Fcm-go is a wrapper library of the original firebase-admin-go library. This library is a modified library that supports calling hook before and after each action. It also supports the option to inject context for the monitoring purposes.
To show the documentation of the package, we can check the code directly or by running this command:
make docThis will open the package documentation in local. We can access it in http://localhost:6060/pkg/gitlab.com/flip-id/default/fcm-go/?m=all.
This library can be used based on the example shown in the URL below:
http://localhost:6060/pkg/gitlab.com/flip-id/default/fcm-go/?m=all#New
Script:
package main
import (
"context"
"log"
"time"
"firebase.google.com/go/v4/messaging"
"google.golang.org/api/option"
"gopkg.in/DataDog/dd-trace-go.v1/ddtrace"
"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/ext"
"gopkg.in/DataDog/dd-trace-go.v1/ddtrace/tracer"
)
type contextKey string
func main() {
ctx := context.Background()
fnBefore := func(s *Session) {
dummyData := map[string][]string{
"test": {"test-header-1"},
}
var span ddtrace.Span
span, s.Ctx = tracer.StartSpanFromContext(
s.Ctx,
"http.out",
tracer.SpanType(ext.SpanTypeHTTP),
tracer.ServiceName("fcm-go"),
tracer.Measured(),
tracer.ResourceName("send"),
)
s.Ctx = context.WithValue(s.Ctx, contextKey("begin_time"), time.Now())
if err := tracer.Inject(span.Context(), tracer.HTTPHeadersCarrier(dummyData)); err != nil {
log.Printf("Error injecting span context to fcm-go client! Error: %v", err)
}
}
fnAfter := func(s *Session) {
span, _ := tracer.SpanFromContext(s.Ctx)
defer func() {
span.Finish(tracer.WithError(s.Error))
}()
begin := s.Ctx.Value(contextKey("begin_time")).(time.Time)
log.Println(
"span_id", span.Context().SpanID(),
"trace_id", span.Context().TraceID(),
"type", "send",
"duration", time.Since(begin),
"message_id", s.MessageID,
)
if s.Error != nil {
log.Printf("Fcm-go client gets error: %v", s.Error)
}
}
fcmClient, err := New(ctx,
WithAfterHook(fnAfter),
WithBeforeHook(fnBefore),
WithClientOptions(
option.WithCredentialsFile("test/data/service_account.json"),
),
)
if err != nil {
log.Fatalf("Error in getting the new client: %v", err)
}
msgID, err := fcmClient.Send(ctx, &messaging.Message{})
if err != nil {
log.Fatalf("Error in sending the message: %v", err)
}
log.Printf("The message ID: %s", msgID)
}