Sievepad integration

src/lib/sievepad.test.ts

@@ -0,0 +1,47 @@
+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <[email protected]>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+import { inflateRawSync } from 'node:zlib';
+import { describe, expect, it } from 'vitest';
+
+import { SIEVEPAD_URL, isSieveScriptField, sievepadLink } from './sievepad';
+
+function decode(link: string): unknown {
+  const token = new URLSearchParams(new URL(link).hash.slice(1)).get('w') ?? '';
+  return JSON.parse(inflateRawSync(Buffer.from(token, 'base64url')).toString('utf8'));
+}
+
+describe('sievepadLink', () => {
+  it('encodes the script as a single main entry', async () => {
+    const source = 'require "imap4flags";\r\naddflag "\\\\Seen";\r\n';
+    const link = await sievepadLink('Filters é', source);
+
+    expect(link.startsWith(`${SIEVEPAD_URL}#w=`)).toBe(true);
+    expect(link.slice(`${SIEVEPAD_URL}#w=`.length)).toMatch(/^[A-Za-z0-9_-]+$/);
+    expect(decode(link)).toEqual({
+      v: 1,
+      name: 'Filters é',
+      scripts: [{ name: 'main', source: 'require "imap4flags";\naddflag "\\\\Seen";\n' }],
+      messages: [],
+      settings: {},
+    });
+  });
+
+  it('truncates long workspace names', async () => {
+    const link = await sievepadLink('x'.repeat(200), 'keep;');
+    expect((decode(link) as { name: string }).name).toHaveLength(80);
+  });
+});
+
+describe('isSieveScriptField', () => {
+  it('matches only the known script fields', () => {
+    expect(isSieveScriptField('x:SieveUserScript', 'contents')).toBe(true);
+    expect(isSieveScriptField('x:SieveSystemScript', 'contents')).toBe(true);
+    expect(isSieveScriptField('SieveScript', 'blobId')).toBe(true);
+    expect(isSieveScriptField('SieveScript', 'name')).toBe(false);
+    expect(isSieveScriptField('x:Domain', 'contents')).toBe(false);
+  });
+});

src/lib/sievepad.ts

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+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <[email protected]>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+export const SIEVEPAD_URL = 'https://sievepad.com/';
+
+const SIEVEPAD_FORMAT_VERSION = 1;
+const SIEVEPAD_MAX_NAME_LENGTH = 80;
+const SIEVEPAD_MAIN_SCRIPT = 'main';
+const BASE64_CHUNK_SIZE = 0x8000;
+const WARNING_DISMISSED_KEY = 'stalwart-sievepad-warning-dismissed';
+
+const SIEVE_SCRIPT_FIELDS: Record<string, string> = {
+  'x:SieveSystemScript': 'contents',
+  'x:SieveUserScript': 'contents',
+  SieveScript: 'blobId',
+};
+
+export function isSieveScriptField(objectName: string, fieldName: string): boolean {
+  return SIEVE_SCRIPT_FIELDS[objectName] === fieldName;
+}
+
+function toBase64Url(bytes: Uint8Array): string {
+  let binary = '';
+  for (let i = 0; i < bytes.length; i += BASE64_CHUNK_SIZE) {
+    binary += String.fromCharCode(...bytes.subarray(i, i + BASE64_CHUNK_SIZE));
+  }
+  return btoa(binary).replace(/\+/g, '-').replace(/\//g, '_').replace(/=+$/, '');
+}
+
+export async function sievepadLink(name: string, source: string, base = SIEVEPAD_URL): Promise<string> {
+  const json = JSON.stringify({
+    v: SIEVEPAD_FORMAT_VERSION,
+    name: name.slice(0, SIEVEPAD_MAX_NAME_LENGTH),
+    scripts: [{ name: SIEVEPAD_MAIN_SCRIPT, source: source.replace(/\r\n/g, '\n') }],
+    messages: [],
+    settings: {},
+  });
+  const stream = new Blob([new TextEncoder().encode(json)]).stream().pipeThrough(new CompressionStream('deflate-raw'));
+  const packed = new Uint8Array(await new Response(stream).arrayBuffer());
+  return `${base}#w=${toBase64Url(packed)}`;
+}
+
+export async function openInSievepad(name: string, source: string): Promise<void> {
+  const tab = window.open('about:blank', '_blank');
+  if (tab) tab.opener = null;
+  let link: string;
+  try {
+    link = await sievepadLink(name, source);
+  } catch (err) {
+    tab?.close();
+    throw err;
+  }
+  if (tab) {
+    tab.location.replace(link);
+  } else {
+    window.open(link, '_blank', 'noopener,noreferrer');
+  }
+}
+
+export function isSievepadWarningDismissed(): boolean {
+  try {
+    return localStorage.getItem(WARNING_DISMISSED_KEY) === 'true';
+  } catch {
+    return false;
+  }
+}
+
+export function dismissSievepadWarning(): void {
+  try {
+    localStorage.setItem(WARNING_DISMISSED_KEY, 'true');
+  } catch {
+    return;
+  }
+}