|
| 1 | +package webhook |
| 2 | + |
| 3 | +import ( |
| 4 | + "context" |
| 5 | + "encoding/json" |
| 6 | + "fmt" |
| 7 | + "log/slog" |
| 8 | + "net" |
| 9 | + "net/http" |
| 10 | + "strings" |
| 11 | + |
| 12 | + "hubproxy/internal/storage" |
| 13 | + |
| 14 | + "github.com/prometheus/client_golang/prometheus" |
| 15 | + "github.com/prometheus/client_golang/prometheus/promauto" |
| 16 | +) |
| 17 | + |
| 18 | +var ( |
| 19 | + webhookForwardedEvents = promauto.NewCounter( |
| 20 | + prometheus.CounterOpts{ |
| 21 | + Name: "hubproxy_webhook_forwarded_events_total", |
| 22 | + Help: "Total number of webhook events forwarded to the target", |
| 23 | + }, |
| 24 | + ) |
| 25 | + |
| 26 | + webhookForwardingErrors = promauto.NewCounter( |
| 27 | + prometheus.CounterOpts{ |
| 28 | + Name: "hubproxy_webhook_forwarding_errors_total", |
| 29 | + Help: "Total number of webhook forwarding errors", |
| 30 | + }, |
| 31 | + ) |
| 32 | +) |
| 33 | + |
| 34 | +type WebhookForwarder struct { |
| 35 | + storage storage.Storage |
| 36 | + metricsCollector *storage.DBMetricsCollector |
| 37 | + httpClient *http.Client |
| 38 | + targetURL string |
| 39 | + logger *slog.Logger |
| 40 | + queue chan struct{} |
| 41 | +} |
| 42 | + |
| 43 | +type WebhookForwarderOptions struct { |
| 44 | + Storage storage.Storage |
| 45 | + MetricsCollector *storage.DBMetricsCollector |
| 46 | + HTTPClient *http.Client |
| 47 | + TargetURL string |
| 48 | + Logger *slog.Logger |
| 49 | +} |
| 50 | + |
| 51 | +func NewWebhookForwarder(opts WebhookForwarderOptions) *WebhookForwarder { |
| 52 | + if opts.TargetURL == "" { |
| 53 | + panic("target URL is required") |
| 54 | + } |
| 55 | + if opts.Storage == nil { |
| 56 | + panic("storage is required") |
| 57 | + } |
| 58 | + if opts.Logger == nil { |
| 59 | + opts.Logger = slog.Default() |
| 60 | + } |
| 61 | + |
| 62 | + httpClient := opts.HTTPClient |
| 63 | + |
| 64 | + // Swap out HTTP client to use Unix socket |
| 65 | + if strings.HasPrefix(opts.TargetURL, "unix://") { |
| 66 | + socketPath := strings.TrimPrefix(opts.TargetURL, "unix://") |
| 67 | + httpClient = &http.Client{ |
| 68 | + Transport: &http.Transport{ |
| 69 | + DialContext: func(ctx context.Context, _, addr string) (net.Conn, error) { |
| 70 | + return net.Dial("unix", socketPath) |
| 71 | + }, |
| 72 | + }, |
| 73 | + } |
| 74 | + } |
| 75 | + |
| 76 | + // Use default HTTP client if not provided |
| 77 | + if httpClient == nil { |
| 78 | + httpClient = &http.Client{} |
| 79 | + } |
| 80 | + |
| 81 | + return &WebhookForwarder{ |
| 82 | + targetURL: opts.TargetURL, |
| 83 | + httpClient: httpClient, |
| 84 | + storage: opts.Storage, |
| 85 | + metricsCollector: opts.MetricsCollector, |
| 86 | + logger: opts.Logger, |
| 87 | + queue: make(chan struct{}, 1), // Buffer size 1 to allow one pending job |
| 88 | + } |
| 89 | +} |
| 90 | + |
| 91 | +// TargetURL returns the configured target URL |
| 92 | +func (f *WebhookForwarder) TargetURL() string { |
| 93 | + return f.targetURL |
| 94 | +} |
| 95 | + |
| 96 | +func (f *WebhookForwarder) forwardEvent(ctx context.Context, event *storage.Event) { |
| 97 | + var targetURL string |
| 98 | + // http.NewRequest still needs a valid http URI, make a fake one for unix socket path |
| 99 | + if strings.HasPrefix(f.targetURL, "unix://") { |
| 100 | + targetURL = "http://127.0.0.1/webhook" |
| 101 | + } else { |
| 102 | + targetURL = f.targetURL |
| 103 | + } |
| 104 | + |
| 105 | + req, err := http.NewRequest(http.MethodPost, targetURL, strings.NewReader(string(event.Payload))) |
| 106 | + if err != nil { |
| 107 | + webhookForwardingErrors.Inc() |
| 108 | + f.logger.Error("failed to create request", "targetURL", targetURL, "error", err) |
| 109 | + return |
| 110 | + } |
| 111 | + |
| 112 | + var headers map[string][]string |
| 113 | + err = json.Unmarshal(event.Headers, &headers) |
