[td-13039] add system table scanner.

include/common/tmsg.h

@@ -836,6 +836,8 @@ int32_t tDeserializeSShowRsp(void* buf, int32_t bufLen, SShowRsp* pRsp);
 void    tFreeSShowRsp(SShowRsp* pRsp);
 
 typedef struct {
+  int32_t type;
+  char    db[TSDB_DB_FNAME_LEN];
   int64_t showId;
   int8_t  free;
 } SRetrieveTableReq;

include/common/tmsgdef.h

@@ -134,6 +134,7 @@ enum {
   TD_DEF_MSG_TYPE(TDMT_MND_HEARTBEAT, "mnode-heartbeat", SClientHbBatchReq, SClientHbBatchRsp)
   TD_DEF_MSG_TYPE(TDMT_MND_SHOW, "mnode-show", NULL, NULL)
   TD_DEF_MSG_TYPE(TDMT_MND_SHOW_RETRIEVE, "mnode-retrieve", NULL, NULL)
+  TD_DEF_MSG_TYPE(TDMT_MND_SYSTABLE_RETRIEVE, "mnode-systable-retrieve", NULL, NULL)
   TD_DEF_MSG_TYPE(TDMT_MND_STATUS, "mnode-status", NULL, NULL)
   TD_DEF_MSG_TYPE(TDMT_MND_TRANS_TIMER, "mnode-trans-tmr", NULL, NULL)
   TD_DEF_MSG_TYPE(TDMT_MND_KILL_TRANS, "mnode-kill-trans", NULL, NULL)

include/libs/nodes/nodes.h

@@ -106,6 +106,7 @@ typedef enum ENodeType {
   QUERY_NODE_PHYSICAL_PLAN_TABLE_SCAN,
   QUERY_NODE_PHYSICAL_PLAN_TABLE_SEQ_SCAN,
   QUERY_NODE_PHYSICAL_PLAN_STREAM_SCAN,
+  QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN,
   QUERY_NODE_PHYSICAL_PLAN_PROJECT,
   QUERY_NODE_PHYSICAL_PLAN_JOIN,
   QUERY_NODE_PHYSICAL_PLAN_AGG,

source/dnode/mnode/impl/inc/mndDef.h

@@ -353,6 +353,23 @@ typedef struct {
   char    payload[];
 } SShowObj;
 
+typedef struct {
+  int64_t id;
+  int8_t  type;
+  int8_t  replica;
+  int16_t numOfColumns;
+  int32_t rowSize;
+  int32_t numOfRows;
+  int32_t numOfReads;
+  int32_t payloadLen;
+  void*   pIter;
+  SMnode* pMnode;
+  char    db[TSDB_DB_FNAME_LEN];
+  int16_t offset[TSDB_MAX_COLUMNS];
+  int32_t bytes[TSDB_MAX_COLUMNS];
+  char    payload[];
+} SSysTableRetrieveObj;
+
 typedef struct {
   int32_t vgId;  // -1 for unassigned
   int32_t status;

source/dnode/mnode/impl/src/mndShow.c

@@ -25,6 +25,7 @@ static void      mndReleaseShowObj(SShowObj *pShow, bool forceRemove);
 static int32_t   mndProcessShowReq(SMnodeMsg *pReq);
 static int32_t   mndProcessRetrieveReq(SMnodeMsg *pReq);
 static bool      mndCheckRetrieveFinished(SShowObj *pShow);
+static int32_t   mndProcessRetrieveSysTableReq(SMnodeMsg *pReq);
 
 int32_t mndInitShow(SMnode *pMnode) {
   SShowMgmt *pMgmt = &pMnode->showMgmt;
@@ -38,6 +39,7 @@ int32_t mndInitShow(SMnode *pMnode) {
 
   mndSetMsgHandle(pMnode, TDMT_MND_SHOW, mndProcessShowReq);
   mndSetMsgHandle(pMnode, TDMT_MND_SHOW_RETRIEVE, mndProcessRetrieveReq);
+  mndSetMsgHandle(pMnode, TDMT_MND_SYSTABLE_RETRIEVE, mndProcessRetrieveSysTableReq);
   return 0;
 }
 
@@ -261,6 +263,106 @@ static int32_t mndProcessRetrieveReq(SMnodeMsg *pReq) {
   return TSDB_CODE_SUCCESS;
 }
 
