feat: add file proxy for private repos

Author: RyKilleen

src/handler.ts

@@ -13,13 +13,19 @@ declare global {
   const GITHUB_TOKEN: string
 }
 
+const SendJSON = (data: Record<string, unknown>) => {
+  return new Response(JSON.stringify(data), {
+    headers: { 'Content-Type': 'application/json; charset=utf-8' },
+  })
+}
+
 const responses = {
   NotFound: () => new Response('Not found', { status: 404 }),
   NoContent: () => new Response(null, { status: 204 }),
   SendUpdate: (data: TauriUpdateResponse) =>
-    new Response(JSON.stringify(data), {
-      headers: { 'Content-Type': 'application/json; charset=utf-8' },
-    }),
+    SendJSON(data),
+  SendJSON
+
 }
 
 type RequestPathParts = [
@@ -60,8 +66,10 @@ const handleV1Request = async (request: Request) => {
   }
 
   const signature = await findAssetSignature(match.name, release.assets)
+  const proxy = GITHUB_TOKEN?.length;
+  const downloadURL = proxy ? createProxiedFileUrl(match.browser_download_url, request) : match.browser_download_url
   const data: TauriUpdateResponse = {
-    url: match.browser_download_url,
+    url: downloadURL,
     version: remoteVersion,
     notes: release.body,
     pub_date: release.published_at,
@@ -71,8 +79,45 @@ const handleV1Request = async (request: Request) => {
   return responses.SendUpdate(data)
 }
 
+const createProxiedFileUrl = (downloadURL: string, request: Request) => {
+
+  const fileName = downloadURL.split('/')?.at(-1)
+  if (!fileName) { throw new Error('Could not get file name from download URL') }
+
+
+  const path = new URL(request.url)
+  const root = `${path.protocol}//${path.host}`
+
+  return new URL(`/latest/${fileName}`, root).toString()
+}
+
+const getLatestAssets = async (request: Request) => {
+  const fileName = request.url.split('/')?.at(-1)
+  if (!fileName) { throw new Error('Could not get file name from download URL') }
+
+  const release = await getLatestRelease(request)
+  const downloadPath = release.assets.find(({ name }) => name === fileName)?.browser_download_url
+
+  if (!downloadPath) { throw new Error('Could not get file path from download URL') }
+
+  const { readable, writable } = new TransformStream();
+  const file_response = await fetch(downloadPath, {
+    method: 'GET',
+    redirect: 'follow'
+  })
+
+  file_response?.body?.pipeTo(writable);
+  return new Response(readable, file_response);
+
+}
+
 export async function handleRequest(request: Request): Promise<Response> {
   const path = new URL(request.url).pathname
+
+
+  if (path.includes('/latest')) {
+    return getLatestAssets(request)
+  }
   const version = path.slice(1).split('/')[0]
 
   if (version.includes('v')) {