enh: add a field toVgId in vnodes.json for prepare alter-hashrange

source/dnode/mgmt/mgmt_vnode/inc/vmInt.h

@@ -46,6 +46,7 @@ typedef struct {
   int32_t vgId;
   int32_t vgVersion;
   int8_t  dropped;
+  int32_t toVgId;
   char    path[PATH_MAX + 20];
 } SWrapperCfg;
 
@@ -55,6 +56,7 @@ typedef struct {
   int32_t       refCount;
   int8_t        dropped;
   int8_t        disable;
+  int32_t       toVgId;
   char         *path;
   SVnode       *pImpl;
   SMultiWorker  pWriteW;

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

@@ -71,6 +71,8 @@ static int32_t vmDecodeVnodeList(SJson *pJson, SVnodeMgmt *pMgmt, SWrapperCfg **
     if (code < 0) goto _OVER;
     tjsonGetInt32ValueFromDouble(vnode, "vgVersion", pCfg->vgVersion, code);
     if (code < 0) goto _OVER;
+    tjsonGetInt32ValueFromDouble(vnode, "toVgId", pCfg->toVgId, code);
+    if (code < 0) goto _OVER;
 
     snprintf(pCfg->path, sizeof(pCfg->path), "%s%svnode%d", pMgmt->path, TD_DIRSEP, pCfg->vgId);
   }
@@ -165,6 +167,7 @@ static int32_t vmEncodeVnodeList(SJson *pJson, SVnodeObj **ppVnodes, int32_t num
     if (tjsonAddDoubleToObject(vnode, "vgId", pVnode->vgId) < 0) return -1;
     if (tjsonAddDoubleToObject(vnode, "dropped", pVnode->dropped) < 0) return -1;
     if (tjsonAddDoubleToObject(vnode, "vgVersion", pVnode->vgVersion) < 0) return -1;
+    if (pVnode->toVgId && tjsonAddDoubleToObject(vnode, "toVgId", pVnode->toVgId) < 0) return -1;
     if (tjsonAddItemToArray(vnodes, vnode) < 0) return -1;
   }
 
@@ -179,7 +182,7 @@ int32_t vmWriteVnodeListToFile(SVnodeMgmt *pMgmt) {
   SVnodeObj **ppVnodes = NULL;
   char        file[PATH_MAX] = {0};
   char        realfile[PATH_MAX] = {0};
-  snprintf(file, sizeof(file), "%s%svnodes.json.bak", pMgmt->path, TD_DIRSEP);
+  snprintf(file, sizeof(file), "%s%svnodes_tmp.json", pMgmt->path, TD_DIRSEP);
   snprintf(realfile, sizeof(realfile), "%s%svnodes.json", pMgmt->path, TD_DIRSEP);
 
   int32_t numOfVnodes = 0;

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

@@ -509,6 +509,13 @@ int32_t vmProcessAlterHashRangeReq(SVnodeMgmt *pMgmt, SRpcMsg *pMsg) {
   };
   tstrncpy(wrapperCfg.path, pVnode->path, sizeof(wrapperCfg.path));
 
+  // prepare alter
+  pVnode->toVgId = dstVgId;
+  if (vmWriteVnodeListToFile(pMgmt) != 0) {
+    dError("vgId:%d, failed to write vnode list since %s", dstVgId, terrstr());
+    return -1;
+  }
+
   dInfo("vgId:%d, close vnode", srcVgId);
   vmCloseVnode(pMgmt, pVnode, true);
 
@@ -540,6 +547,7 @@ int32_t vmProcessAlterHashRangeReq(SVnodeMgmt *pMgmt, SRpcMsg *pMsg) {
     return -1;
   }
 
+  // complete alter
   if (vmWriteVnodeListToFile(pMgmt) != 0) {
     dError("vgId:%d, failed to write vnode list since %s", dstVgId, terrstr());
     return -1;