©OVERDUEBOOK Python 3.6 Release Party ~asynchronous related~ 2017-01-31 Tue. Tetsuya Morimoto

INTRODUCTION ৿ຊ఩໵ (@t2y) ϙʔλϧαΠτͷձࣾ ੲ͸αʔόʔαΠυΤϯδχΞ ࠓ͸ΠϯϑϥΤϯδχΞݟश͍ new! ͓࢓ࣄͰ͸ओʹ Go ॻ͍͍ͯΔ͚ͲɺPython ΋࢖͍·͢ ࠷ۙ΍ͬͨ͜ͱ [຋༁]αΠτ৴པੑΤϯδχΞϦϯά (SRE) ͱ͸Կ͔ʁ

AGENDA ඇಉظʗฒߦॲཧͷഎܠ Python 3 ͷඇಉظॲཧͷมભ asyncio ϞδϡʔϧΛ࢖ͬͯΈΑ͏ Python 3.6 ͷඇಉظॲཧͷ৽ػೳ (PEP-525/530) asyncio ͷ՝୊ʁ ·ͱΊ

ATTENTION ͜͜Ͱ঺հ͢Δࢿྉ΋ίʔυ΋ެ։͠·͢ ࢲ͕ asyncio ΍ؔ࿈ٕज़ʹૄ͍ͨΊɺҰੜݒ໋ௐ΂ͨ͜ͱΛ ·ͱΊͨͭ΋ΓͰ͕͢ɺؒҧ͍ͬͯͨΒ͝ΊΜͳ͍͞

ඇಉظʗฒߦॲཧͷഎܠ

ASYNCHRONOUS APPROACH ϚϧνεϨου vs. Πϕϯτۦಈ ෼͔Γ΍͍͢ൺֱ Apache vs. Nginx Java (JVM) vs. Node.js ͲͪΒ͕ྑ͍ͱ͍͏Θ͚Ͱ͸ͳ͘Ξϓϩʔνͷҧ͍ ΞϓϦέʔγϣϯͷಛੑʹΑͬͯ޲͖ෆ޲͖͸͋Δʁ ࠓ೔ͷ࿩୊͸ͬͪ͜

CONCURRENT & PARALLEL ฒߦ (concurrent) ͱฒྻ (parallel) ݫີͳఆٛ͸ͳ͍ Rob Pike ࢯͷߨԋʹΑΔͱɺ͜ΜͳΠϝʔδˣ ࠓ೔ͷ࿩୊͸ͬͪ͜

EXECUTABLE PROGRAM ࣮ߦϓϩάϥϜͷॲཧͷ෼ׂ୯Ґ ϓϩηε (Process) OS ͕؅ཧɺಠࣗͷϝϞϦۭؒ (ωΠςΟϒ)εϨου (Thread) OS ͕؅ཧɺಉҰϓϩηε಺ͰϝϞϦۭؒΛڞ༗ ίϧʔνϯ (Coroutine) ≒ ϑΝΠόʔʗδΣωϨʔλʔ (ػೳతʹ͸ಉ͡) ॲཧΛ్தͰҰ࣌தஅͨ͠Γɺ్த͔Β෮ݩͨ͠Γ͠ͳ͕Β࣮ߦͰ͖Δ ݴޠ (ΞϓϦ) ͕؅ཧ ϓϩηε1 εϨου1 εϨου2 ϓϩηε2

SEMANTICS IN PYTHON 3 δΣωϨʔλʔ yield, yield from Λ࢖ͬͯఆٛͨؔ͠਺ ίϧʔνϯ ωΠςΟϒίϧʔνϯ (native coroutine) async def ߏจͰ࣮૷͞ΕΔ δΣωϨʔλʔϕʔεͷίϧʔνϯ (generator-based coroutine) δΣωϨʔλʔߏจͰ࣮૷͞ΕΔ ίϧʔνϯؔ਺ ίϧʔνϯΦϒδΣΫτΛฦؔ͢਺ɺasync ߏจΛ࢖͏

PYTHON 3 ͷඇಉظॲཧͷมભ

HISTORY (1) 3.3 yield from ߏจ δΣωϨʔλʔ಺෦ͰαϒδΣωϨʔλʔ΁ͷҠৡ PEP 380 -- Syntax for Delegating to a Subgenerator 3.4 asyncio ϞδϡʔϧΛඪ४ϥΠϒϥϦ΁ (࢑ఆ) ඇಉظʗฒߦॲཧΛ࣮૷͢ΔͨΊͷΠϯϑϥ PEP 3156 -- Asynchronous IO Support Rebooted: the "asyncio" Module

HISTORY (2) 3.5 async ߏจͱ await ࣜ ωΠςΟϒίϧʔνϯΛಋೖ PEP 492 -- Coroutines with async and await syntax 3.6 asyncio Ϟδϡʔϧͷ API ͕࢑ఆ → ҆ఆ΁ ඇಉظδΣωϨʔλʔͱඇಉظ಺แදهΛಋೖ PEP 525 -- Asynchronous Generators PEP 530 -- Asynchronous Comprehensions new! ࠓ೔ͷ࿩୊͸͜͜

