github.com/pensu/helm@v2.6.1+incompatible/pkg/resolver/resolver.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 resolver
    17  
    18  import (
    19  	"bytes"
    20  	"encoding/json"
    21  	"fmt"
    22  	"os"
    23  	"path/filepath"
    24  	"strings"
    25  	"time"
    26  
    27  	"github.com/Masterminds/semver"
    28  
    29  	"k8s.io/helm/pkg/chartutil"
    30  	"k8s.io/helm/pkg/helm/helmpath"
    31  	"k8s.io/helm/pkg/provenance"
    32  	"k8s.io/helm/pkg/repo"
    33  )
    34  
    35  // Resolver resolves dependencies from semantic version ranges to a particular version.
    36  type Resolver struct {
    37  	chartpath string
    38  	helmhome  helmpath.Home
    39  }
    40  
    41  // New creates a new resolver for a given chart and a given helm home.
    42  func New(chartpath string, helmhome helmpath.Home) *Resolver {
    43  	return &Resolver{
    44  		chartpath: chartpath,
    45  		helmhome:  helmhome,
    46  	}
    47  }
    48  
    49  // Resolve resolves dependencies and returns a lock file with the resolution.
    50  func (r *Resolver) Resolve(reqs *chartutil.Requirements, repoNames map[string]string, d string) (*chartutil.RequirementsLock, error) {
    51  
    52  	// Now we clone the dependencies, locking as we go.
    53  	locked := make([]*chartutil.Dependency, len(reqs.Dependencies))
    54  	missing := []string{}
    55  	for i, d := range reqs.Dependencies {
    56  		if strings.HasPrefix(d.Repository, "file://") {
    57  
    58  			if _, err := GetLocalPath(d.Repository, r.chartpath); err != nil {
    59  				return nil, err
    60  			}
    61  
    62  			locked[i] = &chartutil.Dependency{
    63  				Name:       d.Name,
    64  				Repository: d.Repository,
    65  				Version:    d.Version,
    66  			}
    67  			continue
    68  		}
    69  		constraint, err := semver.NewConstraint(d.Version)
    70  		if err != nil {
    71  			return nil, fmt.Errorf("dependency %q has an invalid version/constraint format: %s", d.Name, err)
    72  		}
    73  
    74  		repoIndex, err := repo.LoadIndexFile(r.helmhome.CacheIndex(repoNames[d.Name]))
    75  		if err != nil {
    76  			return nil, fmt.Errorf("no cached repo found. (try 'helm repo update'). %s", err)
    77  		}
    78  
    79  		vs, ok := repoIndex.Entries[d.Name]
    80  		if !ok {
    81  			return nil, fmt.Errorf("%s chart not found in repo %s", d.Name, d.Repository)
    82  		}
    83  
    84  		locked[i] = &chartutil.Dependency{
    85  			Name:       d.Name,
    86  			Repository: d.Repository,
    87  		}
    88  		found := false
    89  		// The version are already sorted and hence the first one to satisfy the constraint is used
    90  		for _, ver := range vs {
    91  			v, err := semver.NewVersion(ver.Version)
    92  			if err != nil || len(ver.URLs) == 0 {
    93  				// Not a legit entry.
    94  				continue
    95  			}
    96  			if constraint.Check(v) {
    97  				found = true
    98  				locked[i].Version = v.Original()
    99  				break
   100  			}
   101  		}
   102  
   103  		if !found {
   104  			missing = append(missing, d.Name)
   105  		}
   106  	}
   107  	if len(missing) > 0 {
   108  		return nil, fmt.Errorf("Can't get a valid version for repositories %s. Try changing the version constraint in requirements.yaml", strings.Join(missing, ", "))
   109  	}
   110  	return &chartutil.RequirementsLock{
   111  		Generated:    time.Now(),
   112  		Digest:       d,
   113  		Dependencies: locked,
   114  	}, nil
   115  }
   116  
   117  // HashReq generates a hash of the requirements.
   118  //
   119  // This should be used only to compare against another hash generated by this
   120  // function.
   121  func HashReq(req *chartutil.Requirements) (string, error) {
   122  	data, err := json.Marshal(req)
   123  	if err != nil {
   124  		return "", err
   125  	}
   126  	s, err := provenance.Digest(bytes.NewBuffer(data))
   127  	return "sha256:" + s, err
   128  }
   129  
   130  // GetLocalPath generates absolute local path when use
   131  // "file://" in repository of requirements
   132  func GetLocalPath(repo string, chartpath string) (string, error) {
   133  	var depPath string
   134  	var err error
   135  	p := strings.TrimPrefix(repo, "file://")
   136  
   137  	// root path is absolute
   138  	if strings.HasPrefix(p, "/") {
   139  		if depPath, err = filepath.Abs(p); err != nil {
   140  			return "", err
   141  		}
   142  	} else {
   143  		depPath = filepath.Join(chartpath, p)
   144  	}
   145  
   146  	if _, err = os.Stat(depPath); os.IsNotExist(err) {
   147  		return "", fmt.Errorf("directory %s not found", depPath)
   148  	} else if err != nil {
   149  		return "", err
   150  	}
   151  
   152  	return depPath, nil
   153  }