Archive snapshots of websites locally (#672)

* Add basic HTML snapshots

* Implement asset list

* Add snapshot creation tests

* Add deletion tests

* Show file size

* Remove snapshots

* Create new snapshots

* Switch to single-file

* CSS tweak

* Remove auto refresh

* Show delete link when there is no file yet

* Add current date to display name

* Add flag for snapshot support

* Add option for disabling automatic snapshots

* Make snapshots sharable

* Document image variants

* Update README.md

* Add migrations

* Fix tests

bookmarks/frontend/behaviors/form.js

@@ -0,0 +1,54 @@
+import { registerBehavior, swap } from "./index";
+
+class FormBehavior {
+  constructor(element) {
+    this.element = element;
+    element.addEventListener("submit", this.onFormSubmit.bind(this));
+  }
+
+  async onFormSubmit(event) {
+    event.preventDefault();
+
+    const url = this.element.action;
+    const formData = new FormData(this.element);
+    if (event.submitter) {
+      formData.append(event.submitter.name, event.submitter.value);
+    }
+
+    await fetch(url, {
+      method: "POST",
+      body: formData,
+      redirect: "manual", // ignore redirect
+    });
+
+    // Dispatch refresh events
+    const refreshEvents = this.element.getAttribute("refresh-events");
+    if (refreshEvents) {
+      refreshEvents.split(",").forEach((eventName) => {
+        document.dispatchEvent(new CustomEvent(eventName));
+      });
+    }
+
+    // Refresh form
+    await this.refresh();
+  }
+
+  async refresh() {
+    const refreshUrl = this.element.getAttribute("refresh-url");
+    const html = await fetch(refreshUrl).then((response) => response.text());
+    swap(this.element, html);
+  }
+}
+
+class FormAutoSubmitBehavior {
+  constructor(element) {
+    this.element = element;
+    this.element.addEventListener("change", () => {
+      const form = this.element.closest("form");
+      form.dispatchEvent(new Event("submit", { cancelable: true }));
+    });
+  }
+}
+
+registerBehavior("ld-form", FormBehavior);
+registerBehavior("ld-form-auto-submit", FormAutoSubmitBehavior);