From 02438bfdf0e74936faa98baeaca5444b13cbc428 Mon Sep 17 00:00:00 2001
From: Christopher Liebman <liebman@zod.com>
Date: Sun, 5 Aug 2018 07:00:26 -0700
Subject: [PATCH 1/9] optionally allow redirects on http OTA updates

---
 .../src/ESP8266HTTPClient.cpp                 | 23 +++++++++++++++++++
 .../ESP8266HTTPClient/src/ESP8266HTTPClient.h |  2 +-
 .../src/ESP8266httpUpdate.cpp                 | 19 ++++++++++++---
 .../ESP8266httpUpdate/src/ESP8266httpUpdate.h |  6 +++++
 4 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index 28a3503484..0abc743b89 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -369,6 +369,29 @@ void HTTPClient::setTimeout(uint16_t timeout)
     }
 }
 
+/**
+ * set the URL to a new value. Handy for following redirects.
+ * @param url
+ */
+bool HTTPClient::setURL(String url)
+{
+    // check for : (http: or https:)
+    int index = url.indexOf(':');
+    if(index < 0) {
+        DEBUG_HTTPCLIENT("[HTTP-Client][begin] failed to parse protocol\n");
+        return false;
+    }
+
+    String protocol = url.substring(0, index);
+    if(protocol != "http" && protocol != "https") {
+        DEBUG_HTTPCLIENT("[HTTP-Client][begin] unknown protocol '%s'\n", protocol.c_str());
+        return false;
+    }
+
+    _port = (protocol == "https" ? 443 : 80);
+    return beginInternal(url, protocol.c_str());
+}
+
 /**
  * use HTTP1.0
  * @param timeout
diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
index 72b42853f7..4c499aced5 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
@@ -154,7 +154,7 @@ class HTTPClient
     void setAuthorization(const char * user, const char * password);
     void setAuthorization(const char * auth);
     void setTimeout(uint16_t timeout);
-
+    bool setURL(String url); // handy for handling redirects
     void useHTTP10(bool usehttp10 = true);
 
     /// request handling
diff --git a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
index 5cc4b6a09e..a73352be46 100644
--- a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
+++ b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
@@ -30,12 +30,12 @@ extern "C" uint32_t _SPIFFS_start;
 extern "C" uint32_t _SPIFFS_end;
 
 ESP8266HTTPUpdate::ESP8266HTTPUpdate(void)
-        : _httpClientTimeout(8000)
+        : _httpClientTimeout(8000), _followRedirects(false)
 {
 }
 
 ESP8266HTTPUpdate::ESP8266HTTPUpdate(int httpClientTimeout)
-        : _httpClientTimeout(httpClientTimeout)
+        : _httpClientTimeout(httpClientTimeout), _followRedirects(false)
 {
 }
 
@@ -219,7 +219,7 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
         http.addHeader(F("x-ESP8266-version"), currentVersion);
     }
 
-    const char * headerkeys[] = { "x-MD5" };
+    const char * headerkeys[] = { "x-MD5" , "Location"};
     size_t headerkeyssize = sizeof(headerkeys) / sizeof(char*);
 
     // track these headers
@@ -227,6 +227,19 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
 
 
     int code = http.GET();
+    while(_followRedirects && (code == 302 || code == 301))
+    {
+        String location = http.header("Location");
+        DEBUG_HTTP_UPDATE("[httpUpdate] HTTP redirect(%d): %s\n", code, location.c_str());
+        http.end();
+        if (!http.setURL(location))
+        {
+            DEBUG_HTTP_UPDATE("[httpUpdate] Bad redirect location: '%s'", location.c_str());
+            _lastError = code;
+            return HTTP_UPDATE_FAILED;
+        }
+        code = http.GET();
+    }
     int len = http.getSize();
 
     if(code <= 0) {
diff --git a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.h b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.h
index 1676d51dfc..978684aad1 100644
--- a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.h
+++ b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.h
@@ -72,6 +72,11 @@ class ESP8266HTTPUpdate
         _rebootOnUpdate = reboot;
     }
 
+    void followRedirects(bool follow)
+    {
+    	_followRedirects = follow;
+    }
+
     // This function is deprecated, use rebootOnUpdate and the next one instead
     t_httpUpdate_return update(const String& url, const String& currentVersion,
                                const String& httpsFingerprint, bool reboot) __attribute__((deprecated));
@@ -111,6 +116,7 @@ class ESP8266HTTPUpdate
     bool _rebootOnUpdate = true;
 private:
     int _httpClientTimeout;
+    bool _followRedirects;
 };
 
 #if !defined(NO_GLOBAL_INSTANCES) && !defined(NO_GLOBAL_HTTPUPDATE)

From 8721924c607263ae96df4b60d817b29da338cb7a Mon Sep 17 00:00:00 2001
From: Chris Liebman <chris.l@taboola.com>
Date: Sat, 29 Sep 2018 16:39:41 -0700
Subject: [PATCH 2/9] Refactored HTTPClient::begin(url...) & setURL functions,
 now only beginInternal parses URL, sets ports Added HTTPRedirect example.

