feat!: add support for relative routes in nested SVRouter routers

README.md

@@ -64,7 +64,9 @@ The _callback_ parameter has these arguments of the SVR.JS mod callback:
  - _config_ - the SVR.JS configuration object
  - _next_ - the callback which passes the execution to other routes, SVR.JS mods and SVR.JS internal handlers.
 
-The _req_ object has an additional _params_ parameter, which contains request parameters, for example if the request URL is `/api/task/1`, and the route path is `/api/task/:id`, then the _req.params_ object is a `null` prototype object with the `id` property set to `"1"`.
+The _req_ object has an additional _params_ property, which contains request parameters, for example if the request URL is `/api/task/1`, and the route path is `/api/task/:id`, then the _req.params_ object is a `null` prototype object with the `id` property set to `"1"`.
+
+The _req_ object has another additional _svrouterBase_ property, which contains the route base used internally by a SVRouter router. It's not recommended to override this property, as doing it may result in a SVRouter router behaving erratically.
 
 You can read more about the SVR.JS mod callbacks in the [SVR.JS mod API documentation](https://svrjs.org/docs/api/svrjs-api).
 
@@ -76,7 +78,7 @@ Parameters:
 
 Returns: the SVRouter router (so that you can chain the methods for routes or pass-throughs)
 
-The function adds a pass-through (can be middleware) to the SVRouter router. The pass-through can be to an another SVRouter router (the absolute request URLs need to be provided for the _router.route_ function in the SVRouter router). Note that the request URL is not rewritten though, unlike in the `router` library, so if you write middleware for SVRouter, you may need to include the request URL prefix in the parameters of the function that returns the SVR.JS mod callback.
+The function adds a pass-through (can be middleware) to the SVRouter router. The pass-through can be to an another SVRouter router (the request URLs relative to a parent route need to be provided for the _router.route_ function in the SVRouter router).
 
 The _callback_ parameter has these arguments of the SVR.JS mod callback:
  - _req_ - the SVR.JS request object
@@ -85,6 +87,8 @@ The _callback_ parameter has these arguments of the SVR.JS mod callback:
  - _config_ - the SVR.JS configuration object
  - _next_ - the callback which passes the execution to other routes, SVR.JS mods and SVR.JS internal handlers.
 
+The _req_ object has an additional _svrouterBase_ property, which contains the route base used internally by a SVRouter router. It's not recommended to override this property, as doing it may result in a SVRouter router behaving erratically.
+
 You can read more about the SVR.JS mod callbacks in the [SVR.JS mod API documentation](https://svrjs.org/docs/api/svrjs-api).
 
 ### _router.passExpressRouterMiddleware([path, ]middleware)_

src/index.js

@@ -3,19 +3,25 @@ const http = require("http");
 
 function svrouter() {
   const routes = [];
-
   const router = (req, res, logFacilities, config, next) => {
     let index = 0;
     let previousReqParams = req.params;
+    let previousReqSvrouterBase = req.svrouterBase;
     let paramsPresent = false;
+    let passPathPresent = false;
 
     const nextRoute = () => {
       if (paramsPresent) req.params = previousReqParams;
+      if (passPathPresent) req.svrouterBase = previousReqSvrouterBase;
       let currentRoute = routes[index++];
       let currentMatch =
         currentRoute && currentRoute.pathFunction
-          ? currentRoute.pathFunction(req.parsedURL.pathname)
+          ? currentRoute.pathFunction(
-          : false;
+              req.parsedURL.pathname.substring(
+                (req.svrouterBase ? req.svrouterBase : "").length
+              )
+            )
+          : false; // Let's assume the request URL begins with the contents of the req.svrouterBase property.
       while (
         currentRoute &&
         ((currentRoute.method && req.method != currentRoute.method) ||
@@ -24,17 +30,26 @@ function svrouter() {
         currentRoute = routes[index++];
         currentMatch =
           currentRoute && currentRoute.pathFunction
-            ? currentRoute.pathFunction(req.parsedURL.pathname)
+            ? currentRoute.pathFunction(
+                req.parsedURL.pathname.substring(
+                  (req.svrouterBase ? req.svrouterBase : "").length
+                )
+              )
             : false;
       }
       if (currentRoute && currentRoute.callback) {
         try {
           paramsPresent = Boolean(currentMatch.params);
+          passPathPresent = Boolean(currentRoute.passPath);
           if (paramsPresent)
             req.params =
               currentMatch && currentMatch.params
                 ? currentMatch.params
                 : Object.create(null);
+          if (passPathPresent)
+            req.svrouterBase =
+              (req.svrouterBase ? req.svrouterBase : "") +
+              currentRoute.passPath;
           currentRoute.callback(req, res, logFacilities, config, nextRoute);
         } catch (err) {
           res.error(500, err);
@@ -59,7 +74,8 @@ function svrouter() {
     routes.push({
       method: method === "*" ? null : method.toUpperCase(),
       pathFunction: match(path),
-      callback: callback
+      callback: callback,
+      passPath: null
     });
 
     return router;
@@ -86,7 +102,8 @@ function svrouter() {
                 }
               : false
         : () => true,
-      callback: realCallback
+      callback: realCallback,
+      passPath: realPath
     });
 
     return router;
@@ -105,16 +122,20 @@ function svrouter() {
       const previousReqBaseUrl = req.baseUrl;
       const previousReqUrl = req.url;
       const previousReqOriginalUrl = req.originalUrl;
+      const previousReqSvrouterBase = req.svrouterBase;
 
