executor, plan: add executor to support GRANT ROLE

executor/simple.go

@@ -56,6 +56,8 @@ func (e *SimpleExec) Next(ctx context.Context, req *chunk.RecordBatch) (err erro
 		return nil
 	}
 	switch x := e.Statement.(type) {
+	case *ast.GrantRoleStmt:
+		err = e.executeGrantRole(x)
 	case *ast.UseStmt:
 		err = e.executeUse(x)
 	case *ast.FlushStmt:
@@ -277,6 +279,52 @@ func (e *SimpleExec) executeAlterUser(s *ast.AlterUserStmt) error {
 	return nil
 }
 
+func (e *SimpleExec) executeGrantRole(s *ast.GrantRoleStmt) error {
+	failedUsers := make([]string, 0, len(s.Users))
+	for _, role := range s.Roles {
+		exists, err := userExists(e.ctx, role.Username, role.Hostname)
+		if err != nil {
+			return err
+		}
+		if !exists {
+			return ErrCannotUser.GenWithStackByArgs("GRANT ROLE", role.String())
+		}
+	}
+	for _, user := range s.Users {
+		exists, err := userExists(e.ctx, user.Username, user.Hostname)
+		if err != nil {
+			return err
+		}
+		if !exists {
+			return ErrCannotUser.GenWithStackByArgs("GRANT ROLE", user.String())
+		}
+	}
+
+	// begin a transaction to insert role graph edges.
+	if _, err := e.ctx.(sqlexec.SQLExecutor).Execute(context.Background(), "begin"); err != nil {
+		return err
+	}
+
+	for _, user := range s.Users {
+		for _, role := range s.Roles {
+			sql := fmt.Sprintf(`INSERT IGNORE INTO %s.%s (FROM_HOST, FROM_USER, TO_HOST, TO_USER) VALUES ('%s','%s','%s','%s')`, mysql.SystemDB, mysql.RoleEdgeTable, role.Hostname, role.Username, user.Hostname, user.Username)
+			if _, err := e.ctx.(sqlexec.SQLExecutor).Execute(context.Background(), sql); err != nil {
+				failedUsers = append(failedUsers, user.String())
+				logutil.Logger(context.Background()).Error(fmt.Sprintf("Error occur when executing %s", sql))
+				if _, err := e.ctx.(sqlexec.SQLExecutor).Execute(context.Background(), "rollback"); err != nil {
+					return err
+				}
+				return ErrCannotUser.GenWithStackByArgs("GRANT ROLE", user.String())
+			}
+		}
+	}
+	if _, err := e.ctx.(sqlexec.SQLExecutor).Execute(context.Background(), "commit"); err != nil {
+		return err
+	}
+	err := domain.GetDomain(e.ctx).PrivilegeHandle().Update(e.ctx.(sessionctx.Context))
+	return err
+}
+
 func (e *SimpleExec) executeDropUser(s *ast.DropUserStmt) error {
 	failedUsers := make([]string, 0, len(s.UserList))
 	for _, user := range s.UserList {

executor/simple_test.go

@@ -93,6 +93,7 @@ func (s *testSuite3) TestRole(c *C) {
 	result := tk.MustQuery(`SELECT Password FROM mysql.User WHERE User="test" and Host="localhost"`)
 	result.Check(nil)
 
+	// Test for DROP ROLE.
 	createRoleSQL := `CREATE ROLE 'test'@'localhost';`
 	tk.MustExec(createRoleSQL)
 	// Make sure user test in mysql.User.
@@ -119,6 +120,27 @@ func (s *testSuite3) TestRole(c *C) {
 	result.Check(nil)
 	result = tk.MustQuery(`SELECT * FROM mysql.default_roles WHERE DEFAULT_ROLE_USER="test" and DEFAULT_ROLE_HOST="localhost"`)
 	result.Check(nil)
+
+	// Test for GRANT ROLE
+	createRoleSQL = `CREATE ROLE 'r_1'@'localhost', 'r_2'@'localhost', 'r_3'@'localhost';`
+	tk.MustExec(createRoleSQL)
+	grantRoleSQL := `GRANT 'r_1'@'localhost' TO 'r_2'@'localhost';`
+	tk.MustExec(grantRoleSQL)
+	result = tk.MustQuery(`SELECT TO_USER FROM mysql.role_edges WHERE FROM_USER="r_1" and FROM_HOST="localhost"`)
+	result.Check(testkit.Rows("r_2"))
+
+	grantRoleSQL = `GRANT 'r_1'@'localhost' TO 'r_3'@'localhost', 'r_4'@'localhost';`
+	_, err = tk.Exec(grantRoleSQL)
+	c.Check(err, NotNil)
+	result = tk.MustQuery(`SELECT FROM_USER FROM mysql.role_edges WHERE TO_USER="r_3" and TO_HOST="localhost"`)
+	result.Check(nil)
+
+	dropRoleSQL := `DROP ROLE IF EXISTS 'r_1'@'localhost' ;`
+	tk.MustExec(dropRoleSQL)
+	dropRoleSQL = `DROP ROLE IF EXISTS 'r_2'@'localhost' ;`
+	tk.MustExec(dropRoleSQL)
+	dropRoleSQL = `DROP ROLE IF EXISTS 'r_3'@'localhost' ;`
+	tk.MustExec(dropRoleSQL)
 }
 
 func (s *testSuite3) TestUser(c *C) {

planner/core/planbuilder.go

@@ -232,8 +232,9 @@ func (b *PlanBuilder) Build(node ast.Node) (Plan, error) {
 	case *ast.AnalyzeTableStmt:
 		return b.buildAnalyze(x)
 	case *ast.BinlogStmt, *ast.FlushStmt, *ast.UseStmt,
-		*ast.BeginStmt, *ast.CommitStmt, *ast.RollbackStmt, *ast.CreateUserStmt, *ast.SetPwdStmt, *ast.GrantStmt,
-		*ast.DropUserStmt, *ast.AlterUserStmt, *ast.RevokeStmt, *ast.KillStmt, *ast.DropStatsStmt, *ast.SetRoleStmt:
+		*ast.BeginStmt, *ast.CommitStmt, *ast.RollbackStmt, *ast.CreateUserStmt, *ast.SetPwdStmt,
+		*ast.GrantStmt, *ast.DropUserStmt, *ast.AlterUserStmt, *ast.RevokeStmt, *ast.KillStmt, *ast.DropStatsStmt,
+		*ast.GrantRoleStmt, *ast.SetRoleStmt:
 		return b.buildSimple(node.(ast.StmtNode))
 	case ast.DDLNode:
 		return b.buildDDL(x)
@@ -1062,6 +1063,9 @@ func (b *PlanBuilder) buildSimple(node ast.StmtNode) (Plan, error) {
 		b.visitInfo = appendVisitInfo(b.visitInfo, mysql.CreateUserPriv, "", "", "", err)
 	case *ast.GrantStmt:
 		b.visitInfo = collectVisitInfoFromGrantStmt(b.ctx, b.visitInfo, raw)
+	case *ast.GrantRoleStmt:
+		err := ErrSpecificAccessDenied.GenWithStackByArgs("GRANT ROLE")
+		b.visitInfo = appendVisitInfo(b.visitInfo, mysql.GrantPriv, "", "", "", err)
 	case *ast.RevokeStmt:
 		b.visitInfo = appendVisitInfo(b.visitInfo, mysql.SuperPriv, "", "", "", nil)
 	case *ast.KillStmt: