OK, ich hab ein wenig quer gelesen zum Thema Ajax und jquery, aber ich bin noch ein gutes Stück weg davon, selber funktionierenden Code in der Hinsicht zu schreiben. Ich machs mal konkret. Das hier ist die Index.html, ausgeliefert zusammen mit dem Javascript-Schnipsel vom ESP8266:
Code: Alles auswählen
<!doctype html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Gewächshaus</title>
<script src="gauge.min.js"></script>
</head>
<body style="background: #222">
<hr>
<canvas data-type="radial-gauge"
data-width="500"
data-height="500"
data-units="°C"
data-title="Gewächshaus"
data-min-value="-50"
data-max-value="50"
data-major-ticks="[-50,-40,-30,-20,-10,0,10,20,30,40,50]"
data-minor-ticks="2"
data-stroke-ticks="true"
data-highlights='[ {"from": -50, "to": 0, "color": "rgba(0,0, 255, .3)"},
{"from": 0, "to": 50, "color": "rgba(255, 0, 0, .3)"} ]'
data-ticks-angle="225"
data-start-angle="67.5"
data-color-major-ticks="#ddd"
data-color-minor-ticks="#ddd"
data-color-title="#eee"
data-color-units="#ccc"
data-color-numbers="#eee"
data-color-plate="#222"
data-border-shadow-width="0"
data-borders="true"
data-needle-type="arrow"
data-needle-width="2"
data-needle-circle-size="7"
data-needle-circle-outer="true"
data-needle-circle-inner="false"
data-animation-duration="1500"
data-animation-rule="linear"
data-color-border-outer="#333"
data-color-border-outer-end="#111"
data-color-border-middle="#222"
data-color-border-middle-end="#111"
data-color-border-inner="#111"
data-color-border-inner-end="#333"
data-color-needle-shadow-down="#333"
data-color-needle-circle-outer="#333"
data-color-needle-circle-outer-end="#111"
data-color-needle-circle-inner="#111"
data-color-needle-circle-inner-end="#222"
data-value-box-border-radius="0"
data-color-value-box-rect="#222"
data-color-value-box-rect-end="#333"
data-value='%TEMPERATURE%'
></canvas>
</body>
</html>
Die Zeile
data-value='%TEMPERATURE%' macht mit die Schnittstelle zu meinem Sketch, im wesentlichen ein Beispiel aus dem
ESPAsyncWebServer
Code: Alles auswählen
#include <ArduinoOTA.h>
#ifdef ESP32
#include <FS.h>
#include <SPIFFS.h>
#include <ESPmDNS.h>
#include <WiFi.h>
#include <AsyncTCP.h>
#elif defined(ESP8266)
#include <ESP8266WiFi.h>
#include <ESPAsyncTCP.h>
#include <ESP8266mDNS.h>
#endif
#include <ESPAsyncWebServer.h>
#include <SPIFFSEditor.h>
float Temp = 0;
unsigned long Zeit = 0;
// SKETCH BEGIN
AsyncWebServer server(80);
AsyncWebSocket ws("/ws");
AsyncEventSource events("/events");
void onWsEvent(AsyncWebSocket * server, AsyncWebSocketClient * client, AwsEventType type, void * arg, uint8_t *data, size_t len){
if(type == WS_EVT_CONNECT){
Serial.printf("ws[%s][%u] connect\n", server->url(), client->id());
client->printf("Hello Client %u :)", client->id());
client->ping();
} else if(type == WS_EVT_DISCONNECT){
Serial.printf("ws[%s][%u] disconnect\n", server->url(), client->id());
} else if(type == WS_EVT_ERROR){
Serial.printf("ws[%s][%u] error(%u): %s\n", server->url(), client->id(), *((uint16_t*)arg), (char*)data);
} else if(type == WS_EVT_PONG){
Serial.printf("ws[%s][%u] pong[%u]: %s\n", server->url(), client->id(), len, (len)?(char*)data:"");
} else if(type == WS_EVT_DATA){
AwsFrameInfo * info = (AwsFrameInfo*)arg;
String msg = "";
if(info->final && info->index == 0 && info->len == len){
