enh(stream): directly dispatch

include/libs/stream/tstream.h

@@ -479,7 +479,7 @@ int32_t streamLaunchByWrite(SStreamTask* pTask, int32_t vgId);
 int32_t streamSetupTrigger(SStreamTask* pTask);
 
 int32_t streamProcessRunReq(SStreamTask* pTask);
-int32_t streamProcessDispatchReq(SStreamTask* pTask, SStreamDispatchReq* pReq, SRpcMsg* pMsg);
+int32_t streamProcessDispatchReq(SStreamTask* pTask, SStreamDispatchReq* pReq, SRpcMsg* pMsg, bool exec);
 int32_t streamProcessDispatchRsp(SStreamTask* pTask, SStreamDispatchRsp* pRsp);
 int32_t streamProcessRecoverReq(SStreamTask* pTask, SStreamTaskRecoverReq* pReq, SRpcMsg* pMsg);
 int32_t streamProcessRecoverRsp(SStreamTask* pTask, SStreamTaskRecoverRsp* pRsp);
@@ -487,6 +487,18 @@ int32_t streamProcessRecoverRsp(SStreamTask* pTask, SStreamTaskRecoverRsp* pRsp)
 int32_t streamProcessRetrieveReq(SStreamTask* pTask, SStreamRetrieveReq* pReq, SRpcMsg* pMsg);
 int32_t streamProcessRetrieveRsp(SStreamTask* pTask, SStreamRetrieveRsp* pRsp);
 
+typedef struct SStreamMeta SStreamMeta;
+
+SStreamMeta* streamMetaOpen();
+void         streamMetaClose(SStreamMeta* streamMeta);
+
+int32_t streamMetaAddTask(SStreamMeta* pMeta, SStreamTask* pTask);
+int32_t streamMetaRemoveTask(SStreamMeta* pMeta, int32_t taskId);
+
+int32_t streamMetaBegin(SStreamMeta* pMeta);
+int32_t streamMetaCommit(SStreamMeta* pMeta);
+int32_t streamMetaRollBack(SStreamMeta* pMeta);
+
 #ifdef __cplusplus
 }
 #endif

source/dnode/mgmt/mgmt_vnode/src/vmWorker.c

@@ -165,7 +165,11 @@ static int32_t vmPutMsgToQueue(SVnodeMgmt *pMgmt, SRpcMsg *pMsg, EQueueType qtyp
       break;
     case STREAM_QUEUE:
       dGTrace("vgId:%d, msg:%p put into vnode-stream queue", pVnode->vgId, pMsg);
+      if (pMsg->msgType == TDMT_STREAM_TASK_DISPATCH) {
+        vnodeEnqueueStreamMsg(pVnode->pImpl, pMsg);
+      } else {
         taosWriteQitem(pVnode->pStreamQ, pMsg);
+      }
       break;
     case FETCH_QUEUE:
       dGTrace("vgId:%d, msg:%p put into vnode-fetch queue", pVnode->vgId, pMsg);

source/dnode/snode/inc/sndInt.h

@@ -30,6 +30,7 @@
 extern "C" {
 #endif
 
+#if 0
 typedef struct {
   SHashObj* pHash;  // taskId -> SStreamTask
 } SStreamMeta;
@@ -49,6 +50,7 @@ int32_t      sndMetaRemoveTask(SStreamMeta* pMeta, int32_t taskId);
 int32_t sndDropTaskOfStream(SStreamMeta* pMeta, int64_t streamId);
 int32_t sndStopTaskOfStream(SStreamMeta* pMeta, int64_t streamId);
 int32_t sndResumeTaskOfStream(SStreamMeta* pMeta, int64_t streamId);
+#endif
 
 #ifdef __cplusplus
 }

source/dnode/snode/src/snode.c

@@ -16,7 +16,12 @@
 #include "executor.h"
 #include "sndInt.h"
 #include "tuuid.h"
+SSnode *sndOpen(const char *path, const SSnodeOpt *pOption) { return NULL; }
+void    sndClose(SSnode *pSnode) {}
+int32_t sndProcessUMsg(SSnode *pSnode, SRpcMsg *pMsg) { return 0; }
+int32_t sndProcessSMsg(SSnode *pSnode, SRpcMsg *pMsg) { return 0; }
 
+#if 0
 SSnode *sndOpen(const char *path, const SSnodeOpt *pOption) {
   SSnode *pSnode = taosMemoryCalloc(1, sizeof(SSnode));
   if (pSnode == NULL) {
@@ -151,7 +156,7 @@ static int32_t sndProcessTaskDispatchReq(SSnode *pNode, SRpcMsg *pMsg) {
            .info = pMsg->info,
            .code = 0,
   };
-  streamProcessDispatchReq(pTask, &req, &rsp);
+  streamProcessDispatchReq(pTask, &req, &rsp, true);
   return 0;
 }
 
