Relay transmits POST messages from server throught websockets (socket.io actually) to clients and websockets messages throught POST back to server.
On the client side, it is a common problem of keeping data up-to-date. Sometimes, implementing websokets might be inconvenient due to technological stack or the lack of experience. With Relay you can send data from server to client with a familiar HTTP POST request.
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Install Relay
git clone https://github.com/ivanrussu/relay cd ./relay npm install cp config.example.js config.js npm run serve -
Prepare a webhook. Webhook is used to control subscriptions and getting information from Relay. Webhooks are called as form-data POST requests and contain
api_key,eventanddatafields.eventfield determines the type of a webhook. It might beconnectedwhich contains no data and triggers every time a client connects to your link (you will get your link in the next step). When a client is trying to subscribe to a channelsubscribeevent triggers, in this casedatacontains array of strings inchannelsfield and any object inpayload. For example, you can usepayloadto authenticate clients. The last type of webhooks isrequestwith any object asdata. It is called when a client makes a request to your server. -
Create an API Key. API Key is used to authenticate requests between your server and Relay. To create one, use command
npm run make api-key. Answer questions and you will obtain API key as well as the link. Keep the key safe. Share the link with frontend. -
Send a message. Once the clients are ready to receive messages, simply make POST request like
curl --location --request POST 'https://relay.example.com/api/v1/broadcast' \ --header 'Content-Type: application/json' \ --data-raw '{ "api_key": "YOUR_API_KEY", "channel": "notifications", "data": { "event": "new_message", "user_id": 700695, "message": "Hello, how are you?" } }'