NWO’s bleeding-edge technology enables clients to surface the fears, motivations, and demand drivers underlying various Signals, providing them with unprecedented access to the why behind a narrative

nwo.ai

Despite the evident advantages of automated testing in enhancing speed, precision, and cost-efficiency in specific scenarios, an intriguing statistic reveals that only . 5% of companies commit to fully automated testing In this article, we will unravel why manual testing remains an indispensable component of every project for the foreseeable future despite the relentless advancement of automated testing technologies. Manual Testing Manual testing forms the foundation for automation and is crucial in various scenarios: In situations where product functionality undergoes frequent changes, manual testing becomes pivotal. It offers the flexibility to swiftly adapt to changes without the burden of perpetually updating automated scripts. Rapidly Changing Functionality: Manual testing shines when dealing with intricate or ambiguous test scenarios, such as multi-tier user authentication processes. Manual testers excel in improvisation, navigating the application to uncover edge cases and modifying their test strategies. Complex for Automation or Undefined Test Scenarios: Manual testers provide critical insights into usability, design effectiveness, and overall user satisfaction, elements often missed by automated processes. UI/UX Testing: Automation may not be necessary on smaller projects where a few manual testers suffice. In such contexts, manual testing provides comprehensive coverage and is a more cost-effective and practical approach. Small-Scale Projects: Example: Evaluating a novel gesture-based interaction feature in a mobile app requires exclusively manual testing. This involves assessing the naturalness, responsiveness, and overall user satisfaction with these interactions, which automated tests cannot effectively measure. Testers manually execute gestures to navigate the app, evaluating the feature's intuitiveness and user experience firsthand. Automated Testing Automated testing excels in stable environments and for regression testing. It's ideal for scenarios where functionalities are consistent and manual testing might be limited due to high volume, complexity, or repetitive tasks. Automated tests can run independently, even overnight, providing quick, reliable results by the following day. This makes it a strategic choice for ensuring stability and efficiency in the testing process. Example: Automated testing is essential for stress testing a web application expected to handle high traffic, such as during a flash sale. It's impractical for manual testing to simulate the scale of simultaneous user activities that automated tools like JMeter can, ensuring the application's performance under peak load conditions. Comparative Analysis of Manual vs. Automated Testing Before delving into the central question of our article, let's examine the critical differences between automated and manual testing. This table summarizes the main distinctions between manual and automated testing, offering a quick overview of their strengths and challenges. The choice between them depends on project requirements, such as scale, complexity, and the need for immediate feedback. Most organizations opt for a hybrid approach, combining both methods to ensure comprehensive testing and high-quality software delivery. Why a Balanced Approach to Automated and Manual Testing Is Best for Projects Therefore, the most optimal approach for this project is the combination of manual and automated testing. Here’s why a balanced integration of automated and manual testing methodologies emerges as the best practice for projects: #1. The Base for Automation Manual testing serves as the bedrock upon which automated testing is built. Test cases and scenarios are validated manually to establish a baseline for expected behavior. These manual tests help identify critical features, user workflows, and potential areas of concern, which are then translated into automated test scripts. Without this initial manual testing phase, automating tests becomes a blind process lacking the human insights to detect early defects and vulnerabilities. __Manual __ test case example: Submit a «Contact Us» form with the valid data TITLE: STEPS: Navigate to the «Contact Us» page Enter the valid data Check the «Privacy Policy» checkbox Click the «Send Message» button The «Message is sent» success popup should be displayed EXPECTED RESULT: __Automation __ example (using Playwright and TypeScript): import { test } from '@playwright/test'; import ContactUsPage from '../pages/ContactUsPage'; const validFullName = 'Test Customer'; const validEmail = 'testemail@gmail.com'; const validMessage = 'It is interesting to learn about your services, get advice on my project and discuss the free trial in more detail.\nThank you!\nWaiting for feedback!'; test.describe('Contact Us form test', () => { test('Submit a «Contact Us» form with the valid data', async ({ page }) => { const contactUsPage = new ContactUsPage(page); // Navigate to the «Contact Us» page await contactUsPage.navigate(); // Enter the valid data await contactUsPage.enterFullName(validFullName); await contactUsPage.enterEmail(validEmail); await contactUsPage.enterMessage(validMessage); // Check the «Privacy Policy» checkbox await contactUsPage.clickPrivacyPolicyCheckbox(); // Click the «Send Message» button await contactUsPage.clickSendMessageButton(); // Verify success message is displayed await contactUsPage.isSuccessModalDisplayed(); }); }); #2. Accessibility Testing Ensuring that software is accessible to users with disabilities is a critical aspect of quality assurance. Manual testing allows testers to evaluate the application from the perspective of users with disabilities, including screen readers, keyboard navigation, and other assistive technologies. These aspects are challenging to automate fully, making manual testing essential to ensuring inclusivity and compliance with accessibility standards. consider a government website that provides essential information to citizens. Manual testing ensures that individuals with visual impairments can navigate the site using screen readers, access necessary forms, and receive critical updates. For instance, These functionalities are challenging to automate comprehensively due to the varied needs of users with disabilities, emphasizing the indispensability of manual accessibility testing in guaranteeing equal access to crucial information. #3. Risk Management By leveraging both testing methodologies, teams can ensure a more comprehensive risk assessment. Imagine a healthcare software project where manual testing is crucial for validating patient data input and ensuring the software's compliance with medical regulations. Automated testing complements this by verifying data integrity and the system's overall functionality. #4. Continuous Integration and Agile Environments Combining automated and manual testing in continuous integration (CI) and agile development environments ensures that quality keeps pace with development. For instance, consider a social media platform where automated tests verify core functionalities like user authentication, while manual testing focuses on user interface improvements and usability. #5. Comprehensive Bug Discovery Manual testing can uncover subtle, context-specific bugs that automated scripts may overlook. Testers can apply human intuition and creativity to explore the software from end-users perspectives, identifying issues that might not be covered in automated test cases. This aspect becomes crucial for ensuring a polished user experience, catching unexpected edge cases, and improving overall software quality. imagine testing an e-commerce website where an automated script checks the functionality of the "Add to Cart" button and appears to work flawlessly. However, during manual testing, a tester notices that when adding multiple items rapidly, the cart icon briefly flashes, potentially confusing users about the status of their selections. For instance, This nuanced issue, uncovered by human intuition and creativity, highlights the importance of manual testing in ensuring a user-friendly experience, improving overall software quality, and benefiting end-users. Сonclusions In conclusion, the ideal approach to software testing lies in a balanced integration of manual and automated testing methodologies. Manual testing, with its adaptability, user-centric insights, and ability to uncover nuanced issues, is the foundation upon which automation is built. Combining both approaches ensures comprehensive testing, high-quality software, and an improved user experience, making it the best practice for modern projects.

