-
Notifications
You must be signed in to change notification settings - Fork 485
/
syslog.go
162 lines (136 loc) · 4.24 KB
/
syslog.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
package syslog
import (
"context"
"reflect"
"sync"
"github.com/grafana/agent/component"
"github.com/grafana/agent/component/common/loki"
flow_relabel "github.com/grafana/agent/component/common/relabel"
st "github.com/grafana/agent/component/loki/source/syslog/internal/syslogtarget"
"github.com/grafana/agent/pkg/flow/logging/level"
"github.com/prometheus/prometheus/model/relabel"
)
func init() {
component.Register(component.Registration{
Name: "loki.source.syslog",
Args: Arguments{},
Build: func(opts component.Options, args component.Arguments) (component.Component, error) {
return New(opts, args.(Arguments))
},
})
}
// Arguments holds values which are used to configure the loki.source.syslog
// component.
type Arguments struct {
SyslogListeners []ListenerConfig `river:"listener,block"`
ForwardTo []loki.LogsReceiver `river:"forward_to,attr"`
RelabelRules flow_relabel.Rules `river:"relabel_rules,attr,optional"`
}
// Component implements the loki.source.syslog component.
type Component struct {
opts component.Options
metrics *st.Metrics
mut sync.RWMutex
args Arguments
fanout []loki.LogsReceiver
targets []*st.SyslogTarget
handler loki.LogsReceiver
}
// New creates a new loki.source.syslog component.
func New(o component.Options, args Arguments) (*Component, error) {
c := &Component{
opts: o,
metrics: st.NewMetrics(o.Registerer),
handler: loki.NewLogsReceiver(),
fanout: args.ForwardTo,
targets: []*st.SyslogTarget{},
}
// Call to Update() to start readers and set receivers once at the start.
if err := c.Update(args); err != nil {
return nil, err
}
return c, nil
}
// Run implements component.Component.
func (c *Component) Run(ctx context.Context) error {
defer func() {
level.Info(c.opts.Logger).Log("msg", "loki.source.syslog component shutting down, stopping listeners")
for _, l := range c.targets {
err := l.Stop()
if err != nil {
level.Error(c.opts.Logger).Log("msg", "error while stopping syslog listener", "err", err)
}
}
}()
for {
select {
case <-ctx.Done():
return nil
case entry := <-c.handler.Chan():
c.mut.RLock()
for _, receiver := range c.fanout {
receiver.Chan() <- entry
}
c.mut.RUnlock()
}
}
}
// Update implements component.Component.
func (c *Component) Update(args component.Arguments) error {
c.mut.Lock()
defer c.mut.Unlock()
newArgs := args.(Arguments)
c.fanout = newArgs.ForwardTo
var rcs []*relabel.Config
if newArgs.RelabelRules != nil && len(newArgs.RelabelRules) > 0 {
rcs = flow_relabel.ComponentToPromRelabelConfigs(newArgs.RelabelRules)
}
if listenersChanged(c.args.SyslogListeners, newArgs.SyslogListeners) || relabelRulesChanged(c.args.RelabelRules, newArgs.RelabelRules) {
for _, l := range c.targets {
err := l.Stop()
if err != nil {
level.Error(c.opts.Logger).Log("msg", "error while stopping syslog listener", "err", err)
}
}
c.targets = make([]*st.SyslogTarget, 0)
entryHandler := loki.NewEntryHandler(c.handler.Chan(), func() {})
for _, cfg := range newArgs.SyslogListeners {
t, err := st.NewSyslogTarget(c.metrics, c.opts.Logger, entryHandler, rcs, cfg.Convert())
if err != nil {
level.Error(c.opts.Logger).Log("msg", "failed to create syslog listener with provided config", "err", err)
continue
}
c.targets = append(c.targets, t)
}
c.args = newArgs
}
return nil
}
// DebugInfo returns information about the status of listeners.
func (c *Component) DebugInfo() interface{} {
var res readerDebugInfo
for _, t := range c.targets {
res.ListenersInfo = append(res.ListenersInfo, listenerInfo{
Type: string(t.Type()),
Ready: t.Ready(),
ListenAddress: t.ListenAddress().String(),
Labels: t.Labels().String(),
})
}
return res
}
type readerDebugInfo struct {
ListenersInfo []listenerInfo `river:"listeners_info,attr"`
}
type listenerInfo struct {
Type string `river:"type,attr"`
Ready bool `river:"ready,attr"`
ListenAddress string `river:"listen_address,attr"`
Labels string `river:"labels,attr"`
}
func listenersChanged(prev, next []ListenerConfig) bool {
return !reflect.DeepEqual(prev, next)
}
func relabelRulesChanged(prev, next flow_relabel.Rules) bool {
return !reflect.DeepEqual(prev, next)
}