@@ -263,3 +268,4 @@ int32_t sndProcessSMsg(SSnode *pSnode, SRpcMsg *pMsg) {
   }
   return 0;
 }
+#endif

source/dnode/vnode/inc/vnode.h

@@ -183,6 +183,8 @@ bool    tqNextDataBlock(STqReader *pReader);
 bool    tqNextDataBlockFilterOut(STqReader *pReader, SHashObj *filterOutUids);
 int32_t tqRetrieveDataBlock(SSDataBlock *pBlock, STqReader *pReader);
 
+void vnodeEnqueueStreamMsg(SVnode *pVnode, SRpcMsg *pMsg);
+
 // sma
 int32_t smaGetTSmaDays(SVnodeCfg *pCfg, void *pCont, uint32_t contLen, int32_t *days);
 

source/dnode/vnode/src/inc/tq.h

@@ -115,15 +115,23 @@ typedef struct {
 } STqHandle;
 
 struct STQ {
+  SVnode*   pVnode;
   char*     path;
   SHashObj* pushMgr;       // consumerId -> STqHandle*
   SHashObj* handles;       // subKey -> STqHandle
   SHashObj* pStreamTasks;  // taksId -> SStreamTask
   SHashObj* pAlterInfo;    // topic -> SAlterCheckInfo
+
   STqOffsetStore* pOffsetStore;
-  SVnode*         pVnode;
+
   TDB* pMetaStore;
   TTB* pExecStore;
+
+  TTB* pAlterInfoStore;
+
+  TDB* pStreamStore;
+  TTB* pTaskDb;
+  TTB* pTaskState;
 };
 
 typedef struct {

source/dnode/vnode/src/inc/vnodeInt.h

@@ -162,7 +162,7 @@ int32_t tqProcessTaskDeployReq(STQ* pTq, char* msg, int32_t msgLen);
 int32_t tqProcessTaskDropReq(STQ* pTq, char* msg, int32_t msgLen);
 int32_t tqProcessStreamTrigger(STQ* pTq, SSubmitReq* data, int64_t ver);
 int32_t tqProcessTaskRunReq(STQ* pTq, SRpcMsg* pMsg);
-int32_t tqProcessTaskDispatchReq(STQ* pTq, SRpcMsg* pMsg);
+int32_t tqProcessTaskDispatchReq(STQ* pTq, SRpcMsg* pMsg, bool exec);
 int32_t tqProcessTaskRecoverReq(STQ* pTq, SRpcMsg* pMsg);
 int32_t tqProcessTaskDispatchRsp(STQ* pTq, SRpcMsg* pMsg);
 int32_t tqProcessTaskRecoverRsp(STQ* pTq, SRpcMsg* pMsg);

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

@@ -280,8 +280,6 @@ static int32_t tqInitDataRsp(SMqDataRsp* pRsp, const SMqPollReq* pReq, int8_t su
   return 0;
 }
 
-static int32_t tqInitMetaRsp(SMqMetaRsp* pRsp, const SMqPollReq* pReq) { return 0; }
-
 int32_t tqProcessPollReq(STQ* pTq, SRpcMsg* pMsg) {
   SMqPollReq*  pReq = pMsg->pCont;
   int64_t      consumerId = pReq->consumerId;
@@ -386,6 +384,7 @@ int32_t tqProcessPollReq(STQ* pTq, SRpcMsg* pMsg) {
   }
 
   if (pHandle->execHandle.subType != TOPIC_SUB_TYPE__COLUMN) {
+    ASSERT(fetchOffsetNew.type == TMQ_OFFSET__LOG);
     int64_t fetchVer = fetchOffsetNew.version + 1;
     pCkHead = taosMemoryMalloc(sizeof(SWalCkHead) + 2048);
     if (pCkHead == NULL) {
@@ -461,22 +460,6 @@ int32_t tqProcessPollReq(STQ* pTq, SRpcMsg* pMsg) {
         goto OVER;
       }
     }
-
-    taosMemoryFree(pCkHead);
-#if 0
-  } else if (fetchOffsetNew.type == TMQ_OFFSET__SNAPSHOT_DATA) {
-    tqInfo("retrieve using snapshot actual offset: uid %" PRId64 " ts %" PRId64, fetchOffsetNew.uid, fetchOffsetNew.ts);
-    if (tqScanSnapshot(pTq, &pHandle->execHandle, &dataRsp, fetchOffsetNew, workerId) < 0) {
-      ASSERT(0);
-    }
-
-    // 4. send rsp
-    if (tqSendDataRsp(pTq, pMsg, pReq, &dataRsp) < 0) {
-      code = -1;
-    }
-#endif
-  } else if (fetchOffsetNew.type == TMQ_OFFSET__SNAPSHOT_META) {
-    ASSERT(0);
   }
 
 OVER:
@@ -614,17 +597,8 @@ int32_t tqProcessVgChangeReq(STQ* pTq, char* msg, int32_t msgLen) {
   return 0;
 }
 
