order sagas

pkg/flow/hooks.go

@@ -0,0 +1,89 @@
+package flow
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+// RegisterBuiltinHooks adds the generic hooks every deployment can use: "log"
+// (structured log line) and "webhook" (HTTP POST of the event). Domain packages
+// register their own hooks (e.g. "amqp_emit") on the same registry.
+func RegisterBuiltinHooks(reg *Registry) {
+	reg.Hook("log", logHook)
+	reg.Hook("noop", func(context.Context, *State, HookInfo, json.RawMessage) error { return nil })
+	reg.Hook("webhook", webhookHook(&http.Client{Timeout: 10 * time.Second}))
+}
+
+// logHook emits a structured log line for the step/phase. Params (optional):
+//
+//	{"message": "custom text"}
+func logHook(_ context.Context, st *State, info HookInfo, params json.RawMessage) error {
+	msg := "flow hook"
+	if len(params) > 0 {
+		var p struct {
+			Message string `json:"message"`
+		}
+		if err := json.Unmarshal(params, &p); err == nil && p.Message != "" {
+			msg = p.Message
+		}
+	}
+	args := []any{"step", info.Step, "phase", info.Phase, "id", st.ID}
+	if info.Err != nil {
+		args = append(args, "err", info.Err)
+	}
+	st.Logger.Info(msg, args...)
+	return nil
+}
+
+// webhookHook POSTs a JSON event to a configured URL. Params:
+//
+//	{"url": "https://...", "headers": {"X-Token": "..."}}
+//
+// The body is {step, phase, id, error, vars}. Returned as a closure so the HTTP
+// client (and its timeout/transport) is shared across invocations.
+func webhookHook(client *http.Client) Hook {
+	return func(ctx context.Context, st *State, info HookInfo, params json.RawMessage) error {
+		var p struct {
+			URL     string            `json:"url"`
+			Headers map[string]string `json:"headers,omitempty"`
+		}
+		if err := json.Unmarshal(params, &p); err != nil {
+			return fmt.Errorf("webhook: bad params: %w", err)
+		}
+		if p.URL == "" {
+			return fmt.Errorf("webhook: missing url")
+		}
+		errStr := ""
+		if info.Err != nil {
+			errStr = info.Err.Error()
+		}
+		body, _ := json.Marshal(map[string]any{
+			"step":  info.Step,
+			"phase": info.Phase,
+			"id":    st.ID,
+			"error": errStr,
+			"vars":  st.Vars,
+		})
+		req, err := http.NewRequestWithContext(ctx, http.MethodPost, p.URL, bytes.NewReader(body))
+		if err != nil {
+			return err
+		}
+		req.Header.Set("Content-Type", "application/json")
+		for k, v := range p.Headers {
+			req.Header.Set(k, v)
+		}
+		resp, err := client.Do(req)
+		if err != nil {
+			return err
+		}
+		defer resp.Body.Close()
+		if resp.StatusCode >= 300 {
+			return fmt.Errorf("webhook: %s returned %d", p.URL, resp.StatusCode)
+		}
+		return nil
+	}
+}