bebras-server-modules

Server-side modules to be used by bebras tasks.

Some bebras tasks, for instance alkindi-task-enigma have both a client side and a server side ; the server side will generate data for the instance of the task, and send to the client side some of that data, hints and grade the answers, without revealing the full data to the user. bebras-server-modules is the intermediate between the client and the server for these tasks ; it handles communication, authentication, data storage and other features for these tasks.

Installation

1. Install a recent version of node.js (tested with version 10 ; doesn't work with some older versions)
2. Create a MySQL database for bebras-server-modules
3. Create a .env configuration file using .env.example as template (check documentation below)
4. npm install
5. Install pm2 globally : npm install pm2 -g

Usage

You must first add task modules to bebras-server-modules (for instance, the server-modules from alkindi-task-enigma. You can do so with :

node command.js tasks:add TASK_ID TASK_PATH

with TASK_ID being an unique identifier for the task, and TASK_PATH the absolute path to the js file of the module.

You can then start the servers :

./pm2_start_all.sh

If you kept the default port, the endpoint you will need to make your client tasks point at will be http://your.server:3101/ ; note that bebras-server-modules doesn't offer any user interface.

Configuration

Base configuration is done in the .env file ; use .env.example as template.

• DEV_MODE : set true for dev purposes only. It will skip the verification of tokens, and allow to send an object as task argument instead of a token.
• DB_ variables : settings to connect to the MySQL database
• STORAGE : set to local to save files locally, s3 to save files on S3
• STORAGE_PATH : folder in which saved assets will be stored, if you use STORAGE=local
• S3_ variables : settings to access S3, if you use STORAGE=s3
• STORAGE_URL : URL to access assets stored
• TOKENS_SERVICE_URL : URL to access the tokens service of bebras-server-modules
• TASKS_GRADER_KEY_FILE : private key to sign tokens, the default demo one can be used for development purposes

Development

During development, you can use the following command to restart automatically the tasks endpoint of bebras-server-modules each time a file in the task module tasks/enigma/ is modified :

npx pm2 start --no-daemon --watch tasks/enigma/ server.js --name bsm-tasks --interpreter babel-node -- tasks -p=3101

Adapt the watched path to the task you're working on.

Commands

• Add task : node command.js tasks:add TASK_ID TASK_PATH
• Remove task : node command.js tasks:remove TASK_ID
• Show all tasks : node command.js tasks:list
• Clear all tasks : node command.js tasks:clear
• Clear expired data : node command.js data:clear
• Stop all servers : ./pm2_stop_all.sh