-int32_t tqProcessTaskDeployReq(STQ* pTq, char* msg, int32_t msgLen) {
+int32_t tqExpandTask(STQ* pTq, SStreamTask* pTask) {
-  SStreamTask* pTask = taosMemoryCalloc(1, sizeof(SStreamTask));
+  int32_t code = 0;
-  if (pTask == NULL) {
-    return -1;
-  }
-  SDecoder decoder;
-  tDecoderInit(&decoder, (uint8_t*)msg, msgLen);
-  if (tDecodeSStreamTask(&decoder, pTask) < 0) {
-    ASSERT(0);
-  }
-  tDecoderClear(&decoder);
   ASSERT(pTask->isDataScan == 0 || pTask->isDataScan == 1);
   if (pTask->isDataScan == 0 && pTask->sinkType == TASK_SINK__NONE) {
     ASSERT(taosArrayGetSize(pTask->childEpInfo) != 0);
@@ -634,11 +608,15 @@ int32_t tqProcessTaskDeployReq(STQ* pTq, char* msg, int32_t msgLen) {
 
   pTask->inputQueue = streamQueueOpen();
   pTask->outputQueue = streamQueueOpen();
+
+  if (pTask->inputQueue == NULL || pTask->outputQueue == NULL) {
+    code = -1;
+    goto FAIL;
+  }
+
   pTask->inputStatus = TASK_INPUT_STATUS__NORMAL;
   pTask->outputStatus = TASK_OUTPUT_STATUS__NORMAL;
 
-  if (pTask->inputQueue == NULL || pTask->outputQueue == NULL) goto FAIL;
-
   pTask->pMsgCb = &pTq->pVnode->msgCb;
 
   // exec
@@ -683,15 +661,35 @@ int32_t tqProcessTaskDeployReq(STQ* pTq, char* msg, int32_t msgLen) {
   tqInfo("deploy stream task on vg %d, task id %d, child id %d", TD_VID(pTq->pVnode), pTask->taskId,
          pTask->selfChildId);
 
-  taosHashPut(pTq->pStreamTasks, &pTask->taskId, sizeof(int32_t), &pTask, sizeof(void*));
-
-  /*SMeta* pMeta = pTq->pVnode->pMeta;*/
-  /*tdbTbUpsert(pMeta->pTaskIdx, &pTask->taskId, sizeof(int32_t), msg, msgLen, &pMeta->txn);*/
-
-  return 0;
 FAIL:
   if (pTask->inputQueue) streamQueueClose(pTask->inputQueue);
   if (pTask->outputQueue) streamQueueClose(pTask->outputQueue);
+  // TODO free executor
+  return code;
+}
+
+int32_t tqProcessTaskDeployReq(STQ* pTq, char* msg, int32_t msgLen) {
+  SStreamTask* pTask = taosMemoryCalloc(1, sizeof(SStreamTask));
+  if (pTask == NULL) {
+    return -1;
+  }
+  SDecoder decoder;
+  tDecoderInit(&decoder, (uint8_t*)msg, msgLen);
+  if (tDecodeSStreamTask(&decoder, pTask) < 0) {
+    ASSERT(0);
+    goto FAIL;
+  }
+  tDecoderClear(&decoder);
+
+  if (tqExpandTask(pTq, pTask) < 0) {
+    goto FAIL;
+  }
+
+  taosHashPut(pTq->pStreamTasks, &pTask->taskId, sizeof(int32_t), &pTask, sizeof(void*));
+
+  return 0;
+
+FAIL:
   if (pTask) taosMemoryFree(pTask);
   return -1;
 }
@@ -752,7 +750,7 @@ int32_t tqProcessTaskRunReq(STQ* pTq, SRpcMsg* pMsg) {
   }
 }
 
-int32_t tqProcessTaskDispatchReq(STQ* pTq, SRpcMsg* pMsg) {
+int32_t tqProcessTaskDispatchReq(STQ* pTq, SRpcMsg* pMsg, bool exec) {
   char*              msgStr = pMsg->pCont;
   char*              msgBody = POINTER_SHIFT(msgStr, sizeof(SMsgHead));
   int32_t            msgLen = pMsg->contLen - sizeof(SMsgHead);
@@ -767,7 +765,7 @@ int32_t tqProcessTaskDispatchReq(STQ* pTq, SRpcMsg* pMsg) {
         .info = pMsg->info,
         .code = 0,
     };
-    streamProcessDispatchReq(*ppTask, &req, &rsp);
+    streamProcessDispatchReq(*ppTask, &req, &rsp, exec);
     return 0;
   } else {
     return -1;
@@ -825,16 +823,6 @@ int32_t tqProcessTaskDropReq(STQ* pTq, char* msg, int32_t msgLen) {
   // launch exec to free memory
   // remove from hash
   return 0;
-
-#if 0
-  int32_t              code = taosHashRemove(pTq->pStreamTasks, &pReq->taskId, sizeof(int32_t));
-  // set status dropping
-  ASSERT(code == 0);
-  if (code == 0) {
-    // sendrsp
-  }
-  return code;
-#endif
 }
 
