/**
* 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.camel.catalog.nexus;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A base class for scanning and index Maven Nexus repositories for artifacts which can be added to catalogs.
*/
public abstract class BaseNexusRepository {
final Logger logger = LoggerFactory.getLogger(getClass());
boolean log;
private final Set<NexusArtifactDto> indexedArtifacts = new LinkedHashSet<>();
private volatile ScheduledExecutorService executorService;
private AtomicBoolean started = new AtomicBoolean();
private int initialDelay = 10;
private int delay = 60;
private String nexusUrl = "http://nexus/service/local/data_index";
private String classifier;
public BaseNexusRepository(String classifier) {
this.classifier = classifier;
}
/**
* Sets whether to log errors and warnings to System.out.
* By default nothing is logged.
*/
public void setLog(boolean log) {
this.log = log;
}
public String getNexusUrl() {
return nexusUrl;
}
/**
* The URL to the Nexus repository to query. The syntax should be <tt>http://nexus/service/local/data_index</tt>, where
* nexus is the hostname.
*/
public void setNexusUrl(String nexusUrl) {
this.nexusUrl = nexusUrl;
}
public int getInitialDelay() {
return initialDelay;
}
/**
* Delay in seconds before the initial (first) scan.
*/
public void setInitialDelay(int initialDelay) {
this.initialDelay = initialDelay;
}
public int getDelay() {
return delay;
}
/**
* Delay in seconds between scanning.
*/
public void setDelay(int delay) {
this.delay = delay;
}
public String getClassifier() {
return classifier;
}
/**
* Classifier to index. Should be either <tt>component</tt>, or <tt>connector</tt>
*/
public void setClassifier(String classifier) {
this.classifier = classifier;
}
/**
* Starts the Nexus indexer.
*/
public void start() {
if (nexusUrl == null || nexusUrl.isEmpty()) {
logger.warn("Nexus service not found. Indexing Nexus is not enabled!");
return;
}
if (!started.compareAndSet(false, true)) {
logger.info("NexusRepository is already started");
return;
}
logger.info("Starting NexusRepository to scan every {} seconds", delay);
executorService = Executors.newScheduledThreadPool(1);
executorService.scheduleWithFixedDelay(() -> {
try {
logger.debug("Indexing Nexus {} +++ start +++", nexusUrl);
indexNexus();
} catch (Throwable e) {
if (e.getMessage().contains("UnknownHostException")) {
// less noise if its unknown host
logger.warn("Error indexing Nexus " + nexusUrl + " due unknown hosts: " + e.getMessage());
} else {
logger.warn("Error indexing Nexus " + nexusUrl + " due " + e.getMessage(), e);
}
} finally {
logger.debug("Indexing Nexus {} +++ end +++", nexusUrl);
}
}, initialDelay, delay, TimeUnit.SECONDS);
}
/**
* Stops the Nexus indexer.
*/
public void stop() {
logger.info("Stopping NexusRepository");
if (executorService != null) {
executorService.shutdownNow();
executorService = null;
}
indexedArtifacts.clear();
started.set(false);
}
/**
* Callback when new artifacts has been discovered in Nexus
*/
abstract void onNewArtifacts(Set<NexusArtifactDto> newArtifacts);
protected URL createNexusUrl() throws MalformedURLException {
String query = nexusUrl + "?q=" + getClassifier();
return new URL(query);
}
/**
* Creates the url to download the artifact.
*
* @param dto the artifact
* @return the url to download
*/
protected String createArtifactURL(NexusArtifactDto dto) {
return dto.getArtifactLink();
}
/**
* Runs the task to index nexus for new artifacts
*/
protected void indexNexus() throws Exception {
// must have q parameter so use component to find all component
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true);
factory.setIgnoringElementContentWhitespace(true);
factory.setIgnoringComments(true);
DocumentBuilder documentBuilder = factory.newDocumentBuilder();
URL url = createNexusUrl();
InputStream is = url.openStream();
try {
Document dom = documentBuilder.parse(is);
XPathFactory xpFactory = XPathFactory.newInstance();
XPath exp = xpFactory.newXPath();
NodeList list = (NodeList) exp.evaluate("//data/artifact", dom, XPathConstants.NODESET);
Set<NexusArtifactDto> newArtifacts = new LinkedHashSet<>();
for (int i = 0; i < list.getLength(); i++) {
Node node = list.item(i);
String g = getNodeText(node.getChildNodes(), "groupId");
String a = getNodeText(node.getChildNodes(), "artifactId");
String v = getNodeText(node.getChildNodes(), "version");
String l = getNodeText(node.getChildNodes(), "artifactLink");
if (g != null & a != null & v != null & l != null) {
NexusArtifactDto dto = new NexusArtifactDto();
dto.setGroupId(g);
dto.setArtifactId(a);
dto.setVersion(v);
dto.setArtifactLink(l);
logger.debug("Found: {}:{}:{}", dto.getGroupId(), dto.getArtifactId(), dto.getVersion());
// is it a new artifact
boolean newArtifact = true;
for (NexusArtifactDto existing : indexedArtifacts) {
if (existing.getGroupId().equals(dto.getGroupId())
&& existing.getArtifactId().equals(dto.getArtifactId())
&& existing.getVersion().equals(dto.getVersion())) {
newArtifact = false;
break;
}
}
if (newArtifact) {
newArtifacts.add(dto);
}
}
}
// if there is any new artifacts then process them
if (!newArtifacts.isEmpty()) {
onNewArtifacts(newArtifacts);
}
} finally {
close(is);
}
}
private static String getNodeText(NodeList list, String name) {
for (int i = 0; i < list.getLength(); i++) {
Node child = list.item(i);
if (name.equals(child.getNodeName())) {
return child.getTextContent();
}
}
return null;
}
private static void close(Closeable... closeables) {
for (Closeable c : closeables) {
try {
if (c != null) {
c.close();
}
} catch (IOException e) {
// ignore
}
}
}
}