fix: use native fetch if available (#62)

If you are in the Electron Renderer process, native fetch is available but it's ignored because the renderer does not respect the browser field of package.json, so we end up with `node-fetch` that uses a browser polyfill of the node `http` module which is very slow on Electron.

Instead use native fetch if it's available or `node-fetch` if not, unless you're on the Electron Main process in which case use `electron-fetch` which uses the Electron `net` module which is faster than the node `http` module in that environment.

package.json

@@ -16,7 +16,8 @@
     "./src/text-decoder.js": "./src/text-decoder.browser.js",
     "./src/temp-dir.js": "./src/temp-dir.browser.js",
     "./src/path-join.js": "./src/path-join.browser.js",
-    "./test/files/glob-source.spec.js": false
+    "./test/files/glob-source.spec.js": false,
+    "@achingbrain/electron-fetch": false
   },
   "repository": "github:ipfs/js-ipfs-utils",
   "scripts": {
@@ -34,15 +35,18 @@
   "license": "MIT",
   "dependencies": {
     "abort-controller": "^3.0.0",
-    "any-signal": "^1.1.0",
+    "any-signal": "^2.1.0",
     "buffer": "^5.6.0",
+    "@achingbrain/electron-fetch": "^1.7.2",
     "err-code": "^2.0.0",
     "fs-extra": "^9.0.1",
     "is-electron": "^2.2.0",
     "iso-url": "^0.4.7",
     "it-glob": "0.0.8",
     "merge-options": "^2.0.0",
     "nanoid": "^3.1.3",
+    "native-abort-controller": "0.0.3",
+    "native-fetch": "^2.0.0",
     "node-fetch": "^2.6.0",
     "stream-to-it": "^0.2.0"
   },

src/fetch.js

@@ -0,0 +1,10 @@
+'use strict'
+
+const { isElectronMain } = require('./env')
+
+if (isElectronMain) {
+  module.exports = require('@achingbrain/electron-fetch')
+} else {
+  // use window.fetch if it is available, fall back to node-fetch if not
+  module.exports = require('native-fetch')
+}

src/http.js

@@ -1,16 +1,17 @@
 /* eslint-disable no-undef */
 'use strict'
 
-const fetch = require('node-fetch')
+const {
+  default: fetch,
+  Request,
+  Headers
+} = require('./fetch')
 const merge = require('merge-options').bind({ ignoreUndefined: true })
 const { URL, URLSearchParams } = require('iso-url')
 const TextDecoder = require('./text-decoder')
-const AbortController = require('abort-controller')
+const AbortController = require('native-abort-controller')
 const anySignal = require('any-signal')
 
-const Request = fetch.Request
-const Headers = fetch.Headers
-
 class TimeoutError extends Error {
   constructor () {
     super('Request timed out')

test/http.spec.js

@@ -5,7 +5,7 @@ const { expect } = require('aegir/utils/chai')
 const HTTP = require('../src/http')
 const toStream = require('it-to-stream')
 const delay = require('delay')
-const AbortController = require('abort-controller')
+const AbortController = require('native-abort-controller')
 const drain = require('it-drain')
 const all = require('it-all')
 const { isBrowser, isWebWorker } = require('../src/env')