Merge remote-tracking branch 'upstream/master'

# Conflicts:
#	pom.xml
#	spring-cloud-alibaba-dependencies/pom.xml
#	spring-cloud-alibaba-examples/nacos-example/nacos-discovery-example/pom.xml

spring-cloud-alibaba-examples/env-extension/src/main/java/org/springframework/alicloud/env/extension/ImportExtraConfig.java

@@ -0,0 +1,16 @@
+package org.springframework.alicloud.env.extension;
+
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface ImportExtraConfig {
+
+    String[] name() default "";
+}

spring-cloud-alibaba-examples/env-extension/src/main/java/org/springframework/alicloud/env/extension/LoadExtraConfigApplicationListener.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright (C) 2019 the original author or authors.
+ *
+ * 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.
+ */
+package org.springframework.alicloud.env.extension;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.context.event.ApplicationEnvironmentPreparedEvent;
+import org.springframework.context.ApplicationListener;
+import org.springframework.core.env.PropertiesPropertySource;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.Properties;
+
+/**
+ * @author pbting
+ * @date 2019-01-09 9:00 PM
+ */
+public class LoadExtraConfigApplicationListener implements ApplicationListener<ApplicationEnvironmentPreparedEvent> {
+
+    @Override
+    public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
+        SpringApplication springApplication = event.getSpringApplication();
+        Class clazz = springApplication.getMainApplicationClass();
+        if (!clazz.isAnnotationPresent(ImportExtraConfig.class)) {
+            return;
+        }
+        ImportExtraConfig annotation = (ImportExtraConfig) clazz
+                .getAnnotation(ImportExtraConfig.class);
+
+        String[] extraConfig = annotation.name();
+
+        if (extraConfig == null || extraConfig.length == 0) {
+            return;
+        }
+
+        for (String config : extraConfig) {
+            try {
+                Properties properties = new Properties();
+                properties.load(new FileInputStream(config));
+                event.getEnvironment().getPropertySources()
+                        .addFirst(new PropertiesPropertySource(config, properties));
+            }
+            catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+}

spring-cloud-alibaba-examples/env-extension/src/main/resources/META-INF/spring.factories

@@ -0,0 +1,2 @@
+org.springframework.context.ApplicationListener=\
+  org.springframework.alicloud.env.extension.LoadExtraConfigApplicationListener