| 114 | + if err != nil { |
| 115 | + webhookForwardingErrors.Inc() |
| 116 | + f.logger.Error("failed to parse headers", "error", err) |
| 117 | + return |
| 118 | + } |
| 119 | + |
| 120 | + for name, values := range headers { |
| 121 | + for _, value := range values { |
| 122 | + req.Header.Add(name, value) |
| 123 | + } |
| 124 | + } |
| 125 | + |
| 126 | + if req.Header.Get("Content-Type") != "application/json" { |
| 127 | + f.logger.Warn("Content-Type header is not application/json", "Content-Type", req.Header.Get("Content-Type")) |
| 128 | + } |
| 129 | + if req.Header.Get("X-Github-Event") == "" { |
| 130 | + f.logger.Warn("X-Github-Event header is not set", "X-Github-Event", req.Header.Get("X-Github-Event")) |
| 131 | + } |
| 132 | + if req.Header.Get("X-Github-Delivery") == "" { |
| 133 | + f.logger.Warn("X-Github-Delivery header is not set", "X-Github-Delivery", req.Header.Get("X-Github-Delivery")) |
| 134 | + } |
| 135 | + if req.Header.Get("X-Hub-Signature-256") == "" { |
| 136 | + f.logger.Warn("X-Hub-Signature-256 header is not set", "X-Hub-Signature-256", req.Header.Get("X-Hub-Signature-256")) |
| 137 | + } |
| 138 | + |
| 139 | + resp, err := f.httpClient.Do(req) |
| 140 | + if err != nil { |
| 141 | + webhookForwardingErrors.Inc() |
| 142 | + f.logger.Error("failed to forward request", "targetURL", targetURL, "error", err) |
| 143 | + return |
| 144 | + } |
| 145 | + defer resp.Body.Close() |
| 146 | + |
| 147 | + if resp.StatusCode >= 400 { |
| 148 | + webhookForwardingErrors.Inc() |
| 149 | + f.logger.Error("target returned error", "status", resp.Status, "targetURL", targetURL) |
| 150 | + return |
| 151 | + } |
| 152 | + |
| 153 | + webhookForwardedEvents.Inc() |
| 154 | + |
| 155 | + err = f.storage.MarkForwarded(ctx, event.ID) |
| 156 | + if err != nil { |
| 157 | + f.logger.Error("error marking event as forwarded", "error", err) |
| 158 | + } |
| 159 | +} |
| 160 | + |
| 161 | +func (f *WebhookForwarder) ProcessEvents(ctx context.Context) error { |
| 162 | + // Don't ever create a WebhookForwarder if there's no target URL |
| 163 | + if f.targetURL == "" { |
| 164 | + panic("target URL is not set") |
| 165 | + } |
| 166 | + |
| 167 | + f.logger.Debug("processing webhook events from database") |
| 168 | + |
| 169 | + // TODO: Only select events WEHRE forwarded_at IS NULL |
| 170 | + events, _, err := f.storage.ListEvents(ctx, storage.QueryOptions{}) |
| 171 | + if err != nil { |
| 172 | + return fmt.Errorf("listing events: %w", err) |
| 173 | + } |
| 174 | + |
| 175 | + if len(events) == 0 { |
| 176 | + f.logger.Debug("no events to forward") |
| 177 | + return nil |
| 178 | + } |
| 179 | + |
| 180 | + f.logger.Info("forwarding webhook events", "count", len(events)) |
| 181 | + |
| 182 | + for _, event := range events { |
| 183 | + f.forwardEvent(ctx, event) |
| 184 | + } |
| 185 | + |
| 186 | + f.metricsCollector.EnqueueGatherMetrics(ctx) |
| 187 | + |
| 188 | + return nil |
| 189 | +} |
| 190 | + |
| 191 | +func (f *WebhookForwarder) EnqueueProcessEvents() { |
| 192 | + select { |
| 193 | + case f.queue <- struct{}{}: |
| 194 | + f.logger.Debug("enqueued webhook processing job") |
| 195 | + default: |
| 196 | + f.logger.Debug("webhook processing job already pending") |
| 197 | + } |
| 198 | +} |
| 199 | + |
| 200 | +func (f *WebhookForwarder) StartForwarder(ctx context.Context) { |
| 201 | + go func() { |
| 202 | + for { |
| 203 | + select { |
| 204 | + case <-ctx.Done(): |
| 205 | + f.logger.Debug("stopped webhook forwarder") |
| 206 | + return |
| 207 | + case <-f.queue: |
| 208 | + if err := f.ProcessEvents(ctx); err != nil { |
| 209 | + f.logger.Error("failed to process webhook events", "error", err) |
| 210 | + } |
| 211 | + } |
| 212 | + } |
| 213 | + }() |
| 214 | + |
| 215 | + f.EnqueueProcessEvents() |
| 216 | +} |
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