fix fetch error

Author: Ankcorn

src/api/cloudflare.ts

@@ -66,7 +66,8 @@ export class CloudflareApi {
 	private readonly fetcher: typeof fetch;
 
 	constructor(private readonly config: CloudflareApiConfig) {
-		this.fetcher = config.fetcher ?? fetch;
+		// Wrap fetch in arrow function to avoid "Illegal invocation" binding errors in Workers runtime
+		this.fetcher = config.fetcher ?? ((...args) => fetch(...args));
 	}
 
 	private get headers(): HeadersInit {

src/workflow.ts

@@ -48,7 +48,7 @@ export class MetricsExporterWorkflow extends WorkflowEntrypoint<Env> {
 			);
 			const id = jurisdiction.idFromName("metrics-proxy");
 			const stub = jurisdiction.get(id);
-			fetcher = stub.fetch.bind(stub);
+			fetcher = (input, init) => stub.fetch(new Request(input, init));
 		}
 
 		const cloudflare = createCloudflareApi(

test/cloudflare-api.test.ts

@@ -0,0 +1,58 @@
+import { describe, expect, it, vi } from "vitest";
+import { createCloudflareApi } from "../src/api/cloudflare";
+
+describe("CloudflareApi", () => {
+	describe("fetcher binding", () => {
+		it("uses global fetch without binding errors when no custom fetcher provided", async () => {
+			const mockFetch = vi.fn().mockResolvedValue(
+				new Response(
+					JSON.stringify({
+						success: true,
+						result: [],
+					}),
+				),
+			);
+
+			// Temporarily replace global fetch
+			const originalFetch = globalThis.fetch;
+			globalThis.fetch = mockFetch;
+
+			try {
+				const api = createCloudflareApi("test-account", "test-token");
+				await api.listContainers();
+
+				expect(mockFetch).toHaveBeenCalledTimes(1);
+			} finally {
+				globalThis.fetch = originalFetch;
+			}
+		});
+
+		it("uses custom fetcher when provided", async () => {
+			const customFetcher = vi.fn().mockResolvedValue(
+				new Response(
+					JSON.stringify({
+						success: true,
+						result: [],
+					}),
+				),
+			);
+
+			const api = createCloudflareApi(
+				"test-account",
+				"test-token",
+				customFetcher,
+			);
+			await api.listContainers();
+
+			expect(customFetcher).toHaveBeenCalledTimes(1);
+			expect(customFetcher).toHaveBeenCalledWith(
+				"https://api.cloudflare.com/client/v4/accounts/test-account/containers/applications",
+				expect.objectContaining({
+					headers: expect.objectContaining({
+						Authorization: "Bearer test-token",
+					}),
+				}),
+			);
+		});
+	});
+});