This add-on is operated by Expedited Security

Generate QR codes for use anywhere

Last updated July 28, 2023

Qrackajack is an add-on to generate QR codes for use anywhere.

QR codes offer a means of connecting the real world to the virtual. Embed URLs, phone numbers or addresses within them and QR code readers will launch the associated applications when scanned.

Our custom styling options let you integrate your QR code designs into almost any site or company color scheme.

Qrackajack exposes an API and has supported examples for Ruby, PHP, Python, Node and Java.

Provisioning the add-on

Qrackajack can be attached to a Heroku application via the CLI:

$ heroku addons:create qrackajack
-----> Adding qrackajack to sharp-mountain-4005... done, v18 (free)

Once Qrackajack has been added a QRACKAJACK_API_KEY config variable will contain your specific API key granting access to the newly provisioned Qrackajack instance. This can be confirmed using the heroku config:get command.

$ heroku config:get QRACKAJACK_API_KEY
Bl4XHVbdsf5GIXQbqTfXR5IrpuuXER2kaVc2zNnA

After installing Qrackajack your application should be modified to fully integrate with the add-on.

Local setup

Environment setup

After provisioning the add-on it’s necessary to locally replicate the config vars so your development environment can operate against the service.

Use the Heroku Local command-line tool to configure, run and manage process types specified in your app’s Procfile. Heroku Local reads configuration variables from a .env file. To view all of your app’s config vars, type heroku config. Use the following command for each value that you want to add to your .env file.

$ heroku config:get QRACKAJACK_API_KEY -s  >> .env

For more information, see the Heroku Local article.

Input Parameter Descriptions

All languages will follow this call structure for inputs.

Using with Ruby

Install the Qrackajack gem.

# In your Gemfile
gem 'qrackajack', git: 'https://github.com/mbuckbee/Qrackajack-Gem.git'

Making a Request

> require 'qrackajack'
=> true

# Note: the 'Controller' here is not a reference to Rails controllers
# but an internal structure, won't interfere with your Rails app and will
# work fine in a standalone ruby app or another framework

> q = Qrackajack::APIController.new
> data = q.lookup("http://www.expeditedssl.com","100","100","#000000","#ffffff")

# Writes the file to the local directory, 'data' is the qr code returned
> File.open("my-qr-code.png", 'w'){|f| f.write(data)}

Using with PHP

<?php

$ch = curl_init('https://qrackajack.expeditedaddons.com/?api_key=' . getenv('QRACKAJACK_API_KEY') . '&bg_color=%23ffffff&content=http%3A%2F%2Fexample.org&fg_color=%23000000&height=256&width=256');

$response = curl_exec($ch);
curl_close($ch);

var_dump($response);

Using with Python

import os
from urllib2 import Request, urlopen

request = Request('https://qrackajack.expeditedaddons.com/?api_key=' + os.environ['QRACKAJACK_API_KEY'] + '&bg_color=%23ffffff&content=http%3A%2F%2Fexample.org&fg_color=%23000000&height=256&width=256')

response_body = urlopen(request).read()
print response_body

Using with Node

var request = require('request');

request('https://qrackajack.expeditedaddons.com/?api_key=' + process.env.QRACKAJACK_API_KEY + '&bg_color=%23ffffff&content=http%3A%2F%2Fexample.org&fg_color=%23000000&height=256&width=256', function (error, response, body) {
  console.log('Status:', response.statusCode);
  console.log('Headers:', JSON.stringify(response.headers));
  console.log('Response:', body);
});

Using with Java

// Maven : Add these dependencies to your pom.xml (java6+)
// <dependency>
//     <groupId>org.glassfish.jersey.core</groupId>
//     <artifactId>jersey-client</artifactId>
//     <version>2.8</version>
// </dependency>
// <dependency>
//     <groupId>org.glassfish.jersey.media</groupId>
//     <artifactId>jersey-media-json-jackson</artifactId>
//     <version>2.8</version>
// </dependency>

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.MediaType;

Client client = ClientBuilder.newClient();
Response response = client.target('https://qrackajack.expeditedaddons.com/?api_key=' + System.getenv('QRACKAJACK_API_KEY') + '&bg_color=%23ffffff&content=http%3A%2F%2Fexample.org&fg_color=%23000000&height=256&width=256}')
  .request(MediaType.TEXT_PLAIN_TYPE)
  .get();

System.out.println("status: " + response.getStatus());
System.out.println("headers: " + response.getHeaders());
System.out.println("body:" + response.readEntity(String.class));

Dashboard

The Qrackajack dashboard allows you to monitor your API usage limits.

The dashboard can be accessed via the CLI:

$ heroku addons:open qrackajack
Opening qrackajack for sharp-mountain-4005

or by visiting the Heroku Dashboard and selecting the application in question. Select Qrackajack from the Add-ons menu.

Troubleshooting

As a sanity check it is sometimes useful to bypass your app stack and check the endpoint, your API Key and parameters directly.

Test with your browser

# Modify the following to use your actual API Key
https://qrackajack.expeditedaddons.com/?api_key=REPLACE_WITH_YOUR_QRACKAJACK_API_KEY&bg_color=%23ffffff&content=http%3A%2F%2Fexample.org&fg_color=%23000000&height=256&width=256

A successful call will return your requested data with a HTTP result code of 200 along with your data. We recommend the JSON Formatter extension as a useful tool.

Your API key can be found on your Qrackajack dashboard.

Migrating between plans

Use the heroku addons:upgrade command to migrate to a new plan.

$ heroku addons:upgrade qrackajack:newplan
-----> Upgrading qrackajack:newplan to sharp-mountain-4005... done, v18 ($49/mo)
       Your plan has been updated to: qrackajack:newplan

Removing the add-on

Qrackajack can be removed via the CLI.

$ heroku addons:destroy qrackajack
-----> Removing qrackajack from sharp-mountain-4005... done, v20 (free)

Support

All Qrackajack support and runtime issues should be submitted via one of the Heroku Support channels. Any non-support related issues or product feedback is welcome at support@expeditedaddons.com