AsyncIO

AsyncIO do eventloop à interface

Apresentado por @drgarcia1986 e @renanivo

Transcript

1. AsyncIO
2. Sockets
3. "...a socket is the interface between the application layer and the transport layer within a host. It is also referred to as the Application Programming Interface (API) between the application and the network, since the socket is the programming interface with which network applications are built" — Kurose, Computer Networking A Top-Down Approach
4. Echo Client
6. Echo Server
8. I/O Multiplexing
9. "What we need is the capability to tell the kernel that we want to be notified if one or more I/O conditions are ready (i.e., input is ready to be read, or the descriptor is capable of taking more output). This capability is called I/O multiplexing" — Stevens, Unix Networking Programming Volume 1
10. Server não blocante usando Select
11. "select function: This function allows the process to instruct the kernel to wait for any one of multiple events to occur and to wake up the process only when one or more of these events occurs or when a specified amount of time has passed." — Stevens, Unix Networking Programming Volume 1
15. Server não blocante usando Epoll
16. "The epoll API [...]: monitoring multiple file descriptors to see if I/O is possible on any of them. The epoll API [...] scales well to large numbers of watched file descriptors." — man pages, Linux (http://man7.org/linux/man-pages/man7/epoll.7.html)
19. Server não blocante usando Selectors
20. "This module allows high-level and efficient I/O multiplexing, built upon the select module primitives. Users are encouraged to use this module instead, unless they want precise control over the OS-level primitives used." — Docs, Python (https://docs.python.org/3/library/selectors.html)
23. Let's see it in action!
24. Iterators
25. "Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation" — Design Patters, GoF
26. Design Patterns, GoF
28. PEP 234 Iterators • __iter__ • __next__
30. Generators
31. "Generator is a special routine that can be used to control the iteration behaviour of a loop. However, instead of building an array containing all the values and returning them all at once, a generator yields the values one at a time, which requires less memory and allows the caller to get started processing the first few values immediately." — Wikipedia
32. PEP 255 Simple Generators • yield
34. Coroutines
35. "Coroutines are computer-program components that generalize subroutines for non-preemptive multitasking, by allowing multiple entry points for suspending and resuming execution at certain locations." — Wikipedia
36. PEP 342 Coroutines via Enhanced Generators • generator.send() • generator.throw() • generator.close()
38. PEP 380 Syntax for Delegating to a Subgenerator • yield from
40. PEP 492 Coroutines with async and await syntax • native coroutine • @types.coroutine • async with • async for
41. Onde Sockets, Iterators, Generators, Coroutines e Futures se relacionam?
43. Fonte: https://docs.python.org/3/library/asyncio-task.html
48. Obrigado