 int32_t tqProcessTaskRetrieveReq(STQ* pTq, SRpcMsg* pMsg) {
@@ -863,3 +851,37 @@ int32_t tqProcessTaskRetrieveRsp(STQ* pTq, SRpcMsg* pMsg) {
   //
   return 0;
 }
+
+void vnodeEnqueueStreamMsg(SVnode* pVnode, SRpcMsg* pMsg) {
+  STQ*    pTq = pVnode->pTq;
+  char*   msgStr = pMsg->pCont;
+  char*   msgBody = POINTER_SHIFT(msgStr, sizeof(SMsgHead));
+  int32_t msgLen = pMsg->contLen - sizeof(SMsgHead);
+  int32_t code = 0;
+
+  SStreamDispatchReq req;
+  SDecoder           decoder;
+  tDecoderInit(&decoder, msgBody, msgLen);
+  if (tDecodeStreamDispatchReq(&decoder, &req) < 0) {
+    code = TSDB_CODE_MSG_DECODE_ERROR;
+    goto FAIL;
+  }
+
+  int32_t       taskId = req.taskId;
+  SStreamTask** ppTask = (SStreamTask**)taosHashGet(pTq->pStreamTasks, &taskId, sizeof(int32_t));
+  if (ppTask) {
+    SRpcMsg rsp = {
+        .info = pMsg->info,
+        .code = 0,
+    };
+    streamProcessDispatchReq(*ppTask, &req, &rsp, false);
+    return;
+  }
+FAIL:
+  if (pMsg->info.handle == NULL) return;
+  SRpcMsg rsp = {
+      .code = code,
+      .info = pMsg->info,
+  };
+  tmsgSendRsp(&rsp);
+}

