Add Residential Proxy API support

__tests__/ipinfo-resproxy-middleware.test.ts

@@ -0,0 +1,125 @@
+import { Request, Response, NextFunction } from "express";
+import { ipinfoResproxy, originatingIPSelector } from "../src/index";
+import { Resproxy } from "node-ipinfo/dist/src/common";
+
+// Mock the node-ipinfo module
+const mockLookupResproxy = jest.fn();
+jest.mock("node-ipinfo", () => ({
+    IPinfoWrapper: jest.fn().mockImplementation(() => ({
+        lookupResproxy: mockLookupResproxy
+    }))
+}));
+
+describe("ipinfoResproxyMiddleware", () => {
+    const mockToken = "test_token";
+    let mockReq: Partial<Request> & { ipinfo_resproxy?: Resproxy };
+    let mockRes: Partial<Response>;
+    let next: NextFunction;
+
+    beforeEach(() => {
+        // Reset mocks before each test
+        jest.clearAllMocks();
+
+        // Set up default mock response
+        mockLookupResproxy.mockResolvedValue({
+            ip: "175.107.211.204",
+            last_seen: "2026-01-15",
+            percent_days_seen: 100,
+            service: "test_service"
+        });
+
+        // Setup mock request/response
+        mockReq = {
+            ip: "175.107.211.204",
+            headers: { "x-forwarded-for": "5.6.7.8, 10.0.0.1" },
+            header: jest.fn((name: string) => {
+                if (name.toLowerCase() === "set-cookie") {
+                    return ["mock-cookie-1", "mock-cookie-2"];
+                }
+                if (name.toLowerCase() === "x-forwarded-for") {
+                    return "5.6.7.8, 10.0.0.1";
+                }
+                return undefined;
+            }) as jest.MockedFunction<
+                ((name: "set-cookie") => string[] | undefined) &
+                    ((name: string) => string | undefined)
+            >
+        };
+        mockRes = {};
+        next = jest.fn();
+    });
+
+    it("should use defaultIPSelector when no custom selector is provided", async () => {
+        const middleware = ipinfoResproxy({ token: mockToken });
+
+        await middleware(mockReq, mockRes, next);
+
+        expect(mockLookupResproxy).toHaveBeenCalledWith("175.107.211.204");
+        expect(mockReq.ipinfo_resproxy).toEqual({
+            ip: "175.107.211.204",
+            last_seen: "2026-01-15",
+            percent_days_seen: 100,
+            service: "test_service"
+        });
+        expect(next).toHaveBeenCalled();
+    });
+
+    it("should use originatingIPSelector when specified", async () => {
+        mockLookupResproxy.mockResolvedValue({
+            ip: "5.6.7.8",
+            last_seen: "2026-01-15",
+            percent_days_seen: 50,
+            service: "proxy_service"
+        });
+
+        const middleware = ipinfoResproxy({
+            token: mockToken,
+            ipSelector: originatingIPSelector
+        });
+
+        await middleware(mockReq, mockRes, next);
+
+        expect(mockLookupResproxy).toHaveBeenCalledWith("5.6.7.8");
+        expect(mockReq.ipinfo_resproxy?.ip).toBe("5.6.7.8");
+    });
+
+    it("should use custom ipSelector function when provided", async () => {
+        const customSelector = jest.fn().mockReturnValue("9.10.11.12");
+
+        const middleware = ipinfoResproxy({
+            token: mockToken,
+            ipSelector: customSelector
+        });
+
+        await middleware(mockReq, mockRes, next);
+
+        expect(customSelector).toHaveBeenCalledWith(mockReq);
+        expect(mockLookupResproxy).toHaveBeenCalledWith("9.10.11.12");
+    });
+
+    it("should throw IPinfo API errors", async () => {
+        const errorMessage = "API rate limit exceeded";
+        mockLookupResproxy.mockRejectedValueOnce(new Error(errorMessage));
+        const middleware = ipinfoResproxy({ token: mockToken });
+
+        await expect(middleware(mockReq, mockRes, next)).rejects.toThrow(
+            errorMessage
+        );
+
+        expect(mockReq.ipinfo_resproxy).toBeUndefined();
+        expect(next).not.toHaveBeenCalled();
+    });
+
+    it("should pass through empty response when IP not in resproxy database", async () => {
+        // Empty object simulates IP not in resproxy database
+        mockLookupResproxy.mockResolvedValue({});
+
+        const middleware = ipinfoResproxy({ token: mockToken });
+
+        await middleware(mockReq, mockRes, next);
+
+        expect(mockLookupResproxy).toHaveBeenCalledWith("175.107.211.204");
+        expect(mockReq.ipinfo_resproxy).toEqual({});
+        expect(next).toHaveBeenCalled();
+    });
+});

package.json

@@ -36,7 +36,7 @@
         }
     },
     "dependencies": {
-        "node-ipinfo": "^4.2.0"
+        "node-ipinfo": "^4.3.0"
     },
     "devDependencies": {
         "@types/express": "^4.17.23",

src/index.ts

@@ -11,7 +11,8 @@ import {
     IPinfoLite,
     IPinfoCore,
     IPinfoPlus,
-    IPBogon
+    IPBogon,
+    Resproxy
 } from "node-ipinfo/dist/src/common";
 
 type MiddlewareOptions = {
@@ -101,11 +102,32 @@ const ipinfoPlusMiddleware = ({
     };
 };
 
+const ipinfoResproxyMiddleware = ({
+    token = "",
+    cache,
+    timeout,
+    ipSelector
+}: MiddlewareOptions = {}) => {
+    const ipinfo = new IPinfoWrapper(token, cache, timeout);
+    if (ipSelector == null || typeof ipSelector !== "function") {
+        ipSelector = defaultIPSelector;
+    }
+    return async (req: any, _: any, next: any) => {
+        const ip = ipSelector?.(req) ?? defaultIPSelector(req);
+        if (ip) {
+            const resproxy: Resproxy = await ipinfo.lookupResproxy(ip);
+            req.ipinfo_resproxy = resproxy;
+        }
+        next();
+    };
+};
+
 export default ipinfoMiddleware;
 export {
     defaultIPSelector,
     originatingIPSelector,
     ipinfoLiteMiddleware as ipinfoLite,
     ipinfoCoreMiddleware as ipinfoCore,
-    ipinfoPlusMiddleware as ipinfoPlus
+    ipinfoPlusMiddleware as ipinfoPlus,
+    ipinfoResproxyMiddleware as ipinfoResproxy
 };