webserver hook: allow to handle external http protocol

libraries/ESP8266WebServer/src/ESP8266WebServer-impl.h

@@ -35,6 +35,12 @@
 #define DEBUG_OUTPUT Serial
 #endif
 
+#ifdef DEBUG_ESP_HTTP_SERVER
+#define DBGWS(x...) do { DEBUG_OUTPUT.printf(x); } while (0)
+#else
+#define DBGWS(x...) do { (void)0; } while (0)
+#endif
+
 static const char AUTHORIZATION_HEADER[] PROGMEM = "Authorization";
 static const char qop_auth[] PROGMEM = "qop=auth";
 static const char qop_auth_quoted[] PROGMEM = "qop=\"auth\"";
@@ -326,6 +332,13 @@ void ESP8266WebServerTemplate<ServerType>::handleClient() {
   bool keepCurrentClient = false;
   bool callYield = false;
 
+  DBGWS("http-server loop: conn=%d avail=%d status=%s\n",
+    _currentClient.connected(), _currentClient.available(),
+    _currentStatus==HC_NONE?"none":
+    _currentStatus==HC_WAIT_READ?"wait-read":
+    _currentStatus==HC_WAIT_CLOSE?"wait-close":
+    "??");
+
   if (_currentClient.connected() || _currentClient.available()) {
     switch (_currentStatus) {
     case HC_NONE:
@@ -334,34 +347,57 @@ void ESP8266WebServerTemplate<ServerType>::handleClient() {
     case HC_WAIT_READ:
       // Wait for data from client to become available
       if (_currentClient.available()) {
-        if (_parseRequest(_currentClient)) {
+        switch (_parseRequest(_currentClient))
+        {
+        case CLIENT_REQUEST_CAN_CONTINUE:
           _currentClient.setTimeout(HTTP_MAX_SEND_WAIT);
           _contentLength = CONTENT_LENGTH_NOT_SET;
           _handleRequest();
-
-          if (_currentClient.connected()) {
+          /* fallthrough */
+        case CLIENT_REQUEST_IS_HANDLED:
+          if (_currentClient.connected() || _currentClient.available()) {
             _currentStatus = HC_WAIT_CLOSE;
             _statusChange = millis();
             keepCurrentClient = true;
           }
-        }
-      } else { // !_currentClient.available()
+          else
+            DBGWS("webserver: peer has closed after served\n");
+          break;
+        case CLIENT_MUST_STOP:
+          DBGWS("Close client\n");
+          _currentClient.stop();
+          break;
+        case CLIENT_IS_GIVEN:
+          // client must not be stopped but must not be handled here anymore
+          // (example: tcp connection given to websocket)
+          DBGWS("Give client\n");
+          break;
+        } // switch _parseRequest()
+      } else {
+        // !_currentClient.available(): waiting for more data
         if (millis() - _statusChange <= HTTP_MAX_DATA_WAIT) {
           keepCurrentClient = true;
         }
+        else
+          DBGWS("webserver: closing after read timeout\n");
         callYield = true;
       }
       break;
     case HC_WAIT_CLOSE:
       // Wait for client to close the connection
-      if (millis() - _statusChange <= HTTP_MAX_CLOSE_WAIT) {
+      if (!_server.available() && (millis() - _statusChange <= HTTP_MAX_CLOSE_WAIT)) {
         keepCurrentClient = true;
         callYield = true;
+        if (_currentClient.available())
+            // continue serving current client
+            _currentStatus = HC_WAIT_READ;
       }
-    }
+      break;
+    } // switch _currentStatus
   }
 
   if (!keepCurrentClient) {
+    DBGWS("Drop client\n");
     _currentClient = ClientType();
     _currentStatus = HC_NONE;
     _currentUpload.reset();

