// Copyright 2021-2022 EMQ Technologies Co., Ltd. // // Licensed 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 xsql import ( "github.com/lf-edge/ekuiper/pkg/errorx" ) // FunctionValuer ONLY use NewFunctionValuer function to initialize type FunctionValuer struct { runtime *funcRuntime } //Should only be called by stream to make sure a single instance for an operation func NewFunctionValuer(p *funcRuntime) *FunctionValuer { fv := &FunctionValuer{ runtime: p, } return fv } func (*FunctionValuer) Value(_, _ string) (interface{}, bool) { return nil, false } func (*FunctionValuer) Meta(_, _ string) (interface{}, bool) { return nil, false } func (*FunctionValuer) AppendAlias(string, interface{}) bool { return false } func (*FunctionValuer) AliasValue(string) (interface{}, bool) { return nil, false } func (fv *FunctionValuer) Call(name string, funcId int, args []interface{}) (interface{}, bool) { nf, fctx, err := fv.runtime.Get(name, funcId) switch err { case errorx.NotFoundErr: return nil, false case nil: // do nothing, continue default: return err, false } return ExecFunc(name, nf, args, fctx) }