README.md

🥯 bun-bagel: The Bun fetch mocker with a hole lot of flavor.

---

bun-bagel is a mocking library specifically designed for Bun's fetch API. It enables developers to easily intercept fetch requests and provide custom mock responses, streamlining the development and testing process of Bun applications.

⚠️ The library is yet only experimental and might change over time.

📖 Usage

import { mock } from "bun-bagel";

// Register the mock for the example URL.
mock("https://example.com/api/users/*", { data: { name: "Foo" } });

// Make a fetch request to the mocked URL
const response = await fetch("https://example.com/api/users/123");

// Print the response body
console.log(await response.json());

Output:

{ name: "Foo" }

🚀 Why bun-bagel?

• Lightweight and easy to use: Get started in minutes with a simple, intuitive API.
• Flexible and powerful: Handle a wide range of mocking scenarios with ease.
• Built for Bun: Seamlessly integrates with Bun's runtime for a smooth developer experience.
• Thoroughly tested: Comes with a comprehensive test suite to ensure reliability.

📚 Installation

bun install bun-bagel

🧪 Examples

Bun Unit Tests

import { describe, test, expect, afterEach } from "bun:test";
import { mock, clearMocks } from "bun-bagel";

describe("Unit Test", () => {

    afterEach(() => {
        clearMocks();
    });

    test("Mock Fetch", async () => {
        // Register the mock for the example URL.
        mock("https://example.com/api/users/*", { data: { name: "Foo" } });

        // Call a function that uses the fetch method.
        const response = await fetchSomeData();

        // Print the response body
        console.log(await response.json()); // => { name: "Foo" }
    });
});

Mock by headers and method

import { mock } from "bun-bagel";
import type { MockOptions } from "bun-bagel";

const options: MockOptions = {
    method: "POST",
    headers: { "x-foo-bar": "baz" },
    response: {
        data: { name: "Foo" },
    }
};

// Register the mock for the example URL.
mock("https://example.com/api/users/*", options);

// Make a fetch request to the mocked URL
const response = await fetch("https://example.com/api/users/123", { headers: { "x-foo-bar": "baz" } });

// Requests without the headers will not be matched.
const response2 = await fetch("https://example.com/api/users/123");

// Check the response body.
console.log(await response.json()); // => { name: "Foo" }

Mock response status and headers

import { mock } from "bun-bagel";
import type { MockOptions } from "bun-bagel";

const options: MockOptions = {
    response: {
        data: { name: "Foo" },
        status: 404,
        headers: { "x-foo-bar": "baz" },
    }
};

// Register the mock for the example URL.
mock("https://example.com/api/users/*", options);

// Make a fetch request to the mocked URL
const response = await fetch("https://example.com/api/users/123");

// Check the status and headers.
console.log(response.status); // => 404
console.log(response.headers); // => { "x-foo-bar": "baz" }

🤝 Contributing

Contributions are welcome! Please see the CONTRIBUTING.md file for details.

🔨 Development

To contribute to bun-bagel, follow these steps:

1. Clone the repository: git clone https://github.com/DRFR0ST/bun-bagel.git
2. Install dependencies: bun install
3. Run tests: bun test
4. Run linter & formatter: bun run check
5. Build the library: bun run build

Note

You can also play around with bun-bagel by making changes in the /sandbox directory and running bun run sandbox. Make sure to build the library after making changes in the /src directory.

🤝 Community

Join the discussion on the GitHub Discussions page.

📝 License

This project is licensed under the terms of the MIT license. See the LICENSE file for details.

📢 Thanks to all contributors for making this library better!

🤖 Thanks to Gemini for generating a part of the initial code and readme, and helped brainstorm the idea.