From fdd4e9141ba63822e3daeb2f3ddc66fb0c9f80e7 Mon Sep 17 00:00:00 2001
From: Danijel Martinek <danijel@fraqtal.xyz>
Date: Wed, 6 May 2026 23:41:27 +0200
Subject: [PATCH] feat(core-shared): add ILogger interface + NoopLogger

---
 .../src/instrumentation/logger.interface.ts   | 23 +++++++++++++
 .../src/instrumentation/noop-logger.test.ts   | 34 +++++++++++++++++++
 .../src/instrumentation/noop-logger.ts        | 12 +++++++
 3 files changed, 69 insertions(+)
 create mode 100644 packages/core-shared/src/instrumentation/logger.interface.ts
 create mode 100644 packages/core-shared/src/instrumentation/noop-logger.test.ts
 create mode 100644 packages/core-shared/src/instrumentation/noop-logger.ts

diff --git a/packages/core-shared/src/instrumentation/logger.interface.ts b/packages/core-shared/src/instrumentation/logger.interface.ts
new file mode 100644
index 0000000..49762c9
--- /dev/null
+++ b/packages/core-shared/src/instrumentation/logger.interface.ts
@@ -0,0 +1,23 @@
+export type Breadcrumb = {
+  category: string;
+  message: string;
+  level?: "info" | "warning" | "error";
+  data?: Record<string, unknown>;
+};
+
+export type CaptureContext = {
+  tags?: Record<string, string>;
+  extras?: Record<string, unknown>;
+  fingerprint?: string[];
+};
+
+export interface ILogger {
+  captureException(err: unknown, ctx?: CaptureContext): void;
+  captureMessage(
+    msg: string,
+    level?: "info" | "warning" | "error",
+    ctx?: CaptureContext,
+  ): void;
+  addBreadcrumb(b: Breadcrumb): void;
+  setUser(user: { id: string } | null): void;
+}
diff --git a/packages/core-shared/src/instrumentation/noop-logger.test.ts b/packages/core-shared/src/instrumentation/noop-logger.test.ts
new file mode 100644
index 0000000..3f00909
--- /dev/null
+++ b/packages/core-shared/src/instrumentation/noop-logger.test.ts
@@ -0,0 +1,34 @@
+import { describe, it, expect } from "vitest";
+import { NoopLogger } from "@/instrumentation/noop-logger";
+
+describe("NoopLogger", () => {
+  it("captureException is callable with err and ctx", () => {
+    const logger = new NoopLogger();
+    expect(() => logger.captureException(new Error("x"))).not.toThrow();
+    expect(() =>
+      logger.captureException(new Error("x"), { tags: { feature: "blog" } }),
+    ).not.toThrow();
+  });
+
+  it("captureMessage is callable", () => {
+    const logger = new NoopLogger();
+    expect(() => logger.captureMessage("hello")).not.toThrow();
+    expect(() => logger.captureMessage("hello", "warning")).not.toThrow();
+    expect(() =>
+      logger.captureMessage("hello", "error", { extras: { foo: 1 } }),
+    ).not.toThrow();
+  });
+
+  it("addBreadcrumb is callable", () => {
+    const logger = new NoopLogger();
+    expect(() =>
+      logger.addBreadcrumb({ category: "test", message: "x" }),
+    ).not.toThrow();
+  });
+
+  it("setUser accepts opaque id and null", () => {
+    const logger = new NoopLogger();
+    expect(() => logger.setUser({ id: "u1" })).not.toThrow();
+    expect(() => logger.setUser(null)).not.toThrow();
+  });
+});
diff --git a/packages/core-shared/src/instrumentation/noop-logger.ts b/packages/core-shared/src/instrumentation/noop-logger.ts
new file mode 100644
index 0000000..1b7af61
--- /dev/null
+++ b/packages/core-shared/src/instrumentation/noop-logger.ts
@@ -0,0 +1,12 @@
+import type { ILogger, Breadcrumb, CaptureContext } from "./logger.interface";
+
+export class NoopLogger implements ILogger {
+  captureException(_err: unknown, _ctx?: CaptureContext): void {}
+  captureMessage(
+    _msg: string,
+    _level?: "info" | "warning" | "error",
+    _ctx?: CaptureContext,
+  ): void {}
+  addBreadcrumb(_b: Breadcrumb): void {}
+  setUser(_user: { id: string } | null): void {}
+}