From 356136817eef452f0996f7caf30385abce94f200 Mon Sep 17 00:00:00 2001
From: Josh Stevens <joshstevens19@hotmail.co.uk>
Date: Wed, 16 Oct 2019 16:00:23 +0100
Subject: [PATCH] fix: patch the angular `browser.js` to allow `{crypto: true,
 stream: true}`

---
 packages/web3/angular-patch.js | 17 +++++++++++++++++
 packages/web3/package.json     |  3 ++-
 2 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 packages/web3/angular-patch.js

diff --git a/packages/web3/angular-patch.js b/packages/web3/angular-patch.js
new file mode 100644
index 00000000000..3a76568e4cd
--- /dev/null
+++ b/packages/web3/angular-patch.js
@@ -0,0 +1,17 @@
+const fs = require('fs');
+const f = '../../node_modules/@angular-devkit/build-angular/src/angular-cli-files/models/webpack-configs/browser.js';
+
+// This is because we have to replace the `node:false` in the `/angular-cli-files/models/webpack-configs/browser.js`
+// with `node: {crypto: true, stream: true}` to allow web3 to work with angular (as they enforce node: false.)
+// as explained here - https://github.com/ethereum/web3.js/issues/2260#issuecomment-458519127
+if (fs.existsSync(f)) {
+    fs.readFile(f, 'utf8', function(err, data) {
+        if (err) {
+            return console.log(err);
+        }
+        var result = data.replace(/node: false/g, 'node: {crypto: true, stream: true}');
+        fs.writeFile(f, result, 'utf8', function(err) {
+            if (err) return console.log(err);
+        });
+    });
+}
diff --git a/packages/web3/package.json b/packages/web3/package.json
index 59c75f0db7e..bdbe2e3520b 100644
--- a/packages/web3/package.json
+++ b/packages/web3/package.json
@@ -20,7 +20,8 @@
     "author": "ethereum.org",
     "types": "types/index.d.ts",
     "scripts": {
-        "dtslint": "dtslint types --onlyTestTsNext"
+        "dtslint": "dtslint types --onlyTestTsNext",
+        "postinstall": "node angular-patch.js"
     },
     "authors": [
         {