0
Fork 0
mirror of https://github.com/withastro/astro.git synced 2024-12-16 21:46:22 -05:00
astro/packages/integrations/lit/server.js
Fred K. Schott 6386c14d00
Astro Integration System (#2820)
* update examples

* add initial integrations

* update tests

* update astro

* update ci

* get final tests working

* update injectelement todo

* update ben code review

* respond to final code review feedback
2022-03-18 15:35:45 -07:00

72 lines
1.8 KiB
JavaScript
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import './server-shim.js';
import '@lit-labs/ssr/lib/render-lit-html.js';
import { LitElementRenderer } from '@lit-labs/ssr/lib/lit-element-renderer.js';
function isCustomElementTag(name) {
return typeof name === 'string' && /-/.test(name);
}
function getCustomElementConstructor(name) {
if (typeof customElements !== 'undefined' && isCustomElementTag(name)) {
return customElements.get(name) || null;
}
return null;
}
async function isLitElement(Component) {
const Ctr = getCustomElementConstructor(Component);
return !!(Ctr && Ctr._$litElement$);
}
async function check(Component, _props, _children) {
// Lit doesn't support getting a tagName from a Constructor at this time.
// So this must be a string at the moment.
return !!(await isLitElement(Component));
}
function* render(tagName, attrs, children) {
const instance = new LitElementRenderer(tagName);
// LitElementRenderer creates a new element instance, so copy over.
const Ctr = getCustomElementConstructor(tagName);
for (let [name, value] of Object.entries(attrs)) {
// check if this is a reactive property
if (name in Ctr.prototype) {
instance.setProperty(name, value);
} else {
instance.setAttribute(name, value);
}
}
instance.connectedCallback();
yield `<${tagName}`;
yield* instance.renderAttributes();
yield `>`;
const shadowContents = instance.renderShadow({});
if (shadowContents !== undefined) {
yield '<template shadowroot="open">';
yield* shadowContents;
yield '</template>';
}
yield children || ''; // dont print “undefined” as string
yield `</${tagName}>`;
}
async function renderToStaticMarkup(Component, props, children) {
let tagName = Component;
let out = '';
for (let chunk of render(tagName, props, children)) {
out += chunk;
}
return {
html: out,
};
}
export default {
check,
renderToStaticMarkup,
};