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mirror of https://github.com/go-gitea/gitea.git synced 2024-12-04 14:46:57 -05:00
gitea/services/webhook/deliver.go
oliverpool 26653b196b
Store webhook event in database ()
Refactor the webhook logic, to have the type-dependent processing happen
only in one place.

---

## Current webhook flow

1. An event happens
2. It is pre-processed (depending on the webhook type) and its body is
added to a task queue
3. When the task is processed, some more logic (depending on the webhook
type as well) is applied to make an HTTP request

This means that webhook-type dependant logic is needed in step 2 and 3.
This is cumbersome and brittle to maintain.

Updated webhook flow with this PR:
1. An event happens
2. It is stored as-is and added to a task queue
3. When the task is processed, the event is processed (depending on the
webhook type) to make an HTTP request

So the only webhook-type dependent logic happens in one place (step 3)
which should be much more robust.

## Consequences of the refactor

- the raw event must be stored in the hooktask (until now, the
pre-processed body was stored)
- to ensure that previous hooktasks are correctly sent, a
`payload_version` is added (version 1: the body has already been
pre-process / version 2: the body is the raw event)

So future webhook additions will only have to deal with creating an
http.Request based on the raw event (no need to adjust the code in
multiple places, like currently).

Moreover since this processing happens when fetching from the task
queue, it ensures that the queuing of new events (upon a `git push` for
instance) does not get slowed down by a slow webhook.

As a concrete example, the PR  for custom webhooks, should be
substantially smaller:
- no need to change `services/webhook/deliver.go` 
- minimal change in `services/webhook/webhook.go` (add the new webhook
to the map)
- no need to change all the individual webhook files (since with this
refactor the `*webhook_model.Webhook` is provided as argument)
2024-03-07 23:18:38 +01:00

