Add OpenScript.fetch cross-origin network API and docs

src/background.js

@@ -1,5 +1,6 @@
 import { syncUserScripts } from './utils/userScripts.js';
 import { runScriptStorageOperation } from './utils/storage.js';
+import { runScriptFetch } from './utils/fetch.js';
 
 let syncQueue = Promise.resolve();
 const safelySync = async options => {
@@ -30,9 +31,16 @@ chrome.runtime.onMessage.addListener((msg, sender, sendResponse) => {
 });
 
 chrome.runtime.onUserScriptMessage.addListener((msg, sender, sendResponse) => {
-  if (msg?.type !== 'OPEN_SCRIPT_STORAGE') return;
-  runScriptStorageOperation(msg.token, msg.operation, msg.key, msg.value)
-    .then(result => sendResponse({ ok: true, ...result }))
-    .catch(error => sendResponse({ ok: false, error: error.message }));
-  return true;
+  if (msg?.type === 'OPEN_SCRIPT_STORAGE') {
+    runScriptStorageOperation(msg.token, msg.operation, msg.key, msg.value)
+      .then(result => sendResponse({ ok: true, ...result }))
+      .catch(error => sendResponse({ ok: false, error: error.message }));
+    return true;
+  }
+  if (msg?.type === 'OPEN_SCRIPT_FETCH') {
+    runScriptFetch(msg.url, msg.options)
+      .then(result => sendResponse({ ok: true, ...result }))
+      .catch(error => sendResponse({ ok: false, error: error.message }));
+    return true;
+  }
 });

src/utils/fetch.js

@@ -0,0 +1,9 @@
+const NULL_BODY_STATUSES = new Set([101, 204, 205, 304]);
+
+export const runScriptFetch = async (url, options = {}) => {
+  const res = await fetch(url, options);
+  const { status, statusText } = res;
+  const headers = [...res.headers.entries()];
+  const body = NULL_BODY_STATUSES.has(status) ? null : await res.arrayBuffer();
+  return { status, statusText, headers, url: res.url, body };
+};

src/utils/userScripts.js

@@ -3,6 +3,7 @@ import { normalizeMatch, parseMeta, getMetaRunAt } from './parser.js';
 import { VERSION } from '../version.js';
 
 const STORAGE_MESSAGE = 'OPEN_SCRIPT_STORAGE';
+const FETCH_MESSAGE = 'OPEN_SCRIPT_FETCH';
 
 export const isUserScriptsAvailable = async () => {
   if (!chrome.userScripts) return false;
@@ -34,7 +35,21 @@ ${code}
     delete: key => call('delete', key).then(() => undefined),
     list: () => call('list').then(result => result.keys),
   });
-  const OpenScript = Object.freeze({ version: '${VERSION}', env, storage });
+  const fetch = async (url, options = {}) => {
+    let { headers, body, ...rest } = options;
+    if (headers instanceof Headers) headers = Object.fromEntries(headers.entries());
+    const response = await chrome.runtime.sendMessage({
+      type: '${FETCH_MESSAGE}', url: url.toString(), options: { ...rest, headers, body },
+    });
+    if (!response?.ok) throw new TypeError(response?.error || 'OpenScript fetch failed');
+    const resBody = [101, 204, 205, 304].includes(response.status) ? null : response.body;
+    const res = new Response(resBody, {
+      status: response.status, statusText: response.statusText, headers: response.headers,
+    });
+    Object.defineProperty(res, 'url', { value: response.url || url.toString() });
+    return res;
+  };
+  const OpenScript = Object.freeze({ version: '${VERSION}', env, storage, fetch });
   globalThis.OpenScript = OpenScript;
   globalThis.env = env;
   return [OpenScript, env];

src/version.js

@@ -1 +1 @@
-export const VERSION = '1.0.3';
+export const VERSION = '1.0.4';