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Kuzzle Geofencing precision

I have created a geofencing area around the Ram Manohar Lohia Hospital in New Delhi by using geojson.io.

I added two point, one inside and the other one outside the hospital but very close to geofencing zone limit (~2m).

Then I use Kuzzle realtime engine to subscribe to notification about document entering or exiting the Hospital geofencing area.

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const CHARSET = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';

function uniqueId (size) {
  let id = '';

  for (let idx = size; idx--;) {
    id += CHARSET[(Math.random() * CHARSET.length | 0)];
  }

  return id;

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V8 Promise Benchmarks

EDIT: 2021-01-10
Fixed here: nodejs/node#34291

EDIT: 2020-07-10
Explanation here: nodejs/node#33384 (comment)

By benchmarking promises against different version of Node.js, I noticed a performance drop in traditional promises (then/catch) between Node.js 10 and Node.js 12.

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const contextStore = new Map(); 
contextStore.set('requestId', uuid()); 

asyncLocalStorage.run(contextStore, async () => {
  // entering asynchronous context
});

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const log = message => { 
  const requestId = asyncLocalStorage.getStore(); 
  
  if (requestId) { 
    console.log(`[${requestId}] ${message}`); 
  } 
  else { 
    console.log(message); 
  } 
};

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const { AsyncLocalStorage } = require('async_hooks'); 
const asyncLocalStorage = new AsyncLocalStorage(); 

app.get('/', (request, response) => { 
  const requestId = uuid(); 
  
  asyncLocalStorage.run(requestId, async () => { 
    // entering asynchronous context
    log('Start processing');
    await emailService.notify(request.body.emails);

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class EmailService { 
  constructor (log) { 
    this.log = log; 
  } 
  
  async notify (emails, requestId) { 
    for (const email of emails) { 
      this.log(`[${requestId}] Send email: ${email}`); 
      sendGrid.send(email); 
    } 

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const app = express(); 
const log = message => console.log(message); 

const emailService = new EmailService(logger); 

app.get('/', (request, response) => { 
  const requestId = uuid(); 
  log(`[${requestId}] Start processing`); 
  
  await emailService.notify(request.body.emails, requestId); 

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What is the overhead of AsyncLocalStorage?

Run the benchmark:

$ npm i benchmark

# Run the AsyncLocalStorage benchmark
$ node async-local-storage.js ASL
ASL x 15,551 ops/sec ±3.30% (79 runs sampled)

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# https://stackoverflow.com/questions/60910274/int32-vs-float64-performances-in-crystal
require "benchmark"

def percentage_diff(number_a, number_b)
  small_number = (number_a > number_b) ? number_b : number_a
  big_number = (number_a < number_b) ? number_b : number_a

  (big_number - small_number) / small_number
end