shron

Serverless Chronometer

shron is an NPM package to measure execution times of methods (sync/async) in TypeScript files by decorators (@Shron) automatically without modifying method bodies.

It also allows you to report those collected performance metrics (ShronResult) to external systems (AWS CloudWatch, Elasticsearch, Prometheus, etc ...) through callbacks.

Installation

You can add shron package into your AWS Lambda function as NPM package:

npm install --save shron

Shron is based on TypeScript's experimental method decorator feature. So to be able to use Shron without warning during compilation, you need to enable experimentalDecorators option in your tsconfig or jsconfig file:

{
  "compilerOptions": {
    ...
    "experimentalDecorators": true,
    ...
  },
  ...
}

Usage

import { Shron, ShronResult } from 'shron';

class Person {

    constructor(
        private firstName: string,
        private lastName: string,
    ) {}

    @Shron()
    hi(): void {
        console.log(`Hello!`);
    }

    @Shron({
        cb: (result: ShronResult) => {
            console.log(`Executed ${result.name} in ${result.duration} ms`);
        }
    })
    whoAreYou(): void {
        console.log(`I am ${this.firstName}, ${this.lastName}`);
    }

    @Shron({
        async: true,
    })
    async comeHere(): Promise<void> {
        console.log(`I am coming ...`);
        await new Promise(r => setTimeout(r, 1000));
        console.log(`Here I am`);
    }

    @Shron({
        async: true,
        cb: (result: ShronResult) => {
            console.log(`Executed ${result.name} in ${result.duration} ms`);
        }
    })
    async sleep(): Promise<void> {
        console.log(`Sleeping ...`);
        await new Promise(r => setTimeout(r, 1500));
        console.log(`Just woke up`);
    }

}

export async function hello(event: any) {
    const person = new Person('Serkan', 'Ozal');

    person.hi();

    person.whoAreYou();

    await person.comeHere();

    await person.sleep();

    return {
        message: 'Hello world!',
        input: event,
    };
}

which prints the following output:

2022-05-22T09:15:26.353+03:00	START RequestId: cc321720-17b8-4619-b986-5fdc785bcfd0 Version: $LATEST
2022-05-22T09:15:26.356+03:00	2022-05-22T06:15:26.356Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO Hello!
2022-05-22T09:15:26.356+03:00	2022-05-22T06:15:26.356Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO {"type":"shron","region":"us-east-1","functionName":"shron-playground-dev-hello","functionVersion":"$LATEST","traceId":"Root=1-6289d4fe-09ebe097262cbf46535df690;Parent=4a9c0ed8258690a7;Sampled=0","name":"hi","startTime":1653200126355,"duration":0,"durationHighRes":0.548095}
2022-05-22T09:15:26.356+03:00	2022-05-22T06:15:26.356Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO I am Serkan, Ozal
2022-05-22T09:15:26.356+03:00	2022-05-22T06:15:26.356Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO Executed whoAreYou in 0 ms
2022-05-22T09:15:26.357+03:00	2022-05-22T06:15:26.357Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO I am coming ...
2022-05-22T09:15:27.359+03:00	2022-05-22T06:15:27.359Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO Here I am
2022-05-22T09:15:27.360+03:00	2022-05-22T06:15:27.359Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO {"type":"shron","region":"us-east-1","functionName":"shron-playground-dev-hello","functionVersion":"$LATEST","traceId":"Root=1-6289d4fe-09ebe097262cbf46535df690;Parent=4a9c0ed8258690a7;Sampled=0","name":"comeHere","startTime":1653200126357,"duration":1002,"durationHighRes":1002.726858}
2022-05-22T09:15:27.360+03:00	2022-05-22T06:15:27.360Z cc321720-17b8-4619-b986-5fdc785bcfd0 INFO Sleeping ...
2022-05-22T09:15:28.865+03:00	END RequestId: cc321720-17b8-4619-b986-5fdc785bcfd0
2022-05-22T09:15:28.865+03:00   REPORT RequestId: cc321720-17b8-4619-b986-5fdc785bcfd0	Duration: 2509.56 ms	Billed Duration: 2510 ms	Memory Size: 1024 MB	Max Memory Used: 56 MB	Init Duration: 162.87 ms	

Contributing

Everyone is very welcome to contribute to this repository. Feel free to raise issues or to submit Pull Requests.

License

Licensed under MIT License.