Asynchronous programming in Node.js

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Asynchronous programming in Node.js

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Asynchronous programming

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Asynchronous programming

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Asynchronous programming

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Asynchronous

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English Definition of

Adjective1. Not occurring at the same time.2. Controlling the timing of operations by the use of pulses sent

when the previous operation is completed rather than at regular intervals.

Source:https://en.oxforddictionaries.com/definition/asynchronous

Asynchronous

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English Definition of

Adjective1. Not occurring at the same time.2. Controlling the timing of operations by the use of events sent

when the previous operation is completed rather than at regular intervals.

Source: A. Maccagnan

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One step back

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What is Node.js?

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Source: Giacomo Fornari, Flipped classroom. Sistemi Concorrenti e Distribuiti 2016/2017,

http://www.slideshare.net/GiacomoFornari/nodejs-concurrency-68682939.

What is Node.js?

What is Node.js?

● Event-driven● I/O● Server-side● Javascript environment● Based on V8

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What is Node.js?

5. Event-driven4. I/O3. Server side1. Javascript environment2. Based on V8

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What is Node.js?

5. Event-driven4. I/O3. Server side1. Javascript environment2. Based on V8

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What is Node.js?

2. Based on V8

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Source: https://www.diva-portal.org/smash/get/diva2:550993/FULLTEXT01.pdf

What is Node.js?

5. Event-driven4. I/O3. Server side1. Javascript environment2. Based on V8

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What is Node.js?

5. Event-driven4. I/O3. Server side1. Javascript environment2. Based on V8

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What is Node.js?

4. I/O

Source: Understanding the node.js event loop, http://blog.mixu.net/2011/02/01/understanding-the-node-js-event-loop

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What is Node.js?

5. Event-driven4. I/O3. Server side1. Javascript environment2. Based on V8

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What is Node.js?

5. Event-drivenMuch of the Node.js core API is built around an idiomatic asynchronous

event-driven architecture in which certain kinds of objects (called

"emitters") periodically emit named events that cause Function objects

("listeners") to be called.

Source:

https://nodejs.org/api/events.html#events_passing_arguments_and_this

_to_listeners

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What is Node.js?

5. Event-drivenMuch of the Node.js core API is built around an idiomatic asynchronous

event-driven architecture in which certain kinds of objects (called

"emitters") periodically emit named events that cause Function objects

("listeners") to be called.

Source:

https://nodejs.org/api/events.html#events_passing_arguments_and_this

_to_listeners

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What is Node.js?

5. Event-driven

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What is Node.js?

5. Event-driven

Source: http://abdelraoof.com/blog/2015/10/28/understanding-nodejs-event-loop

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Asynchronous programming

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Must read: http://journal.stuffwithstuff.com/2015/02/01/what-color-is-your-function

ExamplesCode could be found here:

https://github.com/alemhnan/SWE.UNIPD

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