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

@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "meta.h"
+#include "tdbInt.h"
+#include "tq.h"
+
+// STqSnapReader ========================================
+struct STqSnapReader {
+  STQ*    pTq;
+  int64_t sver;
+  int64_t ever;
+  TBC*    pCur;
+};
+
+int32_t tqSnapReaderOpen(STQ* pTq, int64_t sver, int64_t ever, STqSnapReader** ppReader) {
+  int32_t        code = 0;
+  STqSnapReader* pReader = NULL;
+
+  // alloc
+  pReader = (STqSnapReader*)taosMemoryCalloc(1, sizeof(STqSnapReader));
+  if (pReader == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+  pReader->pTq = pTq;
+  pReader->sver = sver;
+  pReader->ever = ever;
+
+  // impl
+  code = tdbTbcOpen(pTq->pExecStore, &pReader->pCur, NULL);
+  if (code) {
+    taosMemoryFree(pReader);
+    goto _err;
+  }
+
+  code = tdbTbcMoveToFirst(pReader->pCur);
+  if (code) {
+    taosMemoryFree(pReader);
+    goto _err;
+  }
+
+  tqInfo("vgId:%d vnode snapshot tq reader opened", TD_VID(pTq->pVnode));
+
+  *ppReader = pReader;
+  return code;
+
+_err:
+  tqError("vgId:%d vnode snapshot tq reader open failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  *ppReader = NULL;
+  return code;
+}
+
+int32_t tqSnapReaderClose(STqSnapReader** ppReader) {
+  int32_t code = 0;
+
+  tdbTbcClose((*ppReader)->pCur);
+  taosMemoryFree(*ppReader);
+  *ppReader = NULL;
+
+  return code;
+}
+
+int32_t tqSnapRead(STqSnapReader* pReader, uint8_t** ppData) {
+  int32_t     code = 0;
+  const void* pKey = NULL;
+  const void* pVal = NULL;
+  int32_t     kLen = 0;
+  int32_t     vLen = 0;
+  SDecoder    decoder;
+  STqHandle   handle;
+
+  *ppData = NULL;
+  for (;;) {
+    if (tdbTbcGet(pReader->pCur, &pKey, &kLen, &pVal, &vLen)) {
+      goto _exit;
+    }
+
+    tDecoderInit(&decoder, (uint8_t*)pVal, vLen);
+    tDecodeSTqHandle(&decoder, &handle);
+    tDecoderClear(&decoder);
+
+    if (handle.snapshotVer <= pReader->sver && handle.snapshotVer >= pReader->ever) {
+      tdbTbcMoveToNext(pReader->pCur);
+      break;
+    } else {
+      tdbTbcMoveToNext(pReader->pCur);
+    }
+  }
+
+  ASSERT(pVal && vLen);
+
+  *ppData = taosMemoryMalloc(sizeof(SSnapDataHdr) + vLen);
+  if (*ppData == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+
+  SSnapDataHdr* pHdr = (SSnapDataHdr*)(*ppData);
+  pHdr->type = SNAP_DATA_TQ_HANDLE;
+  pHdr->size = vLen;
+  memcpy(pHdr->data, pVal, vLen);
+
+  tqInfo("vgId:%d vnode snapshot tq read data, version:%" PRId64 " subKey: %s vLen:%d", TD_VID(pReader->pTq->pVnode),
+         handle.snapshotVer, handle.subKey, vLen);
+
+_exit:
+  return code;
+
+_err:
+  tqError("vgId:%d vnode snapshot tq read data failed since %s", TD_VID(pReader->pTq->pVnode), tstrerror(code));
+  return code;
+}
+
+// STqSnapWriter ========================================
+struct STqSnapWriter {
+  STQ*    pTq;
+  int64_t sver;
+  int64_t ever;
+  TXN     txn;
+};
+
+int32_t tqSnapWriterOpen(STQ* pTq, int64_t sver, int64_t ever, STqSnapWriter** ppWriter) {
+  int32_t        code = 0;
+  STqSnapWriter* pWriter;
+
+  // alloc
+  pWriter = (STqSnapWriter*)taosMemoryCalloc(1, sizeof(*pWriter));
+  if (pWriter == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+  pWriter->pTq = pTq;
+  pWriter->sver = sver;
+  pWriter->ever = ever;
+
+  if (tdbTxnOpen(&pWriter->txn, 0, tdbDefaultMalloc, tdbDefaultFree, NULL, 0) < 0) {
+    ASSERT(0);
+  }
+
+  *ppWriter = pWriter;
+  return code;
+
+_err:
+  tqError("vgId:%d tq snapshot writer open failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  *ppWriter = NULL;
+  return code;
+}
+
+int32_t tqSnapWriterClose(STqSnapWriter** ppWriter, int8_t rollback) {
+  int32_t        code = 0;
+  STqSnapWriter* pWriter = *ppWriter;
+  STQ*           pTq = pWriter->pTq;
+
+  if (rollback) {
+    ASSERT(0);
+  } else {
+    code = tdbCommit(pWriter->pTq->pMetaStore, &pWriter->txn);
+    if (code) goto _err;
+  }
+
+  taosMemoryFree(pWriter);
+  *ppWriter = NULL;
+
+  // restore from metastore
+  if (tqMetaRestoreHandle(pTq) < 0) {
+    goto _err;
+  }
+
+  return code;
+
+_err:
+  tqError("vgId:%d tq snapshot writer close failed since %s", TD_VID(pWriter->pTq->pVnode), tstrerror(code));
+  return code;
+}
+
+int32_t tqSnapWrite(STqSnapWriter* pWriter, uint8_t* pData, uint32_t nData) {
+  int32_t   code = 0;
+  STQ*      pTq = pWriter->pTq;
+  SDecoder  decoder = {0};
+  SDecoder* pDecoder = &decoder;
+  STqHandle handle;
+
+  tDecoderInit(pDecoder, pData + sizeof(SSnapDataHdr), nData - sizeof(SSnapDataHdr));
+  code = tDecodeSTqHandle(pDecoder, &handle);
+  if (code) goto _err;
+  code = tqMetaSaveHandle(pTq, handle.subKey, &handle);
+  if (code < 0) goto _err;
+  tDecoderClear(pDecoder);
+
+  return code;
+
+_err:
+  tDecoderClear(pDecoder);
+  tqError("vgId:%d vnode snapshot tq write failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  return code;
+}

