Hi.
Is this question related with this one: https://rntlab.com/question/over-the-air/?
You can have a button that redirects you to another URL that will request another HTML page, or if you don’t want to access the login page again, go directly to the URL that displays another HTML page.
I’m not sure if I really understood your question.
Regards,
Sara

Yes it does. But we will forget about that post. Don’t answer it.

In the Ruis Santos code OTA:
An extra button could call this function?:

server.on(“/serverIndex”, HTTP_GET, []() {
server.sendHeader(“Connection”, “close”);
server.send(200, “text/html”, webPage);
});

———————-
const char *webPage = // to be corrected
“”
“”
“Météo”
“”
“if (atoi(%CELSIUSTEMP%) >= 25)”
“{“
“”
“}”
“else if (atoi(%CELSIUSTEMP%) = 5)”
“{“
“”
“}”
“else if (atoi(%CELSIUSTEMP%) < 5)"
"{"
"”
“}”
“</SCRIPT"
"”
“myDate()”
“”
“PuissanceWifi =  %PUISSANCEWIFI%”
“
Page en ligne pour “
“%WEBPAGETIME%”
” minutes.”
” %CTEMP%”
“°C”
“Humidité du sol:  “
“%VAL1%”
“%,  “
“%VAL2%”
“%”
“Humidité: “
“%HUMIDITYTEMP%”
“%   Rosé: “
“%DEW%”
“°  “
“Ressenti: “
“%HIC%”
“°”
“”
“for (int i = newLinesCnt ; i >= 0 ; i–)”
“{“
“newLinesArray[i]
“
“}”
“
——————————————-
“
“for (int spiffDatas = decCnt; spiffDatas >= 0; spiffDatas–)”
“{“
“if (datArray[spiffDatas] != 0)”
“{“
“
“
“datArray[spiffDatas]”
“
“
“}”
“}”
“”
“”;

Regards,

JPD

Hi.
Yes,
Add something like this in your HTML text:

<p><a href="/serverIndex"><button>YOUR_TEXT_HERE</button></a></p>

It will create a button that when clicked, will redirect to the /serverIndex URL and that function will be called.
Regards,
Sara

Hi,
What does that means:
 
src\main new.cpp: In function 'void setup()':
src\main new.cpp:883:12: error: 'class WiFiServer' has no member named 'on'

server.on(" / webPage", HTTP_GET, []()
^
src\main new.cpp: In lambda function:
src\main new.cpp:885:14: error: 'class WiFiServer' has no member named 'sendHeader'
 
server.on(” / webPage”, HTTP_GET, []()
{
server.sendHeader(“Connection”, “close”);
server.send(200, “text / html”, webPage);
});
 
JPD

Hi.
It means that server that is a WiFiServer object doesn’t have any method called on.
It probably means that you’re not using the right library for that method, or that you don’t have things declared in a proper way.
Regards,
Sara

Hi,
 
I went in the C file , there is method on.
 
I copied paste from the genuine file:
 
#include <WiFi.h>
Used: …\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.3\libraries\WiFi
#include <WiFiClient.h>
#include <WebServer.h>
Used : …\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.3\libraries\WebServer
#include <ESPmDNS.h>
#include <Update.h>
 
#include <WiFiUdp.h>
#include <NTPClient.h>
#include “FS.h”
#include “SPIFFS.h”
#include <time.h>
#include “DHT.h”
 
Regards
 
JPD

So, I don’t know what might be wrong.
Maybe the server object is not defined properly. How do you initialize your server object?
Regards,
Sara

I found something.
It compiles and I can open the web page.
The problem is the processor function witch should replace the %PLACEHOLDER%
This is the one causing the compiler errors.

Start your code here

const char *webPage =
  ""
  ""
  "Météo"
  ""
  "if (atoi(%CELSIUSTEMP%) >= 25)"
  "{"
  ""
  "}"
  "else if (atoi(%CELSIUSTEMP%) = 5)"
  "{"
  ""
  "}"
  "else if (atoi(%CELSIUSTEMP%) < 5)"
  "{"
  ""
  "}"
  "</SCRIPT"
  ""
  "%MYDATE%"
  ""
  "PuissanceWifi =  %PUISSANCEWIFI%"
  "
Page en ligne pour "
  "%WEBPAGETIME%"
  " minutes."
  " %CTEMP%"
  "°C"
  "Humidité du sol:  "
  "%VAL1%"
  "%,  "
  "%VAL2%"
  "%,  "
  "Température du sol:  "
  "%GROUND%"
  "%"
  "Humidité: "
  "%HUMIDITYTEMP%"
  "%   Rosé: "
  "%DEW%"
  "°  "
  "Ressenti: "
  "%HIC%"
  "°"
  ""
  "%MORELINES%"
  ""
  "";

