Replaced MQTT lib with async, watchdog enabled, WifiClient

- MQTT now uses async-mqtt-client to prevent MQTT from blocking
- The esp32 watchdog is now enabled
- A lot of String variables changed to char
- HTTPClient changed to properly use WifiClient lib

Software/EmonESP/src/debug.h

@@ -30,6 +30,7 @@
 #define __DEBUG_H
 
 //#define ENABLE_DEBUG
+//#define DEBUG_PORT Serial
 
 #define TEXTIFY(A) #A
 #define ESCAPEQUOTE(A) TEXTIFY(A)

Software/EmonESP/src/emoncms.cpp

@@ -32,43 +32,31 @@
 #include "wifi.h"
 
 //EMONCMS SERVER strings
-const char *e_url = "/input/post.json?json=";
+const char* e_url = "/input/post.json?json=";
 boolean emoncms_connected = false;
 
 unsigned long packets_sent = 0;
 unsigned long packets_success = 0;
 unsigned long emoncms_connection_error_count = 0;
 
-void emoncms_publish(String data)
+static char url[MAX_DATA_LEN+100];
+
+void emoncms_publish(const char * data)
 {
   // We now create a URL for server data upload
-  String url = emoncms_path.c_str();
-  url += e_url;
-  url += "{";
-  // Copy across, data length
-  for (int i = 0; i < data.length(); ++i) {
-    url += data[i];
-  }
-  url += ",psent:";
-  url += packets_sent;
-  url += ",psuccess:";
-  url += packets_success;
-  url += ",freeram:";
-  url += String(ESP.getFreeHeap());
-  url += "}&node=";
-  url += emoncms_node;
-  url += "&apikey=";
-  url += emoncms_apikey;
+  sprintf(url, "%s%s{%s,psent:%lu,psuccess:%lu,freeram:%lu,rssi:%d}&node=%s&apikey=%s",
+    emoncms_path.c_str(), e_url, data, packets_sent, packets_success, ESP.getFreeHeap(),
+    WiFi.RSSI(), emoncms_node.c_str(), emoncms_apikey.c_str());
 
-  DBUGS.println(url); delay(10);
+  DBUGLN(url); delay(10);
   packets_sent++;
 
   // Send data to Emoncms server
   String result = "";
   if (emoncms_fingerprint != 0) {
     // HTTPS on port 443 if HTTPS fingerprint is present
     DBUGS.println("HTTPS Enabled"); delay(10);
-    result = get_https(emoncms_fingerprint.c_str(), emoncms_server.c_str(), url, 443);
+    result = get_http(emoncms_server.c_str(), url, 443, emoncms_fingerprint.c_str());
   } else {
     // Plain HTTP if other emoncms server e.g EmonPi
     DBUGS.println("Plain old HTTP"); delay(10);

Software/EmonESP/src/emoncms.h

@@ -44,6 +44,6 @@ extern unsigned long packets_success;
 //
 // data: a comma seperated list of name:value pairs to send
 // -------------------------------------------------------------------
-void emoncms_publish(String data);
+void emoncms_publish(const char * data);
 
 #endif // _EMONESP_EMONCMS_H

Software/EmonESP/src/emonesp.h

@@ -35,4 +35,7 @@
 
 #include "debug.h"
 
+#define ENABLE_WDT
+#define MAX_DATA_LEN 4096
+
 #endif // _EMONESP_H

Software/EmonESP/src/energy_meter.cpp

@@ -99,8 +99,6 @@ const int period = 1000; //time interval in ms to send data
   Otherwise a CT may be backwards */
 bool canBeNegative = true; 
 
-
-char result[200];
 char measurement[16];
 
 ATM90E32 eic{}; //initialize the IC class
@@ -157,6 +155,9 @@ void energy_meter_setup() {
 // -------------------------------------------------------------------
 void energy_meter_loop()
 {
+
+  char * result = input_string;
+
   /*get the current "time" (actually the number of milliseconds since the program started)*/
   currentMillis = millis();
 
@@ -456,11 +457,11 @@ void energy_meter_loop()
   dtostrf(eic.GetTotalApparentPower(), 2, 4, measurement);
   strcat(result, measurement);
 
-  strcat(result, ",PhaseA:");
+  strcat(result, ",CT1Angle:");
   dtostrf(eic.GetPhaseA(), 2, 2, measurement);
   strcat(result, measurement);
 
-  strcat(result, ",PhaseC:");
+  strcat(result, ",CT2Angle:");
   dtostrf(eic.GetPhaseC(), 2, 2, measurement);
   strcat(result, measurement);
 #endif
@@ -478,6 +479,4 @@ void energy_meter_loop()
 
   //DBUGS.println(result);
 
-  input_string = result;
-
 }

Software/EmonESP/src/http.cpp

@@ -28,39 +28,53 @@
 #include "emonesp.h"
 #include "http.h"
 
-WiFiClientSecure client;        // Create class for HTTPS TCP connections get_https()
-HTTPClient http;                // Create class for HTTP TCP connections get_http()
+#define HTTP_TIMEOUT 4
+
+WiFiClient client;                  // Create class for HTTP TCP connections get_http()
+WiFiClientSecure client_ssl;        // Create class for HTTPS TCP connections get_https()
+
+static char request[MAX_DATA_LEN+100];
 
 // -------------------------------------------------------------------
-// HTTPS SECURE GET Request
+// HTTP or HTTPS GET Request
 // url: N/A
 // -------------------------------------------------------------------
 