---
 .../examples/HTTPRedirect/HTTPRedirect.ino    | 91 +++++++++++++++++++
 .../src/ESP8266HTTPClient.cpp                 | 32 +++----
 2 files changed, 106 insertions(+), 17 deletions(-)
 create mode 100644 libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino

diff --git a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
new file mode 100644
index 0000000000..5109e13f64
--- /dev/null
+++ b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
@@ -0,0 +1,91 @@
+/**
+   HTTPRedirect.ino
+
+    Created on: 29-Sep-2018
+
+*/
+
+#include <Arduino.h>
+
+#include <ESP8266WiFi.h>
+#include <ESP8266WiFiMulti.h>
+#include <ESP8266HTTPClient.h>
+
+#define WIFI_SSID "SSID"
+#define WIFI_PASS "Password"
+
+
+ESP8266WiFiMulti WiFiMulti;
+
+
+void setup() {
+
+    Serial.begin(115200);
+  // Serial.setDebugOutput(true);
+    Serial.println();
+    Serial.println();
+    Serial.println();
+
+  for (uint8_t t = 10; t > 0; t--) {
+      Serial.printf("[SETUP] WAIT %d...\n", t);
+      Serial.flush();
+    delay(1000);
+  }
+
+  WiFi.mode(WIFI_STA);
+  WiFiMulti.addAP(WIFI_SSID, WIFI_PASS);
+
+}
+
+void loop() {
+  // wait for WiFi connection
+  if ((WiFiMulti.run() == WL_CONNECTED)) {
+
+    HTTPClient http;
+
+    // we need the Location header to handle redirects
+    const char * headerkeys[] = { "Location" };
+    size_t headerkeyssize = sizeof(headerkeys) / sizeof(char*);
+
+    // track these headers
+    http.collectHeaders(headerkeys, headerkeyssize);
+
+    Serial.print("[HTTP] begin...\n");
+    // configure url
+    http.begin("http://jigsaw.w3.org/HTTP/300/307.html"); //HTTP
+
+    Serial.print("[HTTP] GET...\n");
+    // start connection and send HTTP header
+    int httpCode = http.GET();
+
+    // As long as we get redirects, follow them
+    while(httpCode == 301 || httpCode == 302 || httpCode == 307) {
+        String location = http.header("Location");
+        Serial.printf("[HTTP] redirect(%d): %s\n", httpCode, location.c_str());
+        http.end();
+        if (!http.setURL(location)) {
+            Serial.printf("[HTTP] Bad redirect location: '%s'", location.c_str());
+            return;
+        }
+        httpCode = http.GET();
+    }
+
+    // httpCode will be negative on error
+    if (httpCode > 0) {
+      // HTTP header has been send and Server response header has been handled
+        Serial.printf("[HTTP] GET... httpCode: %d\n", httpCode);
+
+      // file found at server
+      if (httpCode == HTTP_CODE_OK) {
+        String payload = http.getString();
+        Serial.println(payload);
+      }
+    } else {
+        Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
+    }
+
+    http.end();
+  }
+
+  delay(10000);
+}
diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index 3e230d08c3..8e72a14b53 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -133,7 +133,6 @@ void HTTPClient::clear()
 bool HTTPClient::begin(String url, String httpsFingerprint)
 {
     _transportTraits.reset(nullptr);
-    _port = 443;
     if (httpsFingerprint.length() == 0) {
         return false;
     }
@@ -149,7 +148,6 @@ bool HTTPClient::begin(String url, String httpsFingerprint)
 bool HTTPClient::begin(String url, const uint8_t httpsFingerprint[20])
 {
     _transportTraits.reset(nullptr);
-    _port = 443;
     if (!beginInternal(url, "https")) {
         return false;
     }
@@ -170,7 +168,6 @@ bool HTTPClient::begin(String url, const uint8_t httpsFingerprint[20])
 bool HTTPClient::begin(String url)
 {
     _transportTraits.reset(nullptr);
-    _port = 80;
     if (!beginInternal(url, "http")) {
         return false;
     }
@@ -193,6 +190,17 @@ bool HTTPClient::beginInternal(String url, const char* expectedProtocol)
     _protocol = url.substring(0, index);
     url.remove(0, (index + 3)); // remove http:// or https://
 
+    if (_protocol == "http") {
+        // set default port for 'http'
+        _port = 80;
+    } else if (_protocol == "https") {
+        // set default port for 'https'
+        _port = 443;
+    } else {
+        DEBUG_HTTPCLIENT("[HTTP-Client][begin] unsupported protocol: %s\n", _protocol.c_str());
+        return false;
+    }
+
     index = url.indexOf('/');
     String host = url.substring(0, index);
     url.remove(0, index); // remove host part
@@ -217,7 +225,7 @@ bool HTTPClient::beginInternal(String url, const char* expectedProtocol)
     }
     _uri = url;
 
