harness-drone/plugin/webhook/webhook.go
2019-02-28 16:23:06 -08:00

100 lines
2 KiB
Go

// Copyright 2019 Drone.IO Inc. All rights reserved.
// Use of this source code is governed by the Drone Non-Commercial License
// that can be found in the LICENSE file.
// +build !oss
package webhook
import (
"bytes"
"context"
"crypto/sha256"
"encoding/base64"
"encoding/json"
"net/http"
"time"
"github.com/drone/drone/core"
"github.com/99designs/httpsignatures-go"
)
// required http headers
var headers = []string{
"date",
"digest",
}
var signer = httpsignatures.NewSigner(
httpsignatures.AlgorithmHmacSha256,
headers...,
)
// New returns a new Webhook sender.
func New(endpoints []string, secret string) core.WebhookSender {
return &sender{
Endpoints: endpoints,
Secret: secret,
}
}
type sender struct {
Client *http.Client
Endpoints []string
Secret string
}
// Send sends the JSON encoded webhook to the global
// HTTP endpoints.
func (s *sender) Send(ctx context.Context, payload *core.WebhookData) error {
if len(s.Endpoints) == 0 {
return nil
}
data, _ := json.Marshal(payload)
for _, endpoint := range s.Endpoints {
err := s.send(endpoint, s.Secret, payload.Event, data)
if err != nil {
return err
}
}
return nil
}
func (s *sender) send(endpoint, secret, event string, data []byte) error {
ctx := context.Background()
ctx, cancel := context.WithTimeout(ctx, time.Minute)
defer cancel()
buf := bytes.NewBuffer(data)
req, err := http.NewRequest("POST", endpoint, buf)
if err != nil {
return err
}
req = req.WithContext(ctx)
req.Header.Add("X-Drone-Event", event)
req.Header.Add("Content-Type", "application/json")
req.Header.Add("Digest", "SHA-256="+digest(data))
req.Header.Add("Date", time.Now().UTC().Format(http.TimeFormat))
err = signer.SignRequest("hmac-key", s.Secret, req)
res, err := s.client().Do(req)
if res != nil {
res.Body.Close()
}
return err
}
func (s *sender) client() *http.Client {
if s.Client == nil {
return http.DefaultClient
}
return s.Client
}
func digest(data []byte) string {
h := sha256.New()
h.Write(data)
return base64.StdEncoding.EncodeToString(h.Sum(nil))
}