README.md
# Snapsnap
Capture, cache, and replay HTTP queries in your tests using [Nock](https://github.com/nock/nock).
[](https://coveralls.io/github/salieri/snapsnap?branch=master)
[](https://codecov.io/gh/salieri/snapsnap)
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[](https://codeclimate.com/github/salieri/snapsnap/maintainability)
1. On the first run, the tests make real HTTP queries.
2. The queries and the responses are stored in `__http__/`.
3. On subsequent runs, cached responses are loaded from `__http__/` and used instead of real queries.
4. This is super helpful if your tests run in an environment that has no internet access, or you wish to maintain a snapshot of the responses.
## Usage
Snapsnap behaves similarly to Jest Snapshots. If an HTTP query has not been snapshotted, a real HTTP query will be made. Otherwise, a cached version of the query will be returned.
To signal that a test should be snapshotted, simply use `it.snap()` instead of `it()`. The framework will manage the rest.
```js
it.snap(
'should query the API',
async () => {
const result = await request('https://postman-echo.com/get?foo1=bar1&foo2=bar2');
const json = await result.json();
expect(json).toMatchSnapshot();
}
);
```
## Setting Up
### Jest
Supports Jest with [Circus](https://www.npmjs.com/package/jest-circus) (=default) test runner.
#### Configuring Jest
Snapsnap is implemented as a [test environment](https://jestjs.io/docs/configuration#testenvironment-string) that extends Jest's built-in `NodeEnvironment`.
```js
// ./jest.config.js
module.exports = {
testEnvironment: 'snapsnap/jest-env.js'
};
```
## Acknowledgments
Based on [Jest Nock Back](https://github.com/jonjaques/jest-nock-back) and [Jest Nock](https://github.com/spring-media/jest-nock).