Provide Apollo dynamic configuration center implementation. fixes #2825

apm-dist/release-docs/LICENSE

@@ -232,6 +232,7 @@ The text of each license is the standard Apache 2.0 license.
     Google: gprc-java 1.14.0: https://github.com/grpc/grpc-java, Apache 2.0
     Google: gprc-java 1.15.1: https://github.com/grpc/grpc-java, Apache 2.0
     Google: guava 20.0: https://github.com/google/guava , Apache 2.0
+    Google: guice 4.1.0: https://github.com/google/guice , Apache 2.0
     Google: gson 2.8.1: https://github.com/google/gson , Apache 2.0
     Google: opencensus-java 0.12.3: https://github.com/census-instrumentation/opencensus-java , Apache 2.0
     Google: proto-google-common-protos 0.1.9: https://github.com/googleapis/googleapis , Apache 2.0
@@ -318,6 +319,7 @@ The text of each license is the standard Apache 2.0 license.
     proto files from lyft/protoc-gen-validate: https://github.com/lyft/protoc-gen-validate Apache 2.0
     proto files from gogo/googleapis: https://github.com/gogo/googleapis Apache 2.0
     sundrio 0.9.2: https://github.com/sundrio/sundrio Apache 2.0
+    Ctripcorp: apollo 1.4.0: https://github.com/ctripcorp/apollo Apache 2.0
 
 ========================================================================
 MIT licenses
@@ -452,3 +454,9 @@ d3-voronoi      1.1.4:  https://github.com/d3/d3-voronoi        BSD-3-Clause
 d3-zoom 1.7.3:  https://github.com/d3/d3-zoom   BSD-3-Clause
 zrender 4.0.4:  https://github.com/ecomfe/zrender   BSD-3-Clause
 vue-i18n 8.10.0:  https://github.com/kazupon/vue-i18n   MIT
+
+========================================
+Public Domain licenses
+========================================
+aopalliance 1.0: http://aopalliance.sourceforge.net Public Domain
+

