github.com/umeshredd/helm@v3.0.0-alpha.1+incompatible/pkg/chartutil/chartfile.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 chartutil
    18  
    19  import (
    20  	"io/ioutil"
    21  	"os"
    22  	"path/filepath"
    23  	"strings"
    24  
    25  	"github.com/ghodss/yaml"
    26  	"github.com/pkg/errors"
    27  
    28  	"helm.sh/helm/pkg/chart"
    29  )
    30  
    31  // LoadChartfile loads a Chart.yaml file into a *chart.Metadata.
    32  func LoadChartfile(filename string) (*chart.Metadata, error) {
    33  	b, err := ioutil.ReadFile(filename)
    34  	if err != nil {
    35  		return nil, err
    36  	}
    37  	y := new(chart.Metadata)
    38  	err = yaml.Unmarshal(b, y)
    39  	return y, err
    40  }
    41  
    42  // SaveChartfile saves the given metadata as a Chart.yaml file at the given path.
    43  //
    44  // 'filename' should be the complete path and filename ('foo/Chart.yaml')
    45  func SaveChartfile(filename string, cf *chart.Metadata) error {
    46  	out, err := yaml.Marshal(cf)
    47  	if err != nil {
    48  		return err
    49  	}
    50  	return ioutil.WriteFile(filename, out, 0644)
    51  }
    52  
    53  // IsChartDir validate a chart directory.
    54  //
    55  // Checks for a valid Chart.yaml.
    56  func IsChartDir(dirName string) (bool, error) {
    57  	if fi, err := os.Stat(dirName); err != nil {
    58  		return false, err
    59  	} else if !fi.IsDir() {
    60  		return false, errors.Errorf("%q is not a directory", dirName)
    61  	}
    62  
    63  	chartYaml := filepath.Join(dirName, "Chart.yaml")
    64  	if _, err := os.Stat(chartYaml); os.IsNotExist(err) {
    65  		return false, errors.Errorf("no Chart.yaml exists in directory %q", dirName)
    66  	}
    67  
    68  	chartYamlContent, err := ioutil.ReadFile(chartYaml)
    69  	if err != nil {
    70  		return false, errors.Errorf("cannot read Chart.Yaml in directory %q", dirName)
    71  	}
    72  
    73  	chartContent := new(chart.Metadata)
    74  	if err := yaml.Unmarshal(chartYamlContent, &chartContent); err != nil {
    75  		return false, err
    76  	}
    77  	if chartContent == nil {
    78  		return false, errors.New("chart metadata (Chart.yaml) missing")
    79  	}
    80  	if chartContent.Name == "" {
    81  		return false, errors.New("invalid chart (Chart.yaml): name must not be empty")
    82  	}
    83  
    84  	return true, nil
    85  }
    86  
    87  // IsChartInstallable validates if a chart can be installed
    88  //
    89  // Application chart type is only installable
    90  func IsChartInstallable(chart *chart.Chart) (bool, error) {
    91  	if IsLibraryChart(chart) {
    92  		return false, errors.New("Library charts are not installable")
    93  	}
    94  	validChartType, _ := IsValidChartType(chart)
    95  	if !validChartType {
    96  		return false, errors.New("Invalid chart types are not installable")
    97  	}
    98  	return true, nil
    99  }
   100  
   101  // IsValidChartType validates the chart type
   102  //
   103  // Valid types are: application or library
   104  func IsValidChartType(chart *chart.Chart) (bool, error) {
   105  	chartType := chart.Metadata.Type
   106  	if chartType != "" && !strings.EqualFold(chartType, "library") &&
   107  		!strings.EqualFold(chartType, "application") {
   108  		return false, errors.New("Invalid chart type. Valid types are: application or library")
   109  	}
   110  	return true, nil
   111  }
   112  
   113  // IsLibraryChart returns true if the chart is a library chart
   114  func IsLibraryChart(c *chart.Chart) bool {
   115  	return strings.EqualFold(c.Metadata.Type, "library")
   116  }
   117  
   118  // IsTemplateValid returns true if the template is valid for the chart type
   119  func IsTemplateValid(templateName string, isLibChart bool) bool {
   120  	if isLibChart {
   121  		return strings.HasPrefix(filepath.Base(templateName), "_")
   122  	}
   123  	return true
   124  }