AN INTRODUCTION
TO SERVICE
WORKERS
JS Monthly London / April 2016
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Phil Nash
@philnash
http:/
/philna.sh
philnash@twilio.com
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AN INTRODUCTION
TO SERVICE
WORKERS
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SERVICE WORKERS
ARE SCRIPTS THAT
INTERCEPT
NETWORK REQUESTS
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SO WEB DEVELOPERS
CAN TREAT THE
NETWORK AS AN
ENHANCEMENT
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AND PROVIDE
OFFLINE
EXPERIENCES FOR
USERS OF WEB
APPLICATIONS
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A SLIGHTLY LONGER
INTRODUCTION TO
SERVICE WORKERS
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XMLHttpRequest
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IN THE FUTURE WE
WILL WONDER HOW
WE COPED WITHOUT
SERVICE WORKERS
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THE BIRTH OF
THE SERVICE
WORKER
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The Application Cache
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“THE APPLICATION CACHE IS A
DOUCHEBAG”
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The Spec
https:/
/slightlyoff.github.io/ServiceWorker/spec/service
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Browsers
40 27 44
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SO WHAT DOES
IT REALLY DO?
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Install it
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Install it
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Install it
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It intercepts network requests
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IT'S A PROXY
THAT YOU
CONTROL
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SECURITY?
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HTTPS
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LOCALHOST
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DEMO
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WHY?
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WEB VS NATIVE
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Native
Web
Online by default Offline by default
Discoverable on the web App store installation
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Native
Web
Offline first Offline by default
Discoverable on the web App store installation
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DON'T CARE
FOR OFFLINE?
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PERFORMANCE
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FALLBACKS
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No content
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THERE'S MORE!
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PUSH
NOTIFICATIONS
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DEMO
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Browsers
42 44
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WITH GREAT
POWER…
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BACKGROUND
SYNC
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DEMO
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Browsers
49
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GEOFENCING
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MAYBE...?
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PROGRESSIVE
WEB APPS
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Progressive Web Apps
• Service Worker (+ HTTPS)
• manifest.json
• User engagement
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APP INSTALL
BANNERS
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No content
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ICON ON
HOMESCREEN
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...
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$$ PROFIT! $$
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SERVICE
WORKERS
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ENHANCEMENT
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IN THE FUTURE WE
WILL WONDER HOW
WE COPED WITHOUT
SERVICE WORKERS
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1:13
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THANKS!
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Use code PNASH20 for 20% off tickets
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Help me!
On a scale of 0 to 10, how likely is it that you
would recommend this talk to a friend or
colleague?
020 3322 5761
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Thanks!
@philnash
http:/
/philna.sh
philnash@twilio.com
On a scale of 0 to 10, how likely is it that you
would recommend this talk to a friend or
colleague?
020 3322 5761