FirebaseArduino: simpler Arduino wrapper

.travis.yml

@@ -1,9 +1,15 @@
 language: c
 sudo: false
+addons:
+  apt:
+    sources:
+    - ubuntu-toolchain-r-test
+    packages:
+    - g++-4.8
 env:
-- ARDUINO_VERSION=1.6.8 ARDUINO_ESP8266_VERSION=2.1.0 ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino
-- ARDUINO_VERSION=1.6.8 ARDUINO_ESP8266_VERSION=2.2.0-rc1 ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino
-- ARDUINO_VERSION=nightly ARDUINO_ESP8266_VERSION=master ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino
+- ARDUINO_VERSION=1.6.8 ARDUINO_ESP8266_VERSION=2.1.0 GCC_VERSION=4.8 ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino CXX=g++-${GCC_VERSION}
+- ARDUINO_VERSION=1.6.8 ARDUINO_ESP8266_VERSION=2.2.0-rc1 GCC_VERSION=4.8 ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino CXX=g++-${GCC_VERSION}
+- ARDUINO_VERSION=nightly ARDUINO_ESP8266_VERSION=master GCC_VERSION=4.8 ARDUINO_ROOT=${HOME}/arduino-${ARDUINO_VERSION} ARDUINO_ESP8266_ROOT=${ARDUINO_ROOT}/hardware/esp8266com/esp8266 ARDUINO_HOME=${HOME}/Arduino CXX=g++-${GCC_VERSION}
 install:
 - ( cd ${HOME} && curl -O https://downloads.arduino.cc/arduino-${ARDUINO_VERSION}-linux64.tar.xz && tar xvf arduino-${ARDUINO_VERSION}-linux64.tar.xz )
 - git clone --branch ${ARDUINO_ESP8266_VERSION} https://github.com/esp8266/Arduino.git ${ARDUINO_ESP8266_ROOT}
@@ -13,3 +19,4 @@ before_script:
 - ( cd ${ARDUINO_HOME}/libraries && ln -s ${TRAVIS_BUILD_DIR} firebase-arduino && ln -s ${TRAVIS_BUILD_DIR}/src/third-party/arduino-json-5.2 ArduinoJson )
 script:
 - ${ARDUINO_ROOT}/arduino-builder -verbose  -hardware ${ARDUINO_ROOT}/hardware/ -tools ${ARDUINO_ESP8266_ROOT}/tools/ -tools ${ARDUINO_ROOT}/tools-builder/ -fqbn esp8266com:esp8266:nodemcuv2 -libraries ${ARDUINO_HOME}/libraries/ -prefs build.flash_ld=${ARDUINO_ESP8266_ROOT}/tools/sdk/ld/eagle.flash.4m.ld -prefs build.flash_freq=40 -prefs build.flash_size=4M examples/FirebasePush_ESP8266/FirebasePush_ESP8266.ino
+- cd test && make check

examples/FirebasePush_ESP8266/FirebasePush_ESP8266.ino

@@ -14,15 +14,11 @@
 // limitations under the License.
 //
 
-// FirebasePush_ESP8266 is a sample that push a new timestamp to firebase
-// on each reset.
+// FirebasePush_ESP8266 is a sample that push a new value to Firebase
+// every seconds.
 
 #include <ESP8266WiFi.h>
-
-#include <Firebase.h>
-
-// create firebase client.
-Firebase fbase("example.firebaseio.com", "secret_or_token");
+#include <FirebaseArduino.h>
 
 void setup() {
   Serial.begin(9600);
@@ -37,29 +33,21 @@ void setup() {
   Serial.println();
   Serial.print("connected: ");
   Serial.println(WiFi.localIP());
+
+  Firebase.begin("example.firebaseio.com", "auth_or_token");
+}
 
-   // add a new entry.
-  FirebasePush push = fbase.push("/logs", "{\".sv\": \"timestamp\"}");
-  if (push.error()) {
-      Serial.println("Firebase push failed");
-      Serial.println(push.error().message());  
-      return;
-  }
-
-  // print key.
-  Serial.println("Name: " + push.name());
+int n = 0;
 
