Java tutorial
/* * Copyright 2015 predic8 GmbH, www.predic8.com * 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 com.predic8.membrane.core.interceptor.apimanagement.apiconfig; import com.predic8.membrane.annot.MCAttribute; import com.predic8.membrane.annot.MCElement; import com.predic8.membrane.core.Router; import com.predic8.membrane.core.cloud.ExponentialBackoff; import com.predic8.membrane.core.cloud.etcd.EtcdNodeInformation; import com.predic8.membrane.core.cloud.etcd.EtcdRequest; import com.predic8.membrane.core.cloud.etcd.EtcdResponse; import com.predic8.membrane.core.config.spring.BaseLocationApplicationContext; import com.predic8.membrane.core.interceptor.Interceptor; import com.predic8.membrane.core.interceptor.administration.AdminConsoleInterceptor; import com.predic8.membrane.core.interceptor.apimanagement.ApiManagementConfiguration; import com.predic8.membrane.core.rules.AbstractServiceProxy; import com.predic8.membrane.core.rules.Rule; import com.predic8.membrane.core.rules.ServiceProxy; import org.apache.commons.io.IOUtils; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.springframework.beans.BeansException; import org.springframework.beans.factory.DisposableBean; import org.springframework.beans.factory.InitializingBean; import org.springframework.context.ApplicationContext; import org.springframework.context.ApplicationContextAware; import org.springframework.context.Lifecycle; import org.springframework.context.event.ContextRefreshedEvent; import org.springframework.context.event.EventListener; import java.io.IOException; import java.net.InetAddress; import java.net.MalformedURLException; import java.net.URL; import java.net.UnknownHostException; @MCElement(name = "etcdRegistryApiConfig") public class EtcdRegistryApiConfig implements Lifecycle, ApplicationContextAware, ApiConfig, DisposableBean { private static final Log log = LogFactory.getLog(EtcdRegistryApiConfig.class.getName()); private ApplicationContext context; private ApiManagementConfiguration amc; private String url; private String membraneId; private String baseKeyPrefix = "/membrane/"; private int ttl = 300; private int retryDelayMin = 10 * 1000; private int retryDelayMax = 10 * 60 * 1000; private double expDelayFactor = 2.0d; Thread publisher = new Thread(new Runnable() { int sleepTime = (ttl - 10) * 1000; @Override public void run() { try { boolean connectionLost = false; while (true) { String baseKey = baseKeyPrefix + membraneId; EtcdResponse respTTLDirRefresh = EtcdRequest.create(url, baseKey, "").refreshTTL(ttl) .sendRequest(); if (!respTTLDirRefresh.is2XX()) { log.warn("Could not contact etcd at " + url); connectionLost = true; } Thread.sleep(sleepTime); if (connectionLost) { log.warn("Connection lost to etcd"); ExponentialBackoff.retryAfter(retryDelayMin, retryDelayMax, expDelayFactor, "Republish from thread after failed ttl refresh", jobPublisher); } } } catch (InterruptedException ignored) { } } }); ExponentialBackoff.Job jobPublisher = new ExponentialBackoff.Job() { @Override public boolean run() throws Exception { return publishToEtcd(); } }; private boolean publishToEtcd() { String baseKey = baseKeyPrefix + membraneId; EtcdResponse respPublishApiUrl = EtcdRequest.create(url, baseKey, "/apiconfig").setValue("url", "") .sendRequest(); if (!respPublishApiUrl.is2XX()) { System.out.println(respPublishApiUrl.getBody()); return false; } EtcdResponse respPublishApiFingerprint = EtcdRequest.create(url, baseKey, "/apiconfig") .setValue("fingerprint", "").sendRequest(); if (!respPublishApiFingerprint.is2XX()) { System.out.println(respPublishApiFingerprint.getBody()); return false; } EtcdNodeInformation adminConsole = findAdminConsole(); EtcdResponse respPublishEndpointName = EtcdRequest.create(url, baseKey, "/endpoint") .setValue("name", adminConsole.getName()).sendRequest(); if (!respPublishEndpointName.is2XX()) { System.out.println(respPublishEndpointName.getBody()); return false; } EtcdResponse respPublishEndpointHost = EtcdRequest.create(url, baseKey, "/endpoint") .setValue("host", adminConsole.getTargetHost()).sendRequest(); if (!respPublishEndpointHost.is2XX()) { System.out.println(respPublishEndpointHost.getBody()); return false; } EtcdResponse respPublishEndpointPort = EtcdRequest.create(url, baseKey, "/endpoint") .setValue("port", adminConsole.getTargetPort()).sendRequest(); if (!respPublishEndpointPort.is2XX()) { System.out.println(respPublishEndpointPort.getBody()); return false; } return true; } private EtcdNodeInformation findAdminConsole() { Object routerObj = context.getBean(Router.class); if (routerObj == null) throw new RuntimeException("Router not found, cannot publish admin console"); Router router = (Router) routerObj; for (Rule r : router.getRuleManager().getRules()) { if (!(r instanceof AbstractServiceProxy)) continue; for (Interceptor i : r.getInterceptors()) { if (i instanceof AdminConsoleInterceptor) { String name = r.getName(); String host = ((ServiceProxy) r).getExternalHostname(); if (host == null) host = getLocalHostname(); String port = Integer.toString(((AbstractServiceProxy) r).getPort()); EtcdNodeInformation node = new EtcdNodeInformation(null, null, host, port, name); return node; } } } throw new RuntimeException( "Admin console not found but is needed. Add a service proxy with an admin console."); } @Override public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.context = applicationContext; } @Override public void start() { Object routerObj = context.getBean(Router.class); if (routerObj == null) throw new RuntimeException("Router cannot be found"); Router router = (Router) routerObj; membraneId = router.getId(); try { log.info("Started membrane publishing"); ExponentialBackoff.retryAfter(retryDelayMin, retryDelayMax, expDelayFactor, "First publish from thread", jobPublisher); } catch (InterruptedException ignored) { } initAmc(); if (!publisher.isAlive()) { publisher.start(); } } public void initAmc() { String workingDir = ((BaseLocationApplicationContext) context).getBaseLocation(); String etcdUrlForAmc = null; URL u = null; try { u = new URL(getUrl()); } catch (MalformedURLException e) { try { u = new URL("http://" + getUrl()); } catch (MalformedURLException ignored) { } } if (u == null) { log.error("Url malformed: " + getUrl()); } etcdUrlForAmc = "etcd://" + u.getHost() + ":" + u.getPort(); amc = new ApiManagementConfiguration(workingDir, etcdUrlForAmc, membraneId); } @Override public void stop() { amc.shutdown(); } @Override public boolean isRunning() { return false; } public String getUrl() { return url; } /** * @description the url to where details are published * @default http://localhost:4001 */ @MCAttribute public void setUrl(String url) { this.url = url; } public int getTtl() { return ttl; } /** * @description ttl in seconds * @default 300 */ @MCAttribute public void setTtl(int ttl) { this.ttl = ttl; } @Override public ApiManagementConfiguration getConfiguration() { return amc; } @Override public void destroy() throws Exception { stop(); } public String getLocalHostname() { try { return InetAddress.getLocalHost().getHostName(); } catch (UnknownHostException e) { try { return IOUtils.toString(Runtime.getRuntime().exec("hostname").getInputStream()); } catch (IOException e1) { e1.printStackTrace(); return "localhost"; } } } }