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Andrew (he/him)
Andrew (he/him)

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Playing around with browser cookies in Scala.js

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I spent this weekend playing around with Scala.js and learning how to manipulate browser cookies with it.

Check out the live demo at cookies.awwsmm.com.

The source is available at github.com/awwsmm/CookiesScalaJS.

There are a few cool Scala flairs here, particularly this bit which pattern matches on a regular expression

 def clearAllCookies(): Unit = { val Cookie = "([^=]+)=.+".r document.cookie.split("; ").foreach { case Cookie(key) => clearCookie(key) case other => err.println(s"Couldn't parse '$other' as a key=value cookie pair") } } 
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In order to ensure that users don't include the ; or = characters in their cookie keys and values (which confuses the parser), I've also added these two little safeguards, as well

 // prevent the user from typing ';' or '=' into the input input.addEventListener("keypress", (e: dom.KeyboardEvent) => { if (e.key == ";" || e.key == "=") { e.preventDefault() } }) // prevent the user from pasting ';' or '=' into the input input.addEventListener("paste", (e: dom.ClipboardEvent) => { val text = e.clipboardData.getData("text") if (text.contains(";") || text.contains("=")) { e.preventDefault() } }) 
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What do you think? Anyone else on DEV doing anything cool with Scala.js?

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