Professional Courses
Industry-relevant training in Business, Technology, and Design to help professionals and graduates upskill for real-world careers.
Categories
Interactive Games
Fun, engaging games to boost memory, math fluency, typing speed, and English skillsβperfect for learners of all ages.
Typing
Memory
Math
English Adventures
Knowledge
Enroll to start learning
Youβve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take mock test.
Interactive Audio Lesson
Listen to a student-teacher conversation explaining the topic in a relatable way.
Introduction to Async Programming
Unlock Audio Lesson
Signup and Enroll to the course for listening the Audio Lesson
Class, today we're discussing asynchronous programming. Can anyone tell me what they think asynchronous means?
Does it mean something can happen at the same time?
Exactly, asynchronous programming allows concurrent execution of tasks without waiting. It is particularly useful for I/O-bound tasks where the program can continue running rather than being blocked. Let's remember: 'I/O stands for Input/Output.'
How is that different from regular programming?
Great question! In traditional programming, tasks are performed in sequence, often blocking the program from executing while it waits for operations like file reading. Asynchronous programming is designed to be non-blocking. Any examples of when this might be useful?
Maybe when downloading multiple files from the internet at once?
Absolutely! The async programming model is ideal for operations like that.
Understanding Coroutines and the Event Loop
Unlock Audio Lesson
Signup and Enroll to the course for listening the Audio Lesson
Now, let's talk about coroutines, which are the building blocks of asynchronous programming. Who can tell me what a coroutine is?
Is it like a normal function but it can pause?
That's correct! A coroutine is defined using `async def` and can pause using `await`. This helps efficiently manage tasks. Now, can anyone explain what an event loop does?
It runs the coroutine and schedules other tasks, right?
Exactly! The event loop is central to asyncio, allowing all coroutines to run and await completion.
What happens if you forget to await a coroutine?
If you forget to await, you'll just get a coroutine object that isn't executed. Remember, always await coroutines for them to run!
Using asyncio to Manage I/O-Bound Tasks
Unlock Audio Lesson
Signup and Enroll to the course for listening the Audio Lesson
Let's look at how we can use asyncio for I/O-bound tasks. What tasks can you think of that might be I/O-bound?
Connecting to a database?
Correct! Connecting to a database or making web requests are great examples. We can run multiple asynchronous tasks concurrently. How does that help us?
It saves time since we don't wait for one to finish before starting another.
Exactly! This means we can handle many operations even with limited resources. Can someone tell me how we could implement multiple fetch operations?
We could use `asyncio.gather()` to run them all together.
Perfect! Using `asyncio.gather()` allows us to run multiple tasks and wait for their completion together.
Introduction & Overview
Read a summary of the section's main ideas. Choose from Basic, Medium, or Detailed.
Quick Overview
Standard
Asynchronous programming allows tasks to run concurrently without waiting for each to complete. The section covers foundational concepts like coroutines, the event loop, and how Python's asyncio library facilitates efficient I/O-bound operations through constructs like async functions, await expressions, and task management.
Detailed
Key Concepts of Asynchronous Programming with asyncio
Asynchronous programming is a programming paradigm that facilitates performing tasks concurrently without waiting for each task's completion. This is especially significant for I/O-bound operations, which involve waiting for external systems, such as network communication or file handling.
In Python, the asyncio library provides built-in functionality to write asynchronous code using async and await keywords introduced in Python 3.5.
Key Points:
- Coroutines: Defined using
async defand allow the function to pause and resume, introduced withawait. - Event Loop: Central to asyncio, this constructs schedules, runs coroutines and manages concurrent tasks.
- Tasks: Coroutines can be converted into tasks using
asyncio.create_task(), enabling multiple concurrent executions. - I/O-bound operations: Asynchronous code shines here because it allows a program to continue executing while waiting for I/O operations to complete.
