The purpose of the server is to collect the events regarding each meeting rooms calendars.

After booting, the server picks-up from the provider API, the daily events for each meeting rooms defined into the events_config.json file, and subscribe to push notifications in order to be updated if any modification occures (adding, updating and cancellation). Afterwards, events are dispatched to the display devices which are kept up-to-date each time a push notification occures.

Meeting rooms’ display devices automatically subscribe to the server at their own boot time. IP addresses are automatically added to the events-config.json file, after their registration occuring at boot time.

The server is the only local entry point for the meeting rooms’ calendars events. It can run on a display device or on a dedicated one.
Because it has to subscribe to the provider push notifications’ API, it must provides a valid SSL certificat in order to allow https requests (supports only PEM files format).

Prerequisiter are as follow:

Open config.json file 

• event_provider: “google” or “microsoft” depending on the provider.
• impersonate_user_email: email adress of an admin to perform some API operations;
• logs-path: full path to the logs file.
• log_level: level of the logs as defined into winston package.
• event_config_path: full path to the meeting room config file…see below
• ssl_key_path: full path to SSL certificat key.PEM file.
• ssl_cert_path:  full path to SSL certificat cert.PEM file. 

• tcp_devices_port: port listen by display devices.
• tcp_devices_token: display devices Bearer Token (user defined).
• tcp_server_port: port listen by the server for display devices requests.
• tcp_server_token: server Bearer Token (user defined).

Open config.json file 

and fill-out the settings, e.g.:

• meeting_room_name: not used. Only to facilitate reading & identification .
• meeting_room_id: ID of the meeting room used by the server and displays devices (user defined).
• Calendar_id: email address of the meeting calendar (provider side).
• client: Registering list of the display devices having subscribing to the meeting room. You do not have to fill-out this array. It will be automaticaly updated by the display devices themselves at boot time. But you can manually unregister a device by just removing the json record into the array.

Subscriptions to the provider’s push notifications and display devices registration perform an automatic update of the file, looking like as above. Multiple display devices can subscribe to receive the event of a meeting room (why not! – let’s imagine other categories of devices). the push_channel_notification_id key is automatically filled by the server for a technical purpose only (you must not delete of change the key and the value). 

1) Install PM2 as describedhere

2) Create and start a new process.

3) Save current PM2 process (required for auto-run at boot time)

Restart process

In order to avoid any disruption caused by memory leaks or unexpectable dysfunction (let’s talk about bugs !), I strongly recommand to automatically restart the server app every day during night. This can be perform by adding a cronjob. Then, open the crontab:

and add following similar line (e.g. restart server app every day at 4AM)

A tiny API is provided in order to perform some technical operations. I recommend using postman.
The API can be address from http://server-ip-adress:tcp_server_port. Don’t forget to add the Bearer Token as defined into the config.json file (tcp_server_token).

Details are commented into the CMain.ts file (check sources).

This step is mandatory only if you have expected to update the source files (bug fixing, improvement, etc.). It requires typescript commands (see how to install here).

Again, Raspberry Zero W is definitly not the right device to manage development operations, as typescript compilation which requires processor and memory resources. I rather recommand to use a Raspberry pi B+.

1) Move to home directory

and copy source files from Github with Subversion

then, rename /src folder file and install dependancies as described above.

2) compile project in order to initialize /dist folder. Move to the source folder and run tsc command:

3) eventually, create and set config.json and events_config.json files as described above. these files must be placed into the new /dist folder.