mv element.io @types __mocks__/ debian docker module_system/ playwright res src test webapp Dockerfile .dockerignore .eslintignore .stylelintrc.cjs babel.config.cjs recorder-worklet-loader.cjs .modernizr.json components.json config.json config.sample.json package.json project.json tsconfig.json tsconfig.module_system.json jest.config.ts playwright.config.ts webpack.config.ts build_config.sample.yaml apps/web/

mkdir apps/web/scripts mv scripts/{cleanup.sh,ci_package.sh,copy-res.ts,deploy.py,package.sh} apps/web/scripts And a couple of gitignore tweaks Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>
2026-02-24 15:43:58 +00:00
parent e7509c92a1
commit 91a3cb03c1
3408 changed files with 28 additions and 32 deletions
@@ -0,0 +1,96 @@
+/*
+Copyright 2024 New Vector Ltd.
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+export type GetIframeFn = () => HTMLIFrameElement | null;
+
+export const DEFAULT_STYLES = {
+    imgSrc: "",
+    imgStyle: null as string | null, // css props
+    style: "",
+    textContent: "",
+};
+
+type DownloadOptions = {
+    blob: Blob;
+    name: string;
+    autoDownload?: boolean;
+    opts?: typeof DEFAULT_STYLES;
+};
+
+// set up the iframe as a singleton so we don't have to figure out destruction of it down the line.
+let managedIframe: HTMLIFrameElement;
+let onLoadPromise: Promise<void>;
+function getManagedIframe(): { iframe: HTMLIFrameElement; onLoadPromise: Promise<void> } {
+    if (managedIframe) return { iframe: managedIframe, onLoadPromise };
+
+    managedIframe = document.createElement("iframe");
+
+    // Need to append the iframe in order for the browser to load it.
+    document.body.appendChild(managedIframe);
+
+    // Dev note: the reassignment warnings are entirely incorrect here.
+
+    managedIframe.style.display = "none";
+
+    // @ts-ignore
+    // noinspection JSConstantReassignment
+    managedIframe.sandbox = "allow-scripts allow-downloads";
+
+    onLoadPromise = new Promise((resolve) => {
+        managedIframe.onload = () => {
+            resolve();
+        };
+        managedIframe.src = "usercontent/"; // XXX: Should come from the skin
+    });
+
+    return { iframe: managedIframe, onLoadPromise };
+}
+
+// TODO: If we decide to keep the download link behaviour, we should bring the style management into here.
+
+/**
+ * Helper to handle safe file downloads. This operates off an iframe for reasons described
+ * by the blob helpers. By default, this will use a hidden iframe to manage the download
+ * through a user content wrapper, but can be given an iframe reference if the caller needs
+ * additional control over the styling/position of the iframe itself.
+ */
+export class FileDownloader {
+    private onLoadPromise?: Promise<void>;
+
+    /**
+     * Creates a new file downloader
+     * @param iframeFn Function to get a pre-configured iframe. Set to null to have the downloader
+     * use a generic, hidden, iframe.
+     */
+    public constructor(private iframeFn?: GetIframeFn) {}
+
+    private get iframe(): HTMLIFrameElement {
+        const iframe = this.iframeFn?.();
+        if (!iframe) {
+            const managed = getManagedIframe();
+            this.onLoadPromise = managed.onLoadPromise;
+            return managed.iframe;
+        }
+        this.onLoadPromise = undefined;
+        return iframe;
+    }
+
+    public async download({ blob, name, autoDownload = true, opts = DEFAULT_STYLES }: DownloadOptions): Promise<void> {
+        const iframe = this.iframe; // get the iframe first just in case we need to await onload
+        if (this.onLoadPromise) await this.onLoadPromise;
+        iframe.contentWindow?.postMessage(
+            {
+                ...opts,
+                blob: blob,
+                download: name,
+                auto: autoDownload,
+            },
+            "*",
+        );
+    }
+}