+static int32_t mndProcessRetrieveSysTableReq(SMnodeMsg *pReq) {
+  SMnode    *pMnode = pReq->pMnode;
+  SShowMgmt *pMgmt = &pMnode->showMgmt;
+  int32_t    rowsToRead = 0;
+  int32_t    size = 0;
+  int32_t    rowsRead = 0;
+
+  SRetrieveTableReq retrieveReq = {0};
+  if (tDeserializeSRetrieveTableReq(pReq->rpcMsg.pCont, pReq->rpcMsg.contLen, &retrieveReq) != 0) {
+    terrno = TSDB_CODE_INVALID_MSG;
+    return -1;
+  }
+
+  SShowObj* pShow = NULL;
+
+  if (retrieveReq.showId == 0) {
+    SShowReq req = {0};
+    req.type = retrieveReq.type;
+    strncpy(req.db, retrieveReq.db, tListLen(req.db));
+
+    pShow = mndCreateShowObj(pMnode, &req);
+    if (pShow == NULL) {
+      terrno = TSDB_CODE_OUT_OF_MEMORY;
+      mError("failed to process show-meta req since %s", terrstr());
+      return -1;
+    }
+  } else {
+    pShow = mndAcquireShowObj(pMnode, retrieveReq.showId);
+    if (pShow == NULL) {
+      terrno = TSDB_CODE_MND_INVALID_SHOWOBJ;
+      mError("failed to process show-retrieve req:%p since %s", pShow, terrstr());
+      return -1;
+    }
+  }
+
+  ShowRetrieveFp retrieveFp = pMgmt->retrieveFps[pShow->type];
+  if (retrieveFp == NULL) {
+    mndReleaseShowObj((SShowObj*) pShow, false);
+    terrno = TSDB_CODE_MSG_NOT_PROCESSED;
+    mError("show:0x%" PRIx64 ", failed to retrieve data since %s", pShow->id, terrstr());
+    return -1;
+  }
+
+  mDebug("show:0x%" PRIx64 ", start retrieve data, numOfReads:%d numOfRows:%d type:%s", pShow->id, pShow->numOfReads,
+         pShow->numOfRows, mndShowStr(pShow->type));
+
+  if (mndCheckRetrieveFinished((SShowObj*) pShow)) {
+    mDebug("show:0x%" PRIx64 ", read finished, numOfReads:%d numOfRows:%d", pShow->id, pShow->numOfReads,
+           pShow->numOfRows);
+    pShow->numOfReads = pShow->numOfRows;
+  }
+
+  if ((retrieveReq.free & TSDB_QUERY_TYPE_FREE_RESOURCE) != TSDB_QUERY_TYPE_FREE_RESOURCE) {
+    rowsToRead = pShow->numOfRows - pShow->numOfReads;
+  }
+
+  /* return no more than 100 tables in one round trip */
+  if (rowsToRead > SHOW_STEP_SIZE) rowsToRead = SHOW_STEP_SIZE;
+
+  /*
+   * the actual number of table may be larger than the value of pShow->numOfRows, if a query is
+   * issued during a continuous create table operation. Therefore, rowToRead may be less than 0.
+   */
+  if (rowsToRead < 0) rowsToRead = 0;
+  size = pShow->rowSize * rowsToRead;
+
+  size += SHOW_STEP_SIZE;
+  SRetrieveTableRsp *pRsp = rpcMallocCont(size);
+  if (pRsp == NULL) {
+    mndReleaseShowObj((SShowObj*) pShow, false);
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    mError("show:0x%" PRIx64 ", failed to retrieve data since %s", pShow->id, terrstr());
+    return -1;
+  }
+
+  // if free flag is set, client wants to clean the resources
+  if ((retrieveReq.free & TSDB_QUERY_TYPE_FREE_RESOURCE) != TSDB_QUERY_TYPE_FREE_RESOURCE) {
+    rowsRead = (*retrieveFp)(pReq, (SShowObj*) pShow, pRsp->data, rowsToRead);
+  }
+
+  mDebug("show:0x%" PRIx64 ", stop retrieve data, rowsRead:%d rowsToRead:%d", pShow->id, rowsRead, rowsToRead);
+
+  pRsp->numOfRows = htonl(rowsRead);
+  pRsp->precision = TSDB_TIME_PRECISION_MILLI;  // millisecond time precision
+
+  pReq->pCont = pRsp;
+  pReq->contLen = size;
+
+  if (rowsRead == 0 || rowsToRead == 0 || (rowsRead == rowsToRead && pShow->numOfRows == pShow->numOfReads)) {
+    pRsp->completed = 1;
+    mDebug("show:0x%" PRIx64 ", retrieve completed", pShow->id);
+    mndReleaseShowObj((SShowObj*) pShow, true);
+  } else {
+    mDebug("show:0x%" PRIx64 ", retrieve not completed yet", pShow->id);
+    mndReleaseShowObj((SShowObj*) pShow, false);
+  }
+
+  return TSDB_CODE_SUCCESS;
+}
+
 char *mndShowStr(int32_t showType) {
   switch (showType) {
     case TSDB_MGMT_TABLE_ACCT:

source/libs/executor/inc/executorimpl.h

@@ -410,12 +410,10 @@ typedef struct STableScanInfo {
   int32_t         numOfSkipped;
   int32_t         numOfBlockStatis;
   int64_t         numOfRows;
-
   int32_t         order;  // scan order
   int32_t         times;  // repeat counts
   int32_t         current;
   int32_t         reverseTimes;  // 0 by default
-
   SqlFunctionCtx* pCtx;  // next operator query context
   SResultRowInfo* pResultRowInfo;
   int32_t*        rowCellInfoOffset;
@@ -424,7 +422,6 @@ typedef struct STableScanInfo {
   int32_t         numOfOutput;
   int64_t         elapsedTime;
   int32_t         prevGroupId;  // previous table group id
-
   int32_t         scanFlag;  // table scan flag to denote if it is a repeat/reverse/main scan
 } STableScanInfo;
 
@@ -443,6 +440,20 @@ typedef struct SStreamBlockScanInfo {
   void*        readerHandle;  // stream block reader handle
 } SStreamBlockScanInfo;
 
+typedef struct SSysTableScanInfo {
+  void        *pTransporter;
+  SEpSet       epSet;
+  int32_t      type;   // show type
+  tsem_t       ready;
+  void        *readHandle;
+  SSchema     *pSchema;
+  SSDataBlock *pRes;
+  int64_t      numOfBlocks;  // extract basic running information.
+  int64_t      totalRows;
+  int64_t      elapsedTime;
+  int64_t      totalBytes;
+} SSysTableScanInfo;
+
 typedef struct SOptrBasicInfo {
   SResultRowInfo  resultRowInfo;
   int32_t*        rowCellInfoOffset;  // offset value for each row result cell info
@@ -612,13 +623,14 @@ typedef struct SOrderOperatorInfo {
   uint64_t                totalElapsed;  // total elapsed time
 } SOrderOperatorInfo;
 
-SOperatorInfo* createExchangeOperatorInfo(const SArray* pSources, const SArray* pSchema, SExecTaskInfo* pTaskInfo);
+SOperatorInfo* createExchangeOperatorInfo(const SArray* pSources, const SArray* pExprInfo, SExecTaskInfo* pTaskInfo);
 SOperatorInfo* createTableScanOperatorInfo(void* pTsdbReadHandle, int32_t order, int32_t numOfOutput,
                                            int32_t repeatTime, int32_t reverseTime, SExecTaskInfo* pTaskInfo);
 SOperatorInfo* createTableSeqScanOperatorInfo(void* pTsdbReadHandle, STaskRuntimeEnv* pRuntimeEnv);
 SOperatorInfo* createAggregateOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SSDataBlock* pResultBlock, SExecTaskInfo* pTaskInfo, const STableGroupInfo* pTableGroupInfo);
 SOperatorInfo* createMultiTableAggOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SSDataBlock* pResultBlock, SExecTaskInfo* pTaskInfo, const STableGroupInfo* pTableGroupInfo);
 SOperatorInfo* createProjectOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SExecTaskInfo* pTaskInfo);
+SOperatorInfo* createSystemScanOperatorInfo(void* pSystemTableReadHandle, const SArray* pExprInfo, const SSchema* pSchema, SExecTaskInfo* pTaskInfo);
 
 SOperatorInfo* createLimitOperatorInfo(STaskRuntimeEnv* pRuntimeEnv, SOperatorInfo* downstream);
 SOperatorInfo* createIntervalOperatorInfo(SOperatorInfo* downstream, SArray* pExprInfo, SInterval* pInterval, SExecTaskInfo* pTaskInfo);

source/libs/executor/src/executorimpl.c

@@ -5353,7 +5353,6 @@ SOperatorInfo* createTableScanOperatorInfo(void* pTsdbReadHandle, int32_t order,
   pInfo->order             = order;
   pInfo->current           = 0;
   pInfo->scanFlag          = MAIN_SCAN;
-
   pOperator->name          = "TableScanOperator";
   pOperator->operatorType  = QUERY_NODE_PHYSICAL_PLAN_TABLE_SCAN;
   pOperator->blockingOptr  = false;
@@ -5456,6 +5455,80 @@ SOperatorInfo* createStreamScanOperatorInfo(void *streamReadHandle, SArray* pExp
   return pOperator;
 }
 
