esp32-geiger-counter/ingest.cpp

#include <WiFi.h>

#include "GeigerData.h"

#include "credentials.h"

const char *thingsPeakUrl = "api.thingspeak.com";

bool connect() {
	uint16_t retries = 3;
	while (WiFi.status() != WL_CONNECTED && (--retries) > 0) {
		Serial.print("Trying to connect to ");
		Serial.print(wifiSsid);
		Serial.print(" ... ");
		WiFi.begin(wifiSsid, wifiPassword);
		uint16_t waitRemaining = 8;
		while (WiFi.status() != WL_CONNECTED && (--waitRemaining) > 0) {
			delay(500);
		}
		if (WiFi.status() == WL_CONNECTED) {
			Serial.println("successful");
			return true;
		} else {
			Serial.print("failed status=");
			Serial.println(WiFi.status());
		}
	}

	return WiFi.status() == WL_CONNECTED;
}

void initIngest() {
	connect();
}

void deinitIngest() {
	if (WiFi.status() == WL_CONNECTED) {
		Serial.println("Disconnecting WiFi");
		WiFi.disconnect(true, true);
	}
}

void ingest(GeigerData &geigerData, uint16_t intervalSamples) {
	if (!connect())
		return;

	WiFiClient client;
	if (!client.connect(thingsPeakUrl, 80)) {
		Serial.print("Connecting to ");
		Serial.print(thingsPeakUrl);
		Serial.println(" failed");
	} else {

		const uint32_t pulses = geigerData.getPreviousPulses(1,
				intervalSamples);
		const uint32_t cpm = uint32_t(
				pulses
						/ ((float) intervalSamples * geigerData.sampleSeconds
								/ 60.) + 0.5);
		const float uSph = geigerData.toMicroSievertPerHour(pulses,
				intervalSamples);

		const String content = "api_key=" + String(thingspeakApiKey)
				+ "&field1=" + String(cpm) + "&field2=" + String(uSph, 3);

		Serial.print("Ingesting cpm=");
		Serial.print(cpm);
		Serial.print(" uSph=");
		Serial.print(uSph, 3);
		Serial.print(" ... ");

		client.print("POST /update HTTP/1.1\n");

		client.print("Host: ");
		client.print(thingsPeakUrl);
		client.print("\n");

		client.print("Connection: close\n");

		client.print("Content-Type: application/x-www-form-urlencoded\n");
		client.print("Content-Length: ");
		client.print(content.length());
		client.print("\n\n");

		client.print(content);

		uint16_t timeout = 40;
		while (client.available() == 0 && (--timeout) > 0) {
			delay(50);
		}
		if (client.available() == 0) {
			Serial.println("failed (no response)");
		}

		Serial.println("response:");
		while (client.available()) {
			char c = client.read();
			Serial.write(c);
		}
		Serial.println();

		client.stop();
	}
}