WebServer - HTTP request headers array contains only 1 element

[jordanj-pl]

Hardware:

Board: ESP32 Dev Module
Core Installation version: 1.0.4
IDE name: Arduino IDE
Flash Frequency: 80Mhz
PSRAM enabled: ?no? ?yes?
Upload Speed: 115200
Computer OS: Mac OSX

Description:

I am trying to read HTTP headers from request. The array always contain 1 element regardless actual number of headers sent with request. Exemplary code is below:

Please note the interesting thing. When printing array of headers only 1 item is available i.e. Authorization but when trying to access Host header by method hostHeader() it returns valid value.

class HTTPServer {

  private:
    WebServer *server;

public:
HTTPServer() {
      this->server = new WebServer(80);
      this->server->begin();

      this->server->on("/aaatest", [this]() {

        int argsNum = this->server->args();
        for(int i=0; i<argsNum; i++) {
          Serial.println(this->server->argName(i) + " : " + this->server->arg(i));
        }
        
        int headersNum = this->server->headers();
        Serial.println("Headers num: " + String(headersNum));
        Serial.println("Header [Accept]: " + this->server->header("Accept"));
        Serial.println("Header [Host]: " + this->server->hostHeader());
        Serial.println(this->server->hasHeader("Accept"));
        for(int i=0; i<headersNum; i++) {
          Serial.println(this->server->headerName(i) + " : " + this->server->header(i));
        }

      });

}


}

Here is the result:

00:38:25.359 -> Headers num: 1
00:38:25.359 -> Header [Accept]: 
00:38:25.359 -> Header [Host]: 10.0.0.165
00:38:25.359 -> 0
00:38:25.359 -> Authorization : 

[stale]

[STALE_SET] This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 14 days if no further activity occurs. Thank you for your contributions.

[stale]

[STALE_DEL] This stale issue has been automatically closed. Thank you for your contributions.

[TheRealKasumi]

Hey guys, 3 years later this still seems to be an issue or maybe we are using it wrong. I encountered the exact same problem described above with core version 2.0.5.

Looking into this for a few seconds on the side it seems like _headerKeysCount is always 1 when _parseRequest is called in Parsing.cpp. Further down the headers and values are correctly parsed and _collectHeader is called with the header and it's value as parameters:

bool WebServer::_collectHeader(const char *headerName, const char *headerValue)
{
  for (int i = 0; i < _headerKeysCount; i++)
  {
    if (_currentHeaders[i].key.equalsIgnoreCase(headerName))
    {
      _currentHeaders[i].value = headerValue;
      return true;
    }
  }
  return false;
}

However with _headerKeysCount being 1 and _currentHeaders having one element... we are not getting far here.

[TheRealKasumi]

Alright, looking further into this, it doesn't seem to be a bug but is intended like this. Headers are not parsed by default, maybe having memory consumption in mind. The following works:

#include <WebServer.h>

WebServer srv(80);

const char *headerKeys[2] = {"foo", "bar"};
srv.collectHeaders(headerKeys, 2);

// Now when receiving requests the headers above are parsed correctly

It probably would be good to have an example for that. It's not documented I think and can be quite confusing. Reason is, that all args are parsed by default and here the usage is different/unexpected.

[WebDust21]

It probably would be good to have an example for that. It's not documented I think and can be quite confusing.

Goodness sakes, what a lifesaver! Works a treat!
And yes, this is completely undocumented. (Such a shame that the WebServer is not well documented.)

99% of the examples online are for the AsyncWebServer, not the plain-jane WebServer.