Add child context logger to the ctx.console

.changeset/fuzzy-logger-context.md

@@ -0,0 +1,5 @@
+---
+"@restatedev/restate-sdk": patch
+---
+
+Add `ctx.console.child(...)` for immutable, replay-aware logger context enrichment.

packages/examples/node/package.json

@@ -13,6 +13,7 @@
     "greeter": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/greeter.ts",
     "greeter_hooks": "RESTATE_LOGGING=ERROR tsx --tsconfig ./tsconfig.json ./src/greeter_with_hooks.ts",
     "greeter_http1": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/greeter_http1.ts",
+    "logger_context": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/logger_context.ts",
     "preview_serde": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/preview_serde.ts",
     "zgreeter": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/zod_greeter.ts",
     "workflow": "RESTATE_LOGGING=debug tsx --tsconfig ./tsconfig.json ./src/workflow.ts",

packages/examples/node/src/logger_context.ts

@@ -0,0 +1,71 @@
+import { service, serve, type Context } from "@restatedev/restate-sdk";
+
+interface CheckoutRequest {
+  orderId: string;
+  customerId: string;
+  paymentMethodId: string;
+}
+
+interface PaymentResult {
+  paymentId: string;
+}
+
+const checkout = service({
+  name: "checkout",
+  handlers: {
+    submit: async (ctx: Context, input: CheckoutRequest) => {
+      let contextLogger = ctx.console.child({
+        orderId: input.orderId,
+        customerId: input.customerId,
+      });
+
+      contextLogger.info("checkout started");
+
+      const payment = await ctx.run("charge payment", async () => {
+        return await chargePayment(input);
+      });
+
+      // This is rebuilt on replay from the journaled ctx.run result.
+      contextLogger = contextLogger.child({ paymentId: payment.paymentId });
+      contextLogger.info("payment charged");
+
+      const shipment = await ctx.run("create shipment", async () => {
+        return await createShipment(input.orderId);
+      });
+
+      contextLogger
+        .child({ shipmentId: shipment.shipmentId })
+        .info("shipment created");
+
+      return {
+        orderId: input.orderId,
+        paymentId: payment.paymentId,
+        shipmentId: shipment.shipmentId,
+      };
+    },
+  },
+});
+
+export type Checkout = typeof checkout;
+
+/**
+ * Simulates charging a payment provider and returns a durable payment id.
+ */
+async function chargePayment(input: CheckoutRequest): Promise<PaymentResult> {
+  return {
+    paymentId: `payment-${input.paymentMethodId}`,
+  };
+}
+
+/**
+ * Simulates creating a shipment and returns a durable shipment id.
+ */
+async function createShipment(
+  orderId: string
+): Promise<{ shipmentId: string }> {
+  return {
+    shipmentId: `shipment-${orderId}`,
+  };
+}
+
+serve({ services: [checkout] });