350 lines
10 KiB
Go

// Copyright 2019 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package webhook
import (
"context"
"crypto/hmac"
"crypto/sha1"
"crypto/sha256"
"crypto/tls"
"encoding/hex"
"fmt"
"io"
"net/http"
"net/url"
"strings"
"sync"
"time"
webhook_model "code.gitea.io/gitea/models/webhook"
"code.gitea.io/gitea/modules/graceful"
"code.gitea.io/gitea/modules/hostmatcher"
"code.gitea.io/gitea/modules/log"
"code.gitea.io/gitea/modules/process"
"code.gitea.io/gitea/modules/proxy"
"code.gitea.io/gitea/modules/queue"
"code.gitea.io/gitea/modules/setting"
"code.gitea.io/gitea/modules/timeutil"
webhook_module "code.gitea.io/gitea/modules/webhook"
"github.com/gobwas/glob"
)
func newDefaultRequest(ctx context.Context, w *webhook_model.Webhook, t *webhook_model.HookTask) (req *http.Request, body []byte, err error) {
switch w.HTTPMethod {
case "":
log.Info("HTTP Method for %s webhook %s [ID: %d] is not set, defaulting to POST", w.Type, w.URL, w.ID)
fallthrough
case http.MethodPost:
switch w.ContentType {
case webhook_model.ContentTypeJSON:
req, err = http.NewRequest("POST", w.URL, strings.NewReader(t.PayloadContent))
if err != nil {
return nil, nil, err
}
req.Header.Set("Content-Type", "application/json")
case webhook_model.ContentTypeForm:
forms := url.Values{
"payload": []string{t.PayloadContent},
}
req, err = http.NewRequest("POST", w.URL, strings.NewReader(forms.Encode()))
if err != nil {
return nil, nil, err
}
req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
default:
return nil, nil, fmt.Errorf("invalid content type: %v", w.ContentType)
}
case http.MethodGet:
u, err := url.Parse(w.URL)
if err != nil {
return nil, nil, fmt.Errorf("invalid URL: %w", err)
}
vals := u.Query()
vals["payload"] = []string{t.PayloadContent}
u.RawQuery = vals.Encode()
req, err = http.NewRequest("GET", u.String(), nil)
if err != nil {
return nil, nil, err
}
case http.MethodPut:
switch w.Type {
case webhook_module.MATRIX: // used when t.Version == 1
txnID, err := getMatrixTxnID([]byte(t.PayloadContent))
if err != nil {
return nil, nil, err
}
url := fmt.Sprintf("%s/%s", w.URL, url.PathEscape(txnID))
req, err = http.NewRequest("PUT", url, strings.NewReader(t.PayloadContent))
if err != nil {
return nil, nil, err
}
default:
return nil, nil, fmt.Errorf("invalid http method: %v", w.HTTPMethod)
}
default:
return nil, nil, fmt.Errorf("invalid http method: %v", w.HTTPMethod)
}
body = []byte(t.PayloadContent)
return req, body, addDefaultHeaders(req, []byte(w.Secret), t, body)
}
func addDefaultHeaders(req *http.Request, secret []byte, t *webhook_model.HookTask, payloadContent []byte) error {
var signatureSHA1 string
var signatureSHA256 string
if len(secret) > 0 {
sig1 := hmac.New(sha1.New, secret)
sig256 := hmac.New(sha256.New, secret)
_, err := io.MultiWriter(sig1, sig256).Write(payloadContent)
if err != nil {
// this error should never happen, since the hashes are writing to []byte and always return a nil error.
return fmt.Errorf("prepareWebhooks.sigWrite: %w", err)
}
signatureSHA1 = hex.EncodeToString(sig1.Sum(nil))
signatureSHA256 = hex.EncodeToString(sig256.Sum(nil))
}
event := t.EventType.Event()
eventType := string(t.EventType)
req.Header.Add("X-Gitea-Delivery", t.UUID)
req.Header.Add("X-Gitea-Event", event)
req.Header.Add("X-Gitea-Event-Type", eventType)
req.Header.Add("X-Gitea-Signature", signatureSHA256)
req.Header.Add("X-Gogs-Delivery", t.UUID)
req.Header.Add("X-Gogs-Event", event)
req.Header.Add("X-Gogs-Event-Type", eventType)
req.Header.Add("X-Gogs-Signature", signatureSHA256)
req.Header.Add("X-Hub-Signature", "sha1="+signatureSHA1)
req.Header.Add("X-Hub-Signature-256", "sha256="+signatureSHA256)
req.Header["X-GitHub-Delivery"] = []string{t.UUID}
req.Header["X-GitHub-Event"] = []string{event}
req.Header["X-GitHub-Event-Type"] = []string{eventType}
return nil
}
// Deliver creates the [http.Request] (depending on the webhook type), sends it
// and records the status and response.
func Deliver(ctx context.Context, t *webhook_model.HookTask) error {
w, err := webhook_model.GetWebhookByID(ctx, t.HookID)
if err != nil {
return err
}
defer func() {
err := recover()
if err == nil {
return
}
// There was a panic whilst delivering a hook...
log.Error("PANIC whilst trying to deliver webhook task[%d] to webhook %s Panic: %v\nStacktrace: %s", t.ID, w.URL, err, log.Stack(2))
}()
t.IsDelivered = true
newRequest := webhookRequesters[w.Type]
if t.PayloadVersion == 1 || newRequest == nil {
newRequest = newDefaultRequest
}
req, body, err := newRequest(ctx, w, t)
if err != nil {
return fmt.Errorf("cannot create http request for webhook %s[%d %s]: %w", w.Type, w.ID, w.URL, err)
}
// Record delivery information.
t.RequestInfo = &webhook_model.HookRequest{
URL: req.URL.String(),
HTTPMethod: req.Method,
Headers: map[string]string{},
Body: string(body),
}
for k, vals := range req.Header {
t.RequestInfo.Headers[k] = strings.Join(vals, ",")
}
// Add Authorization Header
authorization, err := w.HeaderAuthorization()
if err != nil {
return fmt.Errorf("cannot get Authorization header for webhook %s[%d %s]: %w", w.Type, w.ID, w.URL, err)