+
+static int32_t loadSysTableContentCb(void* param, const SDataBuf* pMsg, int32_t code) {
+  SSourceDataInfo* pSourceDataInfo = (SSourceDataInfo*) param;
+  pSourceDataInfo->pRsp = pMsg->pData;
+
+  SRetrieveTableRsp* pRsp = pSourceDataInfo->pRsp;
+  pRsp->numOfRows = htonl(pRsp->numOfRows);
+  pRsp->useconds  = htobe64(pRsp->useconds);
+  pRsp->compLen   = htonl(pRsp->compLen);
+
+  pSourceDataInfo->status = DATA_READY;
+  tsem_post(&pSourceDataInfo->pEx->ready);
+}
+
+static SSDataBlock* doSysTableScan(void* param, bool* newgroup) {
+// build message and send to mnode to fetch the content of system tables.
+  SOperatorInfo* pOperator = (SOperatorInfo*) param;
+  SExecTaskInfo* pTaskInfo = pOperator->pTaskInfo;
+  SSysTableScanInfo* pInfo = pOperator->info;
+
+  SRetrieveTableReq* req = calloc(1, sizeof(SRetrieveTableReq));
+  if (req == NULL) {
+    pTaskInfo->code = TSDB_CODE_OUT_OF_MEMORY;
+    return NULL;
+  }
+
+  req->type = pInfo->type;
+
+  // send the fetch remote task result reques
+  SMsgSendInfo* pMsgSendInfo = calloc(1, sizeof(SMsgSendInfo));
+  if (NULL == pMsgSendInfo) {
+    qError("%s prepare message %d failed", GET_TASKID(pTaskInfo), (int32_t)sizeof(SMsgSendInfo));
+    pTaskInfo->code = TSDB_CODE_QRY_OUT_OF_MEMORY;
+    return NULL;
+  }
+
+  pMsgSendInfo->param = NULL;
+  pMsgSendInfo->msgInfo.pData = req;
+  pMsgSendInfo->msgInfo.len = sizeof(SRetrieveTableReq);
+  pMsgSendInfo->msgType = TDMT_MND_SYSTABLE_RETRIEVE;
+  pMsgSendInfo->fp = loadRemoteDataCallback;
+
+  int64_t transporterId = 0;
+  int32_t code = asyncSendMsgToServer(pInfo->pTransporter, &pInfo->epSet, &transporterId, pMsgSendInfo);
+
+  tsem_wait(&pInfo->ready);
+  // handle the response and return to the caller
+
+  return NULL;
+}
+
+SOperatorInfo* createSystemScanOperatorInfo(void* pSysTableReadHandle, const SArray* pExprInfo, const SSchema* pSchema, SExecTaskInfo* pTaskInfo) {
+  SSysTableScanInfo* pInfo = calloc(1, sizeof(SSysTableScanInfo));
+  SOperatorInfo* pOperator = calloc(1, sizeof(SOperatorInfo));
+  if (pInfo == NULL || pOperator == NULL) {
+    tfree(pInfo);
+    tfree(pOperator);
+    terrno = TSDB_CODE_QRY_OUT_OF_MEMORY;
+    return NULL;
+  }
+
+  pInfo->readHandle        = pSysTableReadHandle;
+  pOperator->name          = "SysTableScanOperator";
+  pOperator->operatorType  = QUERY_NODE_PHYSICAL_PLAN_SYSTABLE_SCAN;
+  pOperator->blockingOptr  = false;
+  pOperator->status        = OP_IN_EXECUTING;
+  pOperator->info          = pInfo;
+  pOperator->numOfOutput   = taosArrayGetSize(pExprInfo);
+  pOperator->nextDataFn    = doSysTableScan;
+  pOperator->pTaskInfo     = pTaskInfo;
+
+  return pOperator;
+}
+
 void setTableScanFilterOperatorInfo(STableScanInfo* pTableScanInfo, SOperatorInfo* pDownstream) {
   assert(pTableScanInfo != NULL && pDownstream != NULL);