Access html5 data-* attributes defined in a module script

Question

When loading scripts without using modules, I could use the document.currentscript to access custom attributes.

Eg

<script src="js/myscript.js" data-custom-attribute="my-value"></script>

Within myscript.js I can then do the following

// will contain "my-value"
const myAttribute = document.currentScript.getAttribute('data-custom-attribute'); 

If I load the javascript using module syntax however, the currentScript is set to null and this doesn't work.

<script src="js/myscript.js" data-custom-attribute="my-value" type="module"></script>

Is there a way to still access such attributes within the javascript file?

Answer 1

From MDN

The Document.currentScript property returns the element whose script is currently being processed and isn't a JavaScript module . (For modules use import.meta instead.)

import.meta does not provide the data-attribute. Here are a few alternatives:

[ edit may 2022 ] The import from the original snippet does not exist anymore. Though it's still loaded from cdn.jsdelivr.net , this may in the future not be the case. So, added a new snippet using a more persistent library .

 <script data-custom-attribute="my-value" type="module"> import {Logger} from "https://cdn.jsdelivr.net/gh/KooiInc/DOM-Utilities@v1.1.2/SmallHelpers.js"; const log = Logger(); log(`document.currentScript is ${document.currentScript}`); log(`But with querySelector... data-custom-attribute from module script: ${ document.querySelector("script[type=module]").dataset.customAttribute}`); log(`Or more precize: document.querySelector("script[data-custom-attribute]"): ${ document.querySelector("script[data-custom-attribute]").dataset.customAttribute}`); log(`Or retrieve and filter document.scripts: ${[...document.scripts].find(scrpt => scrpt.dataset.customAttribute).dataset.customAttribute}`); </script>

 <script type="module" data-custom-attribute="my-value"> import $ from "https://kooiinc.github.io/JQL/lib/JQLBundle.js"; $.setStyle(`#result`, {whiteSpace: `nowrap`}); $.setStyle(`#result div`, {marginTop: `0.3rem`}); $.setStyle(`code`, {color: `green`}); const log = (...lines) => lines.forEach( line => $(`#result`).html(`<div>${line}</div>`, true)); const indent = `<br>&nbsp;&nbsp;`; // -------------------------------------------------------------------------- log(`<code>document.currentScript</code> = ${document.currentScript}`); log(`But<br> <code>document.querySelector("script[type=module]").dataset.customAttribute</code> = "${ document.querySelector("script[type=module]").dataset.customAttribute}"`); log(`Or targeted exactly<br> <code>document.querySelector("script[data-custom-attribute]") ${indent}.dataset.customAttribute</code> = "${ document.querySelector("script[data-custom-attribute]").dataset.customAttribute}"`); log(`Or retrieve from <code>document.scripts</code><br> <code>[...document.scripts].find(scrpt => ${indent}scrpt.dataset.customAttribute).dataset.customAttribute</code> = "${ [...document.scripts].find(scrpt => scrpt.dataset.customAttribute).dataset.customAttribute}"`); </script> <div id="result"></result>

Answer 2

I don't have a solution to this problem, but I wanted to point out that there can also be a problem with non module scripts not showing document.currentScript.getAttribute(...) . The problem may be specific to Firefox. Reference .