feat: download purely using octokit

In my understanding octokit automatically uses authentication, but the
real download was done using fetch directly, hence without
authentication.

This approach now uses octokit's getReleaseAsset() to download the
asset, which should use proper authentication, hence allowing
potentially higher rate limits.

Closes: #419

Author: klaernie

src/index.ts

@@ -9,9 +9,9 @@ import { downloadBinary, findRelease } from "./release"
 async function main() {
   if (!(await isReady())) {
     try {
-      const [name, assets] = await findRelease(VERSION)
+      const [name, asset_id, asset_filetype] = await findRelease(VERSION)
       console.info(`Downloading ${name}`)
-      await downloadBinary(assets.browser_download_url)
+      await downloadBinary(asset_id, asset_filetype)
     } catch (e) {
       console.error(`Failed to download binary:\n${e}`)
       await fs.rm(COMBINED_PATH, { recursive: true })

src/release.ts

@@ -1,7 +1,8 @@
-import { writeFile } from "node:fs/promises"
 import os from "node:os"
 
 import { Octokit } from "@octokit/rest"
+import { createWriteStream } from "node:fs";
+import { pipeline } from "node:stream/promises";
 import { getProxyForUrl } from "proxy-from-env"
 import { fetch, ProxyAgent } from "undici"
 import type { RequestInit } from "undici"
@@ -24,15 +25,29 @@ export async function findRelease(version: string) {
   if (!matchedAsset) {
     throw new Error(`The binary '${releasePrefix}*' not found`)
   }
-  return [release.data.name, matchedAsset] as const
+  return [release.data.name, matchedAsset.id, matchedAsset.name.endsWith(".zip") ? "zip" : "tar" ] as const
 }
 
-export async function downloadBinary(url: string) {
-  const response = await proxiedFetch(url)
+export async function downloadBinary(asset_id: number, asset_filetype: string) {
+  // downloading the asset is copied from https://github.com/octokit/rest.js/issues/12#issuecomment-1916023479
+  const asset = await octokit.repos.getReleaseAsset({
+    owner: NAME,
+    repo: NAME,
+    asset_id: asset_id,
+    headers: {
+      accept: "application/octet-stream"
+    },
+    request: {
+      parseSuccessResponseBody: false, // required to access response as stream
+    }
+  });
   const tmpfile = await tmp.file()
-  await writeFile(tmpfile.path, Buffer.from(await response.arrayBuffer()))
 
-  if (url.endsWith(".zip")) {
+  const assetStream = asset.data as unknown as NodeJS.ReadableStream;
+  const outputFile = createWriteStream(tmpfile.path);
+  await pipeline(assetStream, outputFile);
+
+  if (asset_filetype === ".zip") {
     const zip = new admzip(tmpfile.path)
     zip.extractAllTo(COMBINED_PATH, true)
   } else {