-  // get all entries.
-  FirebaseGet get = fbase.get("/logs");
-  if (get.error()) {
-      Serial.println("Firebase get failed");
-      Serial.println(push.error().message());  
+void loop() {
+  // push a new value.
+  String name = Firebase.push("/logs", n++);
+  if (Firebase.failed()) {
+      Serial.print("push failed: ");
+      Serial.println(Firebase.error());  
       return;
   }
-  // Print written timestamp.
-  String data = get.json()[push.name()];
-  Serial.println("Timestamp:" + data);
-}
-
-void loop() {
+  Serial.print("pushed: ");
+  Serial.println(name);
+  delay(1000);
 }

src/FirebaseArduino.cpp

@@ -0,0 +1,86 @@
+//
+// 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.
+//
+
+#include "FirebaseArduino.h"
+
+void FirebaseArduino::begin(const char* host, const char* auth) {
+  http_.reset(FirebaseHttpClient::create());
+  http_->setReuseConnection(true);
+  host_ = host;
+  auth_ = auth;
+}
+
+String FirebaseArduino::FirebaseArduino::push(const String& path, const JsonVariant& value) {
+  String buf;
+  value.printTo(buf);
+  auto push = FirebasePush(host_, auth_, path, buf, http_.get());
+  error_ = push.error();
+  return push.name();
+}
+
+void FirebaseArduino::set(const String& path, const JsonVariant& value) {
+  String buf;
+  value.printTo(buf);
+  auto set = FirebaseSet(host_, auth_, path, buf, http_.get());
+  error_ = set.error();
+}
+
+FirebaseObject FirebaseArduino::get(const char* path) {
+  auto get = FirebaseGet(host_, auth_, path, http_.get());
+  error_ = get.error();
+  if (!error_) {
+    return FirebaseObject{""};
+  }
+  return FirebaseObject(get.response());
+}
+
+void FirebaseArduino::remove(const char* path) {
+  auto remove = FirebaseRemove(host_, auth_, path, http_.get());
+  error_ = remove.error();
+}
+
+void FirebaseArduino::stream(const char* path) {
+  auto stream = FirebaseStream(host_, auth_, path, http_.get());
+  error_ = stream.error();
+}
+
+bool FirebaseArduino::available() {
+  return http_->getStreamPtr()->available();
+}
+
+FirebaseObject FirebaseArduino::readEvent() {
+  auto client = http_->getStreamPtr();
+  String type = client->readStringUntil('\n').substring(7);;
+  String event = client->readStringUntil('\n').substring(6);
+  client->readStringUntil('\n'); // consume separator
+  FirebaseObject obj = FirebaseObject(event);
+  obj["type"] = type;
+  return obj;
+}
+
+bool FirebaseArduino::success() {
+  return error_.code() == 0;
+}
+
+bool FirebaseArduino::failed() {
+  return error_.code() != 0;
+}
+
+const String& FirebaseArduino::error() {
+  return error_.message();
+}
+
+FirebaseArduino Firebase;

src/FirebaseArduino.h

@@ -0,0 +1,49 @@
+//
+// 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 FIREBASE_ARDUINO_H
+#define FIREBASE_ARDUINO_H
+
+#include "Firebase.h"
+#include "FirebaseObject.h"
+
+#ifndef FIREBASE_JSONBUFFER_SIZE
+#define FIREBASE_JSONBUFFER_SIZE 200
+#endif // FIREBASE_JSONBUFFER_SIZE
+
+class FirebaseArduino {
+ public:
+  void begin(const char* host, const char* auth = "");
+  String push(const String& path, const JsonVariant& value);
+  void set(const String& path, const JsonVariant& value);
+  FirebaseObject get(const char* path);
+  void remove(const char* path);
+  void stream(const char* path);
+  bool available();
+  FirebaseObject readEvent();
+  bool success();
+  bool failed();
+  const String& error();
+ private:
+  String host_;
+  String auth_;
+  FirebaseError error_;
+  std::unique_ptr<FirebaseHttpClient> http_;
+};
+
+extern FirebaseArduino Firebase;
+
+#endif // FIREBASE_ARDUINO_H