-    if (_protocol != expectedProtocol) {
+    if ( expectedProtocol != nullptr && _protocol != expectedProtocol) {
         DEBUG_HTTPCLIENT("[HTTP-Client][begin] unexpected protocol: %s, expected %s\n", _protocol.c_str(), expectedProtocol);
         return false;
     }
@@ -386,21 +394,11 @@ void HTTPClient::setTimeout(uint16_t timeout)
  */
 bool HTTPClient::setURL(String url)
 {
-    // check for : (http: or https:)
-    int index = url.indexOf(':');
-    if(index < 0) {
-        DEBUG_HTTPCLIENT("[HTTP-Client][begin] failed to parse protocol\n");
+    if (!url.startsWith(_protocol + ":")) {
+        DEBUG_HTTPCLIENT("[HTTP-Client][setURL] new URL not the same protocol, expected '%s', URL: '%s'\n", _protocol.c_str(), url.c_str());
         return false;
     }
-
-    String protocol = url.substring(0, index);
-    if(protocol != "http" && protocol != "https") {
-        DEBUG_HTTPCLIENT("[HTTP-Client][begin] unknown protocol '%s'\n", protocol.c_str());
-        return false;
-    }
-
-    _port = (protocol == "https" ? 443 : 80);
-    return beginInternal(url, protocol.c_str());
+    return beginInternal(url, nullptr);
 }
 
 /**

From a552dbd616fec221e0d7523e4de3092e05c54619 Mon Sep 17 00:00:00 2001
From: Christopher Liebman <liebman@zod.com>
Date: Sat, 29 Sep 2018 17:18:40 -0700
Subject: [PATCH 3/9] fix indentation for style check

---
 .../examples/HTTPRedirect/HTTPRedirect.ino    | 32 +++++++++----------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
index 5109e13f64..dce7605a69 100644
--- a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
+++ b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
@@ -20,15 +20,15 @@ ESP8266WiFiMulti WiFiMulti;
 
 void setup() {
 
-    Serial.begin(115200);
+  Serial.begin(115200);
   // Serial.setDebugOutput(true);
-    Serial.println();
-    Serial.println();
-    Serial.println();
+  Serial.println();
+  Serial.println();
+  Serial.println();
 
   for (uint8_t t = 10; t > 0; t--) {
-      Serial.printf("[SETUP] WAIT %d...\n", t);
-      Serial.flush();
+    Serial.printf("[SETUP] WAIT %d...\n", t);
+    Serial.flush();
     delay(1000);
   }
 
@@ -60,20 +60,20 @@ void loop() {
 
     // As long as we get redirects, follow them
     while(httpCode == 301 || httpCode == 302 || httpCode == 307) {
-        String location = http.header("Location");
-        Serial.printf("[HTTP] redirect(%d): %s\n", httpCode, location.c_str());
-        http.end();
-        if (!http.setURL(location)) {
-            Serial.printf("[HTTP] Bad redirect location: '%s'", location.c_str());
-            return;
-        }
-        httpCode = http.GET();
+      String location = http.header("Location");
+      Serial.printf("[HTTP] redirect(%d): %s\n", httpCode, location.c_str());
+      http.end();
+      if (!http.setURL(location)) {
+        Serial.printf("[HTTP] Bad redirect location: '%s'", location.c_str());
+        return;
+      }
+      httpCode = http.GET();
     }
 
     // httpCode will be negative on error
     if (httpCode > 0) {
       // HTTP header has been send and Server response header has been handled
-        Serial.printf("[HTTP] GET... httpCode: %d\n", httpCode);
+      Serial.printf("[HTTP] GET... httpCode: %d\n", httpCode);
 
       // file found at server
       if (httpCode == HTTP_CODE_OK) {
@@ -81,7 +81,7 @@ void loop() {
         Serial.println(payload);
       }
     } else {
-        Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
+      Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
     }
 
     http.end();

From ac453c3d1e20e56404df56a0884256ed5ebb9b44 Mon Sep 17 00:00:00 2001
From: Christopher Liebman <liebman@zod.com>
Date: Sat, 29 Sep 2018 18:05:57 -0700
Subject: [PATCH 4/9] add space after while for style check

---
 .../ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino    | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
index dce7605a69..86b5192e97 100644
--- a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
+++ b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
@@ -59,7 +59,7 @@ void loop() {
     int httpCode = http.GET();
 
     // As long as we get redirects, follow them
-    while(httpCode == 301 || httpCode == 302 || httpCode == 307) {
+    while (httpCode == 301 || httpCode == 302 || httpCode == 307) {
       String location = http.header("Location");
       Serial.printf("[HTTP] redirect(%d): %s\n", httpCode, location.c_str());
       http.end();

