##// END OF EJS Templates
corrected tear down logic handling in observables. Added support for observable query results
corrected tear down logic handling in observables. Added support for observable query results

File last commit:

r109:4a375b9c654a default
r110:1a190b3a757d v1.4.0 default
Show More
dom-inject.ts
100 lines | 2.7 KiB | video/mp2t | TypeScriptLexer
import { id as mid } from "module";
import { TraceSource } from "@implab/core-amd/log/TraceSource";
import { MapOf } from "@implab/core-amd/interfaces";
import { mixin } from "@implab/core-amd/safe";
const trace = TraceSource.get(mid);
function on<T extends keyof HTMLElementEventMap>(node: HTMLElement, eventName: T, handler: (this: HTMLElement, ev: HTMLElementEventMap[T]) => unknown): () => void {
// Add an event listener to a DOM node
node.addEventListener(eventName, handler, false);
return () => node.removeEventListener(eventName, handler, false);
}
interface NodeLoadResult {
node: HTMLElement;
}
class DomInject {
injectionPoint?: HTMLElement;
injectAfter?: HTMLElement;
_map: MapOf<Promise<NodeLoadResult>> = {};
_inject<T extends keyof HTMLElementTagNameMap>(name: T, attr: Partial<HTMLElementTagNameMap[T]>) {
const node = document.createElement(name);
return new Promise<NodeLoadResult>((ok, fail) => {
const cleanup = () => {
noerr();
noload();
};
const noload = on(node, "load", () => {
ok({ node });
cleanup();
});
const noerr = on(node, "error", e => {
fail({
error: e,
node
});
cleanup();
});
mixin(node, attr);
const _injectionPoint = this.injectionPoint || document.head;
const _injectBefore = this.injectAfter ? this.injectAfter.nextSibling : null;
_injectionPoint.insertBefore(node, _injectBefore);
});
}
async injectScript(url: string) {
let d = this._map[url];
if (d === undefined) {
trace.log("js {0}", url);
d = this._inject("script", {
type: "text/javascript",
charset: "utf-8",
src: url
});
this._map[url] = d;
}
try {
await d;
trace.log("done {0}", url);
} catch (e) {
trace.error("failed {0}: {1}", url, e);
throw e;
}
}
async injectStylesheet(url: string) {
let d = this._map[url];
if (d === undefined) {
trace.log("js {0}", url);
d = this._inject("link", {
type: "text/css",
rel: "stylesheet",
href: url
});
this._map[url] = d;
}
try {
await d;
trace.log("done {0}", url);
} catch (e) {
trace.error("failed {0}: {1}", url, e);
throw e;
}
}
}
const instance = new DomInject();
export default instance;