forked from rueian/cony
/
consumer.go
159 lines (141 loc) · 2.96 KB
/
consumer.go
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package main
import (
"encoding/json"
"flag"
"fmt"
"log"
"net/smtp"
"github.com/Dcard/cony"
)
var url = flag.String("url", "amqp://guest:guest@localhost/", "amqp url")
func showUsageAndStatus() {
fmt.Printf("Consumer is running\n\n")
fmt.Println("Flags:")
flag.PrintDefaults()
fmt.Printf("\n\n")
}
// Item struct is used to send down a channel
// the map received from a delivery and the callbacks
// for acknowledge(Ack) or negatively acknowledge(Nack)
type item struct {
ipt map[string]string
ack func(bool) error
nack func(bool, bool) error
}
func main() {
flag.Parse()
showUsageAndStatus()
// Channel used for stopping goroutines
done := make(chan struct{})
// Items channel used for sending our delivieries to the workers
itms := make(chan item)
// Construct new client with the flag url
// and default backoff policy
cli := cony.NewClient(
cony.URL(*url),
cony.Backoff(cony.DefaultBackoff),
)
// Declarations
// The queue name will be supplied by the AMQP server
que := &cony.Queue{
AutoDelete: true,
}
exc := cony.Exchange{
Name: "email",
Kind: "fanout",
AutoDelete: true,
}
bnd := cony.Binding{
Queue: que,
Exchange: exc,
Key: "",
}
cli.Declare([]cony.Declaration{
cony.DeclareQueue(que),
cony.DeclareExchange(exc),
cony.DeclareBinding(bnd),
})
// Declare and register a consumer
cns := cony.NewConsumer(
que,
)
cli.Consume(cns)
// Go routing that uses the cony loop to receive delivieris
// handle reconnects, etc
// We use the done channel to exit from this goroutine.
go func() {
for cli.Loop() {
select {
case msg := <-cns.Deliveries():
var ipt map[string]string
err := json.Unmarshal(msg.Body, &ipt)
if err != nil {
msg.Reject(false)
}
log.Printf("Received body: %q\n", msg.Body)
// If when we built the consumer we didn't use
// the "cony.AutoAck()" option this is where we'd
// have to call the "amqp.Deliveries" methods "Ack",
// "Nack", "Reject"
//
// msg.Ack(false)
// msg.Nack(false)
// msg.Reject(false)
itms <- item{
ipt: ipt,
ack: msg.Ack,
nack: msg.Nack,
}
case err := <-cns.Errors():
fmt.Printf("Consumer error: %v\n", err)
case err := <-cli.Errors():
fmt.Printf("Client error: %v\n", err)
case <-done:
return
}
}
}()
// Workers
go func() {
num := 3
for i := 0; i < num; i++ {
go func() {
for {
select {
case itm := <-itms:
err := sendMail(itm.ipt)
if err != nil {
fmt.Println(err)
}
itm.ack(false)
case <-done:
return
}
}
}()
}
}()
// Block this indefinitely
<-done
}
func sendMail(ipt map[string]string) error {
// mail settings
var (
usr string = ""
pwd string = ""
hst string = "smtp.gmail.com"
prt string = "587"
)
return smtp.SendMail(
fmt.Sprintf("%v:%v", hst, prt),
smtp.PlainAuth(
"",
usr,
pwd,
hst,
),
usr,
[]string{ipt["to"]},
[]byte(ipt["message"]),
)
}