refactor: split gateway server helpers and tests

src/gateway/ws-log.test.ts

@@ -0,0 +1,53 @@
+import { describe, expect, test } from "vitest";
+import {
+  formatForLog,
+  shortId,
+  summarizeAgentEventForWsLog,
+} from "./ws-log.js";
+
+describe("gateway ws log helpers", () => {
+  test("shortId compacts uuids and long strings", () => {
+    expect(shortId("12345678-1234-1234-1234-123456789abc")).toBe(
+      "12345678…9abc",
+    );
+    expect(shortId("a".repeat(30))).toBe("aaaaaaaaaaaa…aaaa");
+    expect(shortId("short")).toBe("short");
+  });
+
+  test("formatForLog formats errors and messages", () => {
+    const err = new Error("boom");
+    err.name = "TestError";
+    expect(formatForLog(err)).toContain("TestError");
+    expect(formatForLog(err)).toContain("boom");
+
+    const obj = { name: "Oops", message: "failed", code: "E1" };
+    expect(formatForLog(obj)).toBe("Oops: failed: code=E1");
+  });
+
+  test("summarizeAgentEventForWsLog extracts useful fields", () => {
+    const summary = summarizeAgentEventForWsLog({
+      runId: "12345678-1234-1234-1234-123456789abc",
+      stream: "assistant",
+      seq: 2,
+      data: { text: "hello world", mediaUrls: ["a", "b"] },
+    });
+    expect(summary).toMatchObject({
+      run: "12345678…9abc",
+      stream: "assistant",
+      aseq: 2,
+      text: "hello world",
+      media: 2,
+    });
+
+    const tool = summarizeAgentEventForWsLog({
+      runId: "run-1",
+      stream: "tool",
+      data: { phase: "start", name: "fetch", toolCallId: "call-1" },
+    });
+    expect(tool).toMatchObject({
+      stream: "tool",
+      tool: "start:fetch",
+      call: "call-1",
+    });
+  });
+});