selector.go

Documentation: github.com/chaos-mesh/chaos-mesh/pkg/selector

     1  // Copyright 2021 Chaos Mesh Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  // http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  //
    15  
    16  package selector
    17  
    18  import (
    19  	"context"
    20  	"reflect"
    21  
    22  	"github.com/pkg/errors"
    23  	"go.uber.org/fx"
    24  
    25  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/aws"
    26  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/azure"
    27  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/container"
    28  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/gcp"
    29  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/nodevolumepath"
    30  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/physicalmachine"
    31  	"github.com/chaos-mesh/chaos-mesh/pkg/selector/pod"
    32  )
    33  
    34  type Selector struct {
    35  	selectorMap map[reflect.Type]interface{}
    36  }
    37  
    38  type Target interface {
    39  	Id() string
    40  }
    41  
    42  func (s *Selector) Select(ctx context.Context, spec interface{}) ([]Target, error) {
    43  	if spec == nil {
    44  		return []Target{}, nil
    45  	}
    46  
    47  	var targets []Target
    48  	impl, ok := s.selectorMap[reflect.TypeOf(spec)]
    49  	if ok {
    50  		vals := reflect.ValueOf(impl).MethodByName("Select").Call([]reflect.Value{reflect.ValueOf(ctx), reflect.ValueOf(spec)})
    51  		ret := vals[0]
    52  
    53  		for i := 0; i < ret.Len(); i++ {
    54  			targets = append(targets, ret.Index(i).Interface().(Target))
    55  		}
    56  
    57  		err := vals[1].Interface()
    58  		if err == nil {
    59  			return targets, nil
    60  		}
    61  
    62  		return targets, err.(error)
    63  	}
    64  
    65  	return nil, errors.Errorf("specification type not found: %s", reflect.TypeOf(spec))
    66  }
    67  
    68  type SelectorParams struct {
    69  	fx.In
    70  
    71  	PodSelector             *pod.SelectImpl
    72  	ContainerSelector       *container.SelectImpl
    73  	AWSSelector             *aws.SelectImpl
    74  	AzureSelector           *azure.SelectImpl
    75  	GCPSelector             *gcp.SelectImpl
    76  	PhysicalMachineSelector *physicalmachine.SelectImpl
    77  	NodeVolumePath          *nodevolumepath.SelectImpl
    78  }
    79  
    80  func New(p SelectorParams) *Selector {
    81  	selectorMap := make(map[reflect.Type]interface{})
    82  
    83  	val := reflect.ValueOf(p)
    84  	for i := 0; i < val.NumField(); i++ {
    85  		method := val.Field(i).MethodByName("Select")
    86  		if method.IsValid() && method.Type().NumIn() > 1 {
    87  			typ := method.Type().In(1)
    88  			selectorMap[typ] = val.Field(i).Interface()
    89  		}
    90  	}
    91  
    92  	return &Selector{
    93  		selectorMap,
    94  	}
    95  }
    96  
    97  var Module = fx.Provide(
    98  	New,
    99  
   100  	pod.New,
   101  	container.New,
   102  	aws.New,
   103  	azure.New,
   104  	gcp.New,
   105  	physicalmachine.New,
   106  	nodevolumepath.New,
   107  )
   108