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
|
// Package hooks implements hook configuration and handling for CRI-O and libpod.
package hooks
import (
"context"
"fmt"
"os"
"sort"
"strings"
"sync"
current "github.com/containers/libpod/pkg/hooks/1.0.0"
rspec "github.com/opencontainers/runtime-spec/specs-go"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
)
// Version is the current hook configuration version.
const Version = current.Version
const (
// DefaultDir is the default directory containing system hook configuration files.
DefaultDir = "/usr/share/containers/oci/hooks.d"
// OverrideDir is the directory for hook configuration files overriding the default entries.
OverrideDir = "/etc/containers/oci/hooks.d"
)
// Manager provides an opaque interface for managing CRI-O hooks.
type Manager struct {
hooks map[string]*current.Hook
directories []string
extensionStages []string
lock sync.Mutex
}
type namedHook struct {
name string
hook *current.Hook
}
// New creates a new hook manager. Directories are ordered by
// increasing preference (hook configurations in later directories
// override configurations with the same filename from earlier
// directories).
//
// extensionStages allows callers to add additional stages beyond
// those specified in the OCI Runtime Specification and to control
// OCI-defined stages instead of delagating to the OCI runtime. See
// Hooks() for more information.
func New(ctx context.Context, directories []string, extensionStages []string) (manager *Manager, err error) {
manager = &Manager{
hooks: map[string]*current.Hook{},
directories: directories,
extensionStages: extensionStages,
}
for _, dir := range directories {
err = ReadDir(dir, manager.extensionStages, manager.hooks)
if err != nil && !os.IsNotExist(err) {
return nil, err
}
}
return manager, nil
}
// filenames returns sorted hook entries.
func (m *Manager) namedHooks() (hooks []*namedHook) {
m.lock.Lock()
defer m.lock.Unlock()
hooks = make([]*namedHook, len(m.hooks))
i := 0
for name, hook := range m.hooks {
hooks[i] = &namedHook{
name: name,
hook: hook,
}
i++
}
return hooks
}
// Hooks injects OCI runtime hooks for a given container configuration.
//
// If extensionStages was set when initializing the Manager,
// matching hooks requesting those stages will be returned in
// extensionStageHooks. This takes precedence over their inclusion in
// the OCI configuration. For example:
//
// manager, err := New(ctx, []string{DefaultDir}, []string{"poststop"})
// extensionStageHooks, err := manager.Hooks(config, annotations, hasBindMounts)
//
// will have any matching post-stop hooks in extensionStageHooks and
// will not insert them into config.Hooks.Poststop.
func (m *Manager) Hooks(config *rspec.Spec, annotations map[string]string, hasBindMounts bool) (extensionStageHooks map[string][]rspec.Hook, err error) {
hooks := m.namedHooks()
sort.Slice(hooks, func(i, j int) bool { return strings.ToLower(hooks[i].name) < strings.ToLower(hooks[j].name) })
localStages := map[string]bool{} // stages destined for extensionStageHooks
for _, stage := range m.extensionStages {
localStages[stage] = true
}
for _, namedHook := range hooks {
match, err := namedHook.hook.When.Match(config, annotations, hasBindMounts)
if err != nil {
return extensionStageHooks, errors.Wrapf(err, "matching hook %q", namedHook.name)
}
if match {
logrus.Debugf("hook %s matched; adding to stages %v", namedHook.name, namedHook.hook.Stages)
if config.Hooks == nil {
config.Hooks = &rspec.Hooks{}
}
for _, stage := range namedHook.hook.Stages {
if _, ok := localStages[stage]; ok {
if extensionStageHooks == nil {
extensionStageHooks = map[string][]rspec.Hook{}
}
extensionStageHooks[stage] = append(extensionStageHooks[stage], namedHook.hook.Hook)
} else {
switch stage {
case "prestart":
config.Hooks.Prestart = append(config.Hooks.Prestart, namedHook.hook.Hook)
case "poststart":
config.Hooks.Poststart = append(config.Hooks.Poststart, namedHook.hook.Hook)
case "poststop":
config.Hooks.Poststop = append(config.Hooks.Poststop, namedHook.hook.Hook)
default:
return extensionStageHooks, fmt.Errorf("hook %q: unknown stage %q", namedHook.name, stage)
}
}
}
} else {
logrus.Debugf("hook %s did not match", namedHook.name)
}
}
return extensionStageHooks, nil
}
|