From 686ae0709d835d113c319e1779096edc0597cb1b Mon Sep 17 00:00:00 2001
From: Christopher Liebman <liebman@zod.com>
Date: Thu, 1 Nov 2018 10:06:23 -0700
Subject: [PATCH 5/9] don't use deprecated begin method in redirect example

---
 .../ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino   | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
index 86b5192e97..d733f265cc 100644
--- a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
+++ b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
@@ -41,6 +41,7 @@ void loop() {
   // wait for WiFi connection
   if ((WiFiMulti.run() == WL_CONNECTED)) {
 
+    WiFiClient client;
     HTTPClient http;
 
     // we need the Location header to handle redirects
@@ -52,7 +53,7 @@ void loop() {
 
     Serial.print("[HTTP] begin...\n");
     // configure url
-    http.begin("http://jigsaw.w3.org/HTTP/300/307.html"); //HTTP
+    http.begin(client, "http://jigsaw.w3.org/HTTP/300/307.html"); //HTTP
 
     Serial.print("[HTTP] GET...\n");
     // start connection and send HTTP header

From 4e62aec8b1f1b7fa9d4939565b8bda79de1f4b09 Mon Sep 17 00:00:00 2001
From: Christopher Liebman <liebman@zod.com>
Date: Sun, 4 Nov 2018 06:09:02 -0800
Subject: [PATCH 6/9] moved redirect handling code to HTTPClient. only GET and
 HEAD requests are currently handled automatically Redirects that fail to be
 automatically handled return the redirect code as before

---
 .../examples/HTTPRedirect/HTTPRedirect.ino    |  92 ---------------
 .../src/ESP8266HTTPClient.cpp                 | 105 ++++++++++++++----
 .../ESP8266HTTPClient/src/ESP8266HTTPClient.h |  10 +-
 .../src/ESP8266httpUpdate.cpp                 |  16 +--
 4 files changed, 96 insertions(+), 127 deletions(-)
 delete mode 100644 libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino

diff --git a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino b/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
deleted file mode 100644
index d733f265cc..0000000000
--- a/libraries/ESP8266HTTPClient/examples/HTTPRedirect/HTTPRedirect.ino
+++ /dev/null
@@ -1,92 +0,0 @@
-/**
-   HTTPRedirect.ino
-
-    Created on: 29-Sep-2018
-
-*/
-
-#include <Arduino.h>
-
-#include <ESP8266WiFi.h>
-#include <ESP8266WiFiMulti.h>
-#include <ESP8266HTTPClient.h>
-
-#define WIFI_SSID "SSID"
-#define WIFI_PASS "Password"
-
-
-ESP8266WiFiMulti WiFiMulti;
-
-
-void setup() {
-
-  Serial.begin(115200);
-  // Serial.setDebugOutput(true);
-  Serial.println();
-  Serial.println();
-  Serial.println();
-
-  for (uint8_t t = 10; t > 0; t--) {
-    Serial.printf("[SETUP] WAIT %d...\n", t);
-    Serial.flush();
-    delay(1000);
-  }
-
-  WiFi.mode(WIFI_STA);
-  WiFiMulti.addAP(WIFI_SSID, WIFI_PASS);
-
-}
-
-void loop() {
-  // wait for WiFi connection
-  if ((WiFiMulti.run() == WL_CONNECTED)) {
-
-    WiFiClient client;
-    HTTPClient http;
-
-    // we need the Location header to handle redirects
-    const char * headerkeys[] = { "Location" };
-    size_t headerkeyssize = sizeof(headerkeys) / sizeof(char*);
-
-    // track these headers
-    http.collectHeaders(headerkeys, headerkeyssize);
-
-    Serial.print("[HTTP] begin...\n");
-    // configure url
-    http.begin(client, "http://jigsaw.w3.org/HTTP/300/307.html"); //HTTP
-
-    Serial.print("[HTTP] GET...\n");
-    // start connection and send HTTP header
-    int httpCode = http.GET();
-
-    // As long as we get redirects, follow them
-    while (httpCode == 301 || httpCode == 302 || httpCode == 307) {
-      String location = http.header("Location");
-      Serial.printf("[HTTP] redirect(%d): %s\n", httpCode, location.c_str());
-      http.end();
-      if (!http.setURL(location)) {
-        Serial.printf("[HTTP] Bad redirect location: '%s'", location.c_str());
-        return;
-      }
-      httpCode = http.GET();
-    }
-
-    // httpCode will be negative on error
-    if (httpCode > 0) {
-      // HTTP header has been send and Server response header has been handled
-      Serial.printf("[HTTP] GET... httpCode: %d\n", httpCode);
-
-      // file found at server
-      if (httpCode == HTTP_CODE_OK) {
-        String payload = http.getString();
-        Serial.println(payload);
-      }
-    } else {
-      Serial.printf("[HTTP] GET... failed, error: %s\n", http.errorToString(httpCode).c_str());
-    }
-
-    http.end();
-  }
-
-  delay(10000);
-}
diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index 8daa71b0d5..7d76f7e44f 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -136,6 +136,8 @@ void HTTPClient::clear()
     _size = -1;
     _headers = "";
     _payload.reset();
+    _location = "";
+    _redirectCount = 0;
 }
 
