commit b5c3a495130d8f68e345b37d4d6fb555118d6ebc
Author: Dirk Jahnke <dirk.jahnke@mailbox.org>
Date:   Fri Dec 25 15:52:54 2020 +0100

    Initial commit

diff --git a/.gitignore b/.gitignore
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+.pio
+.vscode/.browse.c_cpp.db*
+.vscode/c_cpp_properties.json
+.vscode/launch.json
+.vscode/ipch
diff --git a/.vscode/extensions.json b/.vscode/extensions.json
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+++ b/.vscode/extensions.json
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+{
+    // See http://go.microsoft.com/fwlink/?LinkId=827846
+    // for the documentation about the extensions.json format
+    "recommendations": [
+        "platformio.platformio-ide"
+    ]
+}
diff --git a/README.md b/README.md
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+# DoorBell-MQTT-Gateway
+
+Based on
+
+- Arduino Uno
+- Ethernet interface
+
+Watchout for GPIO changes as triggers for
+
+- door bell input
+- post box observer (post entry)
+- post box observer (takeout posts)
+- ...
diff --git a/include/README b/include/README
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+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html
diff --git a/lib/README b/lib/README
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+++ b/lib/README
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+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into executable file.
+
+The source code of each library should be placed in a an own separate directory
+("lib/your_library_name/[here are source files]").
+
+For example, see a structure of the following two libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional, custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+and a contents of `src/main.c`:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+PlatformIO Library Dependency Finder will find automatically dependent
+libraries scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html
diff --git a/platformio.ini b/platformio.ini
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+++ b/platformio.ini
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+; PlatformIO Project Configuration File
+;
+;   Build options: build flags, source filter
+;   Upload options: custom upload port, speed and extra flags
+;   Library options: dependencies, extra library storages
+;   Advanced options: extra scripting
+;
+; Please visit documentation for the other options and examples
+; https://docs.platformio.org/page/projectconf.html
+
+[env:uno]
+platform = atmelavr
+board = uno
+framework = arduino
+lib_deps = 
+	bblanchon/ArduinoJson@^6.17.2
+	knolleary/PubSubClient@^2.8
+	paulstoffregen/Ethernet@0.0.0-alpha+sha.9f41e8231b
diff --git a/src/main.cpp b/src/main.cpp
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+++ b/src/main.cpp
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+#include <Arduino.h>
+#include <SPI.h>
+#include <Ethernet.h>
+#include <PubSubClient.h>
+#include <ArduinoJson.h>
+#include <string.h>
+
+// Update these with values suitable for your network.
+byte mac[]    = {  0xDE, 0xED, 0xBA, 0xFE, 0xFE, 0xEA };
+IPAddress ip(192, 168, 89, 205);
+IPAddress mqttServerIP(192, 168, 89, 95);
+const char *mqttUser = "default";
+const char *mqttPassword = "12345678";
+
+const char *doorBellTopic = "doorBell";
+const char *postboxFlapTopic = "postboxFlap";
+const char *postboxDoorTopic = "postboxDoor";
+const char *doorBellTriggerSoundTopic = "doorBellTrigger";
+const char *postboxLightTopic = "postboxLight";
+
+EthernetClient ethClient;
+EthernetServer server(80);
+PubSubClient mqttClient(ethClient);
+#define DOOR_BELL_BUTTON_PIN 7
+#define POSTBOX_FLAP_PIN 5
+#define POSTBOX_DOOR_PIN 3
+// Output pins
+#define LED_PIN 13
+#define DOOR_BELL_BUZZER_PIN 6
+#define POSTBOX_LIGHT_PIN 4
+
+struct {
+  const uint8_t pin;
+  const unsigned long quietAfterTriggerFor_ms;
