Using client.send() outside the loop (FireFox client incompatibility)

[xgarb]

Hi. This might be more of a programming question again but...

Something like this works:

void delete_all_faces() {
  delete_face_all_in_flash_with_name(&st_face_list);
}
void handle_message(WebsocketsMessage msg) {
  if (msg.data() == "delete_all") {
    delete_all_faces();
    g_state = DELETE_ALL;
  }
}
void loop() {
   auto client = socket_server.accept();
   client.onMessage(handle_message);
   while (client.available()) {
      client.poll();
      switch (g_state) {
         case DELETE_ALL:
         client.send("All Faces Deleted");
         break;
         case ...
      }
   }
}

But I would prefer to send the message from the delete_all_faces function something like this...

void delete_all_faces() {
  delete_face_all_in_flash_with_name(&st_face_list);
  client.send("All Faces Deleted");
}
void handle_message(WebsocketsMessage msg) {
  if (msg.data() == "delete_all") {
    delete_all_faces();
  }
}
void loop() {
  auto client = socket_server.accept();
  client.onMessage(handle_message);
  while (client.available()) {
    ...
  }
}

Is it possible to make 'client' accessible outside the loop?

[gilmaimon]

Yes it is possible, and even very easy. Message callbacks come in 2 forms, you use the shorter one but if you wish to also accept the client as parameter to handle_message, you can. Look here

After you get the client as parameter in handle_message, passing it over to delete_all_faces() is simple (pass as reference)

[xgarb]

Like this? (I've cut non relevant code) It works, but I'm not sure I've done it correctly.

static esp_err_t send_face_list(WebsocketsClient &client)
{
  face_id_node *head = st_face_list.head;
  char face[64];
  for (int i = 0; i < st_face_list.count; i++)
  {
    sprintf(face, "facelist:%s", head->id_name);
    client.send(face);
    head = head->next;
  }
}

static esp_err_t delete_all_faces(WebsocketsClient &client)
{
  delete_face_all_in_flash_with_name(&st_face_list);
  client.send("update_faces");
}

void handle_message(WebsocketsClient &client, WebsocketsMessage msg)
{
  if (msg.data() == "detect") {
    client.send("DETECTING");
  }
  if (msg.data() == "delete_all") {
    delete_all_faces(client);
  }

}

void loop() {
  auto client = socket_server.accept();
  client.onMessage(handle_message);
  while (client.available()) {
    client.poll();
	if (left_sample_face == 0)
	{
		send_face_list(client);
	}
	client.send("NO FACE DETECTED");
	}
}

[gilmaimon]

Looks good to me 👍

[xgarb]

This is the project - https://robotzero.one/esp-who-recognition-with-names/ I need to make some improvements to the tutorial

I noticed that it doesn't work in Firefox. I get a cannot connect to ws//... error. If you're interested in testing your library with one of the ESP32 cameras I'll buy one for you.

[gilmaimon]

There is no need to buy me anything, thank you.

Can you elaborate on what's not working? In what manners do things fail? How can I re-produce? Are you able to re-produce without a camera (just by sending very long messages)?
What software do you use as server (what do you mean by Firefox, a Firefox ws client?)
Have you turned on board logs to see what fails? Do you use the latest library version?

[xgarb]

I've tried with 0.4.0. and 0.4.2 and this code in a web page:

document.addEventListener("DOMContentLoaded", function(event) {
  var baseHost = document.location.origin;
  var streamUrl = baseHost + ":81";
  const WS_URL = "ws://" + window.location.host + ":82";
  const ws = new WebSocket(WS_URL);
  ....
}

gives a Firefox can't establish a connection to the server at ws://192.168.1.108:82/. error

Cut down ESP32 code:

#include <ArduinoWebsockets.h>
#include "esp_http_server.h"
#include <WiFi.h>
#include "camera_index.h"

const char* ssid = "NSA ";
const char* password = "";

using namespace websockets;
WebsocketsServer socket_server;
httpd_handle_t camera_httpd = NULL;

void setup() {
  Serial.begin(115200);
 
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("WiFi connected");

  app_httpserver_init();
  socket_server.listen(82);

  Serial.print("Camera Ready! Use 'http://");
  Serial.print(WiFi.localIP());
  Serial.println("' to connect");
}

static esp_err_t index_handler(httpd_req_t *req) {
  httpd_resp_set_type(req, "text/html");
  httpd_resp_set_hdr(req, "Content-Encoding", "gzip");
  return httpd_resp_send(req, (const char *)index_ov2640_html_gz, index_ov2640_html_gz_len);
}



httpd_uri_t index_uri = {
  .uri       = "/",
  .method    = HTTP_GET,
  .handler   = index_handler,
  .user_ctx  = NULL
};

void app_httpserver_init ()
{
  httpd_config_t config = HTTPD_DEFAULT_CONFIG();
  if (httpd_start(&camera_httpd, &config) == ESP_OK)
    Serial.println("httpd_start");
  {
    httpd_register_uri_handler(camera_httpd, &index_uri);
  }
}

void handle_message(WebsocketsClient &client, WebsocketsMessage msg)
{
}

void loop() {
  auto client = socket_server.accept();
  client.onMessage(handle_message);
}

