fix: implement fetch per spec

.github/workflows/nodejs.yml

@@ -20,25 +20,33 @@ jobs:
     - uses: actions/checkout@v2
 
     - name: Use Node.js ${{ matrix.node-version }}
-      uses: actions/setup-node@v1
+      uses: actions/setup-node@v2
       with:
         node-version: ${{ matrix.node-version }}
 
     - name: Install
       run: |
         npm install
 
-    - name: Unit test (no coverage)
+    - name: Test Tap
       run: |
-        npm test
+        npm run test:tap
 
-    - name: Unit test (coverage)
+    - name: Test Jest
       run: |
-        npm run coverage:ci
+        npm run test:jest
+
+    - name: Test node-fetch
+      run: |
+        npm run test:node-fetch
 
-    - name: Test types
+    - name: Test Types
       run: |
         npm run test:typescript
 
-    - name: Coverage report
+    - name: Coverage
+      run: |
+        npm run coverage:ci
+
+    - name: Coverage Report
       uses: codecov/codecov-action@v1

README.md

@@ -155,55 +155,19 @@ Calls `options.dispatch.connect(options)`.
 
 See [Dispatcher.connect](docs/api/Dispatcher.md#dispatcherconnect) for more details.
 
-https://fetch.spec.whatwg.org/
-
-### `undici.fetch([url, options]): Promise`
+### `undici.fetch(input[, init]): Promise`
 
 Implements [fetch](https://fetch.spec.whatwg.org/).
 
+https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/fetch
+https://fetch.spec.whatwg.org/#fetch-method
+
 Only supported on Node 16+.
 
 This is [experimental](https://nodejs.org/api/documentation.html#documentation_stability_index) and is not yet fully compliant the Fetch Standard. We plan to ship breaking changes to this feature until it is out of experimental.
 
-Arguments:
-
-* **url** `string | URL | object`
-* **options** `RequestInit`
-
 Returns: `Promise<Response>`
 
-#### Parameter: `RequestInit`
-
-https://fetch.spec.whatwg.org/#request-class
-
-* **method** `string`
-* **headers** `HeadersInit`
-* **body** `BodyInit?`
-* **referrer** *not supported*
-* **referrerPolicy** *not supported*
-* **mode** *not supported*
-* **credentials** *not supported*
-* **cache** *not supported*
-* **redirect** `RequestRedirect`
-* **integrity** *not supported*
-* **keepalive** *not supported*
-* **signal** `AbortSignal?`
-* **window** `null`
-
-#### Parameter: `Response`
-
-https://fetch.spec.whatwg.org/#response-class
-
-* **type** `ResponseType`
-* **url** `string`
-* **redirected** `boolean`
-* **status** `number`
-* **ok** `boolean`
-* **statusText** `string`
-* **headers** `Headers`
-
-See [Dispatcher.fetch](docs/api/Dispatcher.md#dispatcherfetchoptions-callback) for more details.
-
 ### `undici.upgrade([url, options]): Promise`
 
 Upgrade to a different protocol. See [MDN - HTTP - Protocol upgrade mechanism](https://developer.mozilla.org/en-US/docs/Web/HTTP/Protocol_upgrade_mechanism) for more details.

docs/api/Dispatcher.md

@@ -305,14 +305,6 @@ client.dispatch({
 })
 ```
 
-### `Dispatcher.fetch(options)`
-
-Implements [fetch](https://fetch.spec.whatwg.org/).
-
-Only supported on Node 16+.
-
-This is [experimental](https://nodejs.org/api/documentation.html#documentation_stability_index) and is not yet fully compliant the Fetch Standard. We plan to ship breaking changes to this feature until it is out of experimental.
-
 ### `Dispatcher.pipeline(options, handler)`
 
 For easy use with [stream.pipeline](https://nodejs.org/api/stream.html#stream_stream_pipeline_source_transforms_destination_callback). The `handler` argument should return a `Readable` from which the result will be read. Usually it should just return the `body` argument unless some kind of transformation needs to be performed based on e.g. `headers` or `statusCode`. The `handler` should validate the response and save any required state. If there is an error, it should be thrown. The function returns a `Duplex` which writes to the request and reads from the response.

index.js

@@ -14,6 +14,8 @@ const MockAgent = require('./lib/mock/mock-agent')
 const MockPool = require('./lib/mock/mock-pool')
 const mockErrors = require('./lib/mock/mock-errors')
 
+const nodeMajor = Number(process.versions.node.split('.')[0])
+
 Object.assign(Dispatcher.prototype, api)
 
 module.exports.Dispatcher = Dispatcher
@@ -84,7 +86,17 @@ function makeDispatcher (fn) {
 module.exports.setGlobalDispatcher = setGlobalDispatcher
 module.exports.getGlobalDispatcher = getGlobalDispatcher
 
-module.exports.fetch = makeDispatcher(api.fetch)
+if (nodeMajor >= 16) {
+  const fetchImpl = require('./lib/fetch')
+  module.exports.fetch = async function fetch (resource, init) {
+    const dispatcher = getGlobalDispatcher()
+    return fetchImpl.call(dispatcher, resource, init)
+  }
+  module.exports.Headers = require('./lib/fetch/headers').Headers
+  module.exports.Response = require('./lib/fetch/response').Response
+  module.exports.Request = require('./lib/fetch/request').Request
+}
+
 module.exports.request = makeDispatcher(api.request)
 module.exports.stream = makeDispatcher(api.stream)
 module.exports.pipeline = makeDispatcher(api.pipeline)