//the whole message is in a single frame and we got all of it's data
Serial.printf("ws[%s][%u] %s-message[%llu]: ", server->url(), client->id(), (info->opcode == WS_TEXT)?"text":"binary", info->len);
if(info->opcode == WS_TEXT){
for(size_t i=0; i < info->len; i++) {
msg += (char) data[i];
}
} else {
char buff[3];
for(size_t i=0; i < info->len; i++) {
sprintf(buff, "%02x ", (uint8_t) data[i]);
msg += buff ;
}
}
Serial.printf("%s\n",msg.c_str());
if(info->opcode == WS_TEXT)
client->text("I got your text message");
else
client->binary("I got your binary message");
} else {
//message is comprised of multiple frames or the frame is split into multiple packets
if(info->index == 0){
if(info->num == 0)
Serial.printf("ws[%s][%u] %s-message start\n", server->url(), client->id(), (info->message_opcode == WS_TEXT)?"text":"binary");
Serial.printf("ws[%s][%u] frame[%u] start[%llu]\n", server->url(), client->id(), info->num, info->len);
}
Serial.printf("ws[%s][%u] frame[%u] %s[%llu - %llu]: ", server->url(), client->id(), info->num, (info->message_opcode == WS_TEXT)?"text":"binary", info->index, info->index + len);
if(info->opcode == WS_TEXT){
for(size_t i=0; i < len; i++) {
msg += (char) data[i];
}
} else {
char buff[3];
for(size_t i=0; i < len; i++) {
sprintf(buff, "%02x ", (uint8_t) data[i]);
msg += buff ;
}
}
Serial.printf("%s\n",msg.c_str());
if((info->index + len) == info->len){
Serial.printf("ws[%s][%u] frame[%u] end[%llu]\n", server->url(), client->id(), info->num, info->len);
if(info->final){
Serial.printf("ws[%s][%u] %s-message end\n", server->url(), client->id(), (info->message_opcode == WS_TEXT)?"text":"binary");
if(info->message_opcode == WS_TEXT)
client->text("I got your text message");
else
client->binary("I got your binary message");
}
}
}
}
}
const char* ssid = "xyz";
const char* password = "Jaja";
const char * hostName = "esp-async";
const char* http_username = "admin";
const char* http_password = "admin";
void setup(){
Serial.begin(115200);
Serial.setDebugOutput(true);
WiFi.mode(WIFI_AP_STA);
WiFi.softAP(hostName);
WiFi.begin(ssid, password);
if (WiFi.waitForConnectResult() != WL_CONNECTED) {
Serial.printf("STA: Failed!\n");
WiFi.disconnect(false);
delay(1000);
WiFi.begin(ssid, password);
}
//Send OTA events to the browser
ArduinoOTA.onStart([]() { events.send("Update Start", "ota"); });
ArduinoOTA.onEnd([]() { events.send("Update End", "ota"); });
ArduinoOTA.onProgress([](unsigned int progress, unsigned int total) {
char p[32];
sprintf(p, "Progress: %u%%\n", (progress/(total/100)));
events.send(p, "ota");
});
ArduinoOTA.onError([](ota_error_t error) {
if(error == OTA_AUTH_ERROR) events.send("Auth Failed", "ota");
else if(error == OTA_BEGIN_ERROR) events.send("Begin Failed", "ota");
else if(error == OTA_CONNECT_ERROR) events.send("Connect Failed", "ota");
else if(error == OTA_RECEIVE_ERROR) events.send("Recieve Failed", "ota");
else if(error == OTA_END_ERROR) events.send("End Failed", "ota");
});
ArduinoOTA.setHostname(hostName);
ArduinoOTA.begin();
MDNS.addService("http","tcp",80);
SPIFFS.begin();
ws.onEvent(onWsEvent);
server.addHandler(&ws);
events.onConnect([](AsyncEventSourceClient *client){
client->send("hello!",NULL,millis(),1000);
});
server.addHandler(&events);
#ifdef ESP32
