feat: added support for filters in WebServer library

libraries/WebServer/src/Parsing.cpp

@@ -124,7 +124,7 @@ bool WebServer::_parseRequest(NetworkClient &client) {
   //attach handler
   RequestHandler *handler;
   for (handler = _firstHandler; handler; handler = handler->next()) {
-    if (handler->canHandle(_currentMethod, _currentUri)) {
+    if (handler->canHandle(*this, _currentMethod, _currentUri)) {
       break;
     }
   }
@@ -176,7 +176,7 @@ bool WebServer::_parseRequest(NetworkClient &client) {
       }
     }
 
-    if (!isForm && _currentHandler && _currentHandler->canRaw(_currentUri)) {
+    if (!isForm && _currentHandler && _currentHandler->canRaw(*this, _currentUri)) {
       log_v("Parse raw");
       _currentRaw.reset(new HTTPRaw());
       _currentRaw->status = RAW_START;
@@ -334,7 +334,7 @@ void WebServer::_parseArguments(String data) {
 
 void WebServer::_uploadWriteByte(uint8_t b) {
   if (_currentUpload->currentSize == HTTP_UPLOAD_BUFLEN) {
-    if (_currentHandler && _currentHandler->canUpload(_currentUri)) {
+    if (_currentHandler && _currentHandler->canUpload(*this, _currentUri)) {
       _currentHandler->upload(*this, _currentUri, *_currentUpload);
     }
     _currentUpload->totalSize += _currentUpload->currentSize;
@@ -449,7 +449,7 @@ bool WebServer::_parseForm(NetworkClient &client, String boundary, uint32_t len)
             _currentUpload->totalSize = 0;
             _currentUpload->currentSize = 0;
             log_v("Start File: %s Type: %s", _currentUpload->filename.c_str(), _currentUpload->type.c_str());
-            if (_currentHandler && _currentHandler->canUpload(_currentUri)) {
+            if (_currentHandler && _currentHandler->canUpload(*this, _currentUri)) {
               _currentHandler->upload(*this, _currentUri, *_currentUpload);
             }
             _currentUpload->status = UPLOAD_FILE_WRITE;
@@ -488,12 +488,12 @@ bool WebServer::_parseForm(NetworkClient &client, String boundary, uint32_t len)
               }
             }
             // Found the boundary string, finish processing this file upload
-            if (_currentHandler && _currentHandler->canUpload(_currentUri)) {
+            if (_currentHandler && _currentHandler->canUpload(*this, _currentUri)) {
               _currentHandler->upload(*this, _currentUri, *_currentUpload);
             }
             _currentUpload->totalSize += _currentUpload->currentSize;
             _currentUpload->status = UPLOAD_FILE_END;
-            if (_currentHandler && _currentHandler->canUpload(_currentUri)) {
+            if (_currentHandler && _currentHandler->canUpload(*this, _currentUri)) {
               _currentHandler->upload(*this, _currentUri, *_currentUpload);
             }
             log_v("End File: %s Type: %s Size: %d", _currentUpload->filename.c_str(), _currentUpload->type.c_str(), (int)_currentUpload->totalSize);
@@ -567,7 +567,7 @@ String WebServer::urlDecode(const String &text) {
 
 bool WebServer::_parseFormUploadAborted() {
   _currentUpload->status = UPLOAD_FILE_ABORTED;
-  if (_currentHandler && _currentHandler->canUpload(_currentUri)) {
+  if (_currentHandler && _currentHandler->canUpload(*this, _currentUri)) {
     _currentHandler->upload(*this, _currentUri, *_currentUpload);
   }
   return false;

libraries/WebServer/src/WebServer.cpp

@@ -21,6 +21,11 @@
 */
 
 #include <Arduino.h>
+
+#if SOC_WIFI_SUPPORTED
+  #include "WiFi.h"
+#endif
+
 #include <esp32-hal-log.h>
 #include <libb64/cdecode.h>
 #include <libb64/cencode.h>
@@ -306,16 +311,18 @@ void WebServer::requestAuthentication(HTTPAuthMethod mode, const char *realm, co
   send(401, String(FPSTR(mimeTable[html].mimeType)), authFailMsg);
 }
 
