Use a custom webpack loader to avoid uncaught exceptions from JSONStream

JSONStream is a hybrid executable-library that doesn't get along well with webpack: it tries to run its binary code
which can throw uncaught exceptions. So we use a custom loader for it - which replaces remove-hashbang-loader, as it only
affected JSONStream too.

(I tried replacing JSONStream altogether, but turns out dockerode uses it too)

Change-Type: patch
Signed-off-by: Pablo Carranza Velez <pablo@resin.io>

Dockerfile

@@ -143,7 +143,7 @@ COPY package.json /usr/src/app/
 RUN JOBS=MAX npm install --production --no-optional --unsafe-perm \
 	&& npm dedupe
 
-COPY webpack.config.js remove-hashbang-loader.js /usr/src/app/
+COPY webpack.config.js fix-jsonstream.js /usr/src/app/
 COPY src /usr/src/app/src
 
 # Install devDependencies, build the coffeescript and then prune the deps

fix-jsonstream.js

@@ -0,0 +1,9 @@
+// JSONStream is a hybrid executable-library
+// and has a #! /usr/bin/env node at the beginning of the file.
+// This webpack loader removes it so that we have valid javascript for webpack to load.
+// Also, JSONStream starts a pipe between stdin and stdout if module.parent is undefined.
+// This pipe can fail throwing an uncaught exception, so we fake a module.parent to prevent this.
+// See https://github.com/dominictarr/JSONStream/issues/129
+module.exports = function (source) {
+  return "module.parent = {};\n" + source.toString().replace(/^#! .*\n/, '')
+}

remove-hashbang-loader.js

@@ -1,6 +0,0 @@
-// Some of the dependencies (e.g. JSONStream) are hybrid executable-library
-// and have a #! /usr/bin/env node at the beginning of the file.
-// This webpack loader removes it so that we have valid javascript for webpack to load.
-module.exports = function (source) {
-  return source.toString().replace(/^#! .*\n/, '')
-}

webpack.config.js

@@ -62,8 +62,8 @@ module.exports = {
 	module: {
 		rules: [
 			{
-				test: /\.js$/,
-				use: require.resolve('./remove-hashbang-loader')
+				test: /JSONStream\/index\.js$/,
+				use: require.resolve('./fix-jsonstream')
 			},
 			{
 				test: /\.coffee$/,