🥯 The Bun fetch mocker with a hole lot of flavor.
npm install bun-bagel
---
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.
:warning: The library is yet only experimental and might change over time.
``ts
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" }
- 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.
bun install bun-bagel
ts
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" }
});
});
`$3
ts
import { describe, test, expect, afterEach } from "bun:test";
import { mock, clearMocks } from "bun-bagel";describe("Unit Test", () => {
test("Mock Fetch", async () => {
// Register the mock for the example URL.
mock("https://example.com/api/users/*", { data: Bun.file("./my-file.json") });
// Call a function that uses the fetch method.
const response = await fetchSomeData();
const blob = await response.blob();
// Print the body
console.log(await blob.json()); // => { name: "Bar" }
});
});
`$3
ts
import { mock } from "bun-bagel";
import type { MockOptions } from "bun-bagel";const options: MockOptions = {
method: "POST",
headers: new 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: new 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" }
`$3
ts
import { mock } from "bun-bagel";
import type { MockOptions } from "bun-bagel";const options: MockOptions = {
response: {
data: { name: "Foo" },
status: 404,
headers: new 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" }
`$3
import { disableRealRequests } from "bun-bagel";disableRealRequests();
await fetch("https://example.com/api/users/123"); // Throws 404 error.
🤝 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:
2. Install dependencies:
3. Run tests:
4. Run linter & formatter:
5. Build the library: > [!NOTE]
>You can also play around with bun-bagel by making changes in the
directory and running bun run sandbox. Make sure to build the library after making changes in the /src` directory.Join the discussion on the GitHub Discussions page.
#### 📢 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.