Unleash the power!

slide: https://hackmd.io/p/template-Talk-slide

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We have a collaborative session

please prepare laptop or smartphone to join!

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Who am I?

• Front-end developer
• VSCode :heart:
• I use tabs. :cat:

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70% of our users are developers. Developers :heart: GitHub.

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{%youtube E8Nj7RwXf0s %}

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Usage flow

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digraph {
  compound=true
  rankdir=RL

  graph [ fontname="Source Sans Pro", fontsize=20 ];
  node [ fontname="Source Sans Pro", fontsize=18];
  edge [ fontname="Source Sans Pro", fontsize=12 ];


  subgraph core {
    c [label="Hackmd-it \ncore"] [shape=box]
  }

  c -> sync [ltail=session lhead=session]

  subgraph cluster1 {
     concentrate=true
    a [label="Text source\nGithub, Gitlab, ..."] [shape=box]
    b [label="HackMD Editor"] [shape=box]
    sync [label="sync" shape=plaintext ]
    b -> sync  [dir="both"]
    sync -> a [dir="both"]
    label="An edit session"
  }
}

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Architecture of extension

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Content script

• Bind with each page
• Manipulate DOM
• Add event listeners
• Isolated JavaScript environment
  • It doesn't break things

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:fork_and_knife:

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• onMessage('event'): Register event listener
• sendMessage('event'): Trigger event

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:bulb:

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• Dead simple API
• Only cares about application logic

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import * as Channeru from 'channeru'

// setup channel in different page environment, once
const channel = Channeru.create()

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// in background script
const fakeLogin = async () => true

channel.answer('isLogin', async () => {
  return await fakeLogin()
})

// in inject script
const isLogin = await channel.callBackground('isLogin')
console.log(isLogin) //-> true

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:100: :muscle: :tada:

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Wrap up

• Cross envornment commnication
• A small library to solve messaging pain
• TypeScript Rocks :tada:

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Thank you! :sheep:

You can find me on

• GitHub
• Twitter
• or email me