Initial version of transcriber, works but can't write and read :(

Author: ed7coyne

src/FirebaseObject.cpp

@@ -25,7 +25,7 @@ FirebaseObject::FirebaseObject(const char* data) : data_{data} {
   // See: https://github.com/bblanchon/ArduinoJson/issues/279
 }
 
-bool FirebaseObject::getBool(const String& path) {
+bool FirebaseObject::getBool(const String& path) const {
   JsonVariant variant = getJsonVariant(path);
   if (!variant.is<bool>()) {
     error_ = "failed to convert to bool";
@@ -34,7 +34,7 @@ bool FirebaseObject::getBool(const String& path) {
   return static_cast<bool>(variant);
 }
 
-int FirebaseObject::getInt(const String& path) {
+int FirebaseObject::getInt(const String& path) const {
   JsonVariant variant = getJsonVariant(path);
   if (!variant.is<int>() && !variant.is<float>()) {
     error_ = "failed to convert to number";
@@ -43,7 +43,7 @@ int FirebaseObject::getInt(const String& path) {
   return static_cast<int>(variant);
 }
 
-float FirebaseObject::getFloat(const String& path) {
+float FirebaseObject::getFloat(const String& path) const {
   JsonVariant variant = getJsonVariant(path);
   if (!variant.is<float>() && !variant.is<int>()) {
     error_ = "failed to convert to number";
@@ -52,7 +52,7 @@ float FirebaseObject::getFloat(const String& path) {
   return static_cast<float>(variant);
 }
 
-String FirebaseObject::getString(const String& path) {
+String FirebaseObject::getString(const String& path) const {
   JsonVariant variant = getJsonVariant(path);
   if (!variant.is<const char *>()) {
     error_ = "failed to convert to string";
@@ -61,7 +61,7 @@ String FirebaseObject::getString(const String& path) {
   return static_cast<const char*>(variant);
 }
 
-JsonVariant FirebaseObject::getJsonVariant(const String& path) {
+JsonVariant FirebaseObject::getJsonVariant(const String& path) const {
   String key(path);
   char* start = &key[0];
   char* end = start + key.length();

src/FirebaseObject.h

@@ -40,35 +40,35 @@ class FirebaseObject {
    * \param optional path in the JSON object.
    * \return result as a bool.
    */
-  bool getBool(const String& path = "");
+  bool getBool(const String& path = "") const;
 
   /**
    * Return the value as an int.
    * \param optional path in the JSON object.
    * \return result as an integer.
    */
-  int getInt(const String& path = "");
+  int getInt(const String& path = "") const;
 
   /**
    * Return the value as a float.
    * \param optional path in the JSON object.
    * \return result as a float.
    */
-  float getFloat(const String& path = "");
+  float getFloat(const String& path = "") const;
 
   /**
    * Return the value as a String.
    * \param optional path in the JSON object.
    * \return result as a String.
    */
-  String getString(const String& path = "");
+  String getString(const String& path = "") const;
 
   /**
    * Return the value as a JsonVariant.
    * \param optional path in the JSON object.
    * \return result as a JsonVariant.
    */
-  JsonVariant getJsonVariant(const String& path = "");
+  JsonVariant getJsonVariant(const String& path = "") const;
 
 
   /**
@@ -93,7 +93,7 @@ class FirebaseObject {
   String data_;
   StaticJsonBuffer<FIREBASE_JSONBUFFER_SIZE> buffer_;
   JsonVariant json_;
-  String error_;
+  mutable String error_;
 };
 
 #endif // FIREBASE_OBJECT_H

src/Transcriber.h

@@ -0,0 +1 @@
+#include "thing/Transcriber.h"

src/thing/Config.h

@@ -0,0 +1,17 @@
+namespace thing {
+
+struct Config {
+  std::string host;
+  std::string auth;
+  std::string path;
+
+  std::string wifi_ssid;
+  std::string wifi_key;
+
+  int pin_digital_out;
+  int pin_digital_in;
+  int pin_analog_out;
+  int pin_analog_in;
+};
+
+}

