blob: fb7798b8edffd8b30b886eb68aeb418069d39732 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.vespa.athenz.identity;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import javax.net.ssl.SSLContext;
import java.io.IOException;
import java.io.UncheckedIOException;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Supplier;
/**
* A thread-safe http client wrapper on Apache's {@link HttpClient} that handles TLS client authentication using {@link ServiceIdentityProvider}.
*
* @author bjorncs
*/
public class SiaBackedApacheHttpClient implements AutoCloseable {
private final Object clientReferenceLock = new Object();
private final Supplier<SSLContext> sslContextSupplier;
private final HttpClientFactory httpClientFactory;
private HttpClientHolder client;
public SiaBackedApacheHttpClient(ServiceIdentityProvider identityProvider,
HttpClientFactory httpClientFactory) {
this(identityProvider::getIdentitySslContext, httpClientFactory);
}
public SiaBackedApacheHttpClient(SSLContext sslContext,
HttpClientFactory httpClientFactory) {
this(() -> sslContext, httpClientFactory);
}
public SiaBackedApacheHttpClient(Supplier<SSLContext> sslContextSupplier,
HttpClientFactory httpClientFactory) {
this.sslContextSupplier = sslContextSupplier;
this.httpClientFactory = httpClientFactory;
synchronized (clientReferenceLock) {
this.client = new HttpClientHolder(httpClientFactory, sslContextSupplier);
}
}
public <T> T execute(HttpUriRequest request, ResponseHandler<T> responseHandler) {
HttpClientHolder client = getClient();
try {
// Note: Apache http client will handle response/connection cleanup for this overload of execute().
return client.apacheClient.execute(request, responseHandler);
} catch (IOException e) {
throw new UncheckedIOException(e);
} finally {
client.release();
}
}
private HttpClientHolder getClient() {
HttpClientHolder client;
synchronized (clientReferenceLock) {
if (sslContextSupplier.get() != this.client.sslContext) {
this.client.release();
this.client = new HttpClientHolder(httpClientFactory, sslContextSupplier);
}
client = this.client;
}
return client.refer();
}
@Override
public void close() {
HttpClientHolder client;
synchronized (clientReferenceLock) {
client = this.client;
}
client.release();
}
private static class HttpClientHolder {
final Supplier<SSLContext> sslContextSupplier;
final CloseableHttpClient apacheClient;
final SSLContext sslContext;
final AtomicInteger referenceCount = new AtomicInteger(1); // Owner's reference implicitly counted
HttpClientHolder(HttpClientFactory clientBuilder, Supplier<SSLContext> sslContextSupplier) {
SSLContext sslContext = sslContextSupplier.get();
this.sslContextSupplier = sslContextSupplier;
this.apacheClient = clientBuilder.createHttpClient(sslContext);
this.sslContext = sslContext;
}
HttpClientHolder refer() {
if (referenceCount.get() == 0) throw new IllegalStateException("Client already closed!");
referenceCount.incrementAndGet();
return this;
}
void release() {
if (referenceCount.decrementAndGet() == 0) {
try {
apacheClient.close();
} catch (IOException e) {
throw new UncheckedIOException(e);
}
}
}
}
/**
* A factory that returns a new instance of {@link CloseableHttpClient}. The implementor is responsible for configuring the {@link SSLContext}, e.g. using {@link HttpClientBuilder#setSSLContext(SSLContext)}.
*/
@FunctionalInterface
public interface HttpClientFactory {
CloseableHttpClient createHttpClient(SSLContext sslContext);
}
}
|
