diff --git a/doc/esp8266wifi/server-examples.rst b/doc/esp8266wifi/server-examples.rst
index 5a684d5cc7..cdd18fe81a 100644
--- a/doc/esp8266wifi/server-examples.rst
+++ b/doc/esp8266wifi/server-examples.rst
@@ -39,17 +39,19 @@ Then let's write a short function ``prepareHtmlPage()``, that will return a ``St
String prepareHtmlPage()
{
- String htmlPage =
- String("HTTP/1.1 200 OK\r\n") +
- "Content-Type: text/html\r\n" +
- "Connection: close\r\n" + // the connection will be closed after completion of the response
- "Refresh: 5\r\n" + // refresh the page automatically every 5 sec
- "\r\n" +
- "<!DOCTYPE HTML>" +
- "<html>" +
- "Analog input: " + String(analogRead(A0)) +
- "</html>" +
- "\r\n";
+ String htmlPage;
+ htmlPage.reserve(1024); // prevent ram fragmentation
+ htmlPage = F("HTTP/1.1 200 OK\r\n"
+ "Content-Type: text/html\r\n"
+ "Connection: close\r\n" // the connection will be closed after completion of the response
+ "Refresh: 5\r\n" // refresh the page automatically every 5 sec
+ "\r\n"
+ "<!DOCTYPE HTML>"
+ "<html>"
+ "Analog input: ");
+ htmlPage += analogRead(A0);
+ htmlPage += F("</html>"
+ "\r\n");
return htmlPage;
}
@@ -79,7 +81,7 @@ The content contains two basic `HTML <https://www.w3schools.com/html/>`__ tags,
.. code:: cpp
- String(analogRead(A0))
+ analogRead(A0)
The Page is Served
~~~~~~~~~~~~~~~~~~
@@ -90,7 +92,7 @@ Serving of this web page will be done in the ``loop()`` where server is waiting
void loop()
{
- WiFiClient client = server.available();
+ WiFiClient client = server.available();
if (client)
{
// we have a new client sending some request
@@ -126,6 +128,18 @@ The whole process is concluded by stopping the connection with client:
client.stop();
+But before that, we must not interrupt client's request:
+
+.. code:: cpp
+
+ while (client.available()) {
+ // but first, let client finish its request
+ // that's diplomatic compliance to protocols
+ // (and otherwise some clients may complain, like curl)
+ // (that is an example, prefer using a proper webserver library)
+ client.read();
+ }
+
Put it Together
~~~~~~~~~~~~~~~
@@ -163,24 +177,26 @@ Complete sketch is presented below.
// prepare a web page to be send to a client (web browser)
String prepareHtmlPage()
{
- String htmlPage =
- String("HTTP/1.1 200 OK\r\n") +
- "Content-Type: text/html\r\n" +
- "Connection: close\r\n" + // the connection will be closed after completion of the response
- "Refresh: 5\r\n" + // refresh the page automatically every 5 sec
- "\r\n" +
- "<!DOCTYPE HTML>" +
- "<html>" +
- "Analog input: " + String(analogRead(A0)) +
- "</html>" +
- "\r\n";
+ String htmlPage;
+ htmlPage.reserve(1024); // prevent ram fragmentation
+ htmlPage = F("HTTP/1.1 200 OK\r\n"
+ "Content-Type: text/html\r\n"
+ "Connection: close\r\n" // the connection will be closed after completion of the response
+ "Refresh: 5\r\n" // refresh the page automatically every 5 sec
+ "\r\n"
+ "<!DOCTYPE HTML>"
+ "<html>"
+ "Analog input: ");
+ htmlPage += analogRead(A0);
+ htmlPage += F("</html>"
+ "\r\n");
return htmlPage;
}
void loop()
{
- WiFiClient client = server.available();
+ WiFiClient client = server.available();
// wait for a client (web browser) to connect
if (client)
{
@@ -200,7 +216,14 @@ Complete sketch is presented below.
}
}
}
- delay(1); // give the web browser time to receive the data
+
+ while (client.available()) {
+ // but first, let client finish its request
+ // that's diplomatic compliance to protocols
+ // (and otherwise some clients may complain, like curl)
+ // (that is an example, prefer using a proper webserver library)
+ client.read();
+ }
// close the connection:
client.stop();