String processor(const String &var)
{
  float t, h, hic, dew;
  int val1, val2;
  float_t pw;
  if (var == "PUISSANCEWIFI")
  {
    pw = WiFi.RSSI();
    return isnan(pw) ? String("Error") : String(pw, 1);
  } else if (var == "CTEMP")
  {
     Read temperature as Celsius (the default)
    t = dht.readTemperature();
    return String(t);
  } else if (var == "VAL1")
  {
    val1 = capacitiveProbe(1, 120, 1, probe1);
    return String(val1);
  } else if (var == "VAL2")
  {
    val2 = capacitiveProbe(1, 120, 1, probe2);
    return String(val2);
  } else if (var == "GROUND")
  {
    ground = fonction
      return String();
  } else if (var == "HUMIDITYTEMP")
  {
    h = dht.readHumidity();
    dtostrf(h, 6, 2, humidityTemp);  ("Decimal to String Float").
    return String(h);
  } else if (var == "HIC")
  {
    hif = dht.computeHeatIndex(f, h);
    hic = dht.computeHeatIndex(t, h, false);
    dtostrf(hic, 6, 2, celsiusTemp);
    return String(hic);
  } else if (var == "DEW")
  {
    dew = dewPoint(t, h);
    return String(dew);
  } else if (var == "MORELINES")
  {
    return moreLines();
  } else if (var == "MYDATE")
  {
    return (myDate());
  }
  return "";
}

Regards,

JPD

Another thing:

Do I have to define the place holders (%PLACEHOLDER%) somewhere?

JPD

Hi again.
Instead of using % for the percentage sign for the humidity unit, use the HTML entity instead: https://www.freeformatter.com/html-entities.html
Regards,
Sara

Hi,

Yet another thing.

The processor method creates the compiling problem. Is it because the method code has flaws?

The parameter receive the webPage const char* webPage?

From which class is that method from?

Could I use a string tokenizer to parse the string parameter and replace the placeholders by their values or does the processor method do the job?

Regards,

JPD

Hi, ;o)

It compiles! With one flaw; see image.
Open image in a new window.

Start your code here
const char *webPage =
  "<!DOCTYPE HTML><html lang='fr'><head><meta name='viewport' content='width=device-width, initial-scale=1'>"
  "<meta http-equiv='refresh' content='30'></head>"
  "<body style='color:#f3d6e1;'><div style='font-size: 3.5rem;color:green;'><p style='text-align:center;'>Météo</p></div>"
  "<script language='Javascript' type='text/javascript'>"
  "if (%CELSIUSTEMP%>= 25){"
  "document.write(\"<div style='color: #930000;'><p style='text-align:center;'>\");"
  "}"
  "else if (%CELSIUSTEMP% < 25 && %CELSIUSTEMP%>= 5){"
  "document.write(\"<div style='color: #006601;'><p style='text-align:center;'>\");"
  "}else if (%CELSIUSTEMP% < 5){"
  "document.write(\"<div style='color: #009191;'>\");"
  "}"
  "</script>"
  "<p style='text-align:center;font-size:14pt;'>"
  "%MYDATE%"
  "</p><p></p><p style='text-align:center;font-size:14pt;'>"
  "PuissanceWifi&nbsp;=&nbsp; %PUISSANCEWIFI%"
  "<br>Page en ligne pour&nbsp;"
  "%WEBPAGETIME%"
  "&nbsp;minutes."
  "</p><p></p><p style='text-align:center;'> %CTEMP%"
  "&deg;C</p>"
  "<p style='text-align:center;'>Humidité du sol:&nbsp;&nbsp;"
  "%VAL1%"
  "%,&nbsp;&nbsp;"
  "%VAL2%"
  "%,&nbsp;&nbsp;"
  "Température du sol:&nbsp;&nbsp;"
  "%GROUND%"
  "%</p>"
  "<p style='text-align:center;font-size:20pt;'>Humidité:&nbsp;"
  "%HUMIDITYTEMP%"
  "%&nbsp;&nbsp;&nbsp;Rosé:&nbsp;"
  "%DEW%"
  "&deg;&nbsp;&nbsp;"
  "Ressenti:&nbsp;"
  "%HIC%"
  "&deg;</p>"
  "<p style='text-align:center;font-size:16pt;'>"
  "%MORELINES%"
  "</p></div>"
  "</body></html>";
String processor(const String &var)
{
  float t=0, h=0, hic, dew;
  int val1, val2, ground;
  float_t pw;
  if (var == "PUISSANCEWIFI")
  {
    pw = WiFi.RSSI();
    return isnan(pw) ? String("Error") : String(pw, 1);
  } else if (var == "CTEMP")
  {
    //Read temperature as Celsius (the default)
    t = dht.readTemperature();
    return String(t);
  } else if (var == "VAL1")
  {
    val1 = capacitiveProbe(1, 120, 1, probe1);
    return String(val1);
  } else if (var == "VAL2")
  {
    val2 = capacitiveProbe(1, 120, 1, probe2);
    return String(val2);
  } else if (var == "GROUND")
  {
    ground = analogRead(GROUND_PIN);	//String(analogRead(0), DEC); String(5.698, 3);
    return String(ground);
  } else if (var == "HUMIDITYTEMP")
  {
    h = dht.readHumidity();
    //dtostrf(h, 6, 2, humidityTemp); // ("Decimal to String Float").
    return String(h);
  } else if (var == "HIC")
  {
    hic = dht.computeHeatIndex(t, h, false);
    //dtostrf(hic, 6, 2, celsiusTemp);
    return String(hic);
  } else if (var == "DEW")
  {
    dew = dewPoint(t, h);
    return String(dew);
  } else if (var == "MORELINES")
  {
    return moreLines();
  } else if (var == "MYDATE")
  {
    return (myDate());
  }
  return String();
}