To Automate or Not: Navigating Manual and Automated Testing Paradigms

স্বয়ংক্রিয় বা না করা: ম্যানুয়াল এবং স্বয়ংক্রিয় পরীক্ষার দৃষ্টান্ত নেভিগেট করা

Automatisieren oder nicht: Navigieren in manuellen und automatisierten Testparadigmen

Automatizar o no: navegar por paradigmas de pruebas manuales y automatizadas

Automatiser ou non : naviguer dans les paradigmes de tests manuels et automatisés

स्वचालित करें या नहीं: मैनुअल और स्वचालित परीक्षण प्रतिमानों को नेविगेट करना

自動化するか否か: 手動テスト パラダイムと自動テスト パラダイムをナビゲートする

자동화 여부: 수동 및 자동 테스트 패러다임 탐색

Para Automatizar ou Não: Navegando nos Paradigmas de Testes Manuais e Automatizados

Автоматизировать или нет: ориентироваться в парадигмах ручного и автоматического тестирования

Otomatikleştirmek veya Otomatikleştirmemek: Manuel ve Otomatik Test Paradigmalarında Gezinme

Để tự động hóa hay không: Điều hướng các mô hình thử nghiệm thủ công và tự động

是否自动化：导航手动和自动测试范式

The Protestants

Node.js is a single-threaded event-driven platform that is capable of running non-blocking, asynchronous programming. These functionalities of Node.js make it memory efficient. The L allows Node.js to perform non-blocking I/O operations despite the fact that JavaScript is single-threaded. It is done by assigning operations to the operating system whenever and wherever possible. Event oop In this article, I will try to explain the mechanism of concurrency at Node.js which is the Event Loop. The first thing to consider is that Node.js is written in Javascript alone and in c++ and Javascript to operate correctly. There are many libraries upon which node depends, but the two foremost dependencies that handle most node.js operations and . V8 LIBUV These two dependencies allow us to write pure JavaScript code that runs in Node.js while still giving us access to the file reading functionality implemented in LIBUV. The event loop mechanism is also implemented in this library. Let’s open the source code of this library and see how the mechanism is implemented. Source code of written in for shown below (but you can also look for ): LIBUV C unix win int uv_run(uv_loop_t* loop, uv_run_mode mode) {
  int timeout;
  int r;
  int can_sleep;

  r = uv__loop_alive(loop);  // Check loop alive ----- (1)
  if (!r)
    uv__update_time(loop);

  while (r != 0 && loop->stop_flag == 0) {
    uv__update_time(loop);
    uv__run_timers(loop);   // Check timer phase ----- (2)

    can_sleep =
        QUEUE_EMPTY(&loop->pending_queue) && QUEUE_EMPTY(&loop->idle_handles);

    uv__run_pending(loop);  // Check pending callbacks ----- (3)
    uv__run_idle(loop);     // Check idle  ------ (4)
    uv__run_prepare(loop);  // Check prepare ----- (5)

    timeout = 0;
    if ((mode == UV_RUN_ONCE && can_sleep) || mode == UV_RUN_DEFAULT)
      timeout = uv__backend_timeout(loop);

    uv__metrics_inc_loop_count(loop);

    uv__io_poll(loop, timeout);  // Check poll ----- (6)

    for (r = 0; r < 8 && !QUEUE_EMPTY(&loop->pending_queue); r++)
      uv__run_pending(loop);

    uv__metrics_update_idle_time(loop);

    uv__run_check(loop);            // Check run checks ------ (7)
    uv__run_closing_handles(loop);  // Check close callbacks ------ (8)

    if (mode == UV_RUN_ONCE) {
      uv__update_time(loop);
      uv__run_timers(loop);
    }

    r = uv__loop_alive(loop);
    if (mode == UV_RUN_ONCE || mode == UV_RUN_NOWAIT)
      break;
  }

  return r;
} Let’s make a scheme of work on the diagram. The following diagram shows a simplified overview of the event loop’s order of operations. Consists of two parts and which are divided into (Each box will be referred to as a “phase” of the event loop). Microtasks Macrotasks phases Phases Overview this phase executes callbacks scheduled by and . Timers: setTimeout() setInterval() executes I/O callbacks deferred to the next loop iteration. Pending callbacks: only used internally. Idle, Prepare: retrieve new I/O events; execute I/O related callbacks (almost all with the exception of close callbacks, the ones scheduled by timers, and ); node will block here when appropriate. Poll: setImmediate() callbacks are invoked here. Check: setImmediate() some close callbacks, e.g. . Close callbacks: socket.on('close', ...) Each phase has a FIFO queue of callbacks to execute. When the event loop enters a given phase, it will perform any operations specific to that phase and then execute callbacks on that phase’s queue until either the queue is exhausted, or until the maximum number of callbacks is fulfilled. When the queue is exhausted or the callback limit is reached, the event loop will move to the next phase. Also this library is responsible for providing Nodejs with multithreading or the ability to provide a pool of threads in a Nodejs process for synchronous tasks to ride on. The thread pool consists of four threads(can configure it up to 128), created to handle heavy-duty tasks that shouldn’t be on the main thread. And with this set-up, our application is not blocked by these tasks. some APIs — — as listed below, use the thread pool created by libuv: dns.lookup() All zlib APIs that are synchronous All fs APIs that are synchronous except fs.FSWatcher() Asynchronous crypto APIs The above list can be further categorised into CPU-intensive operations and I/O-intensive operations. Let’s take a look at the following code and how it will be processed const fs = require('fs');
const http = require('http');

const requestListener = function (req, res) {
  res.writeHead(200);
  res.end('Hello, World!');
}

const server = http.createServer(requestListener);
server.listen(3000);

console.log("Start"); // ----- (A)

setTimeout(() => console.log("setTimeout -- 1"), 0); // ----- (B)

setImmediate(() => console.log("setImmediate")); // ----- (C)

fs.readFile(__filename, () => { // ----- (D)
    console.log("readFile callback"); // ----- (E)
    setTimeout(
      () => console.log("setTimeout in readFile"),
       0
    ); // ----- (F)
    setImmediate(
      () => console.log("setImmediate in readFile")
    ); // ----- (G)
    process.nextTick(
      () => console.log("nextTick in readFile")
    ); // ----- (H)
});

Promise.resolve().then(() => { // ----- (I)
  console.log("Promise success callback"); // ----- (J)
  process.nextTick(
    () => console.log("Promise nextTick")
  ); // ----- (K)
  setImmediate(
    () => console.log("Promise setImmediate")
  ); // ----- (L)
});

process.nextTick(() => console.log("nextTick")); // ----- (M)

setTimeout(() => console.log("setTimeout -- 2"), 0); // ----- (N)

console.log('End'); // ----- (O) So when Node.js is reading file, it executes synchronously consoles (A, O).the rest of the asynchronous operations will be divided into micro and macro tasks, after the execution of the synchronous code, our Event Loop starts working. The order of execution of asynchronous operations presented below: Conclusion The first thing to note is that your code in Nodejs is single-threaded. And this does not mean that Node is running on a single thread. The question ‘is Node single-threaded?’ is always confusing because Node runs on V8 and Libuv. By itself, V8 works one thread but with the help the Libuv library is using the event Loop, distribute operations into different queues (phases), and for some heavy operations(it is first sent to the thread pool for execution by different threads, then the raised ones return to the phase), after which the Event Loop, according to the underlying mechanism, starts sending callbacks for execution to the main thread. That's the whole concurrency mechanism in Node.js, which is called the Event Loop. Hope it was useful for you! Thanks for reading!

