andreacavalli/netty5
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Introduce BrotliEncoder (#11256)

Browse Source 
Motivation:
Currently, Netty only has BrotliDecoder which can decode Brotli encoded data. However, BrotliEncoder is missing which will encode normal data to Brotli encoded data.

Modification:
Added BrotliEncoder and CompressionOption

Result:
Fixes #6899.

Co-authored-by: Norman Maurer <norman_maurer@apple.com>
This commit is contained in:
Aayush Atharva 2021-07-08 15:21:27 +05:30 committed by Norman Maurer
parent 95a59af549
commit 55c4e2ca82
19 changed files with 1094 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
NOTICE.txt
View File

@ -254,3 +254,11 @@ This private header is also used by Apple's open source
* license/LICENSE.dnsinfo.txt (Apple Public Source License 2.0)
* HOMEPAGE:
* https://www.opensource.apple.com/source/configd/configd-453.19/dnsinfo/dnsinfo.h
This product optionally depends on 'Brotli4j', Brotli compression and
decompression for Java., which can be obtained at:
* LICENSE:
* license/LICENSE.brotli4j.txt (Apache License 2.0)
* HOMEPAGE:
* https://github.com/hyperxpro/Brotli4j

2
codec-http/pom.xml
View File

@ -74,7 +74,7 @@
<dependency>
<groupId>com.aayushatharva.brotli4j</groupId>
<artifactId>brotli4j</artifactId>
<scope>test</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>com.aayushatharva.brotli4j</groupId>

200
codec-http/src/main/java/io/netty/handler/codec/http/HttpContentCompressor.java
View File

