From 19993c6f5ba490fb4dd077b06b2de3e15b9b5147 Mon Sep 17 00:00:00 2001
From: Kir_Antipov <kp.antipov@gmail.com>
Date: Wed, 14 Dec 2022 15:32:18 +0000
Subject: [PATCH] Added a logger that writes logs to the console

---
 src/utils/logging/console-logger.ts           |  66 +++++++++++
 .../unit/utils/logging/console-logger.spec.ts | 112 ++++++++++++++++++
 2 files changed, 178 insertions(+)
 create mode 100644 src/utils/logging/console-logger.ts
 create mode 100644 tests/unit/utils/logging/console-logger.spec.ts

diff --git a/src/utils/logging/console-logger.ts b/src/utils/logging/console-logger.ts
new file mode 100644
index 0000000..9c51539
--- /dev/null
+++ b/src/utils/logging/console-logger.ts
@@ -0,0 +1,66 @@
+import { Logger } from "./logger";
+import { error, warn, info, debug } from "node:console";
+
+/**
+ * Represents a console-like object.
+ */
+type Console = Omit<Logger, "fatal">;
+
+/**
+ * Default console instance.
+ */
+const CONSOLE_INSTANCE: Console = { error, warn, info, debug };
+
+/**
+ * A logger that writes log messages to the console.
+ */
+export class ConsoleLogger implements Logger {
+    /**
+     * A console instance to log messages to.
+     */
+    private readonly _console: Console;
+
+    /**
+     * Constructs a new {@link ConsoleLogger} instance.
+     *
+     * @param console - Optional custom console object to use for logging.
+     */
+    constructor(console?: Console) {
+        this._console = console || CONSOLE_INSTANCE;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    fatal(message: string | Error): void {
+        this._console.error(message);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    error(message: string | Error): void {
+        this._console.error(message);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    warn(message: string | Error): void {
+        this._console.warn(message);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    info(message: string | Error): void {
+        this._console.info(message);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    debug(message: string | Error): void {
+        this._console.debug(message);
+    }
+}
diff --git a/tests/unit/utils/logging/console-logger.spec.ts b/tests/unit/utils/logging/console-logger.spec.ts
new file mode 100644
index 0000000..cb11452
--- /dev/null
+++ b/tests/unit/utils/logging/console-logger.spec.ts
@@ -0,0 +1,112 @@
+import { ConsoleLogger } from "@/utils/logging/console-logger";
+
+interface MockConsole {
+    error: jest.Mock;
+    warn: jest.Mock;
+    info: jest.Mock;
+    debug: jest.Mock;
+}
+
+function createMockConsole(): MockConsole {
+    return {
+        error: jest.fn(),
+        warn: jest.fn(),
+        info: jest.fn(),
+        debug: jest.fn(),
+    };
+}
+
+describe("ConsoleLogger", () => {
+    describe("constructor", () => {
+        test("constructs a new instance with the provided console", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.fatal("Fatal");
+            logger.error("Error");
+            logger.warn("Warn");
+            logger.info("Info");
+            logger.debug("Debug");
+
+            expect(console.error).toHaveBeenCalledTimes(2);
+            expect(console.error).toHaveBeenNthCalledWith(1, "Fatal");
+            expect(console.error).toHaveBeenNthCalledWith(2, "Error");
+            expect(console.warn).toHaveBeenCalledTimes(1);
+            expect(console.warn).toHaveBeenCalledWith("Warn");
+            expect(console.info).toHaveBeenCalledTimes(1);
+            expect(console.info).toHaveBeenCalledWith("Info");
+            expect(console.debug).toHaveBeenCalledTimes(1);
+            expect(console.debug).toHaveBeenCalledWith("Debug");
+        });
+    });
+
+    describe("fatal", () => {
+        test("redirects the call to console.error", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.fatal("Fatal Error");
+            logger.fatal(new Error("Fatal Error"));
+
+            expect(console.error).toHaveBeenCalledTimes(2);
+            expect(console.error).toHaveBeenNthCalledWith(1, "Fatal Error");
+            expect(console.error).toHaveBeenNthCalledWith(2, new Error("Fatal Error"));
+        });
+    });
+
+    describe("error", () => {
+        test("redirects the call to console.error", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.fatal("Error");
+            logger.fatal(new Error("Error"));
+
+            expect(console.error).toHaveBeenCalledTimes(2);
+            expect(console.error).toHaveBeenNthCalledWith(1, "Error");
+            expect(console.error).toHaveBeenNthCalledWith(2, new Error("Error"));
+        });
+    });
+
+    describe("warn", () => {
+        test("redirects the call to console.warn", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.warn("Warning");
+            logger.warn(new Error("Warning"));
+
+            expect(console.warn).toHaveBeenCalledTimes(2);
+            expect(console.warn).toHaveBeenNthCalledWith(1, "Warning");
+            expect(console.warn).toHaveBeenNthCalledWith(2, new Error("Warning"));
+        });
+    });
+
+    describe("info", () => {
+        test("redirects the call to console.info", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.info("Info");
+            logger.info(new Error("Info"));
+
+            expect(console.info).toHaveBeenCalledTimes(2);
+            expect(console.info).toHaveBeenNthCalledWith(1, "Info");
+            expect(console.info).toHaveBeenNthCalledWith(2, new Error("Info"));
+        });
+    });
+
+    describe("debug", () => {
+        test("redirects the call to console.debug", () => {
+            const console = createMockConsole();
+            const logger = new ConsoleLogger(console);
+
+            logger.debug("Debug Info");
+            logger.debug(new Error("Debug Info"));
+
+            expect(console.debug).toHaveBeenCalledTimes(2);
+            expect(console.debug).toHaveBeenNthCalledWith(1, "Debug Info");
+            expect(console.debug).toHaveBeenNthCalledWith(2, new Error("Debug Info"));
+        });
+    });
+});