ", *((int *)row[i]));
+        len += sprintf(str + len, "%d", *((int *)row[i]));
         break;
 
       case TSDB_DATA_TYPE_BIGINT:
-        len += sprintf(str + len, "%" PRId64 " ", *((int64_t *)row[i]));
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
         break;
 
       case TSDB_DATA_TYPE_FLOAT: {
         float fv = 0;
         fv = GET_FLOAT_VAL(row[i]);
-        len += sprintf(str + len, "%f ", fv);
+        len += sprintf(str + len, "%f", fv);
       }
         break;
 
       case TSDB_DATA_TYPE_DOUBLE:{
         double dv = 0;
         dv = GET_DOUBLE_VAL(row[i]);
-        len += sprintf(str + len, "%lf ", dv);
+        len += sprintf(str + len, "%lf", dv);
       }
-        break;
 
       case TSDB_DATA_TYPE_BINARY:
       case TSDB_DATA_TYPE_NCHAR: {
-        /* limit the max length of string to no greater than the maximum length,
-         * in case of not null-terminated string */
-        size_t xlen = strlen(row[i]);
-        size_t trueLen = MIN(xlen, fields[i].bytes);
-
-        memcpy(str + len, (char *)row[i], trueLen);
-
-        str[len + trueLen] = ' ';
-        len += (trueLen + 1);
-      } break;
+          size_t xlen = 0;
+          for (xlen = 0; xlen <= fields[i].bytes; xlen++) {
+            char c = ((char*)row[i])[xlen];
+            if (c == 0) break;
+            str[len++] = c;
+          }
+          str[len] = 0;
+        }
+        break;
 
       case TSDB_DATA_TYPE_TIMESTAMP:
-        len += sprintf(str + len, "%" PRId64 " ", *((int64_t *)row[i]));
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
         break;
 
       case TSDB_DATA_TYPE_BOOL:
-        len += sprintf(str + len, "%d ", *((int8_t *)row[i]));
+        len += sprintf(str + len, "%d", *((int8_t *)row[i]));
       default:
         break;
     }

src/client/src/tscSub.c

@@ -80,7 +80,7 @@ void tscUpdateSubscriptionProgress(SSqlObj* pSql, int64_t uid, TSKEY ts) {
     else if (p->uid < uid)
       s = m + 1;
     else {
-      p->key = ts + 1;
+      if (ts >= p->key) p->key = ts + 1;
       break;
     }
   }
@@ -219,6 +219,7 @@ TAOS_RES *taos_consume(TAOS_SUB *tsub) {
   pRes->numOfTotal = 0;
   pRes->qhandle = 0;
   pSql->thandle = NULL;
+  pSql->cmd.command = TSDB_SQL_SELECT;
 
   tscDoQuery(pSql);
   if (pRes->code != TSDB_CODE_SUCCESS) {

src/inc/taosmsg.h

@@ -490,7 +490,7 @@ typedef struct SColumnInfo {
 typedef struct SMeterSidExtInfo {
   int32_t sid;
   int64_t uid;
-  TSKEY   skey;   // start key for subscription
+  TSKEY   key;   // key for subscription
   char    tags[];
 } SMeterSidExtInfo;
 
@@ -573,7 +573,6 @@ typedef struct {
   int16_t precision;
   int64_t offset;  // updated offset value for multi-vnode projection query
   int64_t useconds;
-  int64_t uid;
   char    data[];
 } SRetrieveMeterRsp;
 

src/system/detail/src/vnodeQueryProcess.c

@@ -750,6 +750,8 @@ static void vnodeMultiMeterMultiOutputProcessor(SQInfo *pQInfo) {
         pQuery->ekey = pSupporter->rawEKey;
         pSupporter->meterIdx++;
 
+        pQInfo->pMeterQuerySupporter->pMeterSidExtInfo[k]->key = pQuery->lastKey;
+
         // if the buffer is full or group by each table, we need to jump out of the loop
         if (Q_STATUS_EQUAL(pQuery->over, QUERY_RESBUF_FULL) ||
             isGroupbyEachTable(pQuery->pGroupbyExpr, pSupporter->pSidSet)) {
@@ -765,6 +767,7 @@ static void vnodeMultiMeterMultiOutputProcessor(SQInfo *pQInfo) {
           assert(!Q_STATUS_EQUAL(pQuery->over, QUERY_RESBUF_FULL));
           continue;
         } else {
+          pQInfo->pMeterQuerySupporter->pMeterSidExtInfo[k]->key = pQuery->lastKey;
           // buffer is full, wait for the next round to retrieve data from current meter
           assert(Q_STATUS_EQUAL(pQuery->over, QUERY_RESBUF_FULL));
           break;

src/system/detail/src/vnodeRead.c

@@ -753,7 +753,6 @@ void *vnodeQueryOnMultiMeters(SMeterObj **pMetersObj, SSqlGroupbyExpr *pGroupbyE
     taosAddIntHash(pSupporter->pMeterObj, pMetersObj[i]->sid, (char *)&pMetersObj[i]);
   }
 
