github.com/darkowlzz/helm@v2.5.1-0.20171213183701-6707fe0468d4+incompatible/pkg/plugin/installer/installer.go (about)

     1  /*
     2  Copyright 2016 The Kubernetes Authors All rights reserved.
     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 installer
    17  
    18  import (
    19  	"errors"
    20  	"fmt"
    21  	"os"
    22  	"path"
    23  	"path/filepath"
    24  
    25  	"k8s.io/helm/pkg/helm/helmpath"
    26  	"strings"
    27  )
    28  
    29  // ErrMissingMetadata indicates that plugin.yaml is missing.
    30  var ErrMissingMetadata = errors.New("plugin metadata (plugin.yaml) missing")
    31  
    32  // Debug enables verbose output.
    33  var Debug bool
    34  
    35  // Installer provides an interface for installing helm client plugins.
    36  type Installer interface {
    37  	// Install adds a plugin to $HELM_HOME.
    38  	Install() error
    39  	// Path is the directory of the installed plugin.
    40  	Path() string
    41  	// Update updates a plugin to $HELM_HOME.
    42  	Update() error
    43  }
    44  
    45  // Install installs a plugin to $HELM_HOME.
    46  func Install(i Installer) error {
    47  	if _, pathErr := os.Stat(path.Dir(i.Path())); os.IsNotExist(pathErr) {
    48  		return errors.New(`plugin home "$HELM_HOME/plugins" does not exist`)
    49  	}
    50  
    51  	if _, pathErr := os.Stat(i.Path()); !os.IsNotExist(pathErr) {
    52  		return errors.New("plugin already exists")
    53  	}
    54  
    55  	return i.Install()
    56  }
    57  
    58  // Update updates a plugin in $HELM_HOME.
    59  func Update(i Installer) error {
    60  	if _, pathErr := os.Stat(i.Path()); os.IsNotExist(pathErr) {
    61  		return errors.New("plugin does not exist")
    62  	}
    63  
    64  	return i.Update()
    65  }
    66  
    67  // NewForSource determines the correct Installer for the given source.
    68  func NewForSource(source, version string, home helmpath.Home) (Installer, error) {
    69  	// Check if source is a local directory
    70  	if isLocalReference(source) {
    71  		return NewLocalInstaller(source, home)
    72  	} else if isRemoteHTTPArchive(source) {
    73  		return NewHTTPInstaller(source, home)
    74  	}
    75  	return NewVCSInstaller(source, version, home)
    76  }
    77  
    78  // FindSource determines the correct Installer for the given source.
    79  func FindSource(location string, home helmpath.Home) (Installer, error) {
    80  	installer, err := existingVCSRepo(location, home)
    81  	if err != nil && err.Error() == "Cannot detect VCS" {
    82  		return installer, errors.New("cannot get information about plugin source")
    83  	}
    84  	return installer, err
    85  }
    86  
    87  // isLocalReference checks if the source exists on the filesystem.
    88  func isLocalReference(source string) bool {
    89  	_, err := os.Stat(source)
    90  	return err == nil
    91  }
    92  
    93  // isRemoteHTTPArchive checks if the source is a http/https url and is an archive
    94  func isRemoteHTTPArchive(source string) bool {
    95  	if strings.HasPrefix(source, "http://") || strings.HasPrefix(source, "https://") {
    96  		for suffix := range Extractors {
    97  			if strings.HasSuffix(source, suffix) {
    98  				return true
    99  			}
   100  		}
   101  	}
   102  	return false
   103  }
   104  
   105  // isPlugin checks if the directory contains a plugin.yaml file.
   106  func isPlugin(dirname string) bool {
   107  	_, err := os.Stat(filepath.Join(dirname, "plugin.yaml"))
   108  	return err == nil
   109  }
   110  
   111  func debug(format string, args ...interface{}) {
   112  	if Debug {
   113  		format = fmt.Sprintf("[debug] %s\n", format)
   114  		fmt.Printf(format, args...)
   115  	}
   116  }