Files

113 lines
3.1 KiB
Go

// Package handlers contains job.Handler implementations for the jobs module.
// Each file defines exactly one Handler so each can be tested in isolation.
package handlers
import (
"bytes"
"context"
"crypto/hmac"
"crypto/sha256"
"encoding/hex"
"encoding/json"
"fmt"
"io"
"net/http"
"strconv"
"time"
"github.com/yan1h/agent-coding-workflow/internal/infra/clock"
"github.com/yan1h/agent-coding-workflow/internal/jobs"
)
// WebhookConfig is the per-handler webhook config (URL/secret/timeout).
// Topic-whitelist filtering is performed upstream by the WebhookNotifier
// before enqueue, so this handler always delivers what it gets.
type WebhookConfig struct {
URL string
Secret string
Timeout time.Duration
}
// WebhookHandler implements jobs.Handler for the TypeWebhookDeliver type.
type WebhookHandler struct {
cfg WebhookConfig
clk clock.Clock
client *http.Client
}
// NewWebhookHandler constructs a handler with the given config. The handler
// builds a fresh http.Client per dispatch (no keep-alive) since webhook
// frequency is low.
func NewWebhookHandler(cfg WebhookConfig, clk clock.Clock) *WebhookHandler {
if cfg.Timeout <= 0 {
cfg.Timeout = 10 * time.Second
}
if clk == nil {
clk = clock.Real()
}
return &WebhookHandler{
cfg: cfg,
clk: clk,
client: &http.Client{Timeout: cfg.Timeout},
}
}
func (h *WebhookHandler) Type() jobs.JobType { return jobs.TypeWebhookDeliver }
// payloadEnvelope mirrors the JSON shape the webhook receiver gets. Topic is
// surfaced as a header AND in the body for convenience.
type payloadEnvelope struct {
Topic string `json:"topic"`
}
func (h *WebhookHandler) Handle(ctx context.Context, job jobs.Job) error {
if h.cfg.URL == "" {
return jobs.Permanent(fmt.Errorf("webhook url not configured"))
}
var env payloadEnvelope
if err := json.Unmarshal(job.Payload, &env); err != nil {
return jobs.Permanent(fmt.Errorf("payload not valid json: %w", err))
}
body := []byte(job.Payload)
ts := strconv.FormatInt(h.clk.Now().Unix(), 10)
sig := sign(h.cfg.Secret, ts, body)
req, err := http.NewRequestWithContext(ctx, http.MethodPost, h.cfg.URL, bytes.NewReader(body))
if err != nil {
return fmt.Errorf("build request: %w", err)
}
req.Header.Set("Content-Type", "application/json")
req.Header.Set("User-Agent", "agent-coding-workflow/dev")
req.Header.Set("X-ACW-Topic", env.Topic)
req.Header.Set("X-ACW-Event-Id", job.ID.String())
req.Header.Set("X-ACW-Timestamp", ts)
req.Header.Set("X-ACW-Signature", sig)
resp, err := h.client.Do(req)
if err != nil {
return fmt.Errorf("http: %w", err)
}
defer resp.Body.Close()
if resp.StatusCode >= 200 && resp.StatusCode < 300 {
_, _ = io.Copy(io.Discard, resp.Body)
return nil
}
respBody, _ := io.ReadAll(io.LimitReader(resp.Body, 500))
msg := fmt.Sprintf("%d %s", resp.StatusCode, string(respBody))
if resp.StatusCode >= 400 && resp.StatusCode < 500 {
return jobs.Permanent(fmt.Errorf("%s", msg))
}
return fmt.Errorf("%s", msg)
}
func sign(secret, ts string, body []byte) string {
mac := hmac.New(sha256.New, []byte(secret))
mac.Write([]byte(ts + "."))
mac.Write(body)
return "sha256=" + hex.EncodeToString(mac.Sum(nil))
}