-
Notifications
You must be signed in to change notification settings - Fork 782
/
nomad_service.go
185 lines (153 loc) · 4.27 KB
/
nomad_service.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
// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0
package dependency
import (
"encoding/gob"
"fmt"
"log"
"net/url"
"regexp"
"sort"
"github.com/pkg/errors"
)
var (
// Ensure NomadServiceQuery meets the Dependency interface.
_ Dependency = (*NomadServiceQuery)(nil)
// NomadServiceQueryRe is the regex that is used to understand a service
// specific Nomad query.
//
// e.g. "<tag=value>.<name>@<region>"
NomadServiceQueryRe = regexp.MustCompile(`\A` + tagRe + serviceNameRe + regionRe + `\z`)
)
func init() {
gob.Register([]*NomadService{})
}
// NomadService is a fully hydrated service registration response from the
// mirroring the Nomad API response object.
type NomadService struct {
ID string
Name string
Node string
Address string
Port int
Datacenter string
Tags ServiceTags
JobID string
AllocID string
}
// NomadServiceQuery is the representation of a requested Nomad services
// dependency from inside a template.
type NomadServiceQuery struct {
stopCh chan struct{}
region string
name string
tag string
choose string
}
// NewNomadServiceQuery parses a string into a NomadServiceQuery which is
// used to list services registered within Nomad which match a particular name.
func NewNomadServiceQuery(s string) (*NomadServiceQuery, error) {
if !NomadServiceQueryRe.MatchString(s) {
return nil, fmt.Errorf("nomad.service: invalid format: %q", s)
}
m := regexpMatch(NomadServiceQueryRe, s)
return &NomadServiceQuery{
stopCh: make(chan struct{}, 1),
region: m["region"],
name: m["name"],
tag: m["tag"],
}, nil
}
// NewNomadServiceChooseQuery parses s using NewNomadServiceQuery, and then also
// configures the resulting query with the choose parameter set according to the
// count and key arguments.
func NewNomadServiceChooseQuery(count int, key, s string) (*NomadServiceQuery, error) {
query, err := NewNomadServiceQuery(s)
if err != nil {
return nil, err
}
choose := fmt.Sprintf("%d|%s", count, key)
query.choose = choose
return query, nil
}
// Fetch queries the Nomad API defined by the given client and returns a slice
// of NomadService objects.
func (d *NomadServiceQuery) Fetch(client *ClientSet, opts *QueryOptions) (interface{}, *ResponseMetadata, error) {
select {
case <-d.stopCh:
return nil, nil, ErrStopped
default:
}
opts = opts.Merge(&QueryOptions{
Region: d.region,
Choose: d.choose,
})
u := &url.URL{
Path: "/v1/service/" + d.name,
RawQuery: opts.String(),
}
log.Printf("[TRACE] %s: GET %s", d, u)
entries, qm, err := client.Nomad().Services().Get(d.name, opts.ToNomadOpts())
if err != nil {
return nil, nil, errors.Wrap(err, d.String())
}
log.Printf("[TRACE] %s: returned %d results", d, len(entries))
services := make([]*NomadService, 0, len(entries))
for _, s := range entries {
// Filter by tag
if d.tag != "" {
found := false
for i := 0; !found && i < len(s.Tags); i++ {
found = s.Tags[i] == d.tag
}
if !found {
continue
}
}
services = append(services, &NomadService{
ID: s.ID,
Name: s.ServiceName,
Node: s.NodeID,
Address: s.Address,
Port: s.Port,
Datacenter: s.Datacenter,
Tags: deepCopyAndSortTags(s.Tags),
JobID: s.JobID,
AllocID: s.AllocID,
})
}
sort.Stable(NomadServiceByName(services))
rm := &ResponseMetadata{
LastIndex: qm.LastIndex,
}
return services, rm, nil
}
func (d *NomadServiceQuery) CanShare() bool {
return true
}
func (d *NomadServiceQuery) String() string {
name := d.name
if d.tag != "" {
name = d.tag + "." + name
}
if d.region != "" {
name = name + "@" + d.region
}
if d.choose != "" {
name = name + ":" + d.choose
}
return fmt.Sprintf("nomad.service(%s)", name)
}
// Stop halts the dependency's fetch function.
func (d *NomadServiceQuery) Stop() {
close(d.stopCh)
}
// Type returns the type of this dependency.
func (d *NomadServiceQuery) Type() Type {
return TypeNomad
}
// NomadServiceByName is a sortable slice of NomadService structs.
type NomadServiceByName []*NomadService
func (s NomadServiceByName) Len() int { return len(s) }
func (s NomadServiceByName) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s NomadServiceByName) Less(i, j int) bool { return s[i].Name < s[j].Name }