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

@@ -0,0 +1,209 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "meta.h"
+#include "tdbInt.h"
+#include "tq.h"
+
+// STqSnapReader ========================================
+struct STqSnapReader {
+  STQ*    pTq;
+  int64_t sver;
+  int64_t ever;
+  TBC*    pCur;
+};
+
+int32_t tqSnapReaderOpen(STQ* pTq, int64_t sver, int64_t ever, STqSnapReader** ppReader) {
+  int32_t        code = 0;
+  STqSnapReader* pReader = NULL;
+
+  // alloc
+  pReader = (STqSnapReader*)taosMemoryCalloc(1, sizeof(STqSnapReader));
+  if (pReader == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+  pReader->pTq = pTq;
+  pReader->sver = sver;
+  pReader->ever = ever;
+
+  // impl
+  code = tdbTbcOpen(pTq->pExecStore, &pReader->pCur, NULL);
+  if (code) {
+    taosMemoryFree(pReader);
+    goto _err;
+  }
+
+  code = tdbTbcMoveToFirst(pReader->pCur);
+  if (code) {
+    taosMemoryFree(pReader);
+    goto _err;
+  }
+
+  tqInfo("vgId:%d vnode snapshot tq reader opened", TD_VID(pTq->pVnode));
+
+  *ppReader = pReader;
+  return code;
+
+_err:
+  tqError("vgId:%d vnode snapshot tq reader open failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  *ppReader = NULL;
+  return code;
+}
+
+int32_t tqSnapReaderClose(STqSnapReader** ppReader) {
+  int32_t code = 0;
+
+  tdbTbcClose((*ppReader)->pCur);
+  taosMemoryFree(*ppReader);
+  *ppReader = NULL;
+
+  return code;
+}
+
+int32_t tqSnapRead(STqSnapReader* pReader, uint8_t** ppData) {
+  int32_t     code = 0;
+  const void* pKey = NULL;
+  const void* pVal = NULL;
+  int32_t     kLen = 0;
+  int32_t     vLen = 0;
+  SDecoder    decoder;
+  STqHandle   handle;
+
+  *ppData = NULL;
+  for (;;) {
+    if (tdbTbcGet(pReader->pCur, &pKey, &kLen, &pVal, &vLen)) {
+      goto _exit;
+    }
+
+    tDecoderInit(&decoder, (uint8_t*)pVal, vLen);
+    tDecodeSTqHandle(&decoder, &handle);
+    tDecoderClear(&decoder);
+
+    if (handle.snapshotVer <= pReader->sver && handle.snapshotVer >= pReader->ever) {
+      tdbTbcMoveToNext(pReader->pCur);
+      break;
+    } else {
+      tdbTbcMoveToNext(pReader->pCur);
+    }
+  }
+
+  ASSERT(pVal && vLen);
+
+  *ppData = taosMemoryMalloc(sizeof(SSnapDataHdr) + vLen);
+  if (*ppData == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+
+  SSnapDataHdr* pHdr = (SSnapDataHdr*)(*ppData);
+  pHdr->type = SNAP_DATA_TQ_HANDLE;
+  pHdr->size = vLen;
+  memcpy(pHdr->data, pVal, vLen);
+
+  tqInfo("vgId:%d vnode snapshot tq read data, version:%" PRId64 " subKey: %s vLen:%d", TD_VID(pReader->pTq->pVnode),
+         handle.snapshotVer, handle.subKey, vLen);
+
+_exit:
+  return code;
+
+_err:
+  tqError("vgId:%d vnode snapshot tq read data failed since %s", TD_VID(pReader->pTq->pVnode), tstrerror(code));
+  return code;
+}
+
+// STqSnapWriter ========================================
+struct STqSnapWriter {
+  STQ*    pTq;
+  int64_t sver;
+  int64_t ever;
+  TXN     txn;
+};
+
+int32_t tqSnapWriterOpen(STQ* pTq, int64_t sver, int64_t ever, STqSnapWriter** ppWriter) {
+  int32_t        code = 0;
+  STqSnapWriter* pWriter;
+
+  // alloc
+  pWriter = (STqSnapWriter*)taosMemoryCalloc(1, sizeof(*pWriter));
+  if (pWriter == NULL) {
+    code = TSDB_CODE_OUT_OF_MEMORY;
+    goto _err;
+  }
+  pWriter->pTq = pTq;
+  pWriter->sver = sver;
+  pWriter->ever = ever;
+
+  if (tdbTxnOpen(&pWriter->txn, 0, tdbDefaultMalloc, tdbDefaultFree, NULL, 0) < 0) {
+    ASSERT(0);
+  }
+
+  *ppWriter = pWriter;
+  return code;
+
+_err:
+  tqError("vgId:%d tq snapshot writer open failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  *ppWriter = NULL;
+  return code;
+}
+
+int32_t tqSnapWriterClose(STqSnapWriter** ppWriter, int8_t rollback) {
+  int32_t        code = 0;
+  STqSnapWriter* pWriter = *ppWriter;
+  STQ*           pTq = pWriter->pTq;
+
+  if (rollback) {
+    ASSERT(0);
+  } else {
+    code = tdbCommit(pWriter->pTq->pMetaStore, &pWriter->txn);
+    if (code) goto _err;
+  }
+
+  taosMemoryFree(pWriter);
+  *ppWriter = NULL;
+
+  // restore from metastore
+  if (tqMetaRestoreHandle(pTq) < 0) {
+    goto _err;
+  }
+
+  return code;
+
+_err:
+  tqError("vgId:%d tq snapshot writer close failed since %s", TD_VID(pWriter->pTq->pVnode), tstrerror(code));
+  return code;
+}
+
+int32_t tqSnapWrite(STqSnapWriter* pWriter, uint8_t* pData, uint32_t nData) {
+  int32_t   code = 0;
+  STQ*      pTq = pWriter->pTq;
+  SDecoder  decoder = {0};
+  SDecoder* pDecoder = &decoder;
+  STqHandle handle;
+
+  tDecoderInit(pDecoder, pData + sizeof(SSnapDataHdr), nData - sizeof(SSnapDataHdr));
+  code = tDecodeSTqHandle(pDecoder, &handle);
+  if (code) goto _err;
+  code = tqMetaSaveHandle(pTq, handle.subKey, &handle);
+  if (code < 0) goto _err;
+  tDecoderClear(pDecoder);
+
+  return code;
+
+_err:
+  tDecoderClear(pDecoder);
+  tqError("vgId:%d vnode snapshot tq write failed since %s", TD_VID(pTq->pVnode), tstrerror(code));
+  return code;
+}

