redirect location gets cleared in setURL(const String& url) function of ESP8266HTTPClient.cpp

[Suraj151]

i updated to latest release 2.6.0 before my last ota update to devices and now devices are not updating as they do before. i go through debug process where i found subjected issue.

below line return false for redirects in ota update

Arduino/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp

Line 555 in 05454df

return beginInternal(url, nullptr);

so i did serial debug at

bool HTTPClient::setURL(const String& url)
{
    // if the new location is only a path then only update the URI
    if (url && url[0] == '/') {
        _uri = url;
        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
    Serial.printf("check url1: %s\n", url.c_str());
    disconnect(true);
    Serial.printf("check url2: %s\n", url.c_str());
    clear();
    Serial.printf("check url3: %s\n", url.c_str());
    return beginInternal(url, nullptr);
}

and at

bool HTTPClient::beginInternal(const String& __url, const char* expectedProtocol)
{
    String url(__url);

    DEBUG_HTTPCLIENT("[HTTP-Client][begin] url: %s\n", url.c_str());
    clear();
    Serial.printf("check url4: %s\n", url.c_str());
    // check for : (http: or https:
    int index = url.indexOf(':');
    if(index < 0) {
        DEBUG_HTTPCLIENT("[HTTP-Client][begin] failed to parse protocol\n");
        return false;
    }

where i found serial debug output as

check url4: http://something
check url1: http://something
check url2: http://something
check url3: 
check url4: 

and resulted that clear() function clears the location url before pass it to beginInterval function.
don't know much why it is cleared before passing, since beginInterval function calls clear at beginning.
i get it done by commenting clear().

[d-a-v]

@liebman can you please have a look to this issue ?
https://github.com/esp8266/Arduino/blame/master/libraries/ESP8266HTTPClient/src/ESP8266HTTPClient.cpp#L554

[liebman]

OK - this is because the parameter to setURLwas changed to to a const String& in #6571. And given that beginInternal both forces a local copy of the url and calls clear I'll put a PR together that removes the clear just before beginInternal from setURL.