Fix import style to workaround node < 10 and webpack issues. (node-fetch#544)

* fix import rule for stream PassThrough

* avoid named export for compatibility below node 10

* compress flag should not overwrite accept encoding header

* doc update

* 2.2.1

Author: bitinn

CHANGELOG.md

@@ -5,6 +5,12 @@ Changelog
 
 # 2.x release
 
+## v2.2.1
+
+- Fix: `compress` flag shouldn't overwrite existing `Accept-Encoding` header.
+- Fix: multiple `import` rules, where `PassThrough` etc. doesn't have a named export when using node <10 and `--exerimental-modules` flag.
+- Other: Better README.
+
 ## v2.2.0
 
 - Enhance: Support all `ArrayBuffer` view types

LIMITS.md

@@ -26,5 +26,7 @@ Known differences
 
 - If you are using `res.clone()` and writing an isomorphic app, note that stream on Node.js have a smaller internal buffer size (16Kb, aka `highWaterMark`) from client-side browsers (>1Mb, not consistent across browsers).
 
+- Because node.js stream doesn't expose a [*disturbed*](https://fetch.spec.whatwg.org/#concept-readablestream-disturbed) property like Stream spec, using a consumed stream for `new Response(body)` will not set `bodyUsed` flag correctly.
+
 [readable-stream]: https://nodejs.org/api/stream.html#stream_readable_streams
 [ERROR-HANDLING.md]: https://github.com/bitinn/node-fetch/blob/master/ERROR-HANDLING.md

README.md

@@ -183,8 +183,6 @@ fetch('https://assets-cdn.github.com/images/modules/logos_page/Octocat.png')
     });
 ```
 
-[TODO]: # (Somewhere i think we also should mention arrayBuffer also if you want to be cross-fetch compatible.)
-
 #### Buffer
 If you prefer to cache binary data in full, use buffer(). (NOTE: buffer() is a `node-fetch` only API)
 
@@ -265,8 +263,6 @@ Perform an HTTP(S) fetch.
 
 `url` should be an absolute url, such as `https://example.com/`. A path-relative URL (`/file/under/root`) or protocol-relative URL (`//can-be-http-or-https.com/`) will result in a rejected promise.
 
-[TODO]: # (It might be a good idea to reformat the options section into a table layout, like the headers section, instead of current code block.)
-
 <a id="fetch-options"></a>
 ### Options
 
@@ -285,23 +281,22 @@ The default values are shown after each option key.
     timeout: 0,         // req/res timeout in ms, it resets on redirect. 0 to disable (OS limit applies)
     compress: true,     // support gzip/deflate content encoding. false to disable
     size: 0,            // maximum response body size in bytes. 0 to disable
-    agent: null         // http(s).Agent instance, allows custom proxy, certificate etc.
+    agent: null         // http(s).Agent instance, allows custom proxy, certificate, dns lookup etc.
 }
 ```
 
 ##### Default Headers
 
 If no values are set, the following request headers will be sent automatically:
 
-[TODO]: # ("we always said content-length will be "automatically calculated, if possible" in the default header section, but we never explain what's the condition for it to be calculated, and that chunked transfer-encoding will be used when they are not calculated or supplied." - "Maybe also add Transfer-Encoding: chunked? That header is added by Node.js automatically if the input is a stream, I believe.")
-
-Header            | Value
------------------ | --------------------------------------------------------
-`Accept-Encoding` | `gzip,deflate` _(when `options.compress === true`)_
-`Accept`          | `*/*`
-`Connection`      | `close` _(when no `options.agent` is present)_
-`Content-Length`  | _(automatically calculated, if possible)_
-`User-Agent`      | `node-fetch/1.0 (+https://github.com/bitinn/node-fetch)`
+Header              | Value
+------------------- | --------------------------------------------------------
+`Accept-Encoding`   | `gzip,deflate` _(when `options.compress === true`)_
+`Accept`            | `*/*`
+`Connection`        | `close` _(when no `options.agent` is present)_
+`Content-Length`    | _(automatically calculated, if possible)_
+`Transfer-Encoding` | `chunked` _(when `req.body` is a stream)_
+`User-Agent`        | `node-fetch/1.0 (+https://github.com/bitinn/node-fetch)`
 
 <a id="class-request"></a>
 ### Class: Request
@@ -451,8 +446,6 @@ Consume the body and return a promise that will resolve to one of these formats.
 
 Consume the body and return a promise that will resolve to a Buffer.
 
-[TODO]: # (textConverted API should mention an optional dependency on encoding, which users need to install by themselves, and this is done purely for backward compatibility with 1.x release.)
-
 #### body.textConverted()
 
 <small>*(node-fetch extension)*</small>
@@ -461,6 +454,8 @@ Consume the body and return a promise that will resolve to a Buffer.
 
 Identical to `body.text()`, except instead of always converting to UTF-8, encoding sniffing will be performed and text converted to UTF-8, if possible.
 