server.addHandler(new SPIFFSEditor(SPIFFS, http_username,http_password));
#elif defined(ESP8266)
server.addHandler(new SPIFFSEditor(http_username,http_password));
#endif
/*
server.on("/heap", HTTP_GET, [](AsyncWebServerRequest *request){
request->send(200, "text/plain", String(ESP.getFreeHeap()));
});
*/
/*
server.serveStatic("/", SPIFFS, "/").setDefaultFile("index.html");
server.onNotFound([](AsyncWebServerRequest *request){
Serial.printf("NOT_FOUND: ");
if(request->method() == HTTP_GET)
Serial.printf("GET");
else if(request->method() == HTTP_POST)
Serial.printf("POST");
else if(request->method() == HTTP_DELETE)
Serial.printf("DELETE");
else if(request->method() == HTTP_PUT)
Serial.printf("PUT");
else if(request->method() == HTTP_PATCH)
Serial.printf("PATCH");
else if(request->method() == HTTP_HEAD)
Serial.printf("HEAD");
else if(request->method() == HTTP_OPTIONS)
Serial.printf("OPTIONS");
else
Serial.printf("UNKNOWN");
Serial.printf(" http://%s%s\n", request->host().c_str(), request->url().c_str());
if(request->contentLength()){
Serial.printf("_CONTENT_TYPE: %s\n", request->contentType().c_str());
Serial.printf("_CONTENT_LENGTH: %u\n", request->contentLength());
}
int headers = request->headers();
int i;
for(i=0;i<headers;i++){
AsyncWebHeader* h = request->getHeader(i);
Serial.printf("_HEADER[%s]: %s\n", h->name().c_str(), h->value().c_str());
}
int params = request->params();
for(i=0;i<params;i++){
AsyncWebParameter* p = request->getParam(i);
if(p->isFile()){
Serial.printf("_FILE[%s]: %s, size: %u\n", p->name().c_str(), p->value().c_str(), p->size());
} else if(p->isPost()){
Serial.printf("_POST[%s]: %s\n", p->name().c_str(), p->value().c_str());
} else {
Serial.printf("_GET[%s]: %s\n", p->name().c_str(), p->value().c_str());
}
}
request->send(404);
});
server.onFileUpload([](AsyncWebServerRequest *request, const String& filename, size_t index, uint8_t *data, size_t len, bool final){
if(!index)
Serial.printf("UploadStart: %s\n", filename.c_str());
Serial.printf("%s", (const char*)data);
if(final)
Serial.printf("UploadEnd: %s (%u)\n", filename.c_str(), index+len);
});
server.onRequestBody([](AsyncWebServerRequest *request, uint8_t *data, size_t len, size_t index, size_t total){
if(!index)
Serial.printf("BodyStart: %u\n", total);
Serial.printf("%s", (const char*)data);
if(index + len == total)
Serial.printf("BodyEnd: %u\n", total);
});
*/
server.on("/gauge.min.js", HTTP_GET, [](AsyncWebServerRequest* request) {
request->send(SPIFFS, "/gauge.min.js");
});
server.on("/", HTTP_GET, [](AsyncWebServerRequest* request) {
request->send(SPIFFS, "/index.html", String(), false, replaceVariable);
});
server.begin();
Zeit = millis ();
}
void loop(){
ArduinoOTA.handle();
ws.cleanupClients();
#define TIMEOUT 200
if ((Zeit + TIMEOUT) < millis ())
{
Zeit = millis ();
Temp += 1;
if (Temp > 50) Temp = -50;
}
}
String replaceVariable(const String& var) {
if (var == "TEMPERATURE") return String(Temp, 2);
return String(); }
Die letzten drei Zeilen übermitteln also einen Wert, der in die HTML-Datei eingebaut wird. Wenn ich das richtig verstanden habe, ist es mit Ajax möglch, nur diese Werte zur Laufzeit auszutauschen. Soweit so gut, aber mir fehlt da ein sinnvolles Beispiel, so das ich nicht bei Null anfangen muss, insbesondere bei JS, da kenn ich nix von....