src/FirebaseObject.cpp

@@ -0,0 +1,72 @@
+//
+// 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.
+//
+
+#include "FirebaseObject.h"
+
+namespace {
+template<typename T>
+T decodeJsonLiteral(const String& json) {
+  return JsonVariant{ArduinoJson::RawJson{json.c_str()}};
+}
+
+// ugly workaround to https://github.com/bblanchon/ArduinoJson/issues/265
+template<>
+String decodeJsonLiteral<String>(const String& json) {
+  StaticJsonBuffer<JSON_ARRAY_SIZE(1)> buf;
+  String array = "[" + json + "]";
+  return buf.parseArray(&array[0])[0];
+}
+}  // namespace
+
+FirebaseObject::FirebaseObject(const String& data) : data_{data} {
+  if (data_[0] == '{') {
+    json_ = &buffer_.parseObject(&data_[0]);
+  } else if (data_[0] == '"') {
+    data_ = decodeJsonLiteral<String>(data_);
+  }
+}
+
+FirebaseObject::operator bool() {
+  return decodeJsonLiteral<bool>(data_);
+}
+
+FirebaseObject::operator int() {
+    return decodeJsonLiteral<int>(data_);
+}
+
+FirebaseObject::operator float() {
+    return decodeJsonLiteral<float>(data_);
+}
+
+FirebaseObject::operator const String&() {
+    return data_;
+}
+
+FirebaseObject::operator const JsonObject&() {
+  return *json_;
+}
+
+JsonObjectSubscript<const char*> FirebaseObject::operator[](const char* key) {
+    return json_->operator[](key);
+}
+
+JsonObjectSubscript<const String&> FirebaseObject::operator[](const String& key) {
+  return json_->operator[](key);
+}
+
+JsonVariant FirebaseObject::operator[](JsonObjectKey key) const {
+  return json_->operator[](key);
+}

src/FirebaseObject.h

@@ -0,0 +1,41 @@
+//
+// Copyright 2015 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 FIREBASE_OBJECT_H
+#define FIREBASE_OBJECT_H
+
+#include "third-party/arduino-json-5.2/include/ArduinoJson.h"
+
+#define FIREBASE_JSONBUFFER_SIZE 200
+
+class FirebaseObject {
+ public:
+  FirebaseObject(const String& data);
+  operator bool();
+  operator int();
+  operator float();
+  operator const String&();
+  operator const JsonObject&();
+  JsonObjectSubscript<const char*> operator[](const char* key);
+  JsonObjectSubscript<const String&> operator[](const String& key);
+  JsonVariant operator[](JsonObjectKey key) const;
+ private:
+  String data_;
+  StaticJsonBuffer<FIREBASE_JSONBUFFER_SIZE> buffer_;
+  JsonObject* json_;
+};
+
+#endif // FIREBASE_OBJECT_H

test/FirebaseArduino_test.cpp

@@ -0,0 +1,43 @@
+//
+// 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.
+//
+
+#include "FirebaseObject.h"
+#include "gtest/gtest.h"
+
+TEST(FirebaseObjectTest, JsonLiteral) {
+  EXPECT_EQ(bool(FirebaseObject("true")), true);
+  EXPECT_EQ(bool(FirebaseObject("false")), false);
+  EXPECT_EQ(int(FirebaseObject("42")), 42);
+  EXPECT_EQ(float(FirebaseObject("43.0")), 43.0);
+  EXPECT_EQ(String(FirebaseObject("\"foo\"")), "foo");
+}
+
+TEST(FirebaseObjectTest, JsonObject) {
+  {
+    const JsonObject& obj = FirebaseObject("{\"foo\":\"bar\"}");
+    String foo = obj["foo"];
+    EXPECT_EQ(foo, "bar");
+  }
+  {
+    String foo = FirebaseObject("{\"foo\":\"bar\"}")["foo"];
+    EXPECT_EQ(foo, "bar");
+  }
+}
+
+int main(int argc, char **argv) {
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}