ASYNCIO ϞδϡʔϧΛ࢖͏

USE CASE ίϧʔνϯͬͯͲ͏͍͏ͱ͖ʹ࢖͏ͷʁ ڠௐతϚϧνλεΫɺྫ֎ɺΠϕϯτϧʔϓɺΠςϨʔ λʔɺແݶϦετɺύΠϓͱ͍ͬͨॲཧΛ࣮૷͢Δͱ͖ ར༻ྫ ঢ়ଶϚγϯ ΞΫλʔϞσϧ CSP (Communicating Sequential Processes)

SAMPLE CODE Producer-Consumerύλʔϯ Λ࣮૷ͯ͠ΈΔ ੜ࢈ऀ (Producer): 3ਓɺ৯΂΋ͷΛςʔϒϧʹஔ͘ ফඅऀ (Consumer): 3ਓɺςʔϒϧʹ͋Δ΋ͷΛ৯΂Δ ςʔϒϧ: ৯΂΋ͷΛஔ͘৔ॴɺ1͔ͭ͠ஔ͚ͳ͍ e.g.) producer_consumer_pattern_generator_based_coroutine.py producer_consumer_pattern_native_coroutine.py

PYTHON 3.6 ͷඇಉظॲཧͷ৽ػೳ (PEP-525/530)

ඇಉظδΣωϨʔλʔ (PEP-525) ඇಉظδΣωϨʔλʔΛ yield Λ࢖ͬͯఆٛͰ͖Δ ͜Ε·ͰͷδΣωϨʔλʔΛఆٛ͢Δͷͱಉ͡ײ֮ ͓खܰɺ׌ͭ2ഒ଎͍ e.g.) async_iter_ticker.py async_for_example_pep492.py async_for_example_pep525.py

ඇಉظ಺แදه (PEP 530) ඇಉظ಺แදهͷهड़ set: {await afun(i) async for i in agen()} list: [await afun(i) async for i in agen()] dict: {i: await afun(i ** 2) async for i in agen()} generator: (await afun(i ** 2) async for i in agen()) ͜ΕΒ͸ async def Ͱఆٛ͞Εͨؔ਺಺ͰͷΈར༻Ͱ͖Δ ඇಉظδΣωϨʔλʔࣜ͸ 3.7 ͰͲ͜Ͱ΋࢖͑ΔΑ͏ʹͳΔ e.g.) async_comprehension_example.py

ASYNCIO ͷ՝୊ʁ

ARMIN RONACHER’S BLOG I don’t understand Python’s Asyncio ͱ͍͏ϒϩάهࣄ twisted ͔Β֓೦ΛऔΓೖΕ͍ͯΔʁ δΣωϨʔλʔͷઃܭϛε e.g.) surprising_generator.py ෳ਺ͷΠϕϯτϧʔϓΛෳ਺εϨουͰѻ͏ͱ͖ʹ໌ࣔతͱ͸ݴ͑ͳ͍Ͷ ΠϕϯτϧʔϓͰ subprocess Λ࣮ߦͯͦ͠ͷγάφϧΛัଊͯ͠ dispatch ͢Δͱ͔ ϩʔΧϧσʔλΛѻ͏ context ͷ֓೦͕ͳ͍ΑͶ ͦ΋ͦ΋ asyncio ʹ context ͷ֓೦͕ͳ͍ asyncio ͷ࠷ѱͳͱ͜Ζ͸େͯ͠଎͘ͳ͍ David Beazley ࢯͷ curio ͸ asyncio ΑΓ75-150% ΄Ͳ଎͍ https://github.com/dabeaz/curio

JINJA 2.9 RELEASE Jinja 2.9 Released Python 3 Feature Support ͜ͷ࣮૷Λ͍ͯͯ͠ϒϩάΛॻ͍ͨΜͩͱࢥ͏ jinja2 Ͱ async/await Λϑϧαϙʔτ ςϯϓϨʔτΤϯδϯʹ coroutine function Λ౉ͤΔ

·ͱΊ

SUMMARY ඇಉظʗฒߦॲཧͷ͜ͱ ຊ࣭తʹ೉͍͠ॲཧͷ1ͭ ݴޠॲཧܥ͕ϓϩάϥϚʔΛαϙʔτ: async/await Python 3 ʹ͔͠ͳ͍৽ػೳ 2→3 ҠߦΛଅ͢ຊ໋ʁ (≠ ϓϩύΨϯμ) 3.6 Ͱػೳ͕Ұஈམʁ asyncio Ϟδϡʔϧͷ API ͕҆ఆ൛΁ ඇಉظδΣωϨʔλʔ

REFERENCE ൃදͰ঺հͨ͠αϯϓϧίʔυ https://github.com/t2y/python-study/tree/master/ Python36ReleaseParty/async ϚϧνίΞ࣌୅ͷ࠷৽ฒྻฒߦٕज़ Overview of Modern Concurrency and Parallelism Concepts 18.5. asyncio — Asynchronous I/O, event loop, coroutines and tasks pymotw3: asyncio — Asynchronous I/O, event loop, and concurrency tools