initial example working

Author: wassfila

.gitignore

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+.pio
+.vscode
+keys

README.md

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-# aws_core_pio
-ESP32 sample to publish on AWS IoT Core Thing using certificates and key
+# AWS IoT Core PIO
+This is an Platform IO integration of the AWS IoT Core example.
+The example publishes on an AWS IoT Core Thing using certificates and key.
+
+## dependencies
+* ArduinoJson
+* knolleary/PubSubClient
+
+## example sources
+policy and example code from
+https://aws.amazon.com/blogs/compute/building-an-aws-iot-core-device-using-aws-serverless-and-an-esp32/
+
+used PubSubClient as per the following example as found in platformio registry
+https://how2electronics.com/connecting-esp32-to-amazon-aws-iot-core-using-mqtt/
+

platformio.ini

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+[env]
+platform = espressif32
+framework = arduino
+board = esp32-c3-devkitm-1
+lib_deps =
+    [email protected]
+    knolleary/PubSubClient@^2.8
+[env:esp32-c3-devkitm-1]
+monitor_speed = 115200

src/.gitignore

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+secrets.h

src/main.cpp

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+#include <Arduino.h>
+
+#include "secrets.h"
+#include <WiFiClientSecure.h>
+#include <PubSubClient.h>
+#include <ArduinoJson.h>
+#include "WiFi.h"
+
+// The MQTT topics that this device should publish/subscribe
+#define AWS_IOT_PUBLISH_TOPIC   "esp32/pub"
+#define AWS_IOT_SUBSCRIBE_TOPIC "esp32/sub"
+
+WiFiClientSecure net = WiFiClientSecure();
+PubSubClient client(net);
+
+void messageHandler(char* topic, byte* payload, unsigned int length)
+{
+  Serial.print("incoming: ");
+  Serial.println(topic);
+ 
+  StaticJsonDocument<200> doc;
+  deserializeJson(doc, payload);
+  const char* message = doc["message"];
+  Serial.println(message);
+}
+
+void connectAWS()
+{
+  WiFi.mode(WIFI_STA);
+  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
+
+  Serial.println("Connecting to Wi-Fi");
+
+  while (WiFi.status() != WL_CONNECTED){
+    delay(500);
+    Serial.print(".");
+  }
+
+  Serial.println("Connecting AWS");
+  // Configure WiFiClientSecure to use the AWS IoT device credentials
+  net.setCACert(AWS_CERT_CA);
+  net.setCertificate(AWS_CERT_CRT);
+  net.setPrivateKey(AWS_CERT_PRIVATE);
+
+  Serial.println("Connecting to Endpoint");
+  // Connect to the MQTT broker on the AWS endpoint we defined earlier
+  client.setServer(AWS_IOT_ENDPOINT, 8883);
+
+  // Create a message handler
+  client.setCallback(messageHandler);
+
+  Serial.print("Connecting to AWS IOT");
+
+  while (!client.connect(THINGNAME)) {
+    Serial.print(".");
+    delay(100);
+  }
+
+  if(!client.connected()){
+    Serial.println("AWS IoT Timeout!");
+    return;
+  }
+
+  Serial.print("Subscribing to the topic");
+  // Subscribe to a topic
+  client.subscribe(AWS_IOT_SUBSCRIBE_TOPIC);
+
+  Serial.println("AWS IoT Connected!");
+}
+
+void publishMessage()
+{
+  StaticJsonDocument<200> doc;
+  doc["time"] = millis();
+  doc["sensor_a0"] = analogRead(0);
+  char jsonBuffer[512];
+  serializeJson(doc, jsonBuffer); // print to client
+
+  client.publish(AWS_IOT_PUBLISH_TOPIC, jsonBuffer);
+  Serial.println("published");
+}
+
+void setup() {
+  Serial.begin(115200);
+  connectAWS();
+}
+
+void loop() {
+  publishMessage();
+  client.loop();
+  delay(3000);
+}

src/secrets.h.example

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+#include <pgmspace.h>
+
+#define SECRET
+#define THINGNAME ""
+
+const char WIFI_SSID[] = "";
+const char WIFI_PASSWORD[] = "";
+const char AWS_IOT_ENDPOINT[] = "";
+
+// Amazon Root CA 1
+static const char AWS_CERT_CA[] PROGMEM = R"EOF(
+-----BEGIN CERTIFICATE-----
+
+-----END CERTIFICATE-----
+)EOF";
+
+// Device Certificate
+static const char AWS_CERT_CRT[] PROGMEM = R"KEY(
+-----BEGIN CERTIFICATE-----
+
+-----END CERTIFICATE-----
+)KEY";
+
+// Device Private Key
+static const char AWS_CERT_PRIVATE[] PROGMEM = R"KEY(
+-----BEGIN RSA PRIVATE KEY-----
+
+-----END RSA PRIVATE KEY-----
+
+)KEY";