http: add http api for get db and table info that is related to the t…

…ableID (#8256) (#9408)

docs/tidb_http_api.md

@@ -52,6 +52,12 @@
     curl http://{TiDBIP}:10080/schema?table_id={tableID}
     ```
 
+1. Get database information, table information and tidb info schema version by tableID.
+
+    ```shell
+    curl http://{TiDBIP}:10080/db-table/{tableID}
+    ```
+
 1. Get MVCC Information of the key with a specified handle ID
 
     ```shell

infoschema/infoschema.go

@@ -70,6 +70,7 @@ type InfoSchema interface {
 	TableByName(schema, table model.CIStr) (table.Table, error)
 	TableExists(schema, table model.CIStr) bool
 	SchemaByID(id int64) (*model.DBInfo, bool)
+	SchemaByTable(tableInfo *model.TableInfo) (*model.DBInfo, bool)
 	TableByID(id int64) (table.Table, bool)
 	AllocByID(id int64) (autoid.Allocator, bool)
 	AllSchemaNames() []string
@@ -194,6 +195,20 @@ func (is *infoSchema) SchemaByID(id int64) (val *model.DBInfo, ok bool) {
 	return nil, false
 }
 
+func (is *infoSchema) SchemaByTable(tableInfo *model.TableInfo) (val *model.DBInfo, ok bool) {
+	if tableInfo == nil {
+		return nil, false
+	}
+	for _, v := range is.schemaMap {
+		if tbl, ok := v.tables[tableInfo.Name.L]; ok {
+			if tbl.Meta().ID == tableInfo.ID {
+				return v.dbInfo, true
+			}
+		}
+	}
+	return nil, false
+}
+
 func (is *infoSchema) TableByID(id int64) (val table.Table, ok bool) {
 	slice := is.sortedTablesBuckets[tableBucketIdx(id)]
 	idx := slice.searchTable(id)

server/http_handler.go

@@ -61,6 +61,7 @@ const (
 	pRegionID   = "regionID"
 	pStartTS    = "startTS"
 	pTableName  = "table"
+	pTableID    = "tableID"
 	pColumnID   = "colID"
 	pColumnTp   = "colTp"
 	pColumnFlag = "colFlag"
@@ -317,6 +318,10 @@ type schemaHandler struct {
 	*tikvHandlerTool
 }
 
+type dbTableHandler struct {
+	*tikvHandlerTool
+}
+
 // regionHandler is the common field for http handler. It contains
 // some common functions for all handlers.
 type regionHandler struct {
@@ -1362,3 +1367,45 @@ func (h allServerInfoHandler) ServeHTTP(w http.ResponseWriter, req *http.Request
 	}
 	writeData(w, clusterInfo)
 }
+
+// dbTableInfo is used to report the database, table information and the current schema version.
+type dbTableInfo struct {
+	DBInfo        *model.DBInfo    `json:"db_info"`
+	TableInfo     *model.TableInfo `json:"table_info"`
+	SchemaVersion int64            `json:"schema_version"`
+}
+
+//ServeHTTP handles request of database information and table information by tableID.
+func (h dbTableHandler) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	params := mux.Vars(req)
+	tableID := params[pTableID]
+	tblID, err := strconv.Atoi(tableID)
+	if err != nil {
+		writeError(w, errors.Errorf("Wrong tableID: %v", tableID))
+		return
+	}
+
+	schema, err := h.schema()
+	if err != nil {
+		writeError(w, err)
+		return
+	}
+
+	dbTblInfo := dbTableInfo{
+		SchemaVersion: schema.SchemaMetaVersion(),
+	}
+	tbl, ok := schema.TableByID(int64(tblID))
+	if !ok {
+		writeError(w, infoschema.ErrTableNotExists.GenWithStack("Table which ID = %s does not exist.", tableID))
+		return
+	}
+	dbTblInfo.TableInfo = tbl.Meta()
+	dbInfo, ok := schema.SchemaByTable(dbTblInfo.TableInfo)
+	if !ok {
+		log.Warnf("can not find the database of table id: %v, table name: %v", dbTblInfo.TableInfo.ID, dbTblInfo.TableInfo.Name)
+		writeData(w, dbTblInfo)
+		return
+	}
+	dbTblInfo.DBInfo = dbInfo
+	writeData(w, dbTblInfo)
+}

server/http_handler_test.go

@@ -570,6 +570,18 @@ func (ts *HTTPHandlerTestSuite) TestGetSchema(c *C) {
 
 	_, err = http.Get(fmt.Sprintf("http://127.0.0.1:10090/schema/tidb/abc"))
 	c.Assert(err, IsNil)
+
+	resp, err = http.Get(fmt.Sprintf("http://127.0.0.1:10090/db-table/5"))
+	c.Assert(err, IsNil)
+	var dbtbl *dbTableInfo
+	decoder = json.NewDecoder(resp.Body)
+	err = decoder.Decode(&dbtbl)
+	c.Assert(err, IsNil)
+	c.Assert(dbtbl.TableInfo.Name.L, Equals, "user")
+	c.Assert(dbtbl.DBInfo.Name.L, Equals, "mysql")
+	se, err := session.CreateSession(ts.store.(kv.Storage))
+	c.Assert(err, IsNil)
+	c.Assert(dbtbl.SchemaVersion, Equals, domain.GetDomain(se.(sessionctx.Context)).InfoSchema().SchemaMetaVersion())
 }
 
 func (ts *HTTPHandlerTestSuite) TestAllHistory(c *C) {

server/http_status.go

@@ -58,6 +58,9 @@ func (s *Server) startHTTPServer() {
 	// HTTP path for get server info.
 	router.Handle("/info", serverInfoHandler{tikvHandlerTool})
 	router.Handle("/info/all", allServerInfoHandler{tikvHandlerTool})
+	// HTTP path for get db and table info that is related to the tableID.
+	router.Handle("/db-table/{tableID}", dbTableHandler{tikvHandlerTool})
+
 	if s.cfg.Store == "tikv" {
 		// HTTP path for tikv.
 		router.Handle("/tables/{db}/{table}/regions", tableHandler{tikvHandlerTool, opTableRegions})