schedule.go

Documentation: github.com/chaos-mesh/chaos-mesh/cmd/chaos-builder

     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 main
    17  
    18  import (
    19  	"bytes"
    20  	"fmt"
    21  	"text/template"
    22  )
    23  
    24  const scheduleTemplate = `
    25  	allScheduleItem.register(Kind{{.Type}}, &ChaosKind{
    26  		chaos: &{{.Type}}{},
    27  		list:  &{{.Type}}List{},
    28  	})
    29  `
    30  
    31  func generateScheduleRegister(name string) string {
    32  	tmpl, err := template.New("ini").Parse(scheduleTemplate)
    33  	if err != nil {
    34  		log.Error(err, "fail to build template")
    35  		panic(err)
    36  	}
    37  
    38  	buf := new(bytes.Buffer)
    39  	err = tmpl.Execute(buf, &metadata{
    40  		Type: name,
    41  	})
    42  	if err != nil {
    43  		log.Error(err, "fail to execute template")
    44  		panic(err)
    45  	}
    46  
    47  	return buf.String()
    48  }
    49  
    50  type scheduleCodeGenerator struct {
    51  	// name of each Kind of chaos, for example: PodChaos, IOChaos, DNSChaos
    52  	chaosTypes []string
    53  }
    54  
    55  func newScheduleCodeGenerator(types []string) *scheduleCodeGenerator {
    56  	return &scheduleCodeGenerator{chaosTypes: types}
    57  }
    58  
    59  func (it *scheduleCodeGenerator) AppendTypes(typeName string) {
    60  	it.chaosTypes = append(it.chaosTypes, typeName)
    61  }
    62  
    63  func (it *scheduleCodeGenerator) Render() string {
    64  
    65  	scheduleTemplateTypesEntries := ""
    66  	for _, item := range it.chaosTypes {
    67  		scheduleTemplateTypesEntries += generateScheduleTemplateTypes(item)
    68  	}
    69  
    70  	embedChaosEntries := ""
    71  	for _, item := range it.chaosTypes {
    72  		embedChaosEntries += generateScheduleItem(item)
    73  	}
    74  
    75  	scheduleTemplateTypeEntries := ""
    76  	for _, item := range it.chaosTypes {
    77  		scheduleTemplateTypeEntries += fmt.Sprintf(`	ScheduleType%s,
    78  `, item)
    79  	}
    80  
    81  	spawnMethod := ""
    82  	for _, item := range it.chaosTypes {
    83  		spawnMethod += generateFillingMethodScheduleItem(item, scheduleFillingEntryTemplate)
    84  	}
    85  
    86  	restoreMethod := ""
    87  	for _, item := range it.chaosTypes {
    88  		restoreMethod += generateFillingMethodScheduleItem(item, scheduleRestoreEntryTemplate)
    89  	}
    90  
    91  	imports := `import (
    92  	"github.com/pkg/errors"
    93  )
    94  `
    95  
    96  	scheduleTemplateTypesCodes := fmt.Sprintf(`%s
    97  
    98  %s
    99  
   100  const (
   101  %s
   102  )
   103  
   104  var allScheduleTemplateType = []ScheduleTemplateType{
   105  %s
   106  }
   107  
   108  func (it *ScheduleItem) SpawnNewObject(templateType ScheduleTemplateType) (GenericChaos, error) {
   109  	switch templateType {
   110  %s
   111  	default:
   112  		return nil, errors.Wrapf(errInvalidValue, "unknown template type %%s", templateType)
   113  	}
   114  }
   115  
   116  func (it *ScheduleItem) RestoreChaosSpec(root interface{}) error {
   117  	switch chaos := root.(type) {
   118  %s
   119  	default:
   120  		return errors.Wrapf(errInvalidValue, "unknown chaos %%#v", root)
   121  	}
   122  }
   123  `,
   124  		boilerplate,
   125  		imports,
   126  		scheduleTemplateTypesEntries,
   127  		scheduleTemplateTypeEntries,
   128  		spawnMethod,
   129  		restoreMethod,
   130  	)
   131  
   132  	return scheduleTemplateTypesCodes
   133  }
   134  
   135  const scheduleTemplateTypeEntryTemplate = `	ScheduleType{{.Type}} ScheduleTemplateType = "{{.Type}}"
   136  `
   137  
   138  func generateScheduleTemplateTypes(typeName string) string {
   139  	tmpl, err := template.New("scheduleTemplates").Parse(scheduleTemplateTypeEntryTemplate)
   140  	if err != nil {
   141  		log.Error(err, "fail to build template")
   142  		return ""
   143  	}
   144  
   145  	buf := new(bytes.Buffer)
   146  	err = tmpl.Execute(buf, &metadata{
   147  		Type: typeName,
   148  	})
   149  	if err != nil {
   150  		log.Error(err, "fail to execute template")
   151  		return ""
   152  	}
   153  
   154  	return buf.String()
   155  }
   156  
   157  const scheduleItemTemplate = `	// +optional
   158  	{{.Type}} *{{.Type}}Spec ` + "`" + `json:"{{.JsonField}},omitempty"` + "`" + `
   159  `
   160  
   161  func generateScheduleItem(typeName string) string {
   162  	value := struct {
   163  		Type      string
   164  		JsonField string
   165  	}{
   166  		Type:      typeName,
   167  		JsonField: lowercaseCamelCase(typeName),
   168  	}
   169  	tmpl, err := template.New("scheduleTemplates").Parse(scheduleItemTemplate)
   170  	if err != nil {
   171  		log.Error(err, "fail to build template")
   172  		return ""
   173  	}
   174  
   175  	buf := new(bytes.Buffer)
   176  	err = tmpl.Execute(buf, &value)
   177  	if err != nil {
   178  		log.Error(err, "fail to execute template")
   179  		return ""
   180  	}
   181  
   182  	return buf.String()
   183  }
   184  
   185  const scheduleFillingEntryTemplate = `	case ScheduleType{{.Type}}:
   186  		result := {{.Type}}{}
   187  		result.Spec = *it.{{.Type}}
   188  		return &result, nil
   189  `
   190  
   191  const scheduleRestoreEntryTemplate = `	case *{{.Type}}:
   192  		*it.{{.Type}} = chaos.Spec
   193  		return nil
   194  `
   195  
   196  func generateFillingMethodScheduleItem(typeName, methodTemplate string) string {
   197  	tmpl, err := template.New("fillingMethod").Parse(methodTemplate)
   198  	if err != nil {
   199  		log.Error(err, "fail to build template")
   200  		return ""
   201  	}
   202  
   203  	buf := new(bytes.Buffer)
   204  	err = tmpl.Execute(buf, &metadata{
   205  		Type: typeName,
   206  	})
   207  	if err != nil {
   208  		log.Error(err, "fail to execute template")
   209  		return ""
   210  	}
   211  
   212  	return buf.String()
   213  }
   214