libraries/ESP8266WebServer/src/ESP8266WebServer.h

@@ -26,6 +26,7 @@
 
 #include <functional>
 #include <memory>
+#include <functional>
 #include <ESP8266WiFi.h>
 #include <FS.h>
 #include "detail/mimetable.h"
@@ -80,6 +81,9 @@ class ESP8266WebServerTemplate
   using ClientType = typename ServerType::ClientType;
   using RequestHandlerType = RequestHandler<ServerType>;
   using WebServerType = ESP8266WebServerTemplate<ServerType>;
+  using ContentType_f = std::function<String(const String&)>;
+  enum ClientFuture_e { CLIENT_REQUEST_CAN_CONTINUE, CLIENT_REQUEST_IS_HANDLED, CLIENT_MUST_STOP, CLIENT_IS_GIVEN };
+  using Hook_f = std::function<ClientFuture_e(const String& method, const String& url, WiFiClient* client, ContentType_f contentType)>;
 
   void begin();
   void begin(uint16_t port);
@@ -192,11 +196,28 @@ class ESP8266WebServerTemplate
 
   static String responseCodeToString(const int code);
 
+  void addHook (Hook_f hook)
+  {
+    if (_hook)
+    {
+      auto previous = _hook;
+      _hook = [previous, hook](const String& method, const String& url, WiFiClient* client, ContentType_f contentType)
+        {
+          auto whatNow = previous(method, url, client, contentType);
+          if (whatNow == CLIENT_REQUEST_CAN_CONTINUE)
+            return hook(method, url, client, contentType);
+          return whatNow;
+        };
+    }
+    else
+      _hook = hook;
+  }
+
 protected:
   void _addRequestHandler(RequestHandlerType* handler);
   void _handleRequest();
   void _finalizeResponse();
-  bool _parseRequest(ClientType& client);
+  ClientFuture_e _parseRequest(ClientType& client);
   void _parseArguments(const String& data);
   int _parseArgumentsPrivate(const String& data, std::function<void(String&,String&,const String&,int,int,int,int)> handler);
   bool _parseForm(ClientType& client, const String& boundary, uint32_t len);
@@ -252,8 +273,7 @@ class ESP8266WebServerTemplate
   String           _sopaque;
   String           _srealm;  // Store the Auth realm between Calls
 
-
-
+  Hook_f           _hook;
 };
 
 

libraries/ESP8266WebServer/src/Parsing-impl.h

@@ -61,7 +61,7 @@ static bool readBytesWithTimeout(typename ServerType::ClientType& client, size_t
 }
 
 template <typename ServerType>
-bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
+typename ESP8266WebServerTemplate<ServerType>::ClientFuture_e ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
   // Read the first line of HTTP request
   String req = client.readStringUntil('\r');
 #ifdef DEBUG_ESP_HTTP_SERVER
@@ -71,7 +71,7 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
   client.readStringUntil('\n');
   //reset header value
   for (int i = 0; i < _headerKeysCount; ++i) {
-    _currentHeaders[i].value =String();
+    _currentHeaders[i].value.clear();
    }
 
   // First line of HTTP request looks like "GET /path HTTP/1.1"
@@ -82,7 +82,7 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
 #ifdef DEBUG_ESP_HTTP_SERVER
     DEBUG_OUTPUT.println("Invalid request");
 #endif
-    return false;
+    return CLIENT_MUST_STOP;
   }
 
   String methodStr = req.substring(0, addr_start);
@@ -98,6 +98,13 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
   _currentUri = url;
   _chunked = false;
 
+  if (_hook)
+  {
+    auto whatNow = _hook(methodStr, url, &client, mime::getContentType);
+    if (whatNow != CLIENT_REQUEST_CAN_CONTINUE)
+        return whatNow;
+  }
+
   HTTPMethod method = HTTP_GET;
   if (methodStr == F("HEAD")) {
     method = HTTP_HEAD;
@@ -188,7 +195,7 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
            )
        )
     {
-        return false;
+        return CLIENT_MUST_STOP;
     }
 
     if (isEncoded) {
@@ -213,7 +220,7 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
     } else { // isForm is true
       // here: content is not yet read (plainBuf is still empty)
       if (!_parseForm(client, boundaryStr, contentLength)) {
-        return false;
+        return CLIENT_MUST_STOP;
       }
     }
   } else {
@@ -260,7 +267,7 @@ bool ESP8266WebServerTemplate<ServerType>::_parseRequest(ClientType& client) {
       _currentArgs[i].value.c_str());
 #endif
 
-  return true;
+  return CLIENT_REQUEST_CAN_CONTINUE;
 }
 
 template <typename ServerType>