 
@@ -413,7 +415,7 @@ void HTTPClient::end(void)
  * disconnect
  * close the TCP socket
  */
-void HTTPClient::disconnect()
+void HTTPClient::disconnect(bool preserveClient)
 {
     if(connected()) {
         if(_client->available() > 0) {
@@ -429,7 +431,9 @@ void HTTPClient::disconnect()
             DEBUG_HTTPCLIENT("[HTTP-Client][end] tcp stop\n");
             if(_client) {
                 _client->stop();
-                _client = nullptr;
+                if (!preserveClient) {
+                    _client = nullptr;
+                }
             }
 #ifdef HTTPCLIENT_1_1_COMPATIBLE
             if(_tcpDeprecated) {
@@ -518,13 +522,39 @@ void HTTPClient::setTimeout(uint16_t timeout)
  */
 bool HTTPClient::setURL(String url)
 {
+    // TBD: handle redirect with only the path component....
+    // if the new location is only a path then only update the URI
+    // TBD: If reuse is not set then we need to close the connection
+    //if (_location.startsWith("/")) {
+    //    _uri = _location;
+    //    clear();
+    //    return true;
+    //}
+
     if (!url.startsWith(_protocol + ":")) {
         DEBUG_HTTPCLIENT("[HTTP-Client][setURL] new URL not the same protocol, expected '%s', URL: '%s'\n", _protocol.c_str(), url.c_str());
         return false;
     }
+    // disconnect but preserve _client
+    disconnect(true);
+    clear();
     return beginInternal(url, nullptr);
 }
 
+/**
+ * set true to follow redirects.
+ * @param follow
+ */
+void HTTPClient::setFollowRedirects(bool follow)
+{
+    _followRedirects = follow;
+}
+
+void HTTPClient::setRedirectLimit(uint16_t limit)
+{
+    _redirectLimit = limit;
+}
+
 /**
  * use HTTP1.0
  * @param timeout
@@ -607,29 +637,62 @@ int HTTPClient::sendRequest(const char * type, String payload)
  */
 int HTTPClient::sendRequest(const char * type, uint8_t * payload, size_t size)
 {
-    // connect to server
-    if(!connect()) {
-        return returnError(HTTPC_ERROR_CONNECTION_REFUSED);
-    }
+    bool redirect = false;
+    int code = 0;
+    do {
+        redirect = false;
+        DEBUG_HTTPCLIENT("[HTTP-Client][sendRequest] type: '%s' redirCount: %d\n", type, _redirectCount);
+
+        // connect to server
+        if(!connect()) {
+            return returnError(HTTPC_ERROR_CONNECTION_REFUSED);
+        }
 
-    if(payload && size > 0) {
-        addHeader(F("Content-Length"), String(size));
-    }
+        if(payload && size > 0) {
+            addHeader(F("Content-Length"), String(size));
+        }
 
-    // send Header
-    if(!sendHeader(type)) {
-        return returnError(HTTPC_ERROR_SEND_HEADER_FAILED);
-    }
+        // send Header
+        if(!sendHeader(type)) {
+            return returnError(HTTPC_ERROR_SEND_HEADER_FAILED);
+        }
 
-    // send Payload if needed
-    if(payload && size > 0) {
-        if(_client->write(&payload[0], size) != size) {
-            return returnError(HTTPC_ERROR_SEND_PAYLOAD_FAILED);
+        // send Payload if needed
+        if(payload && size > 0) {
+            if(_client->write(&payload[0], size) != size) {
+                return returnError(HTTPC_ERROR_SEND_PAYLOAD_FAILED);
+            }
         }
-    }
+
+        // handle Server Response (Header)
+        code = handleHeaderResponse();
+
+        //
+        // We can follow redirects for 301/302/307 for GET and HEAD requests and
+        // and we have not exceeded the redirect limit. (prevent infinite loop.
+        //
+        // https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
+        //
+        if (_followRedirects &&
+                (_redirectCount < _redirectLimit) &&
+                (code == 301 || code == 302 || code == 307) &&
+                (_location.length() > 0) &&
+                (!strcmp(type, "GET") || !strcmp(type, "HEAD"))) {
+            _redirectCount += 1; // increment the count for redirect.
+            redirect = true;
+            DEBUG_HTTPCLIENT("[HTTP-Client][sendRequest] following redirect:: '%s' redirCount: %d\n", _location.c_str(), _redirectCount);
+            if (!setURL(_location)) {
+                // return the redirect instead of handling on failure of setURL()
+                redirect = false;
+            }
+        }
+
+    } while (redirect);
+
+    // TBD: handle 303 redirect for non GET/HEAD by changing to GET and requesting
 