How the Event Loop Works in Node.js

Many IT companies have adopted the practice of on-duty duty. An engineer is on duty, and his duty lasts for a shift. Usually, the shift lasts one day or one week. There are cases of increasing or decreasing this period, but this is rare. The engineer's duties in this role vary from company to company, but there are some common points. You have to answer the questions that come into the team. It is necessary to monitor the performance of the services for which the team is responsible. To deal with fires and incidents. Escalate the incident further if you can't figure it out. We'll talk about how to be well-prepared for duty as an engineer in this article. Definition of perfect duty engineer If incidents or fires occur on your shift in a combat environment, it does not mean you are a terrible engineer. To be a good duty engineer, if problems occur, you need to solve them as quickly and cost-effectively as possible. A well-trained engineer understands where they can handle himself and where it's worth escalating the situation further. They should know when and whom to call for help. They must not allow, if possible, the same problems to be repeated. Experience It is helpful to take advantage of the experience of yourself and the team to better prepare for duty. It's a good idea to start by looking at what documentation already exists for handling incidents. Is there documentation at the company or team level? It is essential to know where it is and be familiar with it. If it doesn't exist, could you try to initiate the process of creating one? Then it is worth checking what incidents have already happened and how they are recorded in the knowledge store. Are there any postmortems and are there tasks to be fixed? Do you know if these tasks are being done? If tasks for fixing the situation are created, but not implemented, this is a reason to discuss this in a meeting with your manager. Do you know if the duties of the engineer on duty are recorded? What are they responsible for, and what is not? If there is no such documentation or understanding, it would be helpful for the whole team to have one. Tools The toolkit for the on-duty engineer is specific and somewhat different from the developer's everyday toolkit. The main tasks that arise during firefighting are those that cannot be solved by existing queries Let's look at these tools in more detail: The primary technical tool for the dutyman, with the help of which you can solve many problems, is bash. Often in fire mode, you need to perform some operations with the product database. The skill of working with the database via the terminal - psql for PostgreSQL or mongosh for MongoDB will help. These tools are given as examples, you can search for your own database. For many databases, there are visual tools to work with, but the terminal is available everywhere, requires minimal internet, and is very flexible. For fire mode, it can be very useful. https://www.postgresguide.com/utilities/psql/ https://www.mongodb.com/docs/mongodb-shell/ curl is a tool that will allow you to make a considerable number of queries, and when combined with knowledge of bash, you will become almost omnipotent. It will be very useful if you have a set of ready-made scripts at hand at the time of the fire. They should be as simple and straightforward as possible. Yes, you can probably write them very quickly, but when you have limited time, it's great to have a ready-made set that allows you to think only about the crash and not how to implement the same tying. The scripts below are just a representation of the potential structure of such scripts. Of course, your code should be tested before the incident and be as simple and straightforward as possible. It is helpful to have the following scripts: A script that generates a file from the data provided. These can be obtained from other commands or by making an independent request. An example of such a script in Python is shown below. import csv

def modify(filename):
    tmpFile = "tmp.csv"
    # Reading file with data and creation of output file
    with open(filename, "r") as file, open(tmpFile, "w") as outFile:
        # Create reader for initial file
        reader = csv.reader(file, delimiter=',')
        # Create writer for output file
        writer = csv.writer(outFile, delimiter=',')
        # Read header line
        header = next(reader)
        # Write header line
        writer.writerow(header)
        # Process initial file line by line
        for row in reader:
            colValues = []
            # Process each column of each line
            for col in row:
                # Let for example transform all columns to lowercase
                colValues.append(col.lower())
            # Write modified line to final file
            writer.writerow(colValues)

filename = 'sample_data.csv'
modify(filename) A script that will call the required endpoints with the specified parallelism. It doesn't have to be anything complicated. Below is an example of a simple JavaScript code that will generate a sh file with the specified parallelism that can help you with that. Yes, we don't have result handling here, but it's not always needed, and you can modify your toolkit with a result handling version if required. For example, we have a file that reads and writes the whole data, but you can create stream scripts for huge files. const fs = require('fs');

const initialFilePath = 'sample_data.csv';
const outputFilePath = 'sample_script.sh';

const amountOfParallelRequests = 5; // Remember about the throughput and the bandwidth of your services
const delimiterForCSV = ',';

// Read the initial file and split it by lines
// You could transform it to an object if it's relevant to your situation
let initialFile = fs.readFileSync(initialFilePath).toString().split('\n');

// Prepare boilerplate for sh script
let outputString = '#!/bin/bash\n\n';

// Write data with parallel execution
// Skip header for CSV
// The code for parallel requests was received from https://serverfault.com/questions/456490/execute-curl-requests-in-parallel-in-bash
// and you could implement your version instead
for (let i = 1; i < initialFile.length; i++){
    let line = initialFile[i];

    if (!line) {
        continue;
    }

    let processedLine  = line.split(delimiterForCSV); // We don't implement processing of errors here
    // Let's suggest that the necessary for request value lies in second column
    let desiredValue = processedLine[1];

    if (desiredValue === undefined) {
        console.error('We have a trouble ' + line);
    }

    outputString += `curl -s -o foo http://example.com/file${desiredValue} && echo "done with ${desiredValue}"  &\n`;

    if (i % amountOfParallelRequests === 0 || i === initialFile.length - 1) {
        outputString += '\nwait\n\n';
    }
}

fs.writeFileSync(outputFilePath, outputString);

