github.com/azure-devops-engineer/helm@v3.0.0-alpha.2+incompatible/pkg/lint/rules/template.go (about)

     1  /*
     2  Copyright The Helm 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 rules
    18  
    19  import (
    20  	"os"
    21  	"path/filepath"
    22  
    23  	"github.com/pkg/errors"
    24  	"sigs.k8s.io/yaml"
    25  
    26  	"helm.sh/helm/pkg/chart/loader"
    27  	"helm.sh/helm/pkg/chartutil"
    28  	"helm.sh/helm/pkg/engine"
    29  	"helm.sh/helm/pkg/lint/support"
    30  )
    31  
    32  // Templates lints the templates in the Linter.
    33  func Templates(linter *support.Linter, values map[string]interface{}, namespace string, strict bool) {
    34  	path := "templates/"
    35  	templatesPath := filepath.Join(linter.ChartDir, path)
    36  
    37  	templatesDirExist := linter.RunLinterRule(support.WarningSev, path, validateTemplatesDir(templatesPath))
    38  
    39  	// Templates directory is optional for now
    40  	if !templatesDirExist {
    41  		return
    42  	}
    43  
    44  	// Load chart and parse templates, based on tiller/release_server
    45  	chart, err := loader.Load(linter.ChartDir)
    46  
    47  	chartLoaded := linter.RunLinterRule(support.ErrorSev, path, err)
    48  
    49  	if !chartLoaded {
    50  		return
    51  	}
    52  
    53  	options := chartutil.ReleaseOptions{
    54  		Name:      "testRelease",
    55  		Namespace: namespace,
    56  	}
    57  
    58  	cvals, err := chartutil.CoalesceValues(chart, values)
    59  	if err != nil {
    60  		return
    61  	}
    62  	valuesToRender, err := chartutil.ToRenderValues(chart, cvals, options, nil)
    63  	if err != nil {
    64  		// FIXME: This seems to generate a duplicate, but I can't find where the first
    65  		// error is coming from.
    66  		//linter.RunLinterRule(support.ErrorSev, err)
    67  		return
    68  	}
    69  	var e engine.Engine
    70  	e.Strict = strict
    71  	e.LintMode = true
    72  	renderedContentMap, err := e.Render(chart, valuesToRender)
    73  
    74  	renderOk := linter.RunLinterRule(support.ErrorSev, path, err)
    75  
    76  	if !renderOk {
    77  		return
    78  	}
    79  
    80  	/* Iterate over all the templates to check:
    81  	- It is a .yaml file
    82  	- All the values in the template file is defined
    83  	- {{}} include | quote
    84  	- Generated content is a valid Yaml file
    85  	- Metadata.Namespace is not set
    86  	*/
    87  	for _, template := range chart.Templates {
    88  		fileName, _ := template.Name, template.Data
    89  		path = fileName
    90  
    91  		linter.RunLinterRule(support.ErrorSev, path, validateAllowedExtension(fileName))
    92  
    93  		// We only apply the following lint rules to yaml files
    94  		if filepath.Ext(fileName) != ".yaml" || filepath.Ext(fileName) == ".yml" {
    95  			continue
    96  		}
    97  
    98  		// NOTE: disabled for now, Refs https://github.com/helm/helm/issues/1463
    99  		// Check that all the templates have a matching value
   100  		//linter.RunLinterRule(support.WarningSev, path, validateNoMissingValues(templatesPath, valuesToRender, preExecutedTemplate))
   101  
   102  		// NOTE: disabled for now, Refs https://github.com/helm/helm/issues/1037
   103  		// linter.RunLinterRule(support.WarningSev, path, validateQuotes(string(preExecutedTemplate)))
   104  
   105  		renderedContent := renderedContentMap[filepath.Join(chart.Name(), fileName)]
   106  		var yamlStruct K8sYamlStruct
   107  		// Even though K8sYamlStruct only defines Metadata namespace, an error in any other
   108  		// key will be raised as well
   109  		err := yaml.Unmarshal([]byte(renderedContent), &yamlStruct)
   110  
   111  		validYaml := linter.RunLinterRule(support.ErrorSev, path, validateYamlContent(err))
   112  
   113  		if !validYaml {
   114  			continue
   115  		}
   116  	}
   117  }
   118  
   119  // Validation functions
   120  func validateTemplatesDir(templatesPath string) error {
   121  	if fi, err := os.Stat(templatesPath); err != nil {
   122  		return errors.New("directory not found")
   123  	} else if !fi.IsDir() {
   124  		return errors.New("not a directory")
   125  	}
   126  	return nil
   127  }
   128  
   129  func validateAllowedExtension(fileName string) error {
   130  	ext := filepath.Ext(fileName)
   131  	validExtensions := []string{".yaml", ".yml", ".tpl", ".txt"}
   132  
   133  	for _, b := range validExtensions {
   134  		if b == ext {
   135  			return nil
   136  		}
   137  	}
   138  
   139  	return errors.Errorf("file extension '%s' not valid. Valid extensions are .yaml, .yml, .tpl, or .txt", ext)
   140  }
   141  
   142  func validateYamlContent(err error) error {
   143  	return errors.Wrap(err, "unable to parse YAML")
   144  }
   145  
   146  // K8sYamlStruct stubs a Kubernetes YAML file.
   147  // Need to access for now to Namespace only
   148  type K8sYamlStruct struct {
   149  	Metadata struct {
   150  		Namespace string
   151  	}
   152  }