+(This API requires an optional dependency on npm package [encoding](https://www.npmjs.com/package/encoding), which you need to install manually. `webpack` users may see [a warning message](https://github.com/bitinn/node-fetch/issues/412#issuecomment-379007792) due to this optional dependency.)
+
 <a id="class-fetcherror"></a>
 ### Class: FetchError
 

package.json

@@ -1,6 +1,6 @@
 {
   "name": "node-fetch",
-  "version": "2.2.0",
+  "version": "2.2.1",
   "description": "A light-weight module that brings window.fetch to node.js",
   "main": "lib/index",
   "browser": "./browser.js",

src/body.js

@@ -5,7 +5,8 @@
  * Body interface provides common methods for Request and Response
  */
 
-import Stream, { PassThrough } from 'stream';
+import Stream from 'stream';
+
 import Blob, { BUFFER } from './blob.js';
 import FetchError from './fetch-error.js';
 
@@ -14,6 +15,9 @@ try { convert = require('encoding').convert; } catch(e) {}
 
 const INTERNALS = Symbol('Body internals');
 
+// fix an issue where "PassThrough" isn't a named export for node <10
+const PassThrough = Stream.PassThrough;
+
 /**
  * Body mixin
  *

src/index.js

@@ -7,18 +7,22 @@
  * All spec algorithm step numbers are based on https://fetch.spec.whatwg.org/commit-snapshots/ae716822cb3a61843226cd090eefc6589446c1d2/.
  */
 
-import { resolve as resolve_url } from 'url';
+import Url from 'url';
 import http from 'http';
 import https from 'https';
 import zlib from 'zlib';
-import { PassThrough } from 'stream';
+import Stream from 'stream';
 
 import Body, { writeToStream, getTotalBytes } from './body';
 import Response from './response';
 import Headers, { createHeadersLenient } from './headers';
 import Request, { getNodeRequestOptions } from './request';
 import FetchError from './fetch-error';
 
+// fix an issue where "PassThrough", "resolve" aren't a named export for node <10
+const PassThrough = Stream.PassThrough;
+const resolve_url = Url.resolve;
+
 /**
  * Fetch function
  *

src/request.js

@@ -7,12 +7,17 @@
  * All spec algorithm step numbers are based on https://fetch.spec.whatwg.org/commit-snapshots/ae716822cb3a61843226cd090eefc6589446c1d2/.
  */
 
-import { format as format_url, parse as parse_url } from 'url';
+import Url from 'url';
+
 import Headers, { exportNodeCompatibleHeaders } from './headers.js';
 import Body, { clone, extractContentType, getTotalBytes } from './body';
 
 const INTERNALS = Symbol('Request internals');
 
+// fix an issue where "format", "parse" aren't a named export for node <10
+const parse_url = Url.parse;
+const format_url = Url.format;
+
 /**
  * Check if a value is an instance of Request.
  *
@@ -187,9 +192,10 @@ export function getNodeRequestOptions(request) {
 	}
 
 	// HTTP-network-or-cache fetch step 2.15
-	if (request.compress) {
+	if (request.compress && !headers.has('Accept-Encoding')) {
 		headers.set('Accept-Encoding', 'gzip,deflate');
 	}
+
 	if (!headers.has('Connection') && !request.agent) {
 		headers.set('Connection', 'close');
 	}

src/response.js

@@ -5,12 +5,16 @@
  * Response class provides content decoding
  */
 
-import { STATUS_CODES } from 'http';
+import http from 'http';
+
 import Headers from './headers.js';
 import Body, { clone } from './body';
 
 const INTERNALS = Symbol('Response internals');
 
+// fix an issue where "STATUS_CODES" aren't a named export for node <10
+const STATUS_CODES = http.STATUS_CODES;
+
 /**
  * Response class
  *

test/test.js

@@ -731,6 +731,19 @@ describe('node-fetch', () => {
 		});
 	});
 
+	it('should not overwrite existing accept-encoding header when auto decompression is true', function() {
+		const url = `${base}inspect`;
+		const opts = {
+			compress: true,
+			headers: {
+				'Accept-Encoding': 'gzip'
+			}
+		};
+		return fetch(url, opts).then(res => res.json()).then(res => {
+			expect(res.headers['accept-encoding']).to.equal('gzip');
+		});
+	});
+
 	it('should allow custom timeout', function() {
 		this.timeout(500);
 		const url = `${base}timeout`;
@@ -782,7 +795,7 @@ describe('node-fetch', () => {
 
 	it('should set default User-Agent', function () {
 		const url = `${base}inspect`;
-		fetch(url).then(res => res.json()).then(res => {
+		return fetch(url).then(res => res.json()).then(res => {
 			expect(res.headers['user-agent']).to.startWith('node-fetch/');
 		});
 	});
@@ -794,7 +807,7 @@ describe('node-fetch', () => {
 				'user-agent': 'faked'
 			}
 		};
-		fetch(url, opts).then(res => res.json()).then(res => {
+		return fetch(url, opts).then(res => res.json()).then(res => {
 			expect(res.headers['user-agent']).to.equal('faked');
 		});
 	});
@@ -813,7 +826,7 @@ describe('node-fetch', () => {
 				'accept': 'application/json'
 			}
 		};
-		fetch(url, opts).then(res => res.json()).then(res => {
+		return fetch(url, opts).then(res => res.json()).then(res => {
 			expect(res.headers.accept).to.equal('application/json');
 		});
 	});