Works great in Chrome. All the communication after the page loads is done with Websockets: https://vimeo.com/338402026

[gilmaimon]

Thank you for the details! This definitely looks like a big with my implementation of websockets that FireFox does not want to accept (maybe chrome doesn't care).
I will try to re-produce this weekend, if I will be able to I will probably open a new issue about it with a more specific name.
Can you write down your FireFox version, just in case?

Thanks

[xgarb]

Firefox is 67 (64 bit) on Win 10.
Same with the Developer Edition 68.0b6
Thanks.

[gilmaimon]

I found and fixed the issue. Patch 0.4.3 is now released. Thank you for the error reporting and details.
Please make sure this works for you, so I can consider this issue resolved.

Gil.

[xgarb]

New problem with .4.3 and .4.4 with Chrome and Firefox. The send binary part of the script (that sends video frames) is crashing:

[D][WiFiClient.cpp:482] connected(): Disconnected: RES: 0, ERR: 128
[E][WiFiClient.cpp:365] write(): fail on fd 63, errno: 11, "No more processes"
[E][WiFiClient.cpp:365] write(): fail on fd 63, errno: 11, "No more processes"
[E][WiFiClient.cpp:365] write(): fail on fd 63, errno: 11, "No more processes"
[E][WiFiClient.cpp:365] write(): fail on fd 63, errno: 11, "No more processes"
[E][WiFiClient.cpp:365] write(): fail on fd 63, errno: 11, "No more processes"
abort() was called at PC 0x40136eeb on core 1

Backtrace: 0x40091408:0x3ffb1d20 0x40091639:0x3ffb1d40 0x40136eeb:0x3ffb1d60 0x40136f32:0x3ffb1d80 0x401362bf:0x3ffb1da0 0x401363ae:0x3ffb1dc0 0x40136365:0x3ffb1de0 0x400d575b:0x3ffb1e00 0x400d57b6:0x3ffb1e30 0x400d4b8a:0x3ffb1e60 0x400d3339:0x3ffb1e80 0x400d9be9:0x3ffb1fb0 0x4008d3a5:0x3ffb1fd0

Rebooting...

Decoding stack results
0x40091408: invoke_abort at /Users/ficeto/Desktop/ESP32/ESP32/esp-idf-public/components/esp32/panic.c line 155
0x40091639: abort at /Users/ficeto/Desktop/ESP32/ESP32/esp-idf-public/components/esp32/panic.c line 170
0x40136eeb: __cxxabiv1::__terminate(void ()()) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_terminate.cc line 47
0x40136f32: std::terminate() at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_terminate.cc line 57
0x401362bf: __cxxabiv1::__cxa_throw(void, std::type_info*, void ()(void)) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/eh_throw.cc line 87
0x401363ae: operator new(unsigned int) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/new_op.cc line 54
0x40136365: operator new[](unsigned int) at /builds/idf/crosstool-NG/.build/src/gcc-5.2.0/libstdc++-v3/libsupc++/new_opv.cc line 32
0x400d575b: websockets::internals::WebsocketsEndpoint::send(char const*, unsigned int, unsigned char, bool, bool, char const*) at C:\Users\Dude\Documents\Arduino\libraries\ArduinoWebsockets\src\websockets_endpoint.cpp line 367
0x400d57b6: websockets::internals::WebsocketsEndpoint::send(char const*, unsigned int, unsigned char, bool) at C:\Users\Dude\Documents\Arduino\libraries\ArduinoWebsockets\src\websockets_endpoint.cpp line 321
0x400d4b8a: websockets::WebsocketsClient::sendBinary(char const*, unsigned int) at C:\Users\Dude\Documents\Arduino\libraries\ArduinoWebsockets\src\websockets_client.cpp line 396
0x400d3339: loop() at C:\Users\Dude\Documents\Arduino\CameraWebServerWeChatWebSockets/CameraWebServerWeChatWebSockets.ino line 358
0x400d9be9: loopTask(void*) at C:\Users\Dude\Documents\ArduinoData\packages\esp32\hardware\esp32\1.0.3-rc1\cores\esp32\main.cpp line 19
0x4008d3a5: vPortTaskWrapper at /Users/ficeto/Desktop/ESP32/ESP32/esp-idf-public/components/freertos/port.c line 143

[gilmaimon]

Can you try reverting to version 0.4.2 to see if it is an error in the library or in something external (WiFiClient for example)?