Using asyncio, developers can create complex applications like network servers or clients and efficiently handle extensive concurrent tasks. This paradigm overcomes the limitations of traditional blocking code by utilizing a single thread for I/O operations, resulting in better performance and scalability.
Audio Book
Dive deep into the subject with an immersive audiobook experience.
Declaring a Coroutine
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
β async def: Declares a coroutine.
Detailed Explanation
In Python, the keyword 'async' is used to declare a coroutine. A coroutine is a special type of function that can pause execution and yield control back to the event loop. This allows other tasks to run while waiting for a long-running operation, such as fetching data from a database or waiting for a network response.
Examples & Analogies
Think of a coroutine like a cook in a restaurant. Instead of standing idle while waiting for the oven timer to beep, the cook can prep other ingredients. Once the oven timer goes off, the cook returns to take the dish out.
Pausing Execution
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
β await: Pauses execution until the awaited coroutine completes.
Detailed Explanation
The 'await' keyword is used when calling an asynchronous function (coroutine). When a coroutine hits an 'await' statement, it pauses its execution and hands control back to the event loop, allowing it to run other tasks until the awaited coroutine is complete. This means that rather than blocking, the program can continue to execute while waiting.
Examples & Analogies
Imagine you are on hold during a phone call. You can't talk until the representative picks up, but you can still listen to music or browse the internet in the meantime.
Handling Coroutines
Unlock Audio Book
Signup and Enroll to the course for listening the Audio Book
β Coroutines must be awaited; otherwise, they return a coroutine object (not executed yet).
Detailed Explanation
If a coroutine is called without the 'await' keyword, it does not run immediately. Instead, it returns a coroutine object, which is essentially a placeholder that can be executed later with 'await'. It's crucial to always 'await' the coroutine to ensure that it runs as expected and does not lead to unintended behavior.
Examples & Analogies
Consider a movie ticket that you've purchased for a future date. If you donβt show up at the theater on that day, you won't be able to see the movie; similarly, without 'await', the coroutine wonβt execute until explicitly called.
Definitions & Key Concepts
Learn essential terms and foundational ideas that form the basis of the topic.
Key Concepts
-
Asynchronous Programming: A model allowing concurrent task execution without blocking.
-
Coroutine: A function using 'async def' that can yield control and be resumed with 'await'.
-
Event Loop: The process that handles the execution of coroutines in asyncio.
-
I/O-bound Task: Tasks that require waiting for external input/output operations.
Examples & Real-Life Applications
See how the concepts apply in real-world scenarios to understand their practical implications.
Examples
-
Using asyncio to run multiple fetch functions concurrently rather than sequentially to save time.
-
Creating a simple TCP server using asyncio that handles incoming client requests.
Memory Aids
Use mnemonics, acronyms, or visual cues to help remember key information more easily.
π΅ Rhymes Time
-
Async allows you to run, while others sit and wait for fun.
π Fascinating Stories
-
Imagine a waiter in a busy restaurant. Instead of standing idle while one table orders, he takes multiple orders and manages them all, just like asyncio manages multiple I/O-bound tasks.
π§ Other Memory Gems
-
Remember 'C-E-N-T': Coroutine, Event loop, Non-blocking I/O, Tasks - these are the heart of async programming.
π― Super Acronyms
Use 'A.I.O' - Async programming, I/O-bound tasks, and Optimized efficiency.
Flash Cards
Review key concepts with flashcards.
Glossary of Terms
Review the Definitions for terms.
-
Term: Asynchronous Programming
Definition:
A programming model that allows tasks to be executed concurrently without waiting for each to finish.
-
Term: Coroutine
Definition:
A special function defined with 'async def' that can pause execution using 'await'.
-
Term: Event Loop
Definition:
The core component in asyncio that schedules and runs all coroutines.
-
Term: I/Obound Tasks
Definition:
Operations primarily dependent on input and output operations, such as file handling or network requests.
-
Term: async/await
Definition:
Keywords in Python used to define coroutines and indicate when to pause execution, respectively.