}
if authorization != "" {
req.Header.Set("Authorization", authorization)
t.RequestInfo.Headers["Authorization"] = "******"
}
t.ResponseInfo = &webhook_model.HookResponse{
Headers: map[string]string{},
}
// OK We're now ready to attempt to deliver the task - we must double check that it
// has not been delivered in the meantime
updated, err := webhook_model.MarkTaskDelivered(ctx, t)
if err != nil {
log.Error("MarkTaskDelivered[%d]: %v", t.ID, err)
return fmt.Errorf("unable to mark task[%d] delivered in the db: %w", t.ID, err)
}
if !updated {
// This webhook task has already been attempted to be delivered or is in the process of being delivered
log.Trace("Webhook Task[%d] already delivered", t.ID)
return nil
}
// All code from this point will update the hook task
defer func() {
t.Delivered = timeutil.TimeStampNanoNow()
if t.IsSucceed {
log.Trace("Hook delivered: %s", t.UUID)
} else if !w.IsActive {
log.Trace("Hook delivery skipped as webhook is inactive: %s", t.UUID)
} else {
log.Trace("Hook delivery failed: %s", t.UUID)
}
if err := webhook_model.UpdateHookTask(ctx, t); err != nil {
log.Error("UpdateHookTask [%d]: %v", t.ID, err)
}
// Update webhook last delivery status.
if t.IsSucceed {
w.LastStatus = webhook_module.HookStatusSucceed
} else {
w.LastStatus = webhook_module.HookStatusFail
}
if err = webhook_model.UpdateWebhookLastStatus(ctx, w); err != nil {
log.Error("UpdateWebhookLastStatus: %v", err)
return
}
}()
if setting.DisableWebhooks {
return fmt.Errorf("webhook task skipped (webhooks disabled): [%d]", t.ID)
}
if !w.IsActive {
log.Trace("Webhook %s in Webhook Task[%d] is not active", w.URL, t.ID)
return nil
}
resp, err := webhookHTTPClient.Do(req.WithContext(ctx))
if err != nil {
t.ResponseInfo.Body = fmt.Sprintf("Delivery: %v", err)
return fmt.Errorf("unable to deliver webhook task[%d] in %s due to error in http client: %w", t.ID, w.URL, err)
}
defer resp.Body.Close()
// Status code is 20x can be seen as succeed.
t.IsSucceed = resp.StatusCode/100 == 2
t.ResponseInfo.Status = resp.StatusCode
for k, vals := range resp.Header {
t.ResponseInfo.Headers[k] = strings.Join(vals, ",")
}
p, err := io.ReadAll(resp.Body)
if err != nil {
t.ResponseInfo.Body = fmt.Sprintf("read body: %s", err)
return fmt.Errorf("unable to deliver webhook task[%d] in %s as unable to read response body: %w", t.ID, w.URL, err)
}
t.ResponseInfo.Body = string(p)
return nil
}
var (
webhookHTTPClient *http.Client
once sync.Once
hostMatchers []glob.Glob
)
func webhookProxy(allowList *hostmatcher.HostMatchList) func(req *http.Request) (*url.URL, error) {
if setting.Webhook.ProxyURL == "" {
return proxy.Proxy()
}
once.Do(func() {
for _, h := range setting.Webhook.ProxyHosts {
if g, err := glob.Compile(h); err == nil {
hostMatchers = append(hostMatchers, g)
} else {
log.Error("glob.Compile %s failed: %v", h, err)
}
}
})
return func(req *http.Request) (*url.URL, error) {
for _, v := range hostMatchers {
if v.Match(req.URL.Host) {
if !allowList.MatchHostName(req.URL.Host) {
return nil, fmt.Errorf("webhook can only call allowed HTTP servers (check your %s setting), deny '%s'", allowList.SettingKeyHint, req.URL.Host)
}
return http.ProxyURL(setting.Webhook.ProxyURLFixed)(req)
}
}
return http.ProxyFromEnvironment(req)
}
}
// Init starts the hooks delivery thread
func Init() error {
timeout := time.Duration(setting.Webhook.DeliverTimeout) * time.Second
allowedHostListValue := setting.Webhook.AllowedHostList
if allowedHostListValue == "" {
allowedHostListValue = hostmatcher.MatchBuiltinExternal
}
allowedHostMatcher := hostmatcher.ParseHostMatchList("webhook.ALLOWED_HOST_LIST", allowedHostListValue)
webhookHTTPClient = &http.Client{
Timeout: timeout,
Transport: &http.Transport{
TLSClientConfig: &tls.Config{InsecureSkipVerify: setting.Webhook.SkipTLSVerify},
Proxy: webhookProxy(allowedHostMatcher),
DialContext: hostmatcher.NewDialContextWithProxy("webhook", allowedHostMatcher, nil, setting.Webhook.ProxyURLFixed),
},
}
hookQueue = queue.CreateUniqueQueue(graceful.GetManager().ShutdownContext(), "webhook_sender", handler)
if hookQueue == nil {
return fmt.Errorf("unable to create webhook_sender queue")
}
go graceful.GetManager().RunWithCancel(hookQueue)
go graceful.GetManager().RunWithShutdownContext(populateWebhookSendingQueue)
return nil
}
func populateWebhookSendingQueue(ctx context.Context) {
ctx, _, finished := process.GetManager().AddContext(ctx, "Webhook: Populate sending queue")
defer finished()
lowerID := int64(0)
for {
taskIDs, err := webhook_model.FindUndeliveredHookTaskIDs(ctx, lowerID)
if err != nil {
log.Error("Unable to populate webhook queue as FindUndeliveredHookTaskIDs failed: %v", err)
return
}
if len(taskIDs) == 0 {
return
}
lowerID = taskIDs[len(taskIDs)-1]
for _, taskID := range taskIDs {
select {
case <-ctx.Done():
log.Warn("Shutdown before Webhook Sending queue finishing being populated")
return
default:
}
if err := enqueueHookTask(taskID); err != nil {
log.Error("Unable to push HookTask[%d] to the Webhook Sending queue: %v", taskID, err)
}
}
}
}