-void WebServer::on(const Uri &uri, WebServer::THandlerFunction handler) {
-  on(uri, HTTP_ANY, handler);
+RequestHandler& WebServer::on(const Uri &uri, WebServer::THandlerFunction handler) {
+  return on(uri, HTTP_ANY, handler);
 }
 
-void WebServer::on(const Uri &uri, HTTPMethod method, WebServer::THandlerFunction fn) {
-  on(uri, method, fn, _fileUploadHandler);
+RequestHandler& WebServer::on(const Uri &uri, HTTPMethod method, WebServer::THandlerFunction fn) {
+  return on(uri, method, fn, _fileUploadHandler);
 }
 
-void WebServer::on(const Uri &uri, HTTPMethod method, WebServer::THandlerFunction fn, WebServer::THandlerFunction ufn) {
-  _addRequestHandler(new FunctionRequestHandler(fn, ufn, uri, method));
+RequestHandler& WebServer::on(const Uri &uri, HTTPMethod method, WebServer::THandlerFunction fn, WebServer::THandlerFunction ufn) {
+  FunctionRequestHandler *handler = new FunctionRequestHandler(fn, ufn, uri, method);
+  _addRequestHandler(handler);
+  return *handler;
 }
 
 void WebServer::addHandler(RequestHandler *handler) {
@@ -796,3 +803,13 @@ String WebServer::_responseCodeToString(int code) {
     default:  return F("");
   }
 }
+
+#if SOC_WIFI_SUPPORTED
+  bool ON_STA_FILTER(WebServer &server) {
+    return WiFi.STA.localIP() == server.client().localIP();
+  }
+
+  bool ON_AP_FILTER(WebServer &server) {
+    return WiFi.AP.localIP() == server.client().localIP();
+  }
+#endif

libraries/WebServer/src/WebServer.h

@@ -144,9 +144,10 @@ class WebServer {
   void requestAuthentication(HTTPAuthMethod mode = BASIC_AUTH, const char *realm = NULL, const String &authFailMsg = String(""));
 
   typedef std::function<void(void)> THandlerFunction;
-  void on(const Uri &uri, THandlerFunction fn);
-  void on(const Uri &uri, HTTPMethod method, THandlerFunction fn);
-  void on(const Uri &uri, HTTPMethod method, THandlerFunction fn, THandlerFunction ufn);  //ufn handles file uploads
+  typedef std::function<bool(WebServer &server)> FilterFunction;
+  RequestHandler& on(const Uri &uri, THandlerFunction fn);
+  RequestHandler& on(const Uri &uri, HTTPMethod method, THandlerFunction fn);
+  RequestHandler& on(const Uri &uri, HTTPMethod method, THandlerFunction fn, THandlerFunction ufn);  //ufn handles file uploads
   void addHandler(RequestHandler *handler);
   void serveStatic(const char *uri, fs::FS &fs, const char *path, const char *cache_header = NULL);
   void onNotFound(THandlerFunction fn);     //called when handler is not assigned
@@ -292,4 +293,12 @@ class WebServer {
   String _srealm;  // Store the Auth realm between Calls
 };
 
+/*
+  Request Filters
+*/
+
+bool ON_STA_FILTER(WebServer &server);
+
+bool ON_AP_FILTER(WebServer &server);
+
 #endif  //ESP8266WEBSERVER_H

libraries/WebServer/src/detail/RequestHandler.h

@@ -7,6 +7,11 @@
 class RequestHandler {
 public:
   virtual ~RequestHandler() {}
+
+  /*
+    note: old handler API for backward compatibility
+  */
+
   virtual bool canHandle(HTTPMethod method, String uri) {
     (void)method;
     (void)uri;
@@ -20,6 +25,27 @@ class RequestHandler {
     (void)uri;
     return false;
   }
+
+  /*
+    note: new handler API with support for filters etc.
+  */
+
+  virtual bool canHandle(WebServer &server, HTTPMethod method, String uri) {
+    (void)server;
+    (void)method;
+    (void)uri;
+    return false;
+  }
+  virtual bool canUpload(WebServer &server, String uri) {
+    (void)server;
+    (void)uri;
+    return false;
+  }
+  virtual bool canRaw(WebServer &server, String uri) {
+    (void)server;
+    (void)uri;
+    return false;
+  }
   virtual bool handle(WebServer &server, HTTPMethod requestMethod, String requestUri) {
     (void)server;
     (void)requestMethod;
@@ -37,6 +63,11 @@ class RequestHandler {
     (void)raw;
   }
 