     // handle Server Response (Header)
-    return returnError(handleHeaderResponse());
+    return returnError(code);
 }
 
 /**
@@ -1191,6 +1254,10 @@ int HTTPClient::handleHeaderResponse()
                     transferEncoding = headerValue;
                 }
 
+                if(headerName.equalsIgnoreCase("Location")) {
+                    _location = headerValue;
+                }
+
                 for(size_t i = 0; i < _headerKeysCount; i++) {
                     if(_currentHeaders[i].key.equalsIgnoreCase(headerName)) {
                         if (_currentHeaders[i].value != "") {
diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
index 2ddc273e65..f6d20d02ba 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.h
@@ -171,6 +171,8 @@ class HTTPClient
     void setAuthorization(const char * user, const char * password);
     void setAuthorization(const char * auth);
     void setTimeout(uint16_t timeout);
+    void setFollowRedirects(bool follow);
+    void setRedirectLimit(uint16_t limit); // max redirects to follow for a single request
     bool setURL(String url); // handy for handling redirects
     void useHTTP10(bool usehttp10 = true);
 
@@ -198,12 +200,12 @@ class HTTPClient
 
 
     int getSize(void);
+    const String& getLocation(void); // Location header from redirect if 3XX
 
     WiFiClient& getStream(void);
     WiFiClient* getStreamPtr(void);
     int writeToStream(Stream* stream);
     const String& getString(void);
-
     static String errorToString(int error);
 
 protected:
@@ -213,7 +215,7 @@ class HTTPClient
     };
 
     bool beginInternal(String url, const char* expectedProtocol);
-    void disconnect();
+    void disconnect(bool preserveClient = false);
     void clear();
     int returnError(int error);
     bool connect(void);
@@ -248,6 +250,10 @@ class HTTPClient
     int _returnCode = 0;
     int _size = -1;
     bool _canReuse = false;
+    bool _followRedirects = false;
+    uint16_t _redirectCount = 0;
+    uint16_t _redirectLimit = 10;
+    String _location;
     transferEncoding_t _transferEncoding = HTTPC_TE_IDENTITY;
     std::unique_ptr<StreamString> _payload;
 };
diff --git a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
index a0326311dd..bc599f84bf 100644
--- a/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
+++ b/libraries/ESP8266httpUpdate/src/ESP8266httpUpdate.cpp
@@ -261,6 +261,7 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
     // use HTTP/1.0 for update since the update handler not support any transfer Encoding
     http.useHTTP10(true);
     http.setTimeout(_httpClientTimeout);
+    http.setFollowRedirects(_followRedirects);
     http.setUserAgent(F("ESP8266-http-Update"));
     http.addHeader(F("x-ESP8266-STA-MAC"), WiFi.macAddress());
     http.addHeader(F("x-ESP8266-AP-MAC"), WiFi.softAPmacAddress());
@@ -280,7 +281,7 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
         http.addHeader(F("x-ESP8266-version"), currentVersion);
     }
 
-    const char * headerkeys[] = { "x-MD5" , "Location"};
+    const char * headerkeys[] = { "x-MD5" };
     size_t headerkeyssize = sizeof(headerkeys) / sizeof(char*);
 
     // track these headers
@@ -288,19 +289,6 @@ HTTPUpdateResult ESP8266HTTPUpdate::handleUpdate(HTTPClient& http, const String&
 
 
     int code = http.GET();
-    while(_followRedirects && (code == 302 || code == 301))
-    {
-        String location = http.header("Location");
-        DEBUG_HTTP_UPDATE("[httpUpdate] HTTP redirect(%d): %s\n", code, location.c_str());
-        http.end();
-        if (!http.setURL(location))
-        {
-            DEBUG_HTTP_UPDATE("[httpUpdate] Bad redirect location: '%s'", location.c_str());
-            _lastError = code;
-            return HTTP_UPDATE_FAILED;
-        }
-        code = http.GET();
-    }
     int len = http.getSize();
 
     if(code <= 0) {

From ca8c891cf362f084c7eb59f4459c1092e1c7667d Mon Sep 17 00:00:00 2001
From: Chris Liebman <chris.l@taboola.com>
Date: Wed, 7 Nov 2018 17:52:14 -0800
Subject: [PATCH 7/9] added support for POST/303 redirect added device redirect
 tests