+  unsigned long lastTrigger_ts;
+  bool isTriggered;
+  const char *topic;
+} myInputs[] = {
+  { DOOR_BELL_BUTTON_PIN, 500, 0 , false, doorBellTopic },
+  { POSTBOX_FLAP_PIN, 1000, 0, false, postboxFlapTopic },
+  { POSTBOX_DOOR_PIN, 1000, 0, false, postboxDoorTopic }
+};
+#define NUM_INPUTS (sizeof(myInputs) / sizeof(myInputs[0]))
+int ledState = LOW;
+
+struct {
+  const uint8_t pin;
+  const unsigned long triggerTime_ms;
+  bool isTriggered;
+  unsigned long lastTrigger_ts;
+  const char *listenTopic; // can be triggered by mqtt message as well
+} myOutputs[] = {
+  { DOOR_BELL_BUZZER_PIN, 500, false, 0, doorBellTriggerSoundTopic},
+  { POSTBOX_LIGHT_PIN, 30000, false, 0, postboxLightTopic}
+};
+#define NUM_OUTPUTS (sizeof(myOutputs) / sizeof(myOutputs[0]))
+
+
+void switchOutputOn(unsigned int outputNumber) {
+  Serial.print(F("Switch output on: "));
+  Serial.print(outputNumber);
+  Serial.print(F(" (pin "));
+  Serial.print(myOutputs[outputNumber].pin);
+  Serial.print(F(") topic "));
+  Serial.println(myOutputs[outputNumber].listenTopic);
+  digitalWrite(myOutputs[outputNumber].pin, LOW);
+  myOutputs[outputNumber].isTriggered = true;
+  myOutputs[outputNumber].lastTrigger_ts = millis();
+}
+
+void switchOutputOff(unsigned int outputNumber) {
+  Serial.print(F("Switch output off: "));
+  Serial.print(outputNumber);
+  Serial.print(F(" (pin "));
+  Serial.print(myOutputs[outputNumber].pin);
+  Serial.print(F(") topic "));
+  Serial.println(myOutputs[outputNumber].listenTopic);
+  digitalWrite(myOutputs[outputNumber].pin, HIGH);
+  myOutputs[outputNumber].isTriggered = false;
+}
+
+void checkOutputAutoOff() {
+  static bool headerDone = false;
+  for (unsigned int outputNumber=0; outputNumber<NUM_OUTPUTS; ++outputNumber) {
+
+    if (myOutputs[outputNumber].isTriggered) {
+      if (!headerDone) {
+        Serial.print(F("checkOutputAutoOff: ts=")); Serial.println(millis());
+        headerDone = true;
+      }
+      //Serial.print(outputNumber); Serial.print(": ");
+      //Serial.println(myOutputs[outputNumber].lastTrigger_ts + myOutputs[outputNumber].triggerTime_ms);
+      if ((myOutputs[outputNumber].lastTrigger_ts + myOutputs[outputNumber].triggerTime_ms) < millis()) {
+        Serial.println(F("Auto off output:"));
+        switchOutputOff(outputNumber);
+      }
+    }
+  }
+}
+
+void mqttReceiveMessage(char* topic, uint8_t* payload, unsigned int length) {
+  Serial.print(F("Message arrived ["));
+  Serial.print(topic);
+  Serial.print(F("] "));
+  Serial.print(length);
+  Serial.print(F(" bytes: "));
+  Serial.println((char *) payload);
+  for (unsigned int i=0;i<length;i++) {
+    Serial.print((char)payload[i]);
+  }
+  Serial.println();
+  bool handlerFound = false;
+  for (unsigned int i=0; i<NUM_OUTPUTS; ++i) {
+    if (strcmp(myOutputs[i].listenTopic, topic) == 0) {
+      handlerFound = true;
+      if (strncmp((char *) payload, "on", length < 2 ? length : 2) == 0) {
+        switchOutputOn(i);
+      } else if (strncmp((char *) payload, "off", length < 3 ? length : 3) == 0) {
+        switchOutputOff(i);
+      } else {
+        Serial.print(F("Unknown MQTT message payload received, topic: "));
+        Serial.print(topic);
+        Serial.print(F(", payload: "));
+        Serial.println((char *) payload);
+      }
+    }
+  }
+  if (!handlerFound) {
+    Serial.print(F("Unknown MQTT message received, topic: "));
+    Serial.print(topic);
+    Serial.print(F(", payload: "));
+    Serial.println((char *) payload);
+  }
+}
+
+void reconnect() {
+  // Loop until we're reconnected
+  while (!mqttClient.connected()) {
+    Serial.print(F("Attempting MQTT connection..."));
+    // Attempt to connect
+    if (mqttClient.connect("doorBellGateway", mqttUser, mqttPassword)) {
+      Serial.println(F("connected"));
+      // Once connected, publish an announcement...