// Indicate the success
console.log('Success'); A script that gets something from a database or service and puts the converted result back or maybe calls another endpoint. I suggest implementing it yourself, not forgetting about authorization and appropriate usage scenarios. Knowledge In addition to tools and experience, a certain amount of knowledge is helpful when you go on duty. I would like to know about the logs and metrics of your services. Where do they go and how do you get there? Would you happen to know how to use these tools? When you get a call at night from an on-call service that tells you that your service is down - it's in your best interest to quickly discover what's going wrong. To do that, you need to know precisely where your metrics and logs store and what to look at first. How to postpone alerts? After analyzing the incident, it often comes out that the current accident may be waiting for the morning, so it is good to understand how to postpone the alert. Not to close, because in the case of some operations you will be notified again, but precisely to postpone. You should remember to deal with and correct the situation or alert as soon as you start your typical work day. Where do the contacts lie or how do you get in touch with colleagues or members of other teams? There must be a clear tool or knowledge in your head - who understands/should know about the situation when it happened. The experts can help you solve the incident, and the stakeholders need to know that something is going wrong. You must have access to their contacts, ideally their phone, because many people turn off notifications from office chats outside of business hours. How do you get access to the production/database and increase access if access levels exist? If you don't have access, you need to know who to go to or what to do to get the access you want. How do you get the code into production quickly? Sometimes problems require a quick change in the service code in production. In general, this is rightly considered bad practice, but often in an emergency, this is not the case. Sometimes you don't want to wait for long E2E tests but need to quickly get the code into the production environment. I would like you to understand how to do this. What data is stored in the database? Are there any schemes of data movement within the product and between services?  If you need to interact with the database, it's good to know how the data is organized in a particular service, where it comes from, and who uses it. This will allow you to deal with problems, if there are any, sooner. In addition to tools and experience, a certain amount of knowledge is helpful when you go on duty. Conclusion Even in companies and teams with an excellent engineering culture, on-duty accidents and fires happen. To avoid this, the team must make every effort to improve current processes and products. Still, each engineer must also be prepared that an accident will happen and urgently have to deal with it. To do this, it is worth using all the accumulated personal and team experience. Knowing about the organization and services and being confident in your toolkit is worth knowing. Useful links https://zach-gollwitzer.medium.com/the-ultimate-bash-crash-course-cb598141ad03 https://www.youtube.com/watch?v=oxuRxtrO2Ag https://www.postgresguide.com/utilities/psql/ https://www.mongodb.com/docs/mongodb-shell/

What is a Perfect Duty Engineer?

