Create Analytics SDK

/*
This is a Swiggy frontend interview question.

Implement an analytics SDK that exposes log events, it takes in events and queues them, and then starts sending the events. The SDK should adhere the following properties.

• Send each event after a delay of 1 second and this logging fails every n % 5 times.
• Send the next event only after the previous one resolves.
• When the failure occurs attempt a retry.

Input:
const sdk = new SDK();

sdk.logEvent("event 1");
sdk.logEvent("event 2");
sdk.logEvent("event 3");
sdk.logEvent("event 4");
sdk.logEvent("event 5");
sdk.logEvent("event 6");
sdk.logEvent("event 7");
sdk.logEvent("event 8");
sdk.logEvent("event 9");
sdk.logEvent("event 10");

sdk.send();

Output:
"Analytics sent event 1"
"Analytics sent event 2"
"Analytics sent event 3"
"Analytics sent event 4"
"-----------------------"
"Failed to send event 5"
"Retrying sending event 5"
"-----------------------"
"Analytics sent event 5"
"Analytics sent event 6"
"Analytics sent event 7"
"Analytics sent event 8"
"-----------------------"
"Failed to send event 9"
"Retrying sending event 9"
"-----------------------"
"Analytics sent event 9"
"Analytics sent event 10"
*/

class SDK {
    constructor() {
        this.queue = [];
        this.count = 1;
    };

    logEvent(ev) {
        this.queue.push(ev);
    };

    wait = () => new Promise((resolve, reject) => {
        setTimeout(() => {
            if (this.count % 5 === 0) {
                reject();
            } else {
                resolve();
            }
        }, 1000);
    });

    sendAnalytics = async function () {
        if (this.queue.length === 0) {
            return;
        };

        const current = this.queue.shift();

        try {
            await this.wait();
            console.log("Analytics sent " + current);
            this.count++;
        } catch (e) {
            console.log("-----------------------");
            console.log("Failed to send " + current);
            console.log("Retrying sending " + current);
            console.log("-----------------------");
            this.count = 1;
            this.queue.unshift(current);
        } finally {
            this.sendAnalytics();
        }
    };

    send = async function () {
        this.sendAnalytics();
    };
};

const sdk = new SDK();

sdk.logEvent("event 1");
sdk.logEvent("event 2");
sdk.logEvent("event 3");
sdk.logEvent("event 4");
sdk.logEvent("event 5");
sdk.logEvent("event 6");
sdk.logEvent("event 7");
sdk.logEvent("event 8");
sdk.logEvent("event 9");
sdk.logEvent("event 10");
sdk.logEvent("event 11");
sdk.logEvent("event 12");
sdk.logEvent("event 13");
sdk.logEvent("event 14");
sdk.logEvent("event 15");
sdk.logEvent("event 16");
sdk.logEvent("event 17");
sdk.logEvent("event 18");
sdk.logEvent("event 19");
sdk.logEvent("event 20");

sdk.send();