From 7450f03902f2d5da9871904ff910b8bee8c52a2d Mon Sep 17 00:00:00 2001
From: qibaoguang <qibaoguang@gmail.com>
Date: Fri, 6 Mar 2015 23:09:51 +0800
Subject: [PATCH] Update 49.1. Binding to services.md

---
 .../49.1. Binding to services.md              | 23 +++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/VI. Deploying to the cloud/49.1. Binding to services.md b/VI. Deploying to the cloud/49.1. Binding to services.md
index e69de29..a32fc5e 100644
--- a/VI. Deploying to the cloud/49.1. Binding to services.md	
+++ b/VI. Deploying to the cloud/49.1. Binding to services.md	
@@ -0,0 +1,23 @@
+### 49.1. 绑定服务
+
+默认情况下，运行应用的元数据和服务连接信息被暴露为应用的环境变量（比如，$VCAP_SERVICES）。采用这种架构的原因是因为Cloud Foundry多语言特性（任何语言和平台都支持作为buildpack）。进程级别的环境变量是语言无关（language agnostic）的。
+
+环境变量并不总是有利于设计最简单的API，所以Spring Boot自动提取它们，然后将这些数据导入能够通过Spring `Environment`抽象访问的属性里：
+```java
+@Component
+class MyBean implements EnvironmentAware {
+
+    private String instanceId;
+
+    @Override
+    public void setEnvironment(Environment environment) {
+        this.instanceId = environment.getProperty("vcap.application.instance_id");
+    }
+
+    // ...
+
+}
+```
+所有的Cloud Foundry属性都以vcap作为前缀。你可以使用vcap属性获取应用信息（比如应用的公共URL）和服务信息（比如数据库证书）。具体参考VcapApplicationListener Javadoc。
+
+**注**：[Spring Cloud Connectors](http://cloud.spring.io/spring-cloud-connectors/)项目很适合比如配置数据源的任务。Spring Boot提供自动配置支持和一个`spring-boot-starter-cloud-connectors` starter POM。