gitea-github-proxy/api/webhook_manager.go

package api

import (
	"bytes"
	giteaTypes "code.gitea.io/gitea/modules/structs"
	"encoding/json"
	"git.lumeweb.com/LumeWeb/gitea-github-proxy/config"
	"git.lumeweb.com/LumeWeb/gitea-github-proxy/db/model"
	"github.com/fatih/structs"
	"go.uber.org/zap"
	"gorm.io/gorm"
	"io"
	"net/http"
	"regexp"
	"strings"
)

type WebhookManager struct {
	config *config.Config
	db     *gorm.DB
	logger *zap.Logger
}

type IncomingWebhookData struct {
	Headers http.Header
}

func NewWebhookManager(cfg *config.Config, db *gorm.DB, logger *zap.Logger) *WebhookManager {
	return &WebhookManager{config: cfg, db: db, logger: logger}
}

func (whm *WebhookManager) HandlePullRequest(request *giteaTypes.PullRequestPayload, r *http.Request) {
	ghEvent := convertPullRequestEvent(request)
	githubAction := translatePrAction(request.Action)
	r.Header.Set("X-GitHub-Event", githubAction)

	whm.sendWebhooks(ghEvent, r)
}
func (whm *WebhookManager) sendWebhooks(request interface{}, r *http.Request) {
	var apps []model.Apps
	result := whm.db.Find(&apps)
	if result.Error != nil {
		whm.logger.Error("Failed to query apps", zap.Error(result.Error))
		return
	}
	for _, app := range apps {
		go func(app model.Apps) {

			rawMap := structs.New(request).Map()

			rawMap["installation"] = struct {
				ID uint `json:"id"`
			}{ID: app.ID}

			payloadBytes, err := json.Marshal(rawMap)
			if err != nil {
				whm.logger.Error("Failed to marshal payload", zap.Error(err))
				return
			}

			req, err := http.NewRequest("POST", app.WebhookUrl, bytes.NewBuffer(payloadBytes))
			if err != nil {
				whm.logger.Error("Failed to create request", zap.Error(err), zap.String("url", app.WebhookUrl))
				return
			}

			req.Header.Set("Content-Type", "application/json")

			for key, values := range r.Header {
				for _, value := range values {
					req.Header.Add(key, value)
				}
			}

			payload := toNormalizedJson(payloadBytes)

			signature := generatePayloadSignature(payload, app.WebhookSecret)
			req.Header.Set("X-Hub-Signature-256", signature)

			client := &http.Client{}
			resp, err := client.Do(req)
			if err != nil {
				whm.logger.Error("Failed to send webhook", zap.Error(err), zap.String("url", app.WebhookUrl))
				return
			}
			defer func(Body io.ReadCloser) {
				err := Body.Close()
				if err != nil {
					whm.logger.Error("Failed to close response body", zap.Error(err))
				}
			}(resp.Body)

			if resp.StatusCode >= 200 && resp.StatusCode < 300 {
				whm.logger.Info("Webhook sent successfully", zap.String("url", app.WebhookUrl))
			} else {
				whm.logger.Error("Webhook failed", zap.String("url", app.WebhookUrl), zap.Int("status", resp.StatusCode))
			}
		}(app)
	}
}

/*
* Ported from https://github.com/octokit/webhooks.js/blob/984f3f51e077dbc7637aa55406c3bb114dbb7f82/src/to-normalized-json-string.ts
 */

func toNormalizedJson(payload []byte) []byte {
	jsonString := string(payload)

	// Regex to find Unicode escape sequences
	re := regexp.MustCompile(`\\u([\da-fA-F]{4})`)

	// Function to convert found sequences to uppercase
	replaceFunc := func(match string) string {
		parts := strings.Split(match, "\\u")
		// Convert the Unicode sequence part to uppercase
		return parts[0] + "\\u" + strings.ToUpper(parts[1])
	}

	// Replace the matches in the jsonString
	normalizedString := re.ReplaceAllStringFunc(jsonString, replaceFunc)

	return []byte(normalizedString)
}