@ -17,8 +17,15 @@ package io.netty.handler.codec.http;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.embedded.EmbeddedChannel;
import io.netty.handler.codec.compression.Brotli;
import io.netty.handler.codec.compression.BrotliEncoder;
import io.netty.handler.codec.compression.ZlibCodecFactory;
import io.netty.handler.codec.compression.ZlibWrapper;
import io.netty.handler.codec.compression.BrotliOptions;
import io.netty.handler.codec.compression.CompressionOptions;
import io.netty.handler.codec.compression.DeflateOptions;
import io.netty.handler.codec.compression.GzipOptions;
import io.netty.handler.codec.compression.StandardCompressionOptions;
import io.netty.util.internal.ObjectUtil;
/**
@ -30,6 +37,11 @@ import io.netty.util.internal.ObjectUtil;
*/
public class HttpContentCompressor extends HttpContentEncoder {
private final boolean supportsCompressionOptions;
private final BrotliOptions brotliOptions;
private final GzipOptions gzipOptions;
private final DeflateOptions deflateOptions;
private final int compressionLevel;
private final int windowBits;
private final int memLevel;
@ -53,6 +65,7 @@ public class HttpContentCompressor extends HttpContentEncoder {
* best compression. {@code 0} means no compression. The default
* compression level is {@code 6}.
*/
@Deprecated
public HttpContentCompressor(int compressionLevel) {
this(compressionLevel, 15, 8, 0);
}
@ -76,6 +89,7 @@ public class HttpContentCompressor extends HttpContentEncoder {
* memory. Larger values result in better and faster compression
* at the expense of memory usage. The default value is {@code 8}
*/
@Deprecated
public HttpContentCompressor(int compressionLevel, int windowBits, int memLevel) {
this(compressionLevel, windowBits, memLevel, 0);
}
@ -103,11 +117,80 @@ public class HttpContentCompressor extends HttpContentEncoder {
* body exceeds the threshold. The value should be a non negative
* number. {@code 0} will enable compression for all responses.
*/
@Deprecated
public HttpContentCompressor(int compressionLevel, int windowBits, int memLevel, int contentSizeThreshold) {
this.compressionLevel = ObjectUtil.checkInRange(compressionLevel, 0, 9, "compressionLevel");
this.windowBits = ObjectUtil.checkInRange(windowBits, 9, 15, "windowBits");
this.memLevel = ObjectUtil.checkInRange(memLevel, 1, 9, "memLevel");
this.contentSizeThreshold = ObjectUtil.checkPositiveOrZero(contentSizeThreshold, "contentSizeThreshold");
this.brotliOptions = null;
this.gzipOptions = null;
this.deflateOptions = null;
supportsCompressionOptions = false;
}
/**
* Create a new {@link HttpContentCompressor} Instance with specified
* {@link CompressionOptions}s and contentSizeThreshold set to {@code 0}
*
* @param compressionOptions {@link CompressionOptions} or {@code null} if the default
* should be used.
*/
public HttpContentCompressor(CompressionOptions... compressionOptions) {
this(0, compressionOptions);
}
/**
* Create a new {@link HttpContentCompressor} instance with specified
* {@link CompressionOptions}s
*
* @param contentSizeThreshold
* The response body is compressed when the size of the response
* body exceeds the threshold. The value should be a non negative
* number. {@code 0} will enable compression for all responses.
* @param compressionOptions {@link CompressionOptions} or {@code null}
* if the default should be used.
*/
public HttpContentCompressor(int contentSizeThreshold, CompressionOptions... compressionOptions) {
this.contentSizeThreshold = ObjectUtil.checkPositiveOrZero(contentSizeThreshold, "contentSizeThreshold");
BrotliOptions brotliOptions = null;
GzipOptions gzipOptions = null;
DeflateOptions deflateOptions = null;
if (compressionOptions == null || compressionOptions.length == 0) {
brotliOptions = StandardCompressionOptions.brotli();
gzipOptions = StandardCompressionOptions.gzip();
deflateOptions = StandardCompressionOptions.deflate();
} else {
ObjectUtil.deepCheckNotNull("compressionOptionsIterable", compressionOptions);
for (CompressionOptions compressionOption : compressionOptions) {
if (compressionOption instanceof BrotliOptions) {
brotliOptions = (BrotliOptions) compressionOption;
} else if (compressionOption instanceof GzipOptions) {
gzipOptions = (GzipOptions) compressionOption;
} else if (compressionOption instanceof DeflateOptions) {
deflateOptions = (DeflateOptions) compressionOption;
} else {
throw new IllegalArgumentException("Unsupported " + CompressionOptions.class.getSimpleName() +
": " + compressionOption);
}
}
if (brotliOptions == null) {
brotliOptions = StandardCompressionOptions.brotli();
}
if (gzipOptions == null) {
gzipOptions = StandardCompressionOptions.gzip();
}
if (deflateOptions == null) {
deflateOptions = StandardCompressionOptions.deflate();
}
}
this.brotliOptions = brotliOptions;
this.gzipOptions = gzipOptions;
this.deflateOptions = deflateOptions;
this.compressionLevel = -1;
this.windowBits = -1;
this.memLevel = -1;
supportsCompressionOptions = true;
}
@Override
@ -131,30 +214,109 @@ public class HttpContentCompressor extends HttpContentEncoder {
return null;
}
ZlibWrapper wrapper = determineWrapper(acceptEncoding);
if (wrapper == null) {
return null;
}
if (supportsCompressionOptions) {
String targetContentEncoding = determineEncoding(acceptEncoding);
if (targetContentEncoding == null) {
return null;
}
String targetContentEncoding;
switch (wrapper) {
case GZIP:
targetContentEncoding = "gzip";
break;
case ZLIB:
targetContentEncoding = "deflate";
break;
default:
if (targetContentEncoding.equals("gzip")) {
return new Result(targetContentEncoding,
new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(
ZlibWrapper.GZIP, gzipOptions.compressionLevel()
, gzipOptions.windowBits(), gzipOptions.memLevel())));
}
if (targetContentEncoding.equals("deflate")) {
return new Result(targetContentEncoding,
new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(
ZlibWrapper.ZLIB, deflateOptions.compressionLevel(),
deflateOptions.windowBits(), deflateOptions.memLevel())));
}
if (targetContentEncoding.equals("br")) {
return new Result(targetContentEncoding,
new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), new BrotliEncoder(brotliOptions.parameters())));
}
throw new Error();
}
} else {
ZlibWrapper wrapper = determineWrapper(acceptEncoding);
if (wrapper == null) {
return null;
}
return new Result(
targetContentEncoding,
new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(
wrapper, compressionLevel, windowBits, memLevel)));
String targetContentEncoding;
switch (wrapper) {
case GZIP:
targetContentEncoding = "gzip";
break;
case ZLIB:
targetContentEncoding = "deflate";
break;
default:
throw new Error();
}
return new Result(
targetContentEncoding,
new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(
wrapper, compressionLevel, windowBits, memLevel)));
}
}
@SuppressWarnings("FloatingPointEquality")
protected String determineEncoding(String acceptEncoding) {
float starQ = -1.0f;
float brQ = -1.0f;
float gzipQ = -1.0f;
float deflateQ = -1.0f;
for (String encoding : acceptEncoding.split(",")) {
float q = 1.0f;
int equalsPos = encoding.indexOf('=');
if (equalsPos != -1) {
try {
q = Float.parseFloat(encoding.substring(equalsPos + 1));
} catch (NumberFormatException e) {
// Ignore encoding
q = 0.0f;
}
}
if (encoding.contains("*")) {
starQ = q;
} else if (encoding.contains("br") && q > brQ) {
brQ = q;
} else if (encoding.contains("gzip") && q > gzipQ) {
gzipQ = q;
} else if (encoding.contains("deflate") && q > deflateQ) {
deflateQ = q;
}
}
if (brQ > 0.0f || gzipQ > 0.0f || deflateQ > 0.0f) {
if (brQ != -1.0f && brQ >= gzipQ) {
return Brotli.isAvailable() ? "br" : null;
} else if (gzipQ != -1.0f && gzipQ >= deflateQ) {
return "gzip";
} else if (deflateQ != -1.0f) {
return "deflate";
}
}
if (starQ > 0.0f) {
if (brQ == -1.0f) {
return Brotli.isAvailable() ? "br" : null;
}
if (gzipQ == -1.0f) {
return "gzip";
}
if (deflateQ == -1.0f) {
return "deflate";
}
}
return null;
}
@Deprecated
@SuppressWarnings("FloatingPointEquality")
protected ZlibWrapper determineWrapper(String acceptEncoding) {
float starQ = -1.0f;