+  virtual RequestHandler& setFilter(std::function<bool(WebServer&)> filter) {
+    (void)filter;
+    return *this;
+  }
+
   RequestHandler *next() {
     return _next;
   }

libraries/WebServer/src/detail/RequestHandlersImpl.h

@@ -36,6 +36,7 @@ class FunctionRequestHandler : public RequestHandler {
 
     return true;
   }
+
   bool canRaw(String requestUri) override {
     if (!_ufn || _method == HTTP_GET) {
       return false;
@@ -44,9 +45,32 @@ class FunctionRequestHandler : public RequestHandler {
     return true;
   }
 
+  bool canHandle(WebServer &server, HTTPMethod requestMethod, String requestUri) override {
+    if (_method != HTTP_ANY && _method != requestMethod) {
+      return false;
+    }
+
+    return _uri->canHandle(requestUri, pathArgs) && (_filter != NULL ? _filter(server) : true);
+  }
+
+  bool canUpload(WebServer &server, String requestUri) override {
+    if (!_ufn || !canHandle(server, HTTP_POST, requestUri)) {
+      return false;
+    }
+
+    return true;
+  }
+
+  bool canRaw(WebServer &server, String requestUri) override {
+    if (!_ufn || _method == HTTP_GET || (_filter != NULL ? _filter(server) == false : false)) {
+      return false;
+    }
+
+    return true;
+  }
+
   bool handle(WebServer &server, HTTPMethod requestMethod, String requestUri) override {
-    (void)server;
-    if (!canHandle(requestMethod, requestUri)) {
+    if (!canHandle(server, requestMethod, requestUri)) {
       return false;
     }
 
@@ -55,24 +79,30 @@ class FunctionRequestHandler : public RequestHandler {
   }
 
   void upload(WebServer &server, String requestUri, HTTPUpload &upload) override {
-    (void)server;
     (void)upload;
-    if (canUpload(requestUri)) {
+    if (canUpload(server, requestUri)) {
       _ufn();
     }
   }
 
   void raw(WebServer &server, String requestUri, HTTPRaw &raw) override {
-    (void)server;
     (void)raw;
-    if (canRaw(requestUri)) {
+    if (canRaw(server, requestUri)) {
       _ufn();
     }
   }
 
+  FunctionRequestHandler& setFilter(WebServer::FilterFunction filter) {
+    _filter = filter;
+    return *this;
+  }
+
 protected:
   WebServer::THandlerFunction _fn;
   WebServer::THandlerFunction _ufn;
+  // _filter should return 'true' when the request should be handled
+  // and 'false' when the request should be ignored
+  WebServer::FilterFunction _filter;
   Uri *_uri;
   HTTPMethod _method;
 };
@@ -100,8 +130,24 @@ class StaticRequestHandler : public RequestHandler {
     return true;
   }
 
+  bool canHandle(WebServer &server, HTTPMethod requestMethod, String requestUri) override {
+    if (requestMethod != HTTP_GET) {
+      return false;
+    }
+
+    if ((_isFile && requestUri != _uri) || !requestUri.startsWith(_uri)) {
+      return false;
+    }
+
+    if (_filter != NULL ? _filter(server) == false : false) {
+      return false;
+    }
+
+    return true;
+  }
+
   bool handle(WebServer &server, HTTPMethod requestMethod, String requestUri) override {
-    if (!canHandle(requestMethod, requestUri)) {
+    if (!canHandle(server, requestMethod, requestUri)) {
       return false;
     }
 
@@ -197,7 +243,15 @@ class StaticRequestHandler : public RequestHandler {
     return (result);
   }  // calcETag
 
+  StaticRequestHandler& setFilter(WebServer::FilterFunction filter) {
+    _filter = filter;
+    return *this;
+  }
+
 protected:
+  // _filter should return 'true' when the request should be handled
+  // and 'false' when the request should be ignored
+  WebServer::FilterFunction _filter;
   FS _fs;
   String _uri;
   String _path;