Hi,
To find out what is not going on I felt on a simpler version using :
server.on(“/”, HTTP_GET, [](AsyncWebServerRequest * request) {
request->send_P(200, “text/html”, webPage, processor);
});
Right-clic and open in another tab.

Start your code here
/*
 * https://www.dfrobot.com/blog-1104.html
 * http://189.143.0.106/sensor
 * server.on("/sensor", HTTP_GET, [](AsyncWebServerRequest * request)
 * 
*/

#include "WiFi.h"
#include "ESPAsyncWebServer.h"


const char* host = "esp32";
const char *ssid = "23JANVIER-2012_Network_1";
const char *password = "cvq1-3bhy-afp6";
AsyncWebServer server(80);

const char *webPage =
  ""
  ""
  "Météo"
  ""
  "if (%CTEMP%>= 25){"
  "document.write(\"\");"
  "}"
  "else if (%CTEMP% = 5){"
  "document.write(\"\");"
  "}else if (%CTEMP% < 5){"
  "document.write(\"\");"
  "}"
  ""
  ""
  "%MYDATE%"
  ""
  "WIFISTRENGHT =  %WIFISTRENGHT%"
  "
Page en ligne pour "
  "%PAGETIME%"
  " minutes."
  " %CTEMP%"
  "°C"
  "Humidité du sol:  "
  "%VAL1%"
  "%,  "
  "%VAL2%"
  "%,  "
  "Température du sol:  "
  "%GROUND%"
  "°C"
  "Humidité: "
  "%HUMID_TEMP%"
  "%   Rosé: "
  "%DEW%"
  "°C  "
  "Ressenti: "
  "%HIC%"
  "°C"
  ""
  "%MORE_LINES%"
  ""
  "";

/*
 *   CTEMP MYDATE WIFISTRENGHT PAGETIME VAL1 VAL2 
 *   GROUND HUMID_TEMP DEW HIC MORE_LINES  
 */
  String processor(const String &var)
{
  float t = 0, h = 0;
  int val, vale, ground , wpt, hic, dew;
  float_t pw;
  Serial.println(var);
  if (var == "MYDATE")
  {
    return String("45 date");
  } else if (var == "WIFISTRENGHT")
  {
    pw = WiFi.RSSI();
    return isnan(pw) ? String("Error") : String(pw, 1);
  }else if (var == "PAGETIME")
    {
    wpt = 111;
    return String(wpt);//*
    }else if (var == "CTEMP")
  {
    t = 34;
    return String(t);
  } else if (var == "VAL1")
  {
    val = 11;
    return String(val);
  } else if (var == "VAL2")
  {
    vale = 40;
    return String(vale);
  } else if (var == "GROUND")
  {
    ground = 33; //String(analogRead(0), DEC); String(5.698, 3);
    return String(ground);
  } else if (var == "HUMID_TEMP")
  {
    h = 17;
    return String(h);
  } else if (var == "HIC")
  {
    hic = 55;
    return String(hic);
  } else if (var == "DEW")
  {
    dew = 44;
    return String(dew);
  } else if (var == "MORE_LINES")
  {
    String strr = "--------------
------------";
    return String(strr);
  }
  return String("-");
}

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi..");
  }
  Serial.println(WiFi.localIP());

  server.on("/", HTTP_GET, [](AsyncWebServerRequest * request) {
    request->send_P(200, "text/html", webPage, processor);
  });
  server.begin();
}

void loop(void) {  
//  server.handleClient();
//  delay(1);
  }
 

All placeholders now work.
Why does it not work with .
  server.on(“/webPage”, HTTP_GET, []() {
server.sendHeader(“Connection”, “close”);
server.send(200, “text/html”, webPage);
}); ?
Regards
 
