Added example for cloud messaging.

Author: ed7coyne

examples/FirebaseCloudMessaging_Send_ESP8266/FirebaseCloudMessaging_Send_ESP8266.ino

@@ -0,0 +1,62 @@
+//
+// 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.
+//
+
+// FirebaseCloudMessaging_Send_ESP8266 is a sample that shows sending
+// messages to firebase.
+
+#include <ESP8266WiFi.h>
+
+#include <FirebaseCloudMessaging.h>
+#include <FirebaseHttpClient.h>
+
+// Set these to run example.
+#define WIFI_SSID "SSID"
+#define WIFI_PASSWORD "PASSWORD"
+
+#define SERVER_KEY "key_from_dashboard"
+#define CLIENT_REGISTRATION_ID "key_from_client_after_registration"
+
+void setup() {
+  Serial.begin(9600);
+
+  // connect to wifi.
+  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
+  Serial.print("connecting");
+  while (WiFi.status() != WL_CONNECTED) {
+    Serial.print(".");
+    delay(500);
+  }
+  Serial.println();
+  Serial.print("connected: ");
+  Serial.println(WiFi.localIP());
+
+  FirebaseCloudMessaging fcm(SERVER_KEY);
+  FirebaseCloudMessage message =
+  	FirebaseCloudMessage::SimpleNotification("Hello World!", "What's happening?");
+  FirebaseError error = fcm.SendMessageToUser(CLIENT_REGISTRATION_ID, message);
+  if (error) {
+    Serial.print("Error:");
+    Serial.print(error.code());
+    Serial.print(" :: ");
+    Serial.println(error.message().c_str());
+  } else {
+    Serial.println("Sent OK!");
+  }
+}
+
+void loop() {
+}
+