show table rules (arana-db#760)

pkg/executor/redirect.go

@@ -280,8 +280,9 @@ func (executor *RedirectExecutor) doExecutorComQuery(ctx *proto.Context, act ast
 		allowSchemaless := func(stmt *ast.ShowStmt) bool {
 			switch stmt.Tp {
 			case ast.ShowDatabases, ast.ShowVariables, ast.ShowTopology, ast.ShowStatus, ast.ShowTableStatus,
-				ast.ShowWarnings, ast.ShowCharset, ast.ShowMasterStatus, ast.ShowProcessList, ast.ShowReplicas, ast.ShowShardingTable,
-				ast.ShowReplicaStatus, ast.ShowNodes, ast.ShowUsers, ast.ShowCreateSequence, ast.ShowDatabaseRules:
+				ast.ShowWarnings, ast.ShowCharset, ast.ShowMasterStatus, ast.ShowProcessList, ast.ShowReplicas,
+				ast.ShowShardingTable, ast.ShowReplicaStatus, ast.ShowNodes, ast.ShowUsers, ast.ShowCreateSequence,
+				ast.ShowDatabaseRules, ast.ShowTableRules:
 				return true
 			default:
 				return false

pkg/mysql/thead/thead.go

@@ -70,6 +70,14 @@ var (
 		Col{Name: "expr", FieldType: consts.FieldTypeVarString},
 		Col{Name: "step", FieldType: consts.FieldTypeInt24},
 	}
+
+	TableRule = Thead{
+		Col{Name: "table_name", FieldType: consts.FieldTypeVarString},
+		Col{Name: "column", FieldType: consts.FieldTypeVarString},
+		Col{Name: "type", FieldType: consts.FieldTypeVarString},
+		Col{Name: "expr", FieldType: consts.FieldTypeVarString},
+		Col{Name: "step", FieldType: consts.FieldTypeVarString},
+	}
 )
 
 type Col struct {

pkg/runtime/ast/ast.go

@@ -754,6 +754,8 @@ func (cc *convCtx) convShowStmt(node *ast.ShowStmt) Statement {
 			pattern.String = like
 		}
 		return &ShowDatabases{BaseShowWithSingleColumn: &BaseShowWithSingleColumn{toBaseShow(), pattern}}
+	case ast.ShowTableRules:
+		return &ShowTableRule{BaseShow: toBaseShow(), Database: node.DBName, TableName: node.Table.Name.String()}
 	case ast.ShowDatabaseRules:
 		return &ShowDatabaseRule{BaseShow: toBaseShow(), Database: node.DBName, TableName: node.Table.Name.String()}
 	case ast.ShowCollation:

pkg/runtime/ast/proto.go

@@ -68,6 +68,7 @@ const (
 	SQLTypeRepairTable                // REPAIR TABLE
 	SQLTypeCreateTable                // CREATE TABLE
 	SQLTypeShowDatabaseRules          // SHOW DATABASE RULES
+	SQLTypeShowTableRules             // SHOW TABLE RULES
 )
 
 var _sqlTypeNames = [...]string{
@@ -108,6 +109,7 @@ var _sqlTypeNames = [...]string{
 	SQLTypeRepairTable:        "REPAIR TABLE",
 	SQLTypeCreateTable:        "CREATE TABLE",
 	SQLTypeShowDatabaseRules:  "SHOW DATABASE RULES",
+	SQLTypeShowTableRules:     "SHOW TABLE RULES",
 }
 
 // SQLType represents the type of SQL.

pkg/runtime/ast/show.go

@@ -670,14 +670,32 @@ type ShowDatabaseRule struct {
 	TableName string
 }
 
-func (s ShowDatabaseRule) Mode() SQLType {
+func (s *ShowDatabaseRule) Mode() SQLType {
 	return SQLTypeShowDatabaseRules
 }
 
-func (s ShowDatabaseRule) Restore(flag RestoreFlag, sb *strings.Builder, args *[]int) error {
+func (s *ShowDatabaseRule) Restore(flag RestoreFlag, sb *strings.Builder, args *[]int) error {
 	sb.WriteString("SHOW DATABASE RULES ")
 	if err := s.BaseShow.Restore(flag, sb, args); err != nil {
 		return errors.WithStack(err)
 	}
 	return nil
 }
+
+type ShowTableRule struct {
+	*BaseShow
+	Database  string
+	TableName string
+}
+
+func (s *ShowTableRule) Mode() SQLType {
+	return SQLTypeShowTableRules
+}
+
+func (s *ShowTableRule) Restore(flag RestoreFlag, sb *strings.Builder, args *[]int) error {
+	sb.WriteString("SHOW TABLE RULES ")
+	if err := s.BaseShow.Restore(flag, sb, args); err != nil {
+		return errors.WithStack(err)
+	}
+	return nil
+}

pkg/runtime/optimize/dal/show_table_rule.go

@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dal
+
+import (
+	"context"
+)
+
+import (
+	"github.com/arana-db/arana/pkg/proto"
+	"github.com/arana-db/arana/pkg/runtime/ast"
+	"github.com/arana-db/arana/pkg/runtime/optimize"
+	"github.com/arana-db/arana/pkg/runtime/plan/dal"
+)
+
+func init() {
+	optimize.Register(ast.SQLTypeShowTableRules, optimizeShowTableRules)
+}
+
+func optimizeShowTableRules(_ context.Context, o *optimize.Optimizer) (proto.Plan, error) {
+	rule := o.Rule
+	stmt := o.Stmt.(*ast.ShowTableRule)
+	ret := dal.NewShowTableRulesPlan(stmt)
+	ret.BindArgs(o.Args)
+	ret.SetRule(rule)
+	return ret, nil
+}

pkg/runtime/plan/dal/show_database_rules.go

@@ -55,22 +55,24 @@ func (s *ShowDatabaseRulesPlan) ExecIn(ctx context.Context, _ proto.VConn) (prot
 		Columns: fields,
 	}
 