docs/en/setup/backend/dynamic-config.md

@@ -31,7 +31,21 @@ configuration:
     #clusterName: "default" # the name of current cluster, set the name if you want to upstream system known.  
 ```
 
-## Nacos DCS
+## Dynamic Configuration Apollo Implementation
+
+[Apollo](https://github.com/ctripcorp/apollo/) is also supported in DCS, to use it, just configured as follows:
+
+```yaml
+configuration:
+  apollo:
+    apolloMeta: <your apollo meta address>
+    apolloCluster: default
+    # apolloEnv: # defaults to null
+    appId: skywalking
+    period: 5
+```
+
+## Dynamic Configuration Nacos Implementation
 
 [Nacos](https://github.com/alibaba/nacos) is also supported in DCS, to use it, please configure as follows:
 

oap-server/pom.xml

@@ -76,7 +76,7 @@
         <commons-codec.version>1.11</commons-codec.version>
         <commons-lang3.version>3.7</commons-lang3.version>
         <simpleclient.version>0.6.0</simpleclient.version>
-
+        <apollo.version>1.4.0</apollo.version>
         <maven-docker-plugin.version>0.30.0</maven-docker-plugin.version>
         <nacos.version>1.0.0</nacos.version>
     </properties>
@@ -360,6 +360,12 @@
                 <artifactId>simpleclient</artifactId>
                 <version>${simpleclient.version}</version>
             </dependency>
+
+            <dependency>
+                <groupId>com.ctrip.framework.apollo</groupId>
+                <artifactId>apollo-client</artifactId>
+                <version>${apollo.version}</version>
+            </dependency>
             <dependency>
                 <groupId>com.alibaba.nacos</groupId>
                 <artifactId>nacos-client</artifactId>

oap-server/server-configuration/configuration-apollo/pom.xml

@@ -0,0 +1,173 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Licensed to the Apache Software Foundation (ASF) under one or more
+  ~ contributor license agreements.  See the NOTICE file distributed with
+  ~ this work for additional information regarding copyright ownership.
+  ~ The ASF licenses this file to You 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.
+  ~
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <artifactId>server-configuration</artifactId>
+        <groupId>org.apache.skywalking</groupId>
+        <version>6.2.0-SNAPSHOT</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <artifactId>configuration-apollo</artifactId>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>configuration-api</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>org.apache.skywalking</groupId>
+            <artifactId>library-client</artifactId>
+            <version>${project.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.ctrip.framework.apollo</groupId>
+            <artifactId>apollo-client</artifactId>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.springframework</groupId>
+                    <artifactId>spring-context</artifactId>
+                </exclusion>
+                <exclusion>
+                    <groupId>org.springframework.boot</groupId>
+                    <artifactId>spring-boot-autoconfigure</artifactId>
+                </exclusion>
+            </exclusions>
+        </dependency>
+    </dependencies>
+
+    <profiles>
+        <profile>
+            <id>CI-with-IT</id>
+            <build>
+                <plugins>
+                    <plugin>
+                        <groupId>io.fabric8</groupId>
+                        <artifactId>docker-maven-plugin</artifactId>
+                        <configuration>
+                            <sourceMode>all</sourceMode>
+                            <showLogs>true</showLogs>
+                            <logDate>default</logDate>
+                            <verbose>true</verbose>
+                            <imagePullPolicy>IfNotPresent</imagePullPolicy>
+                            <images>
+                                <image>
+                                    <name>mysql:5.7</name>
+                                    <alias>apollo-db</alias>
+                                    <run>
+                                        <env>
+                                            <TZ>Asia/Shanghai</TZ>
+                                            <MYSQL_ALLOW_EMPTY_PASSWORD>yes</MYSQL_ALLOW_EMPTY_PASSWORD>
+                                        </env>
+                                        <namingStrategy>none</namingStrategy>
+                                        <volumes>
+                                            <bind>
+                                                <volume>
+                                                    src/test/resources/docker/docker-entrypoint-initdb.d:/docker-entrypoint-initdb.d
+                                                </volume>
+                                            </bind>
+                                        </volumes>
+                                        <wait>
+                                            <log>ready for connections</log>
+                                            <time>600000</time>
+                                        </wait>
+                                    </run>
+                                </image>
+                                <image>
+                                    <name>kezhenxu94/apollo:1.2</name>
+                                    <alias>apollo-config-and-portal</alias>
+                                    <run>
+                                        <namingStrategy>none</namingStrategy>
+                                        <dependsOn>
+                                            <container>apollo-db</container>
+                                        </dependsOn>
+                                        <links>
+                                            <link>apollo-db</link>
+                                        </links>
+                                        <ports>
+                                            <port>+apollo.portal.host:apollo.portal.port:8070</port>
+                                            <port>+apollo.meta.host:apollo.meta.port:8080</port>
+                                        </ports>
+                                        <wait>
+                                            <log>Portal started. You can visit</log>
+                                            <time>2400000</time>
+                                        </wait>
+                                    </run>
+                                </image>
+                            </images>
+                        </configuration>
+                        <executions>
+                            <execution>
+                                <id>start</id>
+                                <phase>pre-integration-test</phase>
+                                <goals>
+                                    <goal>start</goal>
+                                </goals>
+                            </execution>
+                            <execution>
+                                <id>stop</id>
+                                <phase>post-integration-test</phase>
+                                <goals>
+                                    <goal>stop</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                    <plugin>
+                        <groupId>org.apache.maven.plugins</groupId>
+                        <artifactId>maven-failsafe-plugin</artifactId>
+                        <configuration>
+                            <systemPropertyVariables>
+                                <apollo.portal.host>
+                                    ${apollo.portal.host}
+                                </apollo.portal.host>
+                                <apollo.portal.port>
+                                    ${apollo.portal.port}
+                                </apollo.portal.port>
+                                <apollo.meta.host>
+                                    ${apollo.meta.host}
+                                </apollo.meta.host>
+                                <apollo.meta.port>
+                                    ${apollo.meta.port}
+                                </apollo.meta.port>
+                                <apollo.configService>
+                                    http://${apollo.meta.host}:${apollo.meta.port}
+                                </apollo.configService>
+                            </systemPropertyVariables>
+                        </configuration>
+                        <executions>
+                            <execution>
+                                <goals>
+                                    <goal>integration-test</goal>
+                                    <goal>verify</goal>
+                                </goals>
+                            </execution>
+                        </executions>
+                    </plugin>
+                </plugins>
+            </build>
+        </profile>
+    </profiles>
+</project>

oap-server/server-configuration/configuration-apollo/src/main/java/org/apache/skywalking/oap/server/configuration/apollo/ApolloConfigWatcherRegister.java

@@ -0,0 +1,70 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.skywalking.oap.server.configuration.apollo;
+
+import com.ctrip.framework.apollo.Config;
+import com.ctrip.framework.apollo.ConfigService;
+import com.google.common.base.Strings;
+import org.apache.skywalking.oap.server.configuration.api.ConfigTable;
+import org.apache.skywalking.oap.server.configuration.api.ConfigWatcherRegister;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.Set;
+
+/**
+ * @author kezhenxu94
+ */
+public class ApolloConfigWatcherRegister extends ConfigWatcherRegister {
+    private static final Logger LOGGER = LoggerFactory.getLogger(ApolloConfigWatcherRegister.class);
+
+    private final Config configReader;
+
+    public ApolloConfigWatcherRegister(ApolloConfigurationCenterSettings settings) {
+        super(settings.getPeriod());
+
+        final String namespace = settings.getNamespace();
+
+        final boolean isDefaultNamespace = Strings.isNullOrEmpty(namespace);
+
+        if (isDefaultNamespace) {
+            this.configReader = ConfigService.getAppConfig();
+            if (LOGGER.isInfoEnabled()) {
+                LOGGER.info("Read dynamic configs from Apollo default namespace");
+            }
+        } else {
+            this.configReader = ConfigService.getConfig(namespace);
+            if (LOGGER.isInfoEnabled()) {
+                LOGGER.info("Read dynamic configs from Apollo namespace: {}", namespace);
+            }
+        }
+    }
+
+    @Override
+    public ConfigTable readConfig(Set<String> keys) {
+        final ConfigTable configTable = new ConfigTable();
+
+        for (final String name : keys) {
+            final String value = configReader.getProperty(name, null);
+            configTable.add(new ConfigTable.ConfigItem(name, value));
+        }
+
+        return configTable;
+    }
+}