-String
-get_https(const char *fingerprint, const char *host, String url,
-          int httpsPort) {
+String get_http(const char * host, const char * url, int port, const char * fingerprint) {
+  WiFiClientSecure * http;
+
+  if (fingerprint) {
+    http = &client_ssl;
+  } else {
+    http = (WiFiClientSecure *) &client;
+  }
+
   // Use WiFiClient class to create TCP connections
-  if (!client.connect(host, httpsPort)) {
-    DBUGS.print(host + httpsPort);      //debug
+  if (!http->connect(host, port, HTTP_TIMEOUT*1000)) {
+    DBUGS.printf("%s:%d\n", host, port);      //debug
     return ("Connection error");
   }
+  http->setTimeout(HTTP_TIMEOUT);
 #ifndef ESP32
 #warning HTTPS verification not enabled
-  if (client.verify(fingerprint, host)) {
+  if (!fingerprint || http->verify(fingerprint, host)) {
 #endif
-    client.print(String("GET ") + url + " HTTP/1.1\r\n" + "Host: " + host +
-                 "\r\n" + "Connection: close\r\n\r\n");
+    sprintf(request, "GET %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n", url, host);
+    http->print(request);
     // Handle wait for reply and timeout
     unsigned long timeout = millis();
-    while (client.available() == 0) {
-      if (millis() - timeout > 5000) {
-        client.stop();
+    while (http->available() == 0) {
+      if (millis() - timeout > (HTTP_TIMEOUT*1000)) {
+        http->stop();
         return ("Client Timeout");
       }
+#ifdef ENABLE_WDT
+      feedLoopWDT();
+#endif
     }
     // Handle message receive
-    while (client.available()) {
-      String line = client.readStringUntil('\r');
+    while (http->available()) {
+      String line = http->readStringUntil('\r');
       DBUGS.println(line);      //debug
       if (line.startsWith("HTTP/1.1 200 OK")) {
         return ("ok");
@@ -73,22 +87,3 @@ get_https(const char *fingerprint, const char *host, String url,
 #endif
   return ("error " + String(host));
 }
-
-// -------------------------------------------------------------------
-// HTTP GET Request
-// url: N/A
-// -------------------------------------------------------------------
-String
-get_http(const char *host, String url) {
-  http.begin(String("http://") + host + String(url));
-  int httpCode = http.GET();
-  if ((httpCode > 0) && (httpCode == HTTP_CODE_OK)) {
-    String payload = http.getString();
-    DBUGS.println(payload);
-    http.end();
-    return (payload);
-  } else {
-    http.end();
-    return ("server error: " + String(httpCode));
-  }
-}                               // end http_get

Software/EmonESP/src/http.h

@@ -35,26 +35,13 @@
 
 #include <Arduino.h>
 #include <Print.h>
+#include <WiFiClient.h>         // http GET request
 #include <WiFiClientSecure.h>   // Secure https GET request
 
-#ifdef ESP32
-#include <HTTPClient.h>
-#elif defined(ESP8266)
-#include <ESP8266HTTPClient.h>
-#else
-#error Platform not supported
-#endif
-
-// -------------------------------------------------------------------
-// HTTPS SECURE GET Request
-// url: N/A
-// -------------------------------------------------------------------
-extern String get_https(const char* fingerprint, const char* host, String url, int httpsPort);
-
 // -------------------------------------------------------------------
-// HTTP GET Request
+// HTTP or HTTPS GET Request
 // url: N/A
 // -------------------------------------------------------------------
-extern String get_http(const char* host, String url);
+extern String get_http(const char * host, const char * url, int port=80, const char * fingerprint=NULL);
 
 #endif // _EMONESP_HTTP_H

Software/EmonESP/src/input.cpp

@@ -29,17 +29,17 @@
 #include "emonesp.h"
 #include "input.h"
 
-String input_string = "";
-String last_datastr = "";
+char input_string[MAX_DATA_LEN] = "";
+char last_datastr[MAX_DATA_LEN] = "";
 
-boolean input_get(String& data)
+boolean input_get(char * data)
 {
   boolean gotData = false;
 
   // If data from test API e.g `http://<IP-ADDRESS>/input?string=CT1:3935,CT2:325,T1:12.5,T2:16.9,T3:11.2,T4:34.7`
-  if (input_string.length() > 0) {
-    data = input_string;
-    input_string = "";
+  if (strlen(input_string) > 0) {
+    strcpy(data, input_string);
+    strcpy(input_string, "");
     gotData = true;
   }
 #ifdef USE_SERIAL_INPUT
@@ -54,11 +54,11 @@ boolean input_get(String& data)
   if (gotData)
   {
     // Get rid of any whitespace, newlines etc
-    data.trim();
+    //data.trim();
 
-    if (data.length() > 0) {
-      DBUGS.printf("Got '%s'\n", data.c_str());
-      last_datastr = data;
+    if (strlen(data) > 0) {
+//      DBUGS.printf("Got '%s'\n", data.c_str());
+      strcpy(last_datastr, data);
     } else {
       gotData = false;
     }

Software/EmonESP/src/input.h

@@ -35,15 +35,15 @@
 // Support for reading input
 // -------------------------------------------------------------------
 
-extern String last_datastr;
-extern String input_string;
+extern char last_datastr[MAX_DATA_LEN];
+extern char input_string[MAX_DATA_LEN];
 
 // -------------------------------------------------------------------
 // Read input sent via the web_server or serial.
 //
 // data: if true is returned data will be updated with the new line of
 //       input
 // -------------------------------------------------------------------
-extern boolean input_get(String& data);
+extern boolean input_get(char * data);
 
 #endif // _EMONESP_INPUT_H