---
 .../src/ESP8266HTTPClient.cpp                 |  28 ++++-
 .../test_http_client/test_http_client.ino     | 103 +++++++++++++++++-
 .../test_http_client/test_http_client.py      |  19 +++-
 3 files changed, 143 insertions(+), 7 deletions(-)

diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index 6b6bdac06b..f7bab69063 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -640,6 +640,13 @@ int HTTPClient::sendRequest(const char * type, uint8_t * payload, size_t size)
     bool redirect = false;
     int code = 0;
     do {
+        // wipe out any existing headers from previous request
+        for(size_t i = 0; i < _headerKeysCount; i++) {
+            if (_currentHeaders[i].value.length() > 0) {
+                _currentHeaders[i].value = "";
+            }
+        }
+
         redirect = false;
         DEBUG_HTTPCLIENT("[HTTP-Client][sendRequest] type: '%s' redirCount: %d\n", type, _redirectCount);
 
@@ -669,15 +676,17 @@ int HTTPClient::sendRequest(const char * type, uint8_t * payload, size_t size)
 
         //
         // We can follow redirects for 301/302/307 for GET and HEAD requests and
-        // and we have not exceeded the redirect limit. (prevent infinite loop.
+        // and we have not exceeded the redirect limit preventing an infinite
+        // redirect loop.
         //
         // https://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html
         //
         if (_followRedirects &&
                 (_redirectCount < _redirectLimit) &&
-                (code == 301 || code == 302 || code == 307) &&
                 (_location.length() > 0) &&
-                (!strcmp(type, "GET") || !strcmp(type, "HEAD"))) {
+                (code == 301 || code == 302 || code == 307) &&
+                (!strcmp(type, "GET") || !strcmp(type, "HEAD"))
+                ) {
             _redirectCount += 1; // increment the count for redirect.
             redirect = true;
             DEBUG_HTTPCLIENT("[HTTP-Client][sendRequest] following redirect:: '%s' redirCount: %d\n", _location.c_str(), _redirectCount);
@@ -689,7 +698,18 @@ int HTTPClient::sendRequest(const char * type, uint8_t * payload, size_t size)
 
     } while (redirect);
 
-    // TBD: handle 303 redirect for non GET/HEAD by changing to GET and requesting
+    // handle 303 redirect for non GET/HEAD by changing to GET and requesting new url
+    if (_followRedirects &&
+            (_redirectCount < _redirectLimit) &&
+            (_location.length() > 0) &&
+            (code == 303) &&
+            strcmp(type, "GET") && strcmp(type, "HEAD")
+            ) {
+        _redirectCount += 1;
+        if (setURL(_location)) {
+            code = sendRequest("GET");
+        }
+    }
 
     // handle Server Response (Header)
     return returnError(code);
diff --git a/tests/device/test_http_client/test_http_client.ino b/tests/device/test_http_client/test_http_client.ino
index 12aefd2b54..d666fb9556 100644
--- a/tests/device/test_http_client/test_http_client.ino
+++ b/tests/device/test_http_client/test_http_client.ino
@@ -64,9 +64,110 @@ TEST_CASE("HTTP GET & POST requests", "[HTTPClient]")
         REQUIRE(httpCode == HTTPC_ERROR_CONNECTION_REFUSED);
         http.end();
     }
+    {
+        // 301 redirect with follow enabled
+        WiFiClient client;
+        HTTPClient http;
+        http.setFollowRedirects(true);
+        String uri = String("/redirect301?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == HTTP_CODE_OK);
+        String payload = http.getString();
+        REQUIRE(payload == "redirect success");
+    }
+    {
+        // 301 redirect with follow disabled
+        WiFiClient client;
+        HTTPClient http;
+        String uri = String("/redirect301?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == 301);
+    }
+    {
+        // 302 redirect with follow enabled
+        WiFiClient client;
+        HTTPClient http;
+        http.setFollowRedirects(true);
+        String uri = String("/redirect302?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == HTTP_CODE_OK);
+        String payload = http.getString();
+        REQUIRE(payload == "redirect success");
+    }
+    {
+        // 302 redirect with follow disabled
+        WiFiClient client;
+        HTTPClient http;
+        String uri = String("/redirect302?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == 302);
+    }
+    {
+        // 307 redirect with follow enabled
+        WiFiClient client;
+        HTTPClient http;
+        http.setFollowRedirects(true);
+        String uri = String("/redirect307?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == HTTP_CODE_OK);
+        String payload = http.getString();
+        REQUIRE(payload == "redirect success");
+    }
+    {
+        // 307 redirect with follow disabled
+        WiFiClient client;
+        HTTPClient http;
+        String uri = String("/redirect307?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == 307);
+    }
+    {
+        // 301 exceeding redirect limit
+        WiFiClient client;
+        HTTPClient http;
+        http.setFollowRedirects(true);
+        http.setRedirectLimit(0);
+        String uri = String("/redirect301?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == 301);
+    }
+    {
+        // POST 303 redirect with follow enabled
+        WiFiClient client;
+        HTTPClient http;
+        http.setFollowRedirects(true);
+        http.begin(client, getenv("SERVER_IP"), 8088, "/redirect303");
+        auto httpCode = http.POST(getenv("SERVER_IP"));
+        REQUIRE(httpCode == HTTP_CODE_OK);
+        String payload = http.getString();
+        REQUIRE(payload == "redirect success");
+    }
+    {
+        // POST 303 redirect with follow disabled
+        WiFiClient client;
+        HTTPClient http;
+        http.begin(client, getenv("SERVER_IP"), 8088, "/redirect303");
+        auto httpCode = http.POST(getenv("SERVER_IP"));
+        REQUIRE(httpCode == 303);
+    }
+    {
+        // 302 redirect with follow disabled
+        WiFiClient client;
+        HTTPClient http;
+        String uri = String("/redirect302?host=")+getenv("SERVER_IP");
+        http.begin(client, getenv("SERVER_IP"), 8088, uri.c_str());
+        auto httpCode = http.GET();
+        REQUIRE(httpCode == 302);
+    }
 }
 