Ingeniero de servicio perfecto

Ingénieur de service parfait

परफेक्ट ड्यूटी इंजीनियर

パーフェクト デューティ エンジニア

Engenheiro de serviço perfeito

Kỹ sư hoàn hảo

完美值班工程师

The Count of Monte Cristo,by Alexandre Dumas, père is part of HackerNoon’s Book Blog Post series. You can jump to any chapter in this book here: . Volume One, Chapter 25: The Unknown [LINK TO TABLE OF LINK] Chapter 25. The Unknown Day, for which Dantès had so eagerly and impatiently waited with open eyes, again dawned. With the first light Dantès resumed his search. Again he climbed the rocky height he had ascended the previous evening, and strained his view to catch every peculiarity of the landscape; but it wore the same wild, barren aspect when seen by the rays of the morning sun which it had done when surveyed by the fading glimmer of eve. Descending into the grotto, he lifted the stone, filled his pockets with gems, put the box together as well and securely as he could, sprinkled fresh sand over the spot from which it had been taken, and then carefully trod down the earth to give it everywhere a uniform appearance; then, quitting the grotto, he replaced the stone, heaping on it broken masses of rocks and rough fragments of crumbling granite, filling the interstices with earth, into which he deftly inserted rapidly growing plants, such as the wild myrtle and flowering thorn, then carefully watering these new plantations, he scrupulously effaced every trace of footsteps, leaving the approach to the cavern as savage-looking and untrodden as he had found it. This done, he impatiently awaited the return of his companions. To wait at Monte Cristo for the purpose of watching like a dragon over the almost incalculable riches that had thus fallen into his possession satisfied not the cravings of his heart, which yearned to return to dwell among mankind, and to assume the rank, power, and influence which are always accorded to wealth—that first and greatest of all the forces within the grasp of man. On the sixth day, the smugglers returned. From a distance Dantès recognized the rig and handling of La Jeune Amélie, and dragging himself with affected difficulty towards the landing-place, he met his companions with an assurance that, although considerably better than when they quitted him, he still suffered acutely from his late accident. He then inquired how they had fared in their trip. To this question the smugglers replied that, although successful in landing their cargo in safety, they had scarcely done so when they received intelligence that a guard-ship had just quitted the port of Toulon and was crowding all sail towards them. This obliged them to make all the speed they could to evade the enemy, when they could but lament the absence of Dantès, whose superior skill in the management of a vessel would have availed them so materially. In fact, the pursuing vessel had almost overtaken them when, fortunately, night came on, and enabled them to double the Cape of Corsica, and so elude all further pursuit. Upon the whole, however, the trip had been sufficiently successful to satisfy all concerned; while the crew, and particularly Jacopo, expressed great regrets that Dantès had not been an equal sharer with themselves in the profits, which amounted to no less a sum than fifty piastres each. Edmond preserved the most admirable self-command, not suffering the faintest indication of a smile to escape him at the enumeration of all the benefits he would have reaped had he been able to quit the island; but as La Jeune Amélie had merely come to Monte Cristo to fetch him away, he embarked that same evening, and proceeded with the captain to Leghorn. Arrived at Leghorn, he repaired to the house of a Jew, a dealer in precious stones, to whom he disposed of four of his smallest diamonds for five thousand francs each. Dantès half feared that such valuable jewels in the hands of a poor sailor like himself might excite suspicion; but the cunning purchaser asked no troublesome questions concerning a bargain by which he gained a round profit of at least eighty per cent. The following day Dantès presented Jacopo with an entirely new vessel, accompanying the gift by a donation of one hundred piastres, that he might provide himself with a suitable crew and other requisites for his outfit, upon condition that he would go at once to Marseilles for the purpose of inquiring after an old man named Louis Dantès, residing in the Allées de Meilhan, and also a young woman called Mercédès, an inhabitant of the Catalan village. Jacopo could scarcely believe his senses at receiving this magnificent present, which Dantès hastened to account for by saying that he had merely been a sailor from whim and a desire to spite his family, who did not allow him as much money as he liked to spend; but that on his arrival at Leghorn he had come into possession of a large fortune, left him by an uncle, whose sole heir he was. The superior education of Dantès gave an air of such extreme probability to this statement that it never once occurred to Jacopo to doubt its accuracy. The term for which Edmond had engaged to serve on board La Jeune Amélie having expired, Dantès took leave of the captain, who at first tried all his powers of persuasion to induce him to remain as one of the crew, but having been told the history of the legacy, he ceased to importune him further. The following morning Jacopo set sail for Marseilles, with directions from Dantès to join him at the Island of Monte Cristo. Having seen Jacopo fairly out of the harbor, Dantès proceeded to make his final adieus on board La Jeune Amélie, distributing so liberal a gratuity among her crew as to secure for him the good wishes of all, and expressions of cordial interest in all that concerned him. To the captain he promised to write when he had made up his mind as to his future plans. Then Dantès departed for Genoa. At the moment of his arrival a small yacht was under trial in the bay; this yacht had been built by order of an Englishman, who, having heard that the Genoese excelled all other builders along the shores of the Mediterranean in the construction of fast-sailing vessels, was desirous of possessing a specimen of their skill; the price agreed upon between the Englishman and the Genoese builder was forty thousand francs. Dantès, struck with the beauty and capability of the little vessel, applied to its owner to transfer it to him, offering sixty thousand francs, upon condition that he should be allowed to take immediate possession. The proposal was too advantageous to be refused, the more so as the person for whom the yacht was intended had gone upon a tour through Switzerland, and was not expected back in less than three weeks or a month, by which time the builder reckoned upon being able to complete another. A bargain was therefore struck. Dantès led the owner of the yacht to the dwelling of a Jew; retired with the latter for a few minutes to a small back parlor, and upon their return the Jew counted out to the shipbuilder the sum of sixty thousand francs in bright gold pieces. The delighted builder then offered his services in providing a suitable crew for the little vessel, but this Dantès declined with many thanks, saying he was accustomed to cruise about quite alone, and his principal pleasure consisted in managing his yacht himself; the only thing the builder could oblige him in would be to contrive a sort of secret closet in the cabin at his bed’s head, the closet to contain three divisions, so constructed as to be concealed from all but himself. The builder cheerfully undertook the commission, and promised to have these secret places completed by the next day, Dantès furnishing the dimensions and plan in accordance with which they were to be constructed. Two hours afterward Dantès sailed from the port of Genoa, under the inspection of an immense crowd drawn together by curiosity to see the rich Spanish nobleman who preferred managing his own yacht. But their wonder was soon changed to admiration at seeing the perfect skill with which Dantès handled the helm. The boat, indeed, seemed to be animated with almost human intelligence, so promptly did it obey the slightest touch; and Dantès required but a short trial of his beautiful craft to acknowledge that the Genoese had not without reason attained their high reputation in the art of shipbuilding. The spectators followed the little vessel with their eyes as long as it remained visible; they then turned their conjectures upon her probable destination. Some insisted she was making for Corsica, others the Island of Elba; bets were offered to any amount that she was bound for Spain; while Africa was positively reported by many persons as her intended course; but no one thought of Monte Cristo. Yet thither it was that Dantès guided his vessel, and at Monte Cristo he arrived at the close of the second day; his boat had proved herself a first-class sailor, and had come the distance from Genoa in thirty-five hours. Dantès had carefully noted the general appearance of the shore, and, instead of landing at the usual place, he dropped anchor in the little creek. The island was utterly deserted, and bore no evidence of having been visited since he went away; his treasure was just as he had left it. Early on the following morning he commenced the removal of his riches, and ere nightfall the whole of his immense wealth was safely deposited in the compartments of the secret