summaryrefslogtreecommitdiffstats
path: root/src/k8splugin/internal/helm/helm.go
blob: 849674a9c8be79ed985533bed271f9f10a0516b0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
/*
 * Copyright 2018 Intel Corporation, Inc
 * Copyright © 2021 Samsung Electronics
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package helm

import (
	"fmt"
	"github.com/onap/multicloud-k8s/src/k8splugin/internal/utils"
	"io/ioutil"
	"os"
	"path/filepath"
	"regexp"
	"strings"

	pkgerrors "github.com/pkg/errors"
	"helm.sh/helm/v3/pkg/action"
	"helm.sh/helm/v3/pkg/chart/loader"
	"helm.sh/helm/v3/pkg/cli"
	helmOptions "helm.sh/helm/v3/pkg/cli/values"
	"helm.sh/helm/v3/pkg/getter"
	"helm.sh/helm/v3/pkg/releaseutil"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/apimachinery/pkg/runtime/serializer/json"
	"k8s.io/apimachinery/pkg/util/validation"
	k8syaml "k8s.io/apimachinery/pkg/util/yaml"
)

// Template is the interface for all helm templating commands
// Any backend implementation will implement this interface and will
// access the functionality via this.
// FIXME Template is not referenced anywhere
type Template interface {
	GenerateKubernetesArtifacts(
		chartPath string,
		valueFiles []string,
		values []string) ([]KubernetesResourceTemplate, []*Hook, error)
}

// TemplateClient implements the Template interface
// It will also be used to maintain any localized state
type TemplateClient struct {
	emptyRegex    *regexp.Regexp
	kubeVersion   string
	kubeNameSpace string
	releaseName   string
}

// NewTemplateClient returns a new instance of TemplateClient
func NewTemplateClient(k8sversion, namespace, releasename string) *TemplateClient {
	return &TemplateClient{
		// emptyRegex defines template content that could be considered empty yaml-wise
		emptyRegex: regexp.MustCompile(`(?m)\A(^(\s*#.*|\s*)$\n?)*\z`),
		// defaultKubeVersion is the default value of --kube-version flag
		kubeVersion:   k8sversion,
		kubeNameSpace: namespace,
		releaseName:   releasename,
	}
}

// Combines valueFiles and values into a single values stream.
// values takes precedence over valueFiles
func (h *TemplateClient) processValues(valueFiles []string, values []string) (map[string]interface{}, error) {
	settings := cli.New()
	providers := getter.All(settings)
	options := helmOptions.Options{
		ValueFiles: valueFiles,
		Values:     values,
	}
	base, err := options.MergeValues(providers)
	if err != nil {
		return nil, err
	}

	return base, nil
}

// GenerateKubernetesArtifacts a mapping of type to fully evaluated helm template
func (h *TemplateClient) GenerateKubernetesArtifacts(inputPath string, valueFiles []string,
	values []string) ([]KubernetesResourceTemplate, []*Hook, error) {

	var outputDir, chartPath, namespace, releaseName string
	var retData []KubernetesResourceTemplate
	var hookList []*Hook

	releaseName = h.releaseName
	namespace = h.kubeNameSpace

	// verify chart path exists
	if _, err := os.Stat(inputPath); err == nil {
		if chartPath, err = filepath.Abs(inputPath); err != nil {
			return retData, hookList, err
		}
	} else {
		return retData, hookList, err
	}

	//Create a temp directory in the system temp folder
	outputDir, err := ioutil.TempDir("", "helm-tmpl-")
	if err != nil {
		return retData, hookList, pkgerrors.Wrap(err, "Got error creating temp dir")
	}

	if namespace == "" {
		namespace = "default"
	}

	// get combined values and create config
	rawVals, err := h.processValues(valueFiles, values)
	if err != nil {
		return retData, hookList, err
	}

	if msgs := validation.IsDNS1123Label(releaseName); releaseName != "" && len(msgs) > 0 {
		return retData, hookList, fmt.Errorf("release name %s is not a valid DNS label: %s", releaseName, strings.Join(msgs, ";"))
	}

	// Initialize the install client
	client := action.NewInstall(&action.Configuration{})
	client.DryRun = true
	client.ClientOnly = true
	client.ReleaseName = releaseName
	client.IncludeCRDs = true
	client.DisableHooks = true //to ensure no duplicates in case of defined pre/post install hooks

	// Check chart dependencies to make sure all are present in /charts
	chartRequested, err := loader.Load(chartPath)
	if err != nil {
		return retData, hookList, err
	}

	if chartRequested.Metadata.Type != "" && chartRequested.Metadata.Type != "application" {
		return retData, hookList, fmt.Errorf(
			"chart %q has an unsupported type and is not installable: %q",
			chartRequested.Metadata.Name,
			chartRequested.Metadata.Type,
		)
	}

	client.Namespace = namespace
	release, err := client.Run(chartRequested, rawVals)
	if err != nil {
		return retData, hookList, err
	}
	// SplitManifests returns integer-sortable so that manifests get output
	// in the same order as the input by `BySplitManifestsOrder`.
	rmap := releaseutil.SplitManifests(release.Manifest)
	// We won't get any meaningful hooks from here
	_, m, err := releaseutil.SortManifests(rmap, nil, releaseutil.InstallOrder)
	if err != nil {
		return retData, hookList, err
	}
	for _, k := range m {
		data := k.Content
		b := filepath.Base(k.Name)
		if b == "NOTES.txt" {
			continue
		}
		if strings.HasPrefix(b, "_") {
			continue
		}
		// blank template after execution
		if h.emptyRegex.MatchString(data) {
			continue
		}
		mfilePath := filepath.Join(outputDir, k.Name)
		utils.EnsureDirectory(mfilePath)
		err = ioutil.WriteFile(mfilePath, []byte(k.Content), 0600)
		if err != nil {
			return retData, hookList, err
		}
		gvk, err := getGroupVersionKind(data)
		if err != nil {
			return retData, hookList, err
		}
		kres := KubernetesResourceTemplate{
			GVK:      gvk,
			FilePath: mfilePath,
		}
		retData = append(retData, kres)
	}
	for _, h := range release.Hooks {
		hFilePath := filepath.Join(outputDir, h.Name)
		utils.EnsureDirectory(hFilePath)
		err = ioutil.WriteFile(hFilePath, []byte(h.Manifest), 0600)
		if err != nil {
			return retData, hookList, err
		}
		gvk, err := getGroupVersionKind(h.Manifest)
		if err != nil {
			return retData, hookList, err
		}
		hookList = append(hookList, &Hook{*h, KubernetesResourceTemplate{gvk, hFilePath}})
	}
	return retData, hookList, nil
}

func getGroupVersionKind(data string) (schema.GroupVersionKind, error) {
	out, err := k8syaml.ToJSON([]byte(data))
	if err != nil {
		return schema.GroupVersionKind{}, pkgerrors.Wrap(err, "Converting yaml to json:\n"+data)
	}

	simpleMeta := json.SimpleMetaFactory{}
	gvk, err := simpleMeta.Interpret(out)
	if err != nil {
		return schema.GroupVersionKind{}, pkgerrors.Wrap(err, "Parsing apiversion and kind")
	}

	return *gvk, nil
}