-
 TEST_CASE("HTTPS GET request", "[HTTPClient]")
 {
     //
diff --git a/tests/device/test_http_client/test_http_client.py b/tests/device/test_http_client/test_http_client.py
index a78d4108df..d991ca985a 100644
--- a/tests/device/test_http_client/test_http_client.py
+++ b/tests/device/test_http_client/test_http_client.py
@@ -1,5 +1,5 @@
 from mock_decorators import setup, teardown
-from flask import Flask, request
+from flask import Flask, request, redirect
 from threading import Thread
 import urllib2
 import os
@@ -26,6 +26,21 @@ def root():
     def get_data():
         size = int(request.args['size'])
         return 'a'*size
+    @app.route("/target")
+    def target():
+        return "redirect success"
+    @app.route("/redirect301")
+    def redirect301():
+        return redirect("http://{}:8088/target".format(request.args['host']), code=301)
+    @app.route("/redirect302")
+    def redirect302():
+        return redirect("http://{}:8088/target".format(request.args['host']), code=302)
+    @app.route("/redirect303", methods = ['POST'])
+    def redirect303():
+        return redirect("http://{}:8088/target".format(request.data), code=303)
+    @app.route("/redirect307")
+    def redirect307():
+        return redirect("http://{}:8088/target".format(request.args['host']), code=307)
     def flaskThread():
         app.run(host='0.0.0.0', port=8088)    
     th = Thread(target=flaskThread)
@@ -35,7 +50,7 @@ def flaskThread():
 def teardown_http_get(e):
     response = urllib2.urlopen('http://localhost:8088/shutdown')
     html = response.read()
-    time.sleep(30)
+    time.sleep(1) # avoid address in use error on macOS
 
 
 @setup('HTTPS GET request')

From 12f7ad70fc22e6c84dfd589736a9ba9c458120fd Mon Sep 17 00:00:00 2001
From: Chris Liebman <chris.l@taboola.com>
Date: Wed, 7 Nov 2018 18:40:36 -0800
Subject: [PATCH 8/9] add missing getLocation() implementation

---
 libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index f7bab69063..1549a681ea 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -863,6 +863,14 @@ int HTTPClient::getSize(void)
     return _size;
 }
 
+/**
+ * Location if redirect
+ */
+const String& HTTPClient::getLocation(void)
+{
+    return _location;
+}
+
 /**
  * returns the stream of the tcp connection
  * @return WiFiClient

From e9a2c234508f5196391eb4912a17f08bfd990656 Mon Sep 17 00:00:00 2001
From: Chris Liebman <chris.l@taboola.com>
Date: Sun, 3 Feb 2019 10:22:15 -0800
Subject: [PATCH 9/9] if the new location is only a path then only update the
 URI

---
 .../ESP8266HTTPClient/src/ESP8266HTTPClient.cpp    | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
index d1d206c9db..2c9542cb03 100644
--- a/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
+++ b/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp
@@ -140,7 +140,6 @@ void HTTPClient::clear()
     _headers = "";
     _payload.reset();
     _location = "";
-    _redirectCount = 0;
 }
 
 
@@ -412,6 +411,7 @@ void HTTPClient::end(void)
 {
     disconnect();
     clear();
+    _redirectCount = 0;
 }
 
 /**
@@ -525,14 +525,12 @@ void HTTPClient::setTimeout(uint16_t timeout)
  */
 bool HTTPClient::setURL(String url)
 {
-    // TBD: handle redirect with only the path component....
     // if the new location is only a path then only update the URI
-    // TBD: If reuse is not set then we need to close the connection
-    //if (_location.startsWith("/")) {
-    //    _uri = _location;
-    //    clear();
-    //    return true;
-    //}
+    if (_location.startsWith("/")) {
+        _uri = _location;
+        clear();
+        return true;
+    }
 
     if (!url.startsWith(_protocol + ":")) {
         DEBUG_HTTPCLIENT("[HTTP-Client][setURL] new URL not the same protocol, expected '%s', URL: '%s'\n", _protocol.c_str(), url.c_str());