source/dnode/vnode/src/vnd/vnodeSvr.c

@@ -297,8 +297,8 @@ int32_t vnodeProcessQueryMsg(SVnode *pVnode, SRpcMsg *pMsg) {
 
 int32_t vnodeProcessFetchMsg(SVnode *pVnode, SRpcMsg *pMsg, SQueueInfo *pInfo) {
   vTrace("message in fetch queue is processing");
-  if ((pMsg->msgType == TDMT_SCH_FETCH || pMsg->msgType == TDMT_VND_TABLE_META ||
+  if ((pMsg->msgType == TDMT_SCH_FETCH || pMsg->msgType == TDMT_VND_TABLE_META || pMsg->msgType == TDMT_VND_TABLE_CFG ||
-       pMsg->msgType == TDMT_VND_TABLE_CFG || pMsg->msgType == TDMT_VND_BATCH_META) &&
+       pMsg->msgType == TDMT_VND_BATCH_META) &&
       !vnodeIsLeader(pVnode)) {
     vnodeRedirectRpcMsg(pVnode, pMsg);
     return 0;
@@ -330,7 +330,7 @@ int32_t vnodeProcessFetchMsg(SVnode *pVnode, SRpcMsg *pMsg, SQueueInfo *pInfo) {
     case TDMT_STREAM_TASK_RUN:
       return tqProcessTaskRunReq(pVnode->pTq, pMsg);
     case TDMT_STREAM_TASK_DISPATCH:
-      return tqProcessTaskDispatchReq(pVnode->pTq, pMsg);
+      return tqProcessTaskDispatchReq(pVnode->pTq, pMsg, true);
     case TDMT_STREAM_TASK_RECOVER:
       return tqProcessTaskRecoverReq(pVnode->pTq, pMsg);
     case TDMT_STREAM_RETRIEVE:

source/libs/stream/CMakeLists.txt

@@ -8,7 +8,7 @@ target_include_directories(
 
 target_link_libraries(
     stream
-    PRIVATE os util transport qcom executor
+    PRIVATE os util transport qcom executor tdb
 )
 
 if(${BUILD_TEST})

source/libs/stream/src/stream.c

@@ -175,41 +175,22 @@ int32_t streamTaskEnqueueRetrieve(SStreamTask* pTask, SStreamRetrieveReq* pReq,
   return status == TASK_INPUT_STATUS__NORMAL ? 0 : -1;
 }
 
-int32_t streamProcessDispatchReq(SStreamTask* pTask, SStreamDispatchReq* pReq, SRpcMsg* pRsp) {
+int32_t streamProcessDispatchReq(SStreamTask* pTask, SStreamDispatchReq* pReq, SRpcMsg* pRsp, bool exec) {
   qDebug("task %d receive dispatch req from node %d task %d", pTask->taskId, pReq->upstreamNodeId,
          pReq->upstreamTaskId);
 
-  // 1. handle input
   streamTaskEnqueue(pTask, pReq, pRsp);
 
-  // 2. try exec
+  if (exec) {
-  // 2.1. idle: exec
-  // 2.2. executing: return
-  // 2.3. closing: keep trying
-#if 0
-  if (pTask->execType != TASK_EXEC__NONE) {
-#endif
     streamExec(pTask);
-#if 0
-  } else {
-    ASSERT(pTask->sinkType != TASK_SINK__NONE);
-    while (1) {
-      void* data = streamQueueNextItem(pTask->inputQueue);
-      if (data == NULL) return 0;
-      if (streamTaskOutput(pTask, data) < 0) {
-        ASSERT(0);
-      }
-    }
-  }
-#endif
 
-  // 3. handle output
-  // 3.1 check and set status
-  // 3.2 dispatch / sink
     if (pTask->dispatchType != TASK_DISPATCH__NONE) {
       ASSERT(pTask->sinkType == TASK_SINK__NONE);
       streamDispatch(pTask);
     }
+  } else {
+    streamLaunchByWrite(pTask, pTask->nodeId);
+  }
 
