Always fall back to anonymous download (#304)

Closes: #268
Closes: #305

src/utils/octokit.ts

@@ -0,0 +1,58 @@
+import { Octokit as Core } from "@octokit/core";
+import type {
+  Constructor,
+  OctokitOptions,
+} from "@octokit/core/dist-types/types";
+import {
+  paginateRest,
+  type PaginateInterface,
+} from "@octokit/plugin-paginate-rest";
+import { legacyRestEndpointMethods } from "@octokit/plugin-rest-endpoint-methods";
+import { fetch as undiciFetch, ProxyAgent, type RequestInit } from "undici";
+
+export type { RestEndpointMethodTypes } from "@octokit/plugin-rest-endpoint-methods";
+
+const DEFAULTS = {
+  baseUrl: "https://api.github.com",
+  userAgent: "setup-uv",
+};
+
+export function getProxyAgent() {
+  const httpProxy = process.env.HTTP_PROXY || process.env.http_prox;
+  if (httpProxy) {
+    return new ProxyAgent(httpProxy);
+  }
+
+  const httpsProxy = process.env.HTTPS_PROXY || process.env.https_proxy;
+  if (httpsProxy) {
+    return new ProxyAgent(httpsProxy);
+  }
+
+  return undefined;
+}
+
+export const customFetch = async (url: string, opts: RequestInit) =>
+  await undiciFetch(url, {
+    dispatcher: getProxyAgent(),
+    ...opts,
+  });
+
+export const Octokit: typeof Core &
+  Constructor<
+    {
+      paginate: PaginateInterface;
+    } & ReturnType<typeof legacyRestEndpointMethods>
+  > = Core.plugin(paginateRest, legacyRestEndpointMethods).defaults(
+  function buildDefaults(options: OctokitOptions): OctokitOptions {
+    return {
+      ...DEFAULTS,
+      ...options,
+      request: {
+        fetch: customFetch,
+        ...options.request,
+      },
+    };
+  },
+);
+
+export type Octokit = InstanceType<typeof Octokit>;