locker. A week passed by. Dantès employed it in manœuvring his yacht round the island, studying it as a skilful horseman would the animal he destined for some important service, till at the end of that time he was perfectly conversant with its good and bad qualities. The former Dantès proposed to augment, the latter to remedy. Upon the eighth day he discerned a small vessel under full sail approaching Monte Cristo. As it drew near, he recognized it as the boat he had given to Jacopo. He immediately signalled it. His signal was returned, and in two hours afterwards the new-comer lay at anchor beside the yacht. A mournful answer awaited each of Edmond’s eager inquiries as to the information Jacopo had obtained. Old Dantès was dead, and Mercédès had disappeared. Dantès listened to these melancholy tidings with outward calmness; but, leaping lightly ashore, he signified his desire to be quite alone. In a couple of hours he returned. Two of the men from Jacopo’s boat came on board the yacht to assist in navigating it, and he gave orders that she should be steered direct to Marseilles. For his father’s death he was in some manner prepared; but he knew not how to account for the mysterious disappearance of Mercédès. Without divulging his secret, Dantès could not give sufficiently clear instructions to an agent. There were, besides, other particulars he was desirous of ascertaining, and those were of a nature he alone could investigate in a manner satisfactory to himself. His looking-glass had assured him, during his stay at Leghorn, that he ran no risk of recognition; moreover, he had now the means of adopting any disguise he thought proper. One fine morning, then, his yacht, followed by the little fishing-boat, boldly entered the port of Marseilles, and anchored exactly opposite the spot from whence, on the never-to-be-forgotten night of his departure for the Château d’If, he had been put on board the boat destined to convey him thither. Still Dantès could not view without a shudder the approach of a gendarme who accompanied the officers deputed to demand his bill of health ere the yacht was permitted to hold communication with the shore; but with that perfect self-possession he had acquired during his acquaintance with Faria, Dantès coolly presented an English passport he had obtained from Leghorn, and as this gave him a standing which a French passport would not have afforded, he was informed that there existed no obstacle to his immediate debarkation. The first person to attract the attention of Dantès, as he landed on the Canebière, was one of the crew belonging to the Pharaon. Edmond welcomed the meeting with this fellow—who had been one of his own sailors—as a sure means of testing the extent of the change which time had worked in his own appearance. Going straight towards him, he propounded a variety of questions on different subjects, carefully watching the man’s countenance as he did so; but not a word or look implied that he had the slightest idea of ever having seen before the person with whom he was then conversing. Giving the sailor a piece of money in return for his civility, Dantès proceeded onwards; but ere he had gone many steps he heard the man loudly calling him to stop. Dantès instantly turned to meet him. “I beg your pardon, sir,” said the honest fellow, in almost breathless haste, “but I believe you made a mistake; you intended to give me a two-franc piece, and see, you gave me a double Napoleon.” “Thank you, my good friend. I see that I have made a trifling mistake, as you say; but by way of rewarding your honesty I give you another double Napoleon, that you may drink to my health, and be able to ask your messmates to join you.” So extreme was the surprise of the sailor, that he was unable even to thank Edmond, whose receding figure he continued to gaze after in speechless astonishment. “Some nabob from India,” was his comment. Dantès, meanwhile, went on his way. Each step he trod oppressed his heart with fresh emotion; his first and most indelible recollections were there; not a tree, not a street, that he passed but seemed filled with dear and cherished memories. And thus he proceeded onwards till he arrived at the end of the Rue de Noailles, from whence a full view of the Allées de Meilhan was obtained. At this spot, so pregnant with fond and filial remembrances, his heart beat almost to bursting, his knees tottered under him, a mist floated over his sight, and had he not clung for support to one of the trees, he would inevitably have fallen to the ground and been crushed beneath the many vehicles continually passing there. Recovering himself, however, he wiped the perspiration from his brows, and stopped not again till he found himself at the door of the house in which his father had lived. The nasturtiums and other plants, which his father had delighted to train before his window, had all disappeared from the upper part of the house. Leaning against the tree, he gazed thoughtfully for a time at the upper stories of the shabby little house. Then he advanced to the door, and asked whether there were any rooms to be let. Though answered in the negative, he begged so earnestly to be permitted to visit those on the fifth floor, that, in despite of the oft-repeated assurance of the concierge that they were occupied, Dantès succeeded in inducing the man to go up to the tenants, and ask permission for a gentleman to be allowed to look at them. The tenants of the humble lodging were a young couple who had been scarcely married a week; and seeing them, Dantès sighed heavily. Nothing in the two small chambers forming the apartments remained as it had been in the time of the elder Dantès; the very paper was different, while the articles of antiquated furniture with which the rooms had been filled in Edmond’s time had all disappeared; the four walls alone remained as he had left them. The bed belonging to the present occupants was placed as the former owner of the chamber had been accustomed to have his; and, in spite of his efforts to prevent it, the eyes of Edmond were suffused in tears as he reflected that on that spot the old man had breathed his last, vainly calling for his son. The young couple gazed with astonishment at the sight of their visitor’s emotion, and wondered to see the large tears silently chasing each other down his otherwise stern and immovable features; but they felt the sacredness of his grief, and kindly refrained from questioning him as to its cause, while, with instinctive delicacy, they left him to indulge his sorrow alone. When he withdrew from the scene of his painful recollections, they both accompanied him downstairs, reiterating their hope that he would come again whenever he pleased, and assuring him that their poor dwelling would ever be open to him. As Edmond passed the door on the fourth floor, he paused to inquire whether Caderousse the tailor still dwelt there; but he received for reply, that the person in question had got into difficulties, and at the present time kept a small inn on the route from Bellegarde to Beaucaire. Having obtained the address of the person to whom the house in the Allées de Meilhan belonged, Dantès next proceeded thither, and, under the name of Lord Wilmore (the name and title inscribed on his passport), purchased the small dwelling for the sum of twenty-five thousand francs, at least ten thousand more than it was worth; but had its owner asked half a million, it would unhesitatingly have been given. The very same day the occupants of the apartments on the fifth floor of the house, now become the property of Dantès, were duly informed by the notary who had arranged the necessary transfer of deeds, etc., that the new landlord gave them their choice of any of the rooms in the house, without the least augmentation of rent, upon condition of their giving instant possession of the two small chambers they at present inhabited. This strange event aroused great wonder and curiosity in the neighborhood of the Allées de Meilhan, and a multitude of theories were afloat, none of which was anywhere near the truth. But what raised public astonishment to a climax, and set all conjecture at defiance, was the knowledge that the same stranger who had in the morning visited the Allées de Meilhan had been seen in the evening walking in the little village of the Catalans, and afterwards observed to enter a poor fisherman’s hut, and to pass more than an hour in inquiring after persons who had either been dead or gone away for more than fifteen or sixteen years. But on the following day the family from whom all these particulars had been asked received a handsome present, consisting of an entirely new fishing-boat, with two seines and a tender. The delighted recipients of these munificent gifts would gladly have poured out their thanks to their generous benefactor, but they had seen him, upon quitting the hut, merely give some orders to a sailor, and then springing lightly on horseback, leave Marseilles by the Porte d’Aix. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Urbana, Illinois: Project Gutenberg. Retrieved April 2022, from Dumas, Alexandre. 2022. The Count of the Monte-Cristo. https://www.gutenberg.org/files/1184/1184-h/1184-h.htm#linkC2HCH0025 This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever.  You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at . www.gutenberg.org https://www.gutenberg.org/policy/license.html

