the cleanup

lib/springProxy.ts

@@ -0,0 +1,68 @@
+import { NextResponse } from "next/server";
+
+const SPRING_BASE =
+    process.env.SPRING_BASE_URL ?? "http://battlbuilder-api:8080";
+
+function forwardHeaders(req: Request) {
+    const headers = new Headers();
+    const auth = req.headers.get("authorization");
+    const cookie = req.headers.get("cookie");
+
+    if (auth) headers.set("authorization", auth);
+    if (cookie) headers.set("cookie", cookie);
+
+    headers.set("accept", "application/json");
+    return headers;
+}
+
+type SpringProxyOptions<TBody> = {
+    method?: "GET" | "POST" | "PUT" | "PATCH" | "DELETE";
+    body?: TBody;
+    cache?: RequestCache;
+};
+
+export async function springProxy<TResponse, TBody = never>(
+    req: Request,
+    path: string,
+    options?: SpringProxyOptions<TBody>
+) {
+    const url = `${SPRING_BASE}${path}`;
+    const headers = forwardHeaders(req);
+
+    const init: RequestInit = {
+        method: options?.method ?? "GET",
+        headers,
+        cache: options?.cache ?? "no-store",
+    };
+
+    if (options && "body" in options && options.body !== undefined) {
+        headers.set("content-type", "application/json");
+        init.body = JSON.stringify(options.body);
+    }
+
+    const res = await fetch(url, init);
+
+    // If Spring returns 204 No Content, don't try to parse JSON
+    if (res.status === 204) {
+        return new NextResponse(null, { status: 204 });
+    }
+
+    const contentType = res.headers.get("content-type") ?? "";
+    let payload: unknown;
+
+    if (contentType.includes("application/json")) {
+        payload = await res.json().catch(() => null);
+    } else {
+        payload = await res.text().catch(() => null);
+    }
+
+    // If Spring returned JSON, we respond JSON; otherwise text
+    if (typeof payload === "string") {
+        return new NextResponse(payload, {
+            status: res.status,
+            headers: { "content-type": contentType || "text/plain" },
+        });
+    }
+
+    return NextResponse.json(payload as TResponse, { status: res.status });
+}