+      // mqttClient.publish("hello","hello world");
+      // ... and resubscribe
+      Serial.println(F("MQTT subscribe doorbell"));
+      if (!mqttClient.subscribe("doorbell")) {
+        Serial.println(F("ERROR: Failed to subscribe"));
+      }
+      for (unsigned int i=0; i<NUM_OUTPUTS; ++i) {
+        Serial.print(F("MQTT subscribe ")); Serial.println(myOutputs[i].listenTopic);
+        if (!mqttClient.subscribe(myOutputs[i].listenTopic)) {
+          Serial.println(F("ERROR: Failed to subscribe"));
+        }
+      }
+
+    } else {
+      Serial.print(F("failed, rc="));
+      Serial.print(mqttClient.state());
+      Serial.println(F(" try again in 5 seconds"));
+      // Wait 5 seconds before retrying
+      delay(5000);
+    }
+  }
+}
+
+void sendMqttMessage(const char *topic, const char *message) {
+  reconnect();
+  mqttClient.publish(topic, message);
+}
+
+void setup()
+{
+  // Initialize serial port
+  Serial.begin(9600);
+  while (!Serial) continue;
+  Serial.println(F("Arduino Door Bell MQTT Gateway started."));
+
+  mqttClient.setServer(mqttServerIP, 1883);
+  mqttClient.setCallback(mqttReceiveMessage);
+
+  // Initialize Ethernet libary
+  if (!Ethernet.begin(mac)) {
+    Serial.println(F("Failed to initialize Ethernet library"));
+    return;
+  }
+
+  // Start to listen
+  server.begin();
+  Serial.println(F("Server is ready."));
+  Serial.print(F("Please connect to http://"));
+  Serial.println(Ethernet.localIP());
+
+  // setup the input and output pins
+  for (unsigned int i = 0; i < NUM_INPUTS; i++) {
+    pinMode(myInputs[i].pin, INPUT_PULLUP);
+  }
+
+  // Setup the LED :
+  for (unsigned int i=0; i < NUM_OUTPUTS; ++i) {
+    pinMode(myOutputs[i].pin, OUTPUT);
+    switchOutputOff(i);
+  }
+  pinMode(LED_PIN, OUTPUT);
+  digitalWrite(LED_PIN, ledState);
+}
+
+
+void checkInputSignals() {
+  bool needToToggleLed = false;
+
+
+  for (unsigned int i = 0; i < NUM_INPUTS; i++)  {
+    if (millis()-myInputs[i].lastTrigger_ts > myInputs[i].quietAfterTriggerFor_ms) {
+      if (!digitalRead(myInputs[i].pin)) {
+        // input is triggered, compare with existing state
+        if (myInputs[i].isTriggered) {
+          // was triggered as well, could send a retrigger now
+          Serial.print(F("Re-Trigger pin ")); Serial.println(myInputs[i].pin);
+          sendMqttMessage(myInputs[i].topic, "re-trigger");
+          needToToggleLed = true;
+        } else {
+          // handle trigger now
+          myInputs[i].isTriggered = true;
+          // send Trigger
+          Serial.print(F("Trigger pin ")); Serial.println(myInputs[i].pin);
+          sendMqttMessage(myInputs[i].topic, "trigger");
+          needToToggleLed = true;
+        }
+        myInputs[i].lastTrigger_ts = millis();
+      } else {
+        // no trigger seen, if it was before, send a "released" message
+        if (myInputs[i].isTriggered) {
+          myInputs[i].isTriggered = false;
+          myInputs[i].lastTrigger_ts = millis();
+          Serial.print(F("Released pin ")); Serial.println(myInputs[i].pin);
+          sendMqttMessage(myInputs[i].topic, "release");
+          needToToggleLed = true;
+        }
+      }
+    }
+  }
+
+  // if a LED toggle has been flagged :
+  if ( needToToggleLed ) {
+    // Toggle LED state :
+    ledState = !ledState;
+    digitalWrite(LED_PIN, ledState);
+  }
+
+}
+
+void checkWebRequest() {
+  // Wait for an incomming connection
+  EthernetClient client = server.available();
+
+  // Do we have a client?
+  if (!client) return;
+
+  Serial.println(F("New client on web ingress"));
+
+  // Read the request (we ignore the content in this example)
+  while (client.available()) client.read();
+
+  // Allocate a temporary JsonDocument
+  // Use arduinojson.org/v6/assistant to compute the capacity.
+  StaticJsonDocument<500> doc;
+  
+  for (unsigned int pin = 0; pin < NUM_INPUTS; pin++) {
+    doc[myInputs[pin].topic] = myInputs[pin].isTriggered ? "triggered" : "released";
+  }
+
+  // Create the "digital" array
+  JsonArray digitalValues = doc.createNestedArray("digitalPin");
+  for (unsigned int pin = 0; pin < 14; pin++) {
+    // Read the digital input
+    int value = digitalRead(pin);
+
+    // Add the value at the end of the array
+    digitalValues.add(value);
+  }
+
+  Serial.print(F("Sending: "));
+  serializeJson(doc, Serial);
+  Serial.println();
+
+  // Write response headers
+  client.println(F("HTTP/1.0 200 OK"));
+  client.println(F("Content-Type: application/json"));
+  client.println(F("Connection: close"));
+  client.print(F("Content-Length: "));
+  // client.println(measureJsonPretty(doc));
+  client.println(measureJson(doc));
+  client.println();
+
+  // Write JSON document
+  //serializeJsonPretty(doc, client);
+  serializeJson(doc, client);
+  
+  // Disconnect
+  client.stop();
+}
+
+void loop() {
+  // Client
+  if (!mqttClient.connected()) {
+    reconnect();
+  }
+  mqttClient.loop();
+
+  checkInputSignals();
+
+  checkWebRequest();
+
+  checkOutputAutoOff();
+
+}
+
diff --git a/test/README b/test/README
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+
+This directory is intended for PlatformIO Unit Testing and project tests.
+
+Unit Testing is a software testing method by which individual units of
+source code, sets of one or more MCU program modules together with associated
+control data, usage procedures, and operating procedures, are tested to
+determine whether they are fit for use. Unit testing finds problems early
+in the development cycle.
+
+More information about PlatformIO Unit Testing:
+- https://docs.platformio.org/page/plus/unit-testing.html