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
|
package cgi
import (
"context"
"fmt"
"io/ioutil"
"net"
"net/http"
"net/http/cgi"
"os"
"sync"
"time"
"git.capotej.com/capotej/communique/config"
"git.capotej.com/capotej/communique/models"
"github.com/mmcdole/gofeed"
"go.uber.org/zap"
)
type Servers struct {
log *zap.SugaredLogger
persister *models.Persister
}
func NewServers(log *zap.SugaredLogger, persister *models.Persister) *Servers {
return &Servers{log: log, persister: persister}
}
// Start iterates over all Handlers and starts an internal CGI server for each one
// along with ticker for the configured handler interval then blocks indefinitely
func (s *Servers) Start(cfg config.Config) {
var wg sync.WaitGroup
logger := s.log.With("type", "cgi")
for _, handler := range cfg.Handlers {
handlerLogger := logger.With("handler", handler.Name)
wg.Add(3)
// Internal CGI server
go func(aHandler config.Handler) {
defer wg.Done()
startCGIServer(aHandler, handlerLogger)
}(handler)
// Ticker
go func(aHandler config.Handler) {
defer wg.Done()
startTicker(aHandler, s.persister, handlerLogger)
}(handler)
// Execute a handler tick on start since Go's ticker waits until $interval to trigger first tick
go func(aHandler config.Handler) {
defer wg.Done()
time.Sleep(1 * time.Second)
output := tick(aHandler, handlerLogger)
err := processTick(aHandler, output, s.persister, handlerLogger)
if err != nil {
s.log.Error(err)
}
}(handler)
}
wg.Wait()
}
func startCGIServer(h config.Handler, log *zap.SugaredLogger) {
cgiHandler := cgi.Handler{Path: h.Exec}
server := http.Server{
Handler: &cgiHandler,
}
sock := fmt.Sprintf("%s.sock", h.Name)
log.Debugf("starting cgi server at %s", sock)
os.Remove(sock)
unixListener, err := net.Listen("unix", sock)
if err != nil {
panic(err)
}
server.Serve(unixListener)
}
func startTicker(h config.Handler, persister *models.Persister, log *zap.SugaredLogger) {
ticker := time.NewTicker(h.Interval) // TODO add some random jitter here so handlers dont run at the same exact intervals
done := make(chan bool)
func() {
for {
select {
case <-done:
return
case _ = <-ticker.C:
output := tick(h, log)
err := processTick(h, output, persister, log)
if err != nil {
log.Error(err)
}
}
}
}()
}
func processTick(h config.Handler, output []byte, persister *models.Persister, log *zap.SugaredLogger) error {
fp := gofeed.NewParser()
fp.ParseString(string(output))
feed, err := fp.ParseString(string(output))
if err != nil {
return err
}
for _, v := range feed.Items {
var extractedContent string
// if there is no content, use descrption
if len(v.Content) != 0 {
extractedContent = v.Content
} else if len(v.Description) != 0 {
extractedContent = v.Description
}
if len(extractedContent) != 0 {
log.Debugf("extracted content '%s'", extractedContent)
outboxItem := models.CreateOutboxItem(h, []byte(extractedContent))
err = persister.Store(outboxItem)
if err != nil {
return err
}
}
}
return nil
}
func tick(h config.Handler, log *zap.SugaredLogger) []byte {
sock := fmt.Sprintf("%s.sock", h.Name)
httpc := http.Client{
Transport: &http.Transport{
DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
return net.Dial("unix", sock)
},
},
}
var response *http.Response
var err error
log.Debugf("executing cgi handler at %s", sock)
response, err = httpc.Get("http://unix/" + sock)
if err != nil {
log.Errorf("received error from cgi handler %s", err)
}
body, err := ioutil.ReadAll(response.Body)
response.Body.Close()
return body
}
|