-  pSupporter->pMeterSidExtInfo = (SMeterSidExtInfo **)pQueryMsg->pSidExtInfo;
   int32_t sidElemLen = pQueryMsg->tagLength + sizeof(SMeterSidExtInfo);
 
   int32_t size = POINTER_BYTES * pQueryMsg->numOfSids + sidElemLen * pQueryMsg->numOfSids;
@@ -767,12 +766,16 @@ void *vnodeQueryOnMultiMeters(SMeterObj **pMetersObj, SSqlGroupbyExpr *pGroupbyE
   char *px = ((char *)pSupporter->pMeterSidExtInfo) + POINTER_BYTES * pQueryMsg->numOfSids;
 
   for (int32_t i = 0; i < pQueryMsg->numOfSids; ++i) {
-    pSupporter->pMeterSidExtInfo[i] = (SMeterSidExtInfo *)px;
-    pSupporter->pMeterSidExtInfo[i]->sid = ((SMeterSidExtInfo **)pQueryMsg->pSidExtInfo)[i]->sid;
+    SMeterSidExtInfo* pSrc = ((SMeterSidExtInfo **)pQueryMsg->pSidExtInfo)[i];
+    SMeterSidExtInfo* pDst = (SMeterSidExtInfo *)px;
+
+    pSupporter->pMeterSidExtInfo[i] = pDst;
+    pDst->sid = pSrc->sid;
+    pDst->uid = pSrc->uid;
+    pDst->key = pSrc->key;
 
     if (pQueryMsg->tagLength > 0) {
-      memcpy(pSupporter->pMeterSidExtInfo[i]->tags, ((SMeterSidExtInfo **)pQueryMsg->pSidExtInfo)[i]->tags,
-             pQueryMsg->tagLength);
+      memcpy(pDst->tags, pSrc->tags, pQueryMsg->tagLength);
     }
     px += sidElemLen;
   }
@@ -1107,6 +1110,7 @@ int32_t vnodeConvertQueryMeterMsg(SQueryMeterMsg *pQueryMsg) {
     pSids[j] = (SMeterSidExtInfo *)((char *)pSids[j - 1] + sizeof(SMeterSidExtInfo) + pQueryMsg->tagLength);
     pSids[j]->sid = htonl(pSids[j]->sid);
     pSids[j]->uid = htobe64(pSids[j]->uid);
+    pSids[j]->key = htobe64(pSids[j]->key);
   }
 
   pMsg = (char *)pSids[pQueryMsg->numOfSids - 1];

src/system/detail/src/vnodeShell.c

@@ -412,6 +412,7 @@ void vnodeExecuteRetrieveReq(SSchedMsg *pSched) {
 
   int code = 0;
   pRetrieve = (SRetrieveMeterMsg *)pMsg;
+  SQInfo* pQInfo = (SQInfo*)pRetrieve->qhandle;
   pRetrieve->free = htons(pRetrieve->free);
 
   if ((pRetrieve->free & TSDB_QUERY_TYPE_FREE_RESOURCE) != TSDB_QUERY_TYPE_FREE_RESOURCE) {
@@ -438,7 +439,11 @@ void vnodeExecuteRetrieveReq(SSchedMsg *pSched) {
     size = vnodeGetResultSize((void *)(pRetrieve->qhandle), &numOfRows);
   }
 
-  pStart = taosBuildRspMsgWithSize(pObj->thandle, TSDB_MSG_TYPE_RETRIEVE_RSP, size + 100);
+  // buffer size for progress information, including meter count,
+  // and for each meter, including 'uid' and 'TSKEY'.
+  int progressSize = pQInfo->pMeterQuerySupporter->numOfMeters * (sizeof(int64_t) + sizeof(TSKEY)) + sizeof(int32_t);
+
+  pStart = taosBuildRspMsgWithSize(pObj->thandle, TSDB_MSG_TYPE_RETRIEVE_RSP, progressSize + size + 100);
   if (pStart == NULL) {
     taosSendSimpleRsp(pObj->thandle, TSDB_MSG_TYPE_RETRIEVE_RSP, TSDB_CODE_SERV_OUT_OF_MEMORY);
     goto _exit;
@@ -456,7 +461,6 @@ void vnodeExecuteRetrieveReq(SSchedMsg *pSched) {
   if (code == TSDB_CODE_SUCCESS) {
     pRsp->offset = htobe64(vnodeGetOffsetVal((void*)pRetrieve->qhandle));
     pRsp->useconds = htobe64(((SQInfo *)(pRetrieve->qhandle))->useconds);
-    pRsp->uid = ((SQInfo *)(pRetrieve->qhandle))->pObj->uid;
   } else {
     pRsp->offset = 0;
     pRsp->useconds = 0;
@@ -469,11 +473,23 @@ void vnodeExecuteRetrieveReq(SSchedMsg *pSched) {
   }
 
   pMsg += size;
+
+  // write the progress information of each meter to response
+  // this is required by subscriptions
+  *((int32_t*)pMsg) = htonl(pQInfo->pMeterQuerySupporter->numOfMeters);
+  pMsg += sizeof(int32_t);
+  for (int32_t i = 0; i < pQInfo->pMeterQuerySupporter->numOfMeters; i++) {
+    *((int64_t*)pMsg) = htobe64(pQInfo->pMeterQuerySupporter->pMeterSidExtInfo[i]->uid);
+    pMsg += sizeof(int64_t);
+    *((TSKEY*)pMsg) = htobe64(pQInfo->pMeterQuerySupporter->pMeterSidExtInfo[i]->key);
+    pMsg += sizeof(TSKEY);
+  }
+
   msgLen = pMsg - pStart;
 
   assert(code != TSDB_CODE_ACTION_IN_PROGRESS);
   
-  if (numOfRows == 0 && (pRetrieve->qhandle == (uint64_t)pObj->qhandle) && (code != TSDB_CODE_ACTION_IN_PROGRESS)) {
+  if (numOfRows == 0 && (pRetrieve->qhandle == (uint64_t)pObj->qhandle) && (code != TSDB_CODE_ACTION_IN_PROGRESS) && pRetrieve->qhandle != NULL) {
     dTrace("QInfo:%p %s free qhandle code:%d", pObj->qhandle, __FUNCTION__, code);
     vnodeDecRefCount(pObj->qhandle);
     pObj->qhandle = NULL;