-      req.baseUrl = realPath;
+      const svrouterBase = req.svrouterBase ? req.svrouterBase : "";
+      req.baseUrl = svrouterBase;
       req.originalUrl = req.url;
-      req.url = req.url.substr(realPath.length); // Let's assume the request URL begins with the contents of realPath variable.
+      req.url = req.url.substr(svrouterBase.length); // Let's assume the request URL begins with the contents of svrouterBase variable.
       if (!req.url) req.url = "/";
+      req.svrouterBase = undefined;
 
       const nextCallback = () => {
         req.baseUrl = previousReqBaseUrl;
         req.url = previousReqUrl;
         req.originalUrl = previousReqOriginalUrl;
+        req.svrouterBase = previousReqSvrouterBase;
         next();
       };
 

tests/index.test.js

@@ -228,7 +228,7 @@ describe("SVRouter", () => {
     expect(res.end).toHaveBeenCalledWith("Middleware matched");
   });
 
-  test("should restore req.url and req.baseUrl after middleware runs", () => {
+  test("should restore req.url and req.baseUrl after middleware added with passExpressRouterMiddleware runs", () => {
     const req = {
       method: "GET",
       parsedURL: { pathname: "/api/resource" },
@@ -312,6 +312,113 @@ describe("SVRouter", () => {
     expect(res.secondMiddlewareRan).toBe(true);
   });
 
+  test("should handle nested routers correctly", () => {
+    const childRouter = svrouter();
+
+    const req = {
+      method: "GET",
+      parsedURL: { pathname: "/parent/child/resource" },
+      params: null
+    };
+    const res = {
+      end: jest.fn()
+    };
+
+    childRouter.get("/child/resource", (req, res) => {
+      res.end("Child router route matched");
+    });
+
+    router.pass("/parent", childRouter);
+
+    router(req, res, null, null, () => {
+      res.end("No route matched");
+    });
+
+    expect(res.end).toHaveBeenCalledWith("Child router route matched");
+  });
+
+  test("should fallback to parent router if no route matches in child router", () => {
+    const childRouter = svrouter();
+
+    const req = {
+      method: "GET",
+      parsedURL: { pathname: "/parent/child/resource" },
+      params: null
+    };
+    const res = {
+      end: jest.fn()
+    };
+
+    router.pass("/parent", childRouter);
+    router.get("/parent/child/resource", (req, res) => {
+      res.end("Parent router fallback route matched");
+    });
+
+    router(req, res, null, null, () => {
+      res.end("No route matched");
+    });
+
+    expect(res.end).toHaveBeenCalledWith(
+      "Parent router fallback route matched"
+    );
+  });
+
+  test("should handle parameterized routes in nested routers", () => {
+    const childRouter = svrouter();
+
+    const req = {
+      method: "GET",
+      parsedURL: { pathname: "/parent/user/42/details" },
+      params: null
+    };
+    const res = {
+      end: jest.fn()
+    };
+
+    childRouter.get("/user/:id/details", (req, res) => {
+      res.end(`User ID is ${req.params.id}`);
+    });
+
+    router.pass("/parent", childRouter);
+
+    router(req, res, null, null, () => {
+      res.end("No route matched");
+    });
+
+    expect(res.end).toHaveBeenCalledWith("User ID is 42");
+  });
+
+  test("should handle multiple nested routers", () => {
+    const childRouter1 = svrouter();
+    const childRouter2 = svrouter();
+
+    const req = {
+      method: "GET",
+      parsedURL: { pathname: "/parent/child2/resource" },
+      params: null
+    };
+    const res = {
+      end: jest.fn()
+    };
+
+    childRouter1.get("/resource", (req, res) => {
+      res.end("Child router 1 route matched");
+    });
+
+    childRouter2.get("/resource", (req, res) => {
+      res.end("Child router 2 route matched");
+    });
+
+    router.pass("/parent/child1", childRouter1);
+    router.pass("/parent/child2", childRouter2);
+
+    router(req, res, null, null, () => {
+      res.end("No route matched");
+    });
+
+    expect(res.end).toHaveBeenCalledWith("Child router 2 route matched");
+  });
+
   test("should throw an error if method is not a string in route", () => {
     expect(() => {
       router.route(123, "/path", () => {});