   return 0;
 }

source/libs/stream/src/streamMeta.c

@@ -0,0 +1,159 @@
+/*
+ * Copyright (c) 2019 TAOS Data, Inc. <jhtao@taosdata.com>
+ *
+ * This program is free software: you can use, redistribute, and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3
+ * or later ("AGPL"), as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "executor.h"
+#include "tdbInt.h"
+#include "tstream.h"
+
+typedef int32_t FTaskExpand(void* ahandle, SStreamTask* pTask);
+
+typedef struct SStreamMeta {
+  char*        path;
+  TDB*         db;
+  TTB*         pTaskDb;
+  TTB*         pStateDb;
+  SHashObj*    pTasks;
+  void*        ahandle;
+  TXN          txn;
+  FTaskExpand* expandFunc;
+} SStreamMeta;
+
+SStreamMeta* streamMetaOpen(const char* path, void* ahandle, FTaskExpand expandFunc) {
+  SStreamMeta* pMeta = taosMemoryCalloc(1, sizeof(SStreamMeta));
+  if (pMeta == NULL) {
+    terrno = TSDB_CODE_OUT_OF_MEMORY;
+    return NULL;
+  }
+  pMeta->path = strdup(path);
+  if (tdbOpen(pMeta->path, 16 * 1024, 1, &pMeta->db) < 0) {
+    goto _err;
+  }
+
+  if (tdbTbOpen("task.db", sizeof(int32_t), -1, NULL, pMeta->db, &pMeta->pTaskDb) < 0) {
+    goto _err;
+  }
+
+  // open state storage backend
+  if (tdbTbOpen("state.db", sizeof(int32_t), -1, NULL, pMeta->db, &pMeta->pStateDb) < 0) {
+    goto _err;
+  }
+
+  pMeta->ahandle = ahandle;
+  pMeta->expandFunc = expandFunc;
+
+_err:
+
+  return NULL;
+}
+
+void streamMetaClose(SStreamMeta* pMeta) {
+  //
+  return;
+}
+
+int32_t streamMetaAddTask(SStreamMeta* pMeta, SStreamTask* pTask) {
+  void* buf = NULL;
+  if (pMeta->expandFunc(pMeta->ahandle, pTask) < 0) {
+    return -1;
+  }
+  taosHashPut(pMeta->pTasks, &pTask->taskId, sizeof(int32_t), &pTask, sizeof(void*));
+
+  int32_t len;
+  int32_t code;
+  tEncodeSize(tEncodeSStreamTask, pTask, len, code);
+  if (code < 0) {
+    return -1;
+  }
+  buf = taosMemoryCalloc(1, sizeof(len));
+  if (buf == NULL) {
+    return -1;
+  }
+
+  SEncoder encoder;
+  tEncoderInit(&encoder, buf, len);
+  tEncodeSStreamTask(&encoder, pTask);
+
+  if (tdbTbUpsert(pMeta->pTaskDb, &pTask->taskId, sizeof(int32_t), buf, len, &pMeta->txn) < 0) {
+    ASSERT(0);
+    return -1;
+  }
+
+  return 0;
+}
+
+int32_t streamMetaRemoveTask(SStreamMeta* pMeta, int32_t taskId) {
+  SStreamTask** ppTask = (SStreamTask**)taosHashGet(pMeta->pTasks, &taskId, sizeof(int32_t));
+  if (ppTask) {
+    SStreamTask* pTask = *ppTask;
+    taosHashRemove(pMeta->pTasks, &taskId, sizeof(int32_t));
+    atomic_store_8(&pTask->taskStatus, TASK_STATUS__DROPPING);
+  }
+
+  if (tdbTbDelete(pMeta->pTaskDb, &taskId, sizeof(int32_t), &pMeta->txn) < 0) {
+    /*return -1;*/
+  }
+  return 0;
+}
+
+int32_t streamMetaBegin(SStreamMeta* pMeta) {
+  if (tdbTxnOpen(&pMeta->txn, 0, tdbDefaultMalloc, tdbDefaultFree, NULL, TDB_TXN_WRITE | TDB_TXN_READ_UNCOMMITTED) <
+      0) {
+    return -1;
+  }
+
+  if (tdbBegin(pMeta->db, &pMeta->txn) < 0) {
+    return -1;
+  }
+  return 0;
+}
+
+int32_t streamMetaCommit(SStreamMeta* pMeta) {
+  if (tdbCommit(pMeta->db, &pMeta->txn) < 0) {
+    return -1;
+  }
+  return 0;
+}
+
+int32_t streamMetaRollBack(SStreamMeta* pMeta) {
+  // TODO tdb rollback
+  return 0;
+}
+int32_t streamRestoreTask(SStreamMeta* pMeta) {
+  TBC* pCur = NULL;
+  if (tdbTbcOpen(pMeta->pTaskDb, &pCur, NULL) < 0) {
+    ASSERT(0);
+    return -1;
+  }
+
+  void*    pKey = NULL;
+  int32_t  kLen = 0;
+  void*    pVal = NULL;
+  int32_t  vLen = 0;
+  SDecoder decoder;
+
+  tdbTbcMoveToFirst(pCur);
+
+  while (tdbTbcNext(pCur, &pKey, &kLen, &pVal, &vLen) == 0) {
+    SStreamTask* pTask = taosMemoryCalloc(1, sizeof(SStreamTask));
+    if (pTask == NULL) {
+      return -1;
+    }
+    tDecoderInit(&decoder, (uint8_t*)pVal, vLen);
+    tDecodeSStreamTask(&decoder, pTask);
+    tDecoderClear(&decoder);
+  }
+
+  return 0;
+}