src/thing/Transcriber.cpp

@@ -0,0 +1,91 @@
+
+#include "thing/Transcriber.h"
+
+namespace thing {
+namespace {
+  const char* kSubPathDigitalOut = "/digital_out";
+  const char* kSubPathDigitalIn = "/digital_in";
+  const char* kSubPathAnalogOut = "/analog_out";
+  const char* kSubPathAnalogIn = "/analog_in";
+}  // namespace
+
+
+Transcriber::Transcriber(const Config& config) {
+  Init(config);
+}
+
+void Transcriber::UpdateConfig(const Config& config) {
+  Init(config);
+}
+
+void Transcriber::Init(const Config& config) {
+  pin_digital_out_ = config.pin_digital_out;
+  pin_digital_in_ = config.pin_digital_in;
+  pin_analog_out_ = config.pin_analog_out;
+  pin_analog_in_ = config.pin_analog_in;
+
+  fbase_.reset(new Firebase(config.host, config.auth));
+  stream_ = fbase_->streamPtr(config.path);
+}
+
+void Transcriber::Loop() {
+  // Read incoming data
+  if (stream_->available()) {
+    std::string event_str;
+    if (stream_->read(event_str) == FirebaseStream::PUT) {
+      FirebaseObject update(event_str.c_str());
+      if (update.success()) {
+        if (update.getString("path") == "/") {
+          ProcessInitialUpdate(update);
+        } else {
+          ProcessIncrementalUpdate(update);
+        }
+      }
+    }
+  }
+
+  // Send values to cloud
+  int digital_in = digitalRead(pin_digital_in_);
+  if (digital_in != digital_in_) {
+Serial.println(String(digital_in).c_str());
+    FirebaseSet set = fbase_->set(kSubPathDigitalIn, String(digital_in).c_str());
+    digital_in_ = digital_in;
+  }
+
+  float analog_in = analogRead(pin_analog_in_);
+  if (analog_in != analog_in_) {
+Serial.println(String(analog_in).c_str());
+    FirebaseSet set = fbase_->set(kSubPathAnalogIn, String(analog_in).c_str());
+    analog_in_ = analog_in;
+  }
+}
+
+void Transcriber::ProcessInitialUpdate(const FirebaseObject& update) {
+  int digital_out = update.getInt((std::string("data") + kSubPathDigitalOut).c_str());
+  if (!update.failed()) {
+    digitalWrite(pin_digital_out_, digital_out);
+  }
+
+  float analog_out = update.getFloat((std::string("data") + kSubPathAnalogOut).c_str());
+  if (!update.failed()) {
+    analogWrite(pin_analog_out_, analog_out);
+  }
+}
+
+void Transcriber::ProcessIncrementalUpdate(const FirebaseObject& update) {
+  if (update.getString("path").equals(kSubPathDigitalOut)) {
+    int digital_out = update.getInt("data");
+    if (!update.failed()) {
+      digitalWrite(pin_digital_out_, update.getInt("data"));
+    }
+  }
+
+  if (update.getString("path").equals(kSubPathAnalogOut)) {
+    float analog_out = update.getFloat("data");
+    if (!update.failed()) {
+      analogWrite(pin_analog_out_, analog_out);
+    }
+  }
+}
+
+}  // thing

src/thing/Transcriber.h

@@ -0,0 +1,58 @@
+//
+// Copyright 2016 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+#ifndef transcriber_h
+#define transcriber_h
+
+#include <Arduino.h>
+#include <memory>
+#include <utility>
+#include <vector>
+#include "Firebase.h"
+#include "FirebaseObject.h"
+#include "third-party/arduino-json-5.3/include/ArduinoJson.h"
+#include "thing/Config.h"
+
+namespace thing {
+
+class Transcriber {
+ public:
+  Transcriber(const Config& config);
+  void UpdateConfig(const Config& config);
+  void Loop();
+
+ private:
+  void Init(const Config& config);
+
+  void ProcessInitialUpdate(const FirebaseObject& update);
+  void ProcessIncrementalUpdate(const FirebaseObject& update);
+
+  std::unique_ptr<Firebase> fbase_;
+  std::unique_ptr<FirebaseStream> stream_;
+
+  int digital_in_ = 0;
+  float analog_in_ = 0.0f;
+
+  int pin_digital_out_;
+  int pin_digital_in_;
+  int pin_analog_out_;
+  int pin_analog_in_;
+};
+
+};  // thing
+
+
+#endif  // transcriber_h