-	if vt, ok := s.rule.VTable(s.Stmt.TableName); ok {
-		for _, vs := range vt.GetVShards() {
-			var columns []string
-			for i := range vs.DB.ShardColumns {
-				columns = append(columns, vs.DB.ShardColumns[i].Name)
-			}
-			ds.Rows = append(ds.Rows, rows.NewTextVirtualRow(fields, []proto.Value{
-				proto.NewValueString(s.Stmt.TableName),
-				proto.NewValueString(strings.Join(columns, ",")),
-				proto.NewValueString(""),
-				proto.NewValueString(fmt.Sprintf("%s", vs.DB.Computer)),
-				proto.NewValueInt64(1),
-			}))
-		}
+	vt, ok := s.rule.VTable(s.Stmt.TableName)
+	if !ok {
+		return resultx.New(resultx.WithDataset(ds)), nil
 	}
 
+	for _, vs := range vt.GetVShards() {
+		var columns []string
+		for i := range vs.DB.ShardColumns {
+			columns = append(columns, vs.DB.ShardColumns[i].Name)
+		}
+		ds.Rows = append(ds.Rows, rows.NewTextVirtualRow(fields, []proto.Value{
+			proto.NewValueString(s.Stmt.TableName),
+			proto.NewValueString(strings.Join(columns, ",")),
+			proto.NewValueString(""),
+			proto.NewValueString(fmt.Sprintf("%s", vs.DB.Computer)),
+			proto.NewValueInt64(1),
+		}))
+	}
 	return resultx.New(resultx.WithDataset(ds)), nil
 }
 

pkg/runtime/plan/dal/show_table_rules.go

@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dal
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+import (
+	"github.com/arana-db/arana/pkg/dataset"
+	"github.com/arana-db/arana/pkg/mysql/rows"
+	"github.com/arana-db/arana/pkg/mysql/thead"
+	"github.com/arana-db/arana/pkg/proto"
+	"github.com/arana-db/arana/pkg/proto/rule"
+	"github.com/arana-db/arana/pkg/resultx"
+	"github.com/arana-db/arana/pkg/runtime/ast"
+	"github.com/arana-db/arana/pkg/runtime/plan"
+)
+
+var _ proto.Plan = (*ShowTableRulesPlan)(nil)
+
+type ShowTableRulesPlan struct {
+	plan.BasePlan
+	Stmt *ast.ShowTableRule
+	rule *rule.Rule
+}
+
+func (s *ShowTableRulesPlan) Type() proto.PlanType {
+	return proto.PlanTypeQuery
+}
+
+func (s *ShowTableRulesPlan) ExecIn(ctx context.Context, _ proto.VConn) (proto.Result, error) {
+	_, span := plan.Tracer.Start(ctx, "ShowTableRulesPlan.ExecIn")
+	defer span.End()
+
+	fields := thead.TableRule.ToFields()
+	ds := &dataset.VirtualDataset{
+		Columns: fields,
+	}
+	vt, ok := s.rule.VTable(s.Stmt.TableName)
+	if !ok {
+		return resultx.New(resultx.WithDataset(ds)), nil
+	}
+
+	for _, vs := range vt.GetVShards() {
+		var (
+			columns []string
+			steps   []string
+		)
+
+		for i := range vs.Table.ShardColumns {
+			columns = append(columns, vs.Table.ShardColumns[i].Name)
+			steps = append(steps, strconv.Itoa(vs.Table.ShardColumns[i].Steps))
+		}
+
+		ds.Rows = append(ds.Rows, rows.NewTextVirtualRow(fields, []proto.Value{
+			proto.NewValueString(s.Stmt.TableName),
+			proto.NewValueString(strings.Join(columns, ",")),
+			proto.NewValueString(""),
+			proto.NewValueString(fmt.Sprintf("%s", vs.Table.Computer)),
+			proto.NewValueString(strings.Join(steps, ",")),
+		}))
+	}
+
+	return resultx.New(resultx.WithDataset(ds)), nil
+}
+
+func (s *ShowTableRulesPlan) SetRule(rule *rule.Rule) {
+	s.rule = rule
+}
+
+// NewShowTableRulesPlan create ShowTableRules Plan
+func NewShowTableRulesPlan(stmt *ast.ShowTableRule) *ShowTableRulesPlan {
+	return &ShowTableRulesPlan{
+		Stmt: stmt,
+	}
+}

test/integration_test.go

@@ -680,6 +680,39 @@ func (s *IntegrationSuite) TestShowDatabaseRules() {
 	}
 }
 
+func (s *IntegrationSuite) TestShowTableRules() {
+	var (
+		db = s.DB()
+		t  = s.T()
+	)
+
+	tests := []struct {
+		name      string
+		sql       string
+		expectNum int
+	}{
+		{
+			name:      "show table rules from employees",
+			sql:       "show table rules from employees",
+			expectNum: 0,
+		},
+		{
+			name:      "show table rules from student",
+			sql:       "show table rules from student",
+			expectNum: 1,
+		},
+	}
+
+	for _, v := range tests {
+		rows, err := db.Query(v.sql)
+		defer rows.Close()
+		assert.NoErrorf(t, err, "show table rules error: %v", err)
+		results, err := utils.PrintTable(rows)
+		assert.NoErrorf(t, err, "show table rules error: %v", err)
+		assert.Equal(t, len(results), v.expectNum)
+	}
+}
+
 func (s *IntegrationSuite) TestDropTrigger() {
 	var (
 		db = s.DB()