The Count of Monte Cristo, Illustrated: Chapter 25 - The Unknown

The Count of Monte Cristo,by Alexandre Dumas, père is part of . You can jump to any chapter in this book here: . Volume One, Chapter 2: Father and Son HackerNoon’s Book Blog Post series [LINK TO TABLE OF LINK] Chapter 2. Father and Son We will leave Danglars struggling with the demon of hatred, and endeavoring to insinuate in the ear of the shipowner some evil suspicions against his comrade, and follow Dantès, who, after having traversed La Canebière, took the Rue de Noailles, and entering a small house, on the left of the Allées de Meilhan, rapidly ascended four flights of a dark staircase, holding the baluster with one hand, while with the other he repressed the beatings of his heart, and paused before a half-open door, from which he could see the whole of a small room. This room was occupied by Dantès’ father. The news of the arrival of the Pharaon had not yet reached the old man, who, mounted on a chair, was amusing himself by training with trembling hand the nasturtiums and sprays of clematis that clambered over the trellis at his window. Suddenly, he felt an arm thrown around his body, and a well-known voice behind him exclaimed, “Father—dear father!” The old man uttered a cry, and turned round; then, seeing his son, he fell into his arms, pale and trembling. “What ails you, my dearest father? Are you ill?” inquired the young man, much alarmed. “No, no, my dear Edmond—my boy—my son!—no; but I did not expect you; and joy, the surprise of seeing you so suddenly—Ah, I feel as if I were going to die.” “Come, come, cheer up, my dear father! ’Tis I—really I! They say joy never hurts, and so I came to you without any warning. Come now, do smile, instead of looking at me so solemnly. Here I am back again, and we are going to be happy.” “Yes, yes, my boy, so we will—so we will,” replied the old man; “but how shall we be happy? Shall you never leave me again? Come, tell me all the good fortune that has befallen you.” “God forgive me,” said the young man, “for rejoicing at happiness derived from the misery of others, but, Heaven knows, I did not seek this good fortune; it has happened, and I really cannot pretend to lament it. The good Captain Leclere is dead, father, and it is probable that, with the aid of M. Morrel, I shall have his place. Do you understand, father? Only imagine me a captain at twenty, with a hundred louis pay, and a share in the profits! Is this not more than a poor sailor like me could have hoped for?” “Yes, my dear boy,” replied the old man, “it is very fortunate.” “Well, then, with the first money I touch, I mean you to have a small house, with a garden in which to plant clematis, nasturtiums, and honeysuckle. But what ails you, father? Are you not well?” “’Tis nothing, nothing; it will soon pass away”—and as he said so the old man’s strength failed him, and he fell backwards. “Come, come,” said the young man, “a glass of wine, father, will revive you. Where do you keep your wine?” “No, no; thanks. You need not look for it; I do not want it,” said the old man. “Yes, yes, father, tell me where it is,” and he opened two or three cupboards. “It is no use,” said the old man, “there is no wine.” “What, no wine?” said Dantès, turning pale, and looking alternately at the hollow cheeks of the old man and the empty cupboards. “What, no wine? Have you wanted money, father?” “I want nothing now that I have you,” said the old man. “Yet,” stammered Dantès, wiping the perspiration from his brow,—“yet I gave you two hundred francs when I left, three months ago.” “Yes, yes, Edmond, that is true, but you forgot at that time a little debt to our neighbor, Caderousse. He reminded me of it, telling me if I did not pay for you, he would be paid by M. Morrel; and so, you see, lest he might do you an injury——” “Well?” “Why, I paid him.” “But,” cried Dantès, “it was a hundred and forty francs I owed Caderousse.” “Yes,” stammered the old man. “And you paid him out of the two hundred francs I left you?” The old man nodded. “So that you have lived for three months on sixty francs,” muttered Edmond. “You know how little I require,” said the old man. “Heaven pardon me,” cried Edmond, falling on his knees before his father. “What are you doing?” “You have wounded me to the heart.” “Never mind it, for I see you once more,” said the old man; “and now it’s all over—everything is all right again.” “Yes, here I am,” said the young man, “with a promising future and a little money. Here, father, here!” he said, “take this—take it, and send for something immediately.” And he emptied his pockets on the table, the contents consisting of a dozen gold pieces, five or six five-franc pieces, and some smaller coin. The countenance of old Dantès brightened. “Whom does this belong to?” he inquired. “To me, to you, to us! Take it; buy some provisions; be happy, and tomorrow we shall have more.” “Gently, gently,” said the old man, with a smile; “and by your leave I will use your purse moderately, for they would say, if they saw me buy too many things at a time, that I had been obliged to await your return, in order to be able to purchase them.” “Do as you please; but, first of all, pray have a servant, father. I will not have you left alone so long. I have some smuggled coffee and most capital tobacco, in a small chest in the hold, which you shall have tomorrow. But, hush, here comes somebody.” “’Tis Caderousse, who has heard of your arrival, and no doubt comes to congratulate you on your fortunate return.” “Ah, lips that say one thing, while the heart thinks another,” murmured Edmond. “But, never mind, he is a neighbor who has done us a service on a time, so he’s welcome.” As Edmond paused, the black and bearded head of Caderousse appeared at the door. He was a man of twenty-five or six, and held a piece of cloth, which, being a tailor, he was about to make into a coat-lining. “What, is it you, Edmond, back again?” said he, with a broad Marseillaise accent, and a grin that displayed his ivory-white teeth. “Yes, as you see, neighbor Caderousse; and ready to be agreeable to you in any and every way,” replied Dantès, but ill-concealing his coldness under this cloak of civility. “Thanks—thanks; but, fortunately, I do not want for anything; and it chances that at times there are others who have need of me.” Dantès made a gesture. “I do not allude to you, my boy. No!—no! I lent you money, and you returned it; that’s like good neighbors, and we are quits.” “We are never quits with those who oblige us,” was Dantès’ reply; “for when we do not owe them money, we owe them gratitude.” “What’s the use of mentioning that? What is done is done. Let us talk of your happy return, my boy. I had gone on the quay to match a piece of mulberry cloth, when I met friend Danglars. ‘You at Marseilles?’—‘Yes,’ says he. “‘I thought you were at Smyrna.’—‘I was; but am now back again.’ “‘And where is the dear boy, our little Edmond?’ “‘Why, with his father, no doubt,’ replied Danglars. And so I came,” added Caderousse, “as fast as I could to have the pleasure of shaking hands with a friend.” “Worthy Caderousse!” said the old man, “he is so much attached to us.” “Yes, to be sure I am. I love and esteem you, because honest folks are so rare. But it seems you have come back rich, my boy,” continued the tailor, looking askance at the handful of gold and silver which Dantès had thrown on the table. The young man remarked the greedy glance which shone in the dark eyes of his neighbor. “Eh,” he said, negligently, “this money is not mine. I was expressing to my father my fears that he had wanted many things in my absence, and to convince me he emptied his purse on the table. Come, father” added Dantès, “put this money back in your box—unless neighbor Caderousse wants anything, and in that case it is at his service.” “No, my boy, no,” said Caderousse. “I am not in any want, thank God, my living is suited to my means. Keep your money—keep it, I say;—one never has too much;—but, at the same time, my boy, I am as much obliged by your offer as if I took advantage of it.” “It was offered with good will,” said Dantès. “No doubt, my boy; no doubt. Well, you stand well with M. Morrel I hear,—you insinuating dog, you!” “M. Morrel has always been exceedingly kind to me,” replied Dantès. “Then you were wrong to refuse to dine with him.” “What, did you refuse to dine with him?” said old Dantès; “and did he invite you to dine?” “Yes, my dear father,” replied Edmond, smiling at his father’s astonishment at the excessive honor paid to his son. “And why did you refuse, my son?” inquired the old man. “That I might the sooner see you again, my dear father,” replied the young man. “I was most anxious to see you.” “But it must have vexed M. Morrel, good, worthy man,” said Caderousse. “And when you are looking forward to be captain, it was wrong to annoy the owner.” “But I explained to him the cause of my refusal,” replied Dantès, “and I hope he fully understood it.” “Yes, but to be captain one must do a little flattery to one’s patrons.” “I hope to be captain without that,” said Dantès. “So much the better—so much the better! Nothing will give greater pleasure to all your old friends; and I know one down there behind the Saint Nicolas citadel who will not be sorry to hear it.” “Mercédès?” said the old man. “Yes, my dear father, and with your permission, now I have seen you, and know you are well and have all you require, I will ask your consent to go and pay a visit to the Catalans.” “Go, my dear boy,” said old Dantès; “and Heaven bless you in your wife, as it has blessed me in my son!” “His wife!” said Caderousse; “why, how fast you go on, father Dantès; she is not his wife yet, as it seems to me.” “No, but according to all probability she soon will be,” replied Edmond. “Yes—yes,” said Caderousse; “but you were right to return as soon as possible, my boy.” “And why?” “Because Mercédès is a very fine girl, and fine girls never lack followers; she particularly has them by dozens.” “Really?” answered Edmond, with a smile which had in it traces of slight uneasiness. “Ah, yes,” continued Caderousse, “and capital offers, too; but you know, you will be captain, and who could refuse you then?” “Meaning to say,” replied Dantès, with a smile which but ill-concealed his trouble, “that if I were not a captain——” “Eh—eh!” said Caderousse, shaking his head. “Come, come,” said the sailor, “I have a better opinion than you of women in general, and of Mercédès in particular; and I am certain that, captain or not, she will remain ever faithful to me.” “So much the better—so much the better,” said Caderousse. “When one is going to be married, there is nothing like implicit confidence; but never mind that, my boy,—go and announce your arrival, and let her know all your hopes and prospects.” “I will go directly,” was Edmond’s reply; and, embracing his father, and nodding to Caderousse, he left the apartment. Caderousse lingered for a moment, then taking leave of old Dantès, he went downstairs to rejoin Danglars, who awaited him at the corner of the Rue Senac. “Well,” said Danglars, “did you see him?” “I have just left him,” answered Caderousse. “Did he allude to his hope of being captain?” “He spoke of it as a thing already decided.” “Indeed!” said Danglars, “he is in too much hurry, it appears to me.” “Why, it seems M. Morrel has promised him the thing.” “So that he is quite elated about it?” “Why, yes, he is actually insolent over the matter—has already offered me his patronage, as if he were a grand personage, and proffered me a loan of money, as though he were a banker.” “Which you refused?” “Most assuredly; although I might easily have accepted it, for it was I who put into his hands the first silver he ever earned; but now M. Dantès has no longer any occasion for assistance—he is about to become a captain.” “Pooh!” said Danglars, “he is not one yet.” “Ma foi! it will be as well if he is not,” answered Caderousse; “for if he should be, there will be really no speaking to him.” “If we choose,” replied Danglars, “he will remain what he is; and perhaps become even less than he is.” “What do you mean?” “Nothing—I was speaking to myself. And is he still in love with the Catalane?” “Over head and ears; but, unless I am much mistaken, there will be a storm in that quarter.” “Explain yourself.” “Why should I?” “It is more important than you think, perhaps. You do not like Dantès?” “I never like upstarts.” “Then tell me all you know about the Catalane.” “I know nothing for certain; only I have seen things which induce me to believe, as I told you, that the future captain will find some annoyance in the vicinity of the Vieilles Infirmeries.” “What have you seen?—come, tell me!” “Well, every time I have seen Mercédès come into the city she has been accompanied by a tall, strapping, black-eyed Catalan, with a red complexion, brown skin, and fierce air, whom she calls cousin.” “Really; and you think this cousin pays her attentions?” “I only suppose so. What else can a strapping chap of twenty-one mean with a fine wench of seventeen?” “And you say that Dantès has gone to the Catalans?” “He went before I came down.” “Let us go the same way; we will stop at La Réserve, and we can drink a glass of La Malgue, whilst we wait for news.” “Come along,” said Caderousse; “but you pay the score.” “Of course,” replied Danglars; and going quickly to the designated place, they called for a bottle of wine, and two glasses. Père Pamphile had seen Dantès pass not ten minutes before; and assured that he was at the Catalans, they sat down under the budding foliage of the planes and sycamores, in the branches of which the birds were singing their welcome to one of the first days of spring. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Urbana, Illinois: Project Gutenberg. Retrieved April 2022, from Dumas, Alexandre. 2022. The Count of the Monte-Cristo. https://www.gutenberg.org/files/1184/1184-h/1184-h.htm#linkC2HCH0002 This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever.  You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at . www.gutenberg.org https://www.gutenberg.org/policy/license.html