JPD

// server.on("/webPage", HTTP_GET, []() {
// server.sendHeader("Connection", "close");
// server.send(200, "text/html", webPage);
// });

server.on("/webPage", HTTP_POST, [](AsyncWebServerRequest * request) {
request->send_P(200, "text/html", webPage, processor);
});
does not work

server.on(“/serverIndex”, HTTP_GET, []() {
server.sendHeader(“Connection”, “close”);
server.send(200, “text/html”, webPage);
});
gives this:

When you use this method:

server.on("/webPage", HTTP_POST, [](AsyncWebServerRequest * request) {
request->send_P(200, "text/html", webPage, processor);
});

The send() function accepts the processor as an argument. This way, it knows it needs to replace the placeholders with wathever we want on the processor().

The second snipet of code that you showed doesn’t do that, so it won’t call the procesor function and it won’t show the values.

Regards,
Sara

Hi,

It does not compile:

Arduino : 1.8.12 (Windows 10), Carte : “DOIT ESP32 DEVKIT V1, 80MHz, 921600, None”
OTA_Web_Updater.ino: In function ‘void setup()’:

OTA_Web_Updater:892:4: error: no matching function for call to ‘WebServer::on(const char [9], HTTPMethod, setup()::)’

WebServer.h:87:8: note: candidate: void WebServer::on(const String&, WebServer::THandlerFunction)

void on(const String &uri, THandlerFunction handler);

^

WebServer.h:87:8: note: candidate expects 2 arguments, 3 provided

WebServer.h:88:8: note: candidate: void WebServer::on(const String&, HTTPMethod, WebServer::THandlerFunction)

void on(const String &uri, HTTPMethod method, THandlerFunction fn);

^

WebServer.h:88:8: note: no known conversion for argument 3 from ‘setup()::’ to ‘WebServer::THandlerFunction {aka std::function}’

WebServer.h:89:8: note: candidate: void WebServer::on(const String&, HTTPMethod, WebServer::THandlerFunction, WebServer::THandlerFunction)

void on(const String &uri, HTTPMethod method, THandlerFunction fn, THandlerFunction ufn);

^

WebServer.h:89:8: note: candidate expects 4 arguments, 3 provided

server.on("/webPage", HTTP_POST, [](AsyncWebServerRequest * request) {
request->send_P(200, "text/html", webPage, processor);
});
/**************************/
server.on("/update", HTTP_POST, []() {
server.sendHeader("Connection", "close");
server.send(200, "text/plain", (Update.hasError()) ? "FAIL" : "OK");
ESP.restart();
}, []() {
HTTPUpload& upload = server.upload();
if (upload.status == UPLOAD_FILE_START) {
Serial.printf("Update: %s\n", upload.filename.c_str());
if (!Update.begin(UPDATE_SIZE_UNKNOWN)) { //start with max available size
Update.printError(Serial);
}
} else if (upload.status == UPLOAD_FILE_WRITE) {
/* flashing firmware to ESP*/
if (Update.write(upload.buf, upload.currentSize) != upload.currentSize) {
Update.printError(Serial);
}
} else if (upload.status == UPLOAD_FILE_END) {
if (Update.end(true)) { //true to set the size to the current progress
Serial.printf("Update Success: %u\nRebooting...\n", upload.totalSize);
} else {
Update.printError(Serial);
}
}
});

Full code here in the third answer:

full code

Regards,

JPD

Hi.
Can you try the following snipet?

server.on("/webPage", HTTP_GET, [](AsyncWebServerRequest * request) {
  request->send_P(200, "text/html", webPage, processor);
});

Regards,
Sara

Hi,

This is what I did in the previous answer. See just on top of the line:
/**************************/

I red that there was an incompatibility between the includes on another post …. It was not proven.

This function woks on it’s own file (example at the link (full code)).

https://www.dropbox.com/s/bsnzdzh3hsb2usa/page%20forum.png?dl=0

So I know at least the *webPage text has no error.

Regards,

JPD

Hi again.
What I suggested is different, is HTTP_GET and not HTTP_POST. Try it out like this:

server.on("/webPage", HTTP_GET, [](AsyncWebServerRequest * request) {
  request->send_P(200, "text/html", webPage, processor);
});

I don’t know what else may be causing the issue.
Regards, Sara

Hi,

It did not work either.

Hi.
I’m sorry but I don’t know what else can be wrong.
And at the moment, I can’t test the code on my own.
Try searching a bit more what might be causing the conflict, and return if you need further help.
Regards,
Sara

By the way I updated my code on github.
I created my own processor function, , token, and unconstchar function as replacement for  send_P   function thus there ias no more conflict in the headers.
 
Regards
 
JPD

That’s great.
I’ll mark this issue as resolved.
If you need further help, you just need to open a new question in our forum.
Regards,
Sara