bugfix2/ESP8266HTTPClient

libraries/ESP8266HTTPClient/examples/ReuseConnectionV2/ReuseConnectionV2.ino

@@ -0,0 +1,82 @@
+/**
+   reuseConnectionV2.ino
+
+    Created on: 22.11.2015
+
+   This example reuses the http connection and also restores the connection if the connection is lost
+*/
+
+
+#include <ESP8266WiFi.h>
+#include <ESP8266WiFiMulti.h>
+#include <ESP8266HTTPClient.h>
+
+#ifndef STASSID
+#define STASSID "your-ssid"
+#define STAPSK  "your-password"
+#endif
+
+ESP8266WiFiMulti WiFiMulti;
+
+HTTPClient http;
+WiFiClient client;
+
+void setup() {
+
+  Serial.begin(115200);
+  // Serial.setDebugOutput(true);
+
+  Serial.println();
+  Serial.println();
+  Serial.println("Connecting to WiFi...");
+
+  WiFi.mode(WIFI_STA);
+  WiFiMulti.addAP(STASSID, STAPSK);
+
+  // wait for WiFi connection
+  while ((WiFiMulti.run() != WL_CONNECTED)) {
+    Serial.write('.');
+    delay(500);
+  }
+  Serial.println(" connected to WiFi");
+
+  // allow reuse (if server supports it)
+  http.setReuse(true);
+
+
+  http.begin(client, "http://jigsaw.w3.org/HTTP/connection.html");
+  //http.begin(client, "jigsaw.w3.org", 80, "/HTTP/connection.html");
+}
+
+int pass = 0;
+
+void loop() {
+  // First 10 loop()s, retrieve the URL
+  if (pass < 10) {
+    pass++;
+    Serial.printf("Reuse connection example, GET url for the %d time\n", pass);
+    int httpCode = http.GET();
+    if (httpCode > 0) {
+      Serial.printf("[HTTP] GET... code: %d\n", httpCode);
+
+      // file found at server
+      if (httpCode == HTTP_CODE_OK) {
+        http.writeToStream(&Serial);
+      }
+    } else {
+      Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
+      // Something went wrong with the connection, try to reconnect
+      http.end();
+      http.begin(client, "http://jigsaw.w3.org/HTTP/connection.html");
+      //http.begin(client, "jigsaw.w3.org", 80, "/HTTP/connection.html");
+    }
+
+    if (pass == 10) {
+      http.end();
+      Serial.println("Done testing");
+    } else {
+      Serial.println("\n\n\nWait 5 second...\n");
+      delay(5000);
+    }
+  }
+}

libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp

@@ -457,6 +457,10 @@ void HTTPClient::disconnect(bool preserveClient)
 #endif
         }
     } else {
+        if (!preserveClient && _client) { // Also destroy _client if not connected()
+            _client = nullptr;
+        }
+
         DEBUG_HTTPCLIENT("[HTTP-Client][end] tcp is closed\n");
     }
 }
@@ -970,7 +974,9 @@ int HTTPClient::writeToStream(Stream * stream)
         return returnError(HTTPC_ERROR_NO_STREAM);
     }
 
-    if(!connected()) {
+    // Only return error if not connected and no data available, because otherwise ::getString() will return an error instead of an empty
+    // string when the server returned a http code 204 (no content)
+    if(!connected() && _transferEncoding != HTTPC_TE_IDENTITY && _size > 0) {
         return returnError(HTTPC_ERROR_NOT_CONNECTED);
     }
 
@@ -979,11 +985,13 @@ int HTTPClient::writeToStream(Stream * stream)
     int ret = 0;
 
     if(_transferEncoding == HTTPC_TE_IDENTITY) {
-        ret = writeToStreamDataBlock(stream, len);
+        if(len > 0) {
+            ret = writeToStreamDataBlock(stream, len);
 
-        // have we an error?
-        if(ret < 0) {
-            return returnError(ret);
+            // have we an error?
+            if(ret < 0) {
+                return returnError(ret);
+            }
         }
     } else if(_transferEncoding == HTTPC_TE_CHUNKED) {
         int size = 0;
@@ -1198,12 +1206,8 @@ bool HTTPClient::hasHeader(const char* name)
  */
 bool HTTPClient::connect(void)
 {
-    if(connected()) {
-        if(_reuse) {
-            DEBUG_HTTPCLIENT("[HTTP-Client] connect: already connected, reusing connection\n");
-        } else {
-            DEBUG_HTTPCLIENT("[HTTP-Client] connect: already connected, try reuse!\n");
-        }
+    if(_reuse && _canReuse && connected()) {
+        DEBUG_HTTPCLIENT("[HTTP-Client] connect: already connected, reusing connection\n");
         while(_client->available() > 0) {
             _client->read();
         }
@@ -1334,22 +1338,21 @@ int HTTPClient::handleHeaderResponse()
     while(connected()) {
         size_t len = _client->available();
         if(len > 0) {
+            int headerSeparator = -1;
             String headerLine = _client->readStringUntil('\n');
 
             lastDataTime = millis();
 
             DEBUG_HTTPCLIENT("[HTTP-Client][handleHeaderResponse] RX: '%s'\n", headerLine.c_str());
 
             if (headerLine.startsWith(F("HTTP/1."))) {
-                if (_canReuse) {
-                    _canReuse = (headerLine[sizeof "HTTP/1." - 1] != '0');
-                }
-                _returnCode = headerLine.substring(9, headerLine.indexOf(' ', 9)).toInt();
-                continue;
-            }
 
-            int headerSeparator = headerLine.indexOf(':');
-            if (headerSeparator > 0) {
+                constexpr auto httpVersionIdx = sizeof "HTTP/1." - 1;
+                _canReuse = _canReuse && (headerLine[httpVersionIdx] != '0');
+                _returnCode = headerLine.substring(httpVersionIdx + 2, headerLine.indexOf(' ', httpVersionIdx + 2)).toInt();
+                _canReuse = _canReuse && (_returnCode > 0) && (_returnCode < 500);
+
+            } else if ((headerSeparator = headerLine.indexOf(':')) > 0) {
                 String headerName = headerLine.substring(0, headerSeparator);
                 String headerValue = headerLine.substring(headerSeparator + 1);
                 headerValue.trim();