forked from kubernetes-retired/heapster
-
Notifications
You must be signed in to change notification settings - Fork 1
/
unit.go
257 lines (216 loc) · 7 KB
/
unit.go
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
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
// Copyright 2014 CoreOS, Inc.
//
// 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 unit
import (
"bytes"
"crypto/sha1"
"encoding/hex"
"fmt"
"io/ioutil"
"strings"
"github.com/coreos/go-systemd/unit"
)
func NewUnitFile(raw string) (*UnitFile, error) {
reader := strings.NewReader(raw)
opts, err := unit.Deserialize(reader)
if err != nil {
return nil, err
}
return NewUnitFromOptions(opts), nil
}
func NewUnitFromOptions(opts []*unit.UnitOption) *UnitFile {
return &UnitFile{mapOptions(opts), opts}
}
func mapOptions(opts []*unit.UnitOption) map[string]map[string][]string {
contents := make(map[string]map[string][]string)
for _, opt := range opts {
if _, ok := contents[opt.Section]; !ok {
contents[opt.Section] = make(map[string][]string)
}
if _, ok := contents[opt.Section][opt.Name]; !ok {
contents[opt.Section][opt.Name] = make([]string, 0)
}
var vals []string
if opt.Section == "X-Fleet" {
// The go-systemd parser does not know that our X-Fleet options support
// multivalue options, so we have to manually parse them here
vals = parseMultivalueLine(opt.Value)
} else {
vals = []string{opt.Value}
}
contents[opt.Section][opt.Name] = append(contents[opt.Section][opt.Name], vals...)
}
return contents
}
// parseMultivalueLine parses a line that includes several quoted values separated by whitespaces.
// Example: MachineMetadata="foo=bar" "baz=qux"
// If the provided line is not a multivalue string, the line is returned as the sole value.
func parseMultivalueLine(line string) (values []string) {
if !strings.HasPrefix(line, `"`) || !strings.HasSuffix(line, `"`) {
return []string{line}
}
var v bytes.Buffer
w := false // check whether we're within quotes or not
for _, e := range []byte(line) {
// ignore quotes
if e == '"' {
w = !w
continue
}
if e == ' ' {
if !w { // between quoted values, keep the previous value and reset.
values = append(values, v.String())
v.Reset()
continue
}
}
v.WriteByte(e)
}
values = append(values, v.String())
return
}
// A UnitFile represents a systemd configuration which encodes information about any of the unit
// types that fleet supports (as defined in SupportedUnitTypes()).
// UnitFiles are linked to Units by the Hash of their contents.
// Similar to systemd, a UnitFile configuration has no inherent name, but is rather
// named through the reference to it; in the case of systemd, the reference is
// the filename, and in the case of fleet, the reference is the name of the Unit
// that references this UnitFile.
type UnitFile struct {
// Contents represents the parsed unit file.
// This field must be considered readonly.
Contents map[string]map[string][]string
Options []*unit.UnitOption
}
// Description returns the first Description option found in the [Unit] section.
// If the option is not defined, an empty string is returned.
func (u *UnitFile) Description() string {
if values := u.Contents["Unit"]["Description"]; len(values) > 0 {
return values[0]
}
return ""
}
func (u *UnitFile) Bytes() []byte {
b, _ := ioutil.ReadAll(unit.Serialize(u.Options))
return b
}
func (u *UnitFile) String() string {
return string(u.Bytes())
}
// Hash returns the SHA1 hash of the raw contents of the Unit
func (u *UnitFile) Hash() Hash {
return Hash(sha1.Sum(u.Bytes()))
}
// RecognizedUnitType determines whether or not the given unit name represents
// a recognized unit type.
func RecognizedUnitType(name string) bool {
types := []string{"service", "socket", "timer", "path", "device", "mount", "automount"}
for _, t := range types {
suffix := fmt.Sprintf(".%s", t)
if strings.HasSuffix(name, suffix) {
return true
}
}
return false
}
// DefaultUnitType appends the default unit type to a given unit name, ignoring
// any file extensions that already exist.
func DefaultUnitType(name string) string {
return fmt.Sprintf("%s.service", name)
}
// SHA1 sum
type Hash [sha1.Size]byte
func (h Hash) String() string {
return fmt.Sprintf("%x", h[:])
}
func (h Hash) Short() string {
return fmt.Sprintf("%.7s", h)
}
func (h *Hash) Empty() bool {
return *h == Hash{}
}
func HashFromHexString(key string) (Hash, error) {
h := Hash{}
out, err := hex.DecodeString(key)
if err != nil {
return h, err
}
if len(out) != sha1.Size {
return h, fmt.Errorf("size of key %q (%d) differs from SHA1 size (%d)", out, len(out), sha1.Size)
}
copy(h[:], out[:sha1.Size])
return h, nil
}
// UnitState encodes the current state of a unit loaded into a fleet agent
type UnitState struct {
LoadState string
ActiveState string
SubState string
MachineID string
UnitHash string
UnitName string
}
func NewUnitState(loadState, activeState, subState, mID string) *UnitState {
return &UnitState{
LoadState: loadState,
ActiveState: activeState,
SubState: subState,
MachineID: mID,
}
}
// UnitNameInfo exposes certain interesting items about a Unit based on its
// name. For example, a unit with the name "foo@.service" constitutes a
// template unit, and a unit named "foo@1.service" would represent an instance
// unit of that template.
type UnitNameInfo struct {
FullName string // Original complete name of the unit (e.g. foo.socket, foo@bar.service)
Name string // Name of the unit without suffix (e.g. foo, foo@bar)
Prefix string // Prefix of the template unit (e.g. foo)
// If the unit represents an instance or a template, the following values are set
Template string // Name of the canonical template unit (e.g. foo@.service)
Instance string // Instance name (e.g. bar)
}
// IsInstance returns a boolean indicating whether the UnitNameInfo appears to be
// an Instance of a Template unit
func (nu UnitNameInfo) IsInstance() bool {
return len(nu.Instance) > 0
}
// IsTemplate returns a boolean indicating whether the UnitNameInfo appears to be
// a Template unit
func (nu UnitNameInfo) IsTemplate() bool {
return len(nu.Template) > 0 && !nu.IsInstance()
}
// NewUnitNameInfo generates a UnitNameInfo from the given name. If the given string
// is not a correct unit name, nil is returned.
func NewUnitNameInfo(un string) *UnitNameInfo {
// Everything past the first @ and before the last . is the instance
s := strings.LastIndex(un, ".")
if s == -1 {
return nil
}
nu := &UnitNameInfo{FullName: un}
name := un[:s]
suffix := un[s:]
nu.Name = name
a := strings.Index(name, "@")
if a == -1 {
// This does not appear to be a template or instance unit.
nu.Prefix = name
return nu
}
nu.Prefix = name[:a]
nu.Template = fmt.Sprintf("%s@%s", name[:a], suffix)
nu.Instance = name[a+1:]
return nu
}