k8s.io/apiserver@v0.31.1/pkg/cel/library/test.go (about)

     1  /*
     2  Copyright 2023 The Kubernetes Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package library
    18  
    19  import (
    20  	"math"
    21  
    22  	"github.com/google/cel-go/cel"
    23  	"github.com/google/cel-go/common/types"
    24  	"github.com/google/cel-go/common/types/ref"
    25  )
    26  
    27  // Test provides a test() function that returns true.
    28  func Test(options ...TestOption) cel.EnvOption {
    29  	t := &testLib{version: math.MaxUint32}
    30  	for _, o := range options {
    31  		t = o(t)
    32  	}
    33  	return cel.Lib(t)
    34  }
    35  
    36  type testLib struct {
    37  	version uint32
    38  }
    39  
    40  func (*testLib) LibraryName() string {
    41  	return "k8s.test"
    42  }
    43  
    44  type TestOption func(*testLib) *testLib
    45  
    46  func TestVersion(version uint32) func(lib *testLib) *testLib {
    47  	return func(sl *testLib) *testLib {
    48  		sl.version = version
    49  		return sl
    50  	}
    51  }
    52  
    53  func (t *testLib) CompileOptions() []cel.EnvOption {
    54  	var options []cel.EnvOption
    55  
    56  	if t.version == 0 {
    57  		options = append(options, cel.Function("test",
    58  			cel.Overload("test", []*cel.Type{}, cel.BoolType,
    59  				cel.FunctionBinding(func(args ...ref.Val) ref.Val {
    60  					return types.True
    61  				}))))
    62  	}
    63  
    64  	if t.version >= 1 {
    65  		options = append(options, cel.Function("test",
    66  			cel.Overload("test", []*cel.Type{}, cel.BoolType,
    67  				cel.FunctionBinding(func(args ...ref.Val) ref.Val {
    68  					// Return false here so tests can observe which version of the function is registered
    69  					// Actual function libraries must not break backward compatibility
    70  					return types.False
    71  				}))))
    72  		options = append(options, cel.Function("testV1",
    73  			cel.Overload("testV1", []*cel.Type{}, cel.BoolType,
    74  				cel.FunctionBinding(func(args ...ref.Val) ref.Val {
    75  					return types.True
    76  				}))))
    77  	}
    78  	return options
    79  }
    80  
    81  func (*testLib) ProgramOptions() []cel.ProgramOption {
    82  	return []cel.ProgramOption{}
    83  }