THM Digital Classroom

An application allowing student groups to arbitrarily create and join to Big Blue Button conferences. Students are able to create tickets to ask instructors for help, which may then join at the click of a button. Implements parts of the BBB-API to allow for easy deployment in an existing BBB environment.

Current functionality

Create classrooms and join via BBB API. It is possible to configure the feedback system (or any BBB Gateway, like Greenlight or PILOS) to connect to the digital classroom instead of a BBB cluster. Use the classrooms (default: http://localhost:8085) as BBB server address.

How to build

Property Values

Set properties in src/main/resources/application.properties. All relevant properties may be set via an environment variable.

Table 1. Custom property values

Namespace	Property	Env. Variable	Meaning
upstream.bbb	service-url	CLASSROOM_BBB_UPSTREAM_URL	The base URL of the BBB server to create conferences with.
	shared-secret	CLASSROOM_BBB_UPSTREAM_SECRET	Shared secret token to compute a checksum of requests against the BBB servers API with. See: BBB API Specification
classroom	host	CLASSROOM_HOST	Base URL (including the port if not default protocol port), at which the Digital Classroom application is contacted by users. Default: http://localhost:8085
	prefix-path	CLASSROOM_PREFIX_PATH	URI Path added by a proxy or similar applications to contact the digital-classroom from the internet. Default: "" (empty string)
	shared-secret	CLASSROOM_SECRET	Shared secret token a checksum of any request against the classrooms BBB-like API is computed with. Semantics as specified by BBB API linked above.
server	port	CLASSROOM_PORT	Server port at which this application will listen to HTTP requests Default: 8085
server.ssl	enabled	CLASSROOM_SSL_ENABLED	Whether to enable SSL encryption. Default: true
	key-store	CLASSROOM_KEYSTORE_PATH	Path to the key store that holds the SSL certificate Default: classpath:keystore.p12
	key-store-password	CLASSROOM_KEYSTORE_PASS	Password used to access the key store. Default: passwd
	key-store-type	CLASSROOM_KEYSTORE_TYPE	Type of the key store. Default: PKCS12
jwt	secret	CLASSROOM_JWT_SECRET	The key JSON Web Tokens issued by the digital classroom are signed with.
	expiration	CLASSROOM_JWT_EXPIRATION	Number of seconds after which JWTs should expire. Default: 900 (15 minutes)

Jar Build & Deploy

The only requirement is a JDK with version 11 or later. The command ./gradlew build on Linux / MacOSX or .\gradlew.bat build on Windows will compile the Angular frontend and produce an executable .jar artifact in build/libs/. which can be started via java -jar digital-classroom-VERSION.jar.

Docker Build & Deploy

A Docker image of the application may be created via docker-compose build in the root directory of this repository. The docker container may be run with docker-compose up. Any environment variables specified in Property Values are propagated to the Docker container.