6.x的时候还有免费版，7.x就没有免费版了，只有试用版，而且只是三十天。
主要流程：
复制出 x-pack-core-7.15.1.jar —->反编译这个jar包里的两个文件(LicenseVerifier.class，XPackBuild.class) —->使用es环境的java编译LicenseVerifier.class，XPackBuild.class—->替换原x-pack-core-7.15.1.jar里的两个class文件 —->重启elasticsearch—->申请试用版获取Lisence，修改License里的版本和使用结束日期—->导入Lisence—->Done
一、复制出x-pack-core-7.15.1.jar
这个文件centos环境的路径是：/usr/share/elasticsearch/modules/x-pack-core/x-pack-core-7.15.1.jar
二、反编译LicenseVerifier.class，XPackBuild.class
这个具体实现就不多说了。
三、修改反编译后的LicenseVerifier.java，XPackBuild.java
LicenseVerifier.java修改如下：
package org.elasticsearch.license;
import java.nio.*;
import org.elasticsearch.common.bytes.*;
import java.security.*;
import java.util.*;
import org.elasticsearch.common.xcontent.*;
import org.apache.lucene.util.*;
import org.elasticsearch.core.internal.io.*;
import java.io.*;
public class LicenseVerifier
{
public static boolean verifyLicense(final License license, final byte[] publicKeyData) {
/* 注释掉这一大段
byte[] signedContent = null;
byte[] publicKeyFingerprint = null;
try {
final byte[] signatureBytes = Base64.getDecoder().decode(license.signature());
final ByteBuffer byteBuffer = ByteBuffer.wrap(signatureBytes);
final int version = byteBuffer.getInt();
final int magicLen = byteBuffer.getInt();
final byte[] magic = new byte[magicLen];
byteBuffer.get(magic);
final int hashLen = byteBuffer.getInt();
publicKeyFingerprint = new byte[hashLen];
byteBuffer.get(publicKeyFingerprint);
final int signedContentLen = byteBuffer.getInt();
signedContent = new byte[signedContentLen];
byteBuffer.get(signedContent);
final XContentBuilder contentBuilder = XContentFactory.contentBuilder(XContentType.JSON);
license.toXContent(contentBuilder, (ToXContent.Params)new ToXContent.MapParams((Map)Collections.singletonMap("license_spec_view", "true")));
final Signature rsa = Signature.getInstance("SHA512withRSA");
rsa.initVerify(CryptUtils.readPublicKey(publicKeyData));
final BytesRefIterator iterator = BytesReference.bytes(contentBuilder).iterator();
BytesRef ref;
while ((ref = iterator.next()) != null) {
rsa.update(ref.bytes, ref.offset, ref.length);
}
return rsa.verify(signedContent);
}
catch (IOException ex) {}
catch (NoSuchAlgorithmException ex2) {}
catch (SignatureException ex3) {}
catch (InvalidKeyException e) {
throw new IllegalStateException(e);
}
finally {
if (signedContent != null) {
Arrays.fill(signedContent, (byte)0);
}
}
*/
return true; // 增加这行
}
public static boolean verifyLicense(final License license) {
/* 注释掉这一大段
byte[] publicKeyBytes;
try {
final InputStream is = LicenseVerifier.class.getResourceAsStream("/public.key");
try {
final ByteArrayOutputStream out = new ByteArrayOutputStream();
Streams.copy(is, (OutputStream)out);
publicKeyBytes = out.toByteArray();
if (is != null) {
is.close();
}
}
catch (Throwable t) {
if (is != null) {
try {
is.close();
}
catch (Throwable t2) {
t.addSuppressed(t2);
}
}
throw t;
}
}
catch (IOException ex) {
throw new IllegalStateException(ex);
}
return verifyLicense(license, publicKeyBytes);
*/
return true; // 增加这行
}
}XPackBuild.java修改如下：
package org.elasticsearch.xpack.core;
import org.elasticsearch.common.io.*;
import java.net.*;
import org.elasticsearch.common.*;
import java.nio.file.*;
import java.io.*;
import java.util.jar.*;
public class XPackBuild
{
public static final XPackBuild CURRENT;
private String shortHash;
private String date;
@SuppressForbidden(reason = "looks up path of xpack.jar directly")
static Path getElasticsearchCodebase() {
final URL url = XPackBuild.class.getProtectionDomain().getCodeSource().getLocation();
try {
return PathUtils.get(url.toURI());
}
catch (URISyntaxException bogus) {
throw new RuntimeException(bogus);
}
}
XPackBuild(final String shortHash, final String date) {
this.shortHash = shortHash;
this.date = date;
}
public String shortHash() {
return this.shortHash;
}
public String date() {
return this.date;
}
static {
final Path path = getElasticsearchCodebase();
String shortHash = null;
String date = null;
Label_0109: {
/* 注释掉这一大段即可
if (path.toString().endsWith(".jar")) {
try {
final JarInputStream jar = new JarInputStream(Files.newInputStream(path, new OpenOption[0]));
try {
final Manifest manifest = jar.getManifest();
shortHash = manifest.getMainAttributes().getValue("Change");
date = manifest.getMainAttributes().getValue("Build-Date");
jar.close();
}
catch (Throwable t) {
try {
jar.close();
}
catch (Throwable t2) {
t.addSuppressed(t2);
}
throw t;
}
break Label_0109;
}
catch (IOException e) {
throw new RuntimeException(e);
}
}
*/
shortHash = "Unknown";
date = "Unknown";
}
CURRENT = new XPackBuild(shortHash, date);
}
}修改完后，使用ES环境的java编译：
ES_HOME="/usr/share/elasticsearch"
ES_JAR=$(cd $ES_HOME && ls lib/elasticsearch-[0-9]*.jar)
ESCORE_JAR=$(cd $ES_HOME && ls lib/elasticsearch-core-*.jar)
LUCENE_JAR=$(cd $ES_HOME && ls lib/lucene-core-*.jar)
XPACK_JAR=$(cd $ES_HOME && ls modules/x-pack-core/x-pack-core-*.jar)
javac -cp "${ES_HOME}/${ES_JAR}:${ES_HOME}/${LUCENE_JAR}:${ES_HOME}/${XPACK_JAR}:${ES_HOME}/${ESCORE_JAR}" LicenseVerifier.java
javac -cp "${ES_HOME}/${ES_JAR}:${ES_HOME}/${LUCENE_JAR}:${ES_HOME}/${XPACK_JAR}:${ES_HOME}/${ESCORE_JAR}" XPackBuild.java四、替换原x-pack-core-7.15.1.jar里的两个class文件
编译完之后，用压缩文件打开 x-pack-core-7.15.1.jar，然后把x-pack-core-7.15.1.jar文件覆盖/usr/share/elasticsearch/modules/x-pack-core/x-pack-core-7.15.1.jar，然后重启elasticserch
五、去官网申请License
申请下来的License中的type改为platinum，将expiry_date_in_millis延长N年时间：
六、导入修改过的lisence.json
最终如下：
|
|
|
|
|
|
|
Done