WIP on shimming streams in firefox

app/ece.js

@@ -1,4 +1,12 @@
-require('buffer');
+import 'buffer';
+import TransformStream from './transformStream';
+import { ReadableStream as ReadableStreamPony } from 'web-streams-ponyfill';
+try {
+  new ReadableStream().pipeThrough(new TransformStream());
+} catch (e) {
+  // eslint-disable-next-line no-global-assign
+  ReadableStream = ReadableStreamPony;
+}
 
 const NONCE_LENGTH = 12;
 const TAG_LENGTH = 16;

app/serviceWorker.js

@@ -1,5 +1,6 @@
 import Keychain from './keychain';
 import { downloadStream } from './api';
+import TransformStream from './transformStream';
 
 let noSave = false;
 const map = new Map();
@@ -37,8 +38,8 @@ async function decryptStream(request) {
       'Content-Type': file.type,
       'Content-Length': file.size
     };
-
-    return new Response(decrypted, { headers });
+    const body = decrypted.local ? decrypted.nativeReadable : decrypted;
+    return new Response(body, { headers });
   } catch (e) {
     if (noSave) {
       return new Response(null, { status: e.message });

app/transformStream.js

@@ -0,0 +1,25 @@
+/* global TransformStream */
+import { createReadableStreamWrapper } from '@mattiasbuelens/web-streams-adapter';
+import { TransformStream as TransformStreamPony } from 'web-streams-ponyfill';
+
+const toNative = createReadableStreamWrapper(ReadableStream);
+
+class TransformStreamLocal {
+  constructor(transformer) {
+    this.stream = new TransformStreamPony(transformer);
+    this.local = true;
+  }
+  get nativeReadable() {
+    return toNative(this.stream.readable);
+  }
+  get readable() {
+    return this.stream.readable;
+  }
+  get writable() {
+    return this.stream.writable;
+  }
+}
+
+export default (typeof TransformStream === 'function'
+  ? TransformStream
+  : TransformStreamLocal);

package-lock.json

@@ -91,7 +91,8 @@
     "@mattiasbuelens/web-streams-adapter": {
       "version": "0.1.0-alpha.1",
       "resolved": "https://registry.npmjs.org/@mattiasbuelens/web-streams-adapter/-/web-streams-adapter-0.1.0-alpha.1.tgz",
-      "integrity": "sha512-8YK2ZY6CAgrzFGfW2uPyNDMYvh7OmWjrlbdP+GeHiMJhzPF3XwrQaHyLQ4IZqGTj8NW879ttfbcqbLqQxWvtsw=="
+      "integrity": "sha512-8YK2ZY6CAgrzFGfW2uPyNDMYvh7OmWjrlbdP+GeHiMJhzPF3XwrQaHyLQ4IZqGTj8NW879ttfbcqbLqQxWvtsw==",
+      "dev": true
     },
     "@mrmlnc/readdir-enhanced": {
       "version": "2.2.1",
@@ -16276,10 +16277,10 @@
         "minimalistic-assert": "1.0.1"
       }
     },
-    "web-streams-polyfill": {
-      "version": "1.3.2",
-      "resolved": "https://registry.npmjs.org/web-streams-polyfill/-/web-streams-polyfill-1.3.2.tgz",
-      "integrity": "sha1-NxkkXpCSgtk5Z4JfRLzVUOnAOZU=",
+    "web-streams-ponyfill": {
+      "version": "1.4.2",
+      "resolved": "https://registry.npmjs.org/web-streams-ponyfill/-/web-streams-ponyfill-1.4.2.tgz",
+      "integrity": "sha512-LCHW+fE2UBJ2vjhqJujqmoxh1ytEDEr0dPO3CabMdMDJPKmsaxzS90V1Ar6LtNE5VHLqxR4YMEj1i4lzMAccIA==",
       "dev": true
     },
     "webpack": {

package.json

@@ -57,6 +57,7 @@
   },
   "devDependencies": {
     "@dannycoates/webpack-dev-server": "^3.1.4",
+    "@mattiasbuelens/web-streams-adapter": "0.1.0-alpha.1",
     "asmcrypto.js": "^0.22.0",
     "babel-core": "^6.26.3",
     "babel-loader": "^7.1.4",
@@ -112,7 +113,7 @@
     "svgo-loader": "^2.1.0",
     "testpilot-ga": "^0.3.0",
     "val-loader": "^1.1.1",
-    "web-streams-polyfill": "^1.3.2",
+    "web-streams-ponyfill": "^1.4.2",
     "webpack": "^4.15.1",
     "webpack-cli": "^3.0.8",
     "webpack-dev-middleware": "^3.1.3",
@@ -120,7 +121,6 @@
     "webpack-unassert-loader": "^1.2.0"
   },
   "dependencies": {
-    "@mattiasbuelens/web-streams-adapter": "0.1.0-alpha.1",
     "aws-sdk": "^2.266.1",
     "babel-polyfill": "^6.26.0",
     "choo": "^6.12.1",