The Count of Monte Cristo, Illustrated: Chapter 2 - Father and Son

The answer is pretty straightforward if you need a response. But what if you don't want to wait for a reply? Non-Waiting HTTP Consider the case of a Lambda function that after processing, accumulates some metrics and then emits those back to a REST aggregator service for processing. If the metrics are counters, it may not matter if the metrics request fails occasionally, as the next request will send the updated counter totals. In cases like these, it will be faster not to wait for the HTTP response. So how should we do this in NodeJS? Let's look first at a naive example request (without error handling) where we wait for the response. Just for this example, we'll create an async "request" node function that returns a promise that we can wait on. const https = require('https')
const URL = require('url')

async function request(url, data) {
    return new Promise((resolve, reject) => {
        let req = https.request(URL.parse(url), function (res) {
            let body = ''
            res.on('data', (chunk) => { body += chunk })
            res.on('end', () => { resolve(body) })
        })
        req.write(data)
        req.end()
    })
} Our Lambda would then look like: exports.handler = async (event, context) {
    ...
    let result = await request('https://metric-service.com', metrics)
    return result
} To invoke our HTTP request inside a Lambda, we use "await" which issues the request and then waits for the response. If the metric aggregator service takes 950 milliseconds to process the request and return a status code, we will be billed for an additional second on every invocation. During this wait time, our Lambda function is asleep, but AWS is still billing us for that time. With AWS Lambda, you are billed for elapsed time, not for utilized CPU time. While Lambda is extraordinarily cheap, with high transaction volumes, these short waits of 950 milliseconds can add up to a significant bill. Don't Wait So what happens if we simply do not call "await" and thus not wait on the response from our HTTP request? exports.handler = async (event, context) {
    /* nowait */ request('https://example.com', metrics)
    return 'done'
} Strange Things Happen Sometimes the request is sent and sometimes the request is not. Sometimes the request is received immediately by the metrics aggregator and sometimes the request is received after our Lambda next runs. What is happening? Freezing Lambda Containers Lambda functions run inside an AWS Firecracker container. When you return from your Lambda function, AWS immediately freezes the container and its global state. When the Lambda is next invoked, it will thaw the container to service the new invocation. If we send a HTTP request and that request is not fully sent over the network and we return from the Lambda function, AWS will immediately suspend our Lambda container AND the partially sent request will be suspended as well. The request will remain frozen until the Lambda is next invoked and the Node event loop will then resume processing and the request will be fully transmitted. How to Solve? We could try a short sleep to give time for the request to be sent? But how long should we wait. exports.handler = async (event, context) {
    /* nowait */ request('https://example.com', metrics)
    await sleep(100)
    return 'done'
} This hardly seems reliable. Wait for Request Transmission The correct solution is to use the Node API and wait until the request is fully sent, but not wait for the response to be received. req.end(,,callback) Here is a sample: const https = require('https')
const URL = require('url')

async function request(url, data) {
    return new Promise((resolve, reject) => {
        let req = https.request(URL.parse(url))
        req.write(data)
        req.end(null, null, () => {
            /* Request has been fully sent */
            resolve(req)
        })
    })
} Notice that the request is resolved via the end callback on the "req" object and not on the "res" object in the previous example. This modified request function should be invoked by our Lambda with "await". In this case, we are not waiting for the HTTP response, but rather for the request to be fully sent. This is much faster than the 750 milliseconds to receive our metrics response, typically under 20 milliseconds. exports.handler = async (event, context) {
    await request('https://example.com', metrics)
    return 'done'
} Alternative Design Patterns There are many other excellent ways to avoid waiting and blocking in Lambda functions such as using Step functions, SQS queues and directly invoking Lambda functions as events without waiting. Consider the best approach for your app, but if you must use HTTP and you don't need to wait for a response, consider the technique above to lower your wait time and AWS bill. SenseDeep Our SenseDeep Serverless Developer Studio uses this technique in a Watcher Lambda that monitors your Lambdas, runs alarms and ingests log data. We needed the Watcher to be exceptionally fast and not wait for any REST/HTTP API requests. So the Watcher uses this non-waiting technique when sending status back to the SenseDeep service. To learn more about the SenseDeep Serverless Developer Studio and try it for free, please go to: . https://www.sensedeep.com References Here are some other good reads about Lambda and AWS asynchronous programming. Node event loop freezing: https://levelup.gitconnected.com/avoiding-the-pitfalls-of-async-node-js-functions-in-aws-lambda-941220582e7a Lambda Billing: https://www.jeremydaly.com/serverless-tip-dont-overpay-when-waiting-on-remote-api-calls/ Async programming: https://read.acloud.guru/save-time-and-money-with-aws-lambda-using-asynchronous-programming-3548ea65f751 Perils of step functions: https://blog.scottlogic.com/2018/06/19/step-functions.html Invoke Lambda async: https://docs.aws.amazon.com/lambda/latest/dg/invocation-async.html Lambda invocation overview: https://docs.aws.amazon.com/lambda/latest/dg/lambda-invocation.html

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