lti-CloudTime

CloudTime (a word mixed between cloud and runtime) lets you easily set up and distribute Amazon EC2 virtual machines. It is a simple and very customized view of an associated Amazon AWS account. It is specially designed for teachers that want to offer cloud infrastructure to their students (i.e. computer programming, engineering and other subjects that need computing).

The LTI CloudTime integration lets teachers to create, start, shutdown an see the virtual machines and assign them to the students over the course. It also lets students to start and shutdown their assigned machines and know how to access to them.

Requirements

• PHP 5.X

• MySQL 5.X

• Amazon AWS Account

Step-by-Step Guide

Create a MySQL database

Execute the SQL file install/CloudTime.sql

Configure the file src/config.inc.php

Database configuration

define('BD_HOST', 'localhost');
define('BD_NAME', 'your db name');
define('BD_USERNAME', 'your db username');
define('BD_PASSWORD', 'your db password');

Folder to store file pems and distribute to students, the server should be able to write it but it shouldn't have http acces

define('PEM_PROTECTED_FOLDER', '/path/to/folder/');

Amazon Web Services Key. Found in the AWS Security Credentials.

define('AWS_KEY', '');

Amazon Web Services Secret Key. Found in the AWS Security Credentials

define('AWS_SECRET_KEY', '');

Amazon Account ID without dashes. Used for identification with Amazon EC2. Found in the AWS Security Credentials.

define('AWS_ACCOUNT_ID', '');

Configure the LTI credentials

File src/lib/IMSBasicLTI/configuration/authorizedConsumersKey.cfg p.e: in order to set as a consumer key "external", you have to put the following in the configuration file:

consumer_key.external.enabled=1 
consumer_key.external.secret=pwd_12345

LTI Launch to index.php of application

http://localhost/CloudTime/index.php

You can add a custom parameter allowing you to explicitly sets the region for the service to use. The custom parameter name is aws_region and possibles values are:

Region	Endpoint	Protocol
US East (Northern Virginia) Region default	ec2.us-east-1.amazonaws.com	HTTP and HTTPS
US West (Oregon) Region	ec2.us-west-2.amazonaws.com	HTTP and HTTPS
US West (Northern California) Region	ec2.us-west-1.amazonaws.com	HTTP and HTTPS
EU (Ireland) Region	ec2.eu-west-1.amazonaws.com	HTTP and HTTPS
Asia Pacific (Singapore) Region	ec2.ap-southeast-1.amazonaws.com	HTTP and HTTPS
Asia Pacific (Sydney) Region	ec2.ap-southeast-2.amazonaws.com	HTTP and HTTPS
Asia Pacific (Tokyo) Region	ec2.ap-northeast-1.amazonaws.com	HTTP and HTTPS
South America (Sao Paulo) Region	ec2.sa-east-1.amazonaws.com	HTTP and HTTPS

If not setted the custom parameter default value is US East (Northern Virginia) Region

Find updated values from here

Cron

You can enable a cron to stop the instances automatically (current is setted a 8 hours but you can change it).

You have to enable a cron:

*/5 * * * * wget -O /dev/null http://localhost/lti-CloudTime/stopInstancesCron.php