Add docker container for testing

Dockerfile

@@ -0,0 +1,27 @@
+FROM node:lts-stretch-slim
+
+# Install Ruby & Bourbon
+# Only required once to init project
+# RUN apk update && apk upgrade && apk --update add \
+#     ruby ruby-dev ruby-ffi ruby-irb ruby-rake ruby-io-console ruby-bigdecimal ruby-json ruby-bundler \
+#     libstdc++ tzdata bash ca-certificates \
+#     && echo 'gem: --no-document' > /etc/gemrc
+# RUN gem install bourbon
+
+RUN apt-get update && \
+    apt-get install -y chromium firefox-esr && \
+    rm -rf /var/lib/apt/
+
+# Install node packages
+RUN npm install -g grunt-cli
+
+# Environment vars
+ENV DOCKER="True"
+
+# Copy files
+RUN mkdir -p /passman
+WORKDIR /passman
+COPY . /passman
+
+# Install project dependencies
+RUN npm install

karma.conf.js

@@ -1,10 +1,14 @@
 // Karma configuration
 // Generated on Mon Oct 17 2016 15:46:52 GMT+0200 (CEST)
 var isTravis = (process.env.TRAVIS_BUILD_NUMBER) ? true : false;
+var isDocker = (process.env.DOCKER) ? true : false;
 var browsers = ['Firefox'];
 if(!isTravis){
     browsers = ['Chrome'];
 }
+if(isDocker){
+    browsers = ['Chromium_Docker', 'Firefox_Docker'];
+}
 module.exports = function (config) {
     config.set({
 
@@ -62,6 +66,16 @@ module.exports = function (config) {
         // start these browsers
         // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
         browsers: browsers,
+        customLaunchers: {
+            Chromium_Docker: {
+              base: 'Chromium',
+              flags: ['--headless', '--disable-gpu', '--remote-debugging-port=9222', '--no-sandbox']
+            },
+            Firefox_Docker: {
+                base: 'Firefox',
+                flags: ['--headless']
+              }
+          },
 
 
         // Continuous Integration mode