libraries/firebase: simpler api

- method return raw http requests instead of sending them
- removed value() method: need helper for reading response.

Author: proppy

libraries/Firebase/Firebase.cpp

@@ -13,9 +13,12 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 //
-
 #include "Firebase.h"
-#include "Client.h"
+
+const char* firebaseFingerprint = "C1 56 CD D8 49 A3 7D D2 1D 49 60 7E 0D 59 A7 7C C1 0E 58 D2";
+const uint16_t firebasePort = 443;
+
+FirebaseRoot Firebase;
 
 FirebaseRef::FirebaseRef(FirebaseRoot& root, const String& path) : _root(root), _path(path) {
 }
@@ -24,16 +27,12 @@ FirebaseRef& FirebaseRef::root()  {
   return _root;
 }
 
-String FirebaseRef::value() {
-  return _root.makeRequest("GET", _path, "");
-}
-
-String FirebaseRef::set(const String& key, const String& value) {
-  return _root.makeRequest("PUSH", _path + "/" + key, value);
+String FirebaseRef::set(const String& value) {
+  return _root.buildRequest("PUT", _path, value);
 }
 
 String FirebaseRef::push(const String& value) {
-  return _root.makeRequest("POST", _path, value);
+  return _root.buildRequest("POST", _path, value);
 }
 
 FirebaseRef FirebaseRef::child(const String& key) {
@@ -43,32 +42,21 @@ FirebaseRef FirebaseRef::child(const String& key) {
 FirebaseRoot::FirebaseRoot() : FirebaseRef(*this, "") {
 }
 
-void FirebaseRoot::begin(Client& client, const String& host) {
-  _client = &client;
+void FirebaseRoot::begin(const String& host) {
   _host = host;
 }
 
 void FirebaseRoot::auth(const String& token) {
   _token = token;
 }
 
-void FirebaseRoot::setError(const String& err) {
-  _err = err;
-}
-
-const String& FirebaseRoot::error() {
-  return _err;
+FirebaseRef FirebaseRoot::child(const String& key) {
+  return FirebaseRef(*this, key);
 }
 
-String FirebaseRoot::makeRequest(const String& method, const String& path, const String& data) {
-  _err = "";
-  
-  if (!_client->connect(_host.c_str(), 443)) {
-    setError("failed to connect");
-    return "";
-  }    
+String FirebaseRoot::buildRequest(const String& method, const String& path, const String& data) {
   String req;
-  req += method + " " + path + ".json";
+  req += method + " /" + path + ".json";
   if (_token.length() > 0) {
     req += "?auth=" + _token;
   }
@@ -82,12 +70,17 @@ String FirebaseRoot::makeRequest(const String& method, const String& path, const
     req += "\r\n\r\n";
     req += data;
   }
-  _client->print(req);
-  String resp;
-  while(_client->available() > 0) {
-    resp += _client->readStringUntil('\n');
-  }
-  return resp;
+  return req;
 }
 
-FirebaseRoot Firebase;
+const char* FirebaseRoot::host() const {
+  return _host.c_str();
+}
+
+uint16_t FirebaseRoot::port() const {
+  return firebasePort;
+}
+
+const char* FirebaseRoot::fingerprint() const {
+  return firebaseFingerprint;
+}

libraries/Firebase/Firebase.h

@@ -14,41 +14,50 @@
 // limitations under the License.
 //
 
+// Firebase is an helper library for build Firebase request.
 #ifndef firebase_h
 #define firebase_h
 
-#include "WString.h"
+#include "Arduino.h"
 
 class Client;
 class FirebaseRoot;
 
+// FirebaseRef is a reference in the firebase hierarchy.
+//
+// Methods `set()` and `push()` returns the HTTP request as a raw
+// `String`, the requests then need be sent using an Arduino Wifi,
+// Ethernet or GSM `Client`.
 class FirebaseRef {
  public:
   FirebaseRef(FirebaseRoot& root, const String& path);
   FirebaseRef& root();
-  String value();
-  String set(const String& key, const String& value);
+  String set(const String& value);
   String push(const String& value);
   FirebaseRef child(const String& key);
  private:
   FirebaseRoot& _root;
   String _path;  
 };
 
+// FirebaseRoot is a root of firebase hierarchy.
+//
+// A global `Firebase` instance is available for convenience, and need
+// to be initialized with the `begin()` and `auth()` methods.
 class FirebaseRoot : public FirebaseRef {
   friend FirebaseRef;
  public:
   FirebaseRoot();
-  void begin(Client& client, const String& host);
+  void begin(const String& host);
   void auth(const String& token);
-  void setError(const String& err);
-  const String& error();
+  const char* host() const;
+  uint16_t port() const;
+  const char* fingerprint() const;
+  FirebaseRef child(const String& key);  
  private:
-  String makeRequest(const String& method, const String& path, const String& data);
-  Client* _client;
+  String buildRequest(const String& method, const String& path, const String& data);
   String _host;
   String _token;
-  String _err;  
 };
 
 extern FirebaseRoot Firebase;

libraries/Firebase/examples/FirebasePush_ESP8266/FirebasePush_ESP8266.ino

@@ -1,45 +1,48 @@
-//
-// 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.
-//
+// FirebasePush_ESP8266 is a sample that write a timestamp to a firebase
+// everytime it is powered on.
 
 #include <ESP8266WiFi.h>
 #include <WiFiClientSecure.h>
 
 #include <Firebase.h>
 
-WiFiClientSecure wifiClient;
-
-int pushButtonPin = 1;
-int previousState = 1;
+#define WIFI_SSID "..."
+#define WIFI_PASSWORD "..."
+#define FIREBASE_HOST "..."
+#define FIREBASE_TOKEN "..."
 
 void setup() {
-    pinMode(pushButtonPin, INPUT);
-    digitalWrite(pushButtonPin, HIGH);
- 
-    Serial.begin(9600);
-
-    WiFi.begin("my-ssid", "my-password");
-    Firebase.begin(wifiClient, "my-firebase.firebaseio.com");
-    Firebase.auth("my-firebase-token-or-secrent");
+  Serial.begin(9600);
+  
+  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
+  while (WiFi.status() != WL_CONNECTED) {
+    delay(500);
+  }
+  Serial.println(WiFi.localIP());
+
+  Firebase.begin(FIREBASE_HOST);
+  Firebase.auth(FIREBASE_TOKEN);
+
+  WiFiClientSecure wifiClient;
+  if (!wifiClient.connect(Firebase.host(), Firebase.port())) {
+    Serial.print("connected failed");
+  }
+  if (!wifiClient.verify(Firebase.fingerprint(), Firebase.host())) {
+    Serial.println("certificate verification failed");
+    return;
+  }
+
+  String req = Firebase.child("logs").push("{\".sv\": \"timestamp\"}");
+  Serial.println("request:");
+  Serial.println(req);
+  wifiClient.print(req);
+
+  Serial.println("response:");
+  while(wifiClient.connected() || wifiClient.available() > 0) {
+    String data = wifiClient.readStringUntil('\n');
+    Serial.println(data);
+  }  
 }
 
 void loop() {
-  int buttonState = digitalRead(pushButtonPin);
-  if (buttonState == 0 && buttonState != previousState) {
-    String record = Firebase.child("hits").push("{\".sv\": \"timestamp\"}");
-    Serial.print(record);
-  }
-  previousState = buttonState;
 }