87
codec-http/src/test/java/io/netty/handler/codec/http/BrotliContentCompressorTest.java Normal file
View File

@ -0,0 +1,87 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.http;
import io.netty.channel.embedded.EmbeddedChannel;
import org.junit.jupiter.api.Test;
import static org.hamcrest.CoreMatchers.instanceOf;
import static org.hamcrest.CoreMatchers.is;
import static org.hamcrest.CoreMatchers.not;
import static org.hamcrest.CoreMatchers.nullValue;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.jupiter.api.Assertions.*;
class BrotliContentCompressorTest {
@Test
void testGetTargetContentEncoding() {
HttpContentCompressor compressor = new HttpContentCompressor();
String[] tests = {
// Accept-Encoding -> Content-Encoding
"", null,
"*", "br",
"*;q=0.0", null,
"br", "br",
"compress, br;q=0.5", "br",
"br; q=0.5, identity", "br",
"br; q=0, deflate", "br",
};
for (int i = 0; i < tests.length; i += 2) {
String acceptEncoding = tests[i];
String contentEncoding = tests[i + 1];
String targetEncoding = compressor.determineEncoding(acceptEncoding);
assertEquals(contentEncoding, targetEncoding);
}
}
@Test
void testAcceptEncodingHttpRequest() {
EmbeddedChannel ch = new EmbeddedChannel(new HttpContentCompressor(null));
ch.writeInbound(newRequest());
FullHttpRequest fullHttpRequest = ch.readInbound();
fullHttpRequest.release();
HttpResponse res = new DefaultHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK);
res.headers().set(HttpHeaderNames.TRANSFER_ENCODING, HttpHeaderValues.CHUNKED);
ch.writeOutbound(res);
assertEncodedResponse(ch);
assertTrue(ch.close().isSuccess());
}
private static void assertEncodedResponse(EmbeddedChannel ch) {
Object o = ch.readOutbound();
assertThat(o, is(instanceOf(HttpResponse.class)));
assertEncodedResponse((HttpResponse) o);
}
private static void assertEncodedResponse(HttpResponse res) {
assertThat(res, is(not(instanceOf(HttpContent.class))));
assertThat(res.headers().get(HttpHeaderNames.TRANSFER_ENCODING), is("chunked"));
assertThat(res.headers().get(HttpHeaderNames.CONTENT_LENGTH), is(nullValue()));
assertThat(res.headers().get(HttpHeaderNames.CONTENT_ENCODING), is("br"));
}
private static FullHttpRequest newRequest() {
FullHttpRequest req = new DefaultFullHttpRequest(HttpVersion.HTTP_1_1, HttpMethod.GET, "/");
req.headers().set(HttpHeaderNames.ACCEPT_ENCODING, "br, gzip, deflate");
return req;
}
}

1
codec-http/src/test/java/io/netty/handler/codec/http/HttpContentCompressorTest.java
View File

@ -657,6 +657,7 @@ public class HttpContentCompressorTest {
assertThat(res.headers().get(HttpHeaderNames.CONTENT_LENGTH), is(nullValue()));
assertThat(res.headers().get(HttpHeaderNames.CONTENT_ENCODING), is("gzip"));
}
private static void assertAssembledEncodedResponse(EmbeddedChannel ch) {
Object o = ch.readOutbound();
assertThat(o, is(instanceOf(AssembledHttpResponse.class)));

5
codec-http2/pom.xml
View File

@ -88,6 +88,11 @@
<scope>test</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>com.aayushatharva.brotli4j</groupId>
<artifactId>brotli4j</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
</project>

96
codec-http2/src/main/java/io/netty/handler/codec/http2/CompressorHttp2ConnectionEncoder.java
View File

@ -21,14 +21,21 @@ import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.channel.embedded.EmbeddedChannel;
import io.netty.handler.codec.ByteToMessageDecoder;
import io.netty.handler.codec.compression.BrotliEncoder;
import io.netty.handler.codec.compression.ZlibCodecFactory;
import io.netty.handler.codec.compression.ZlibWrapper;
import io.netty.handler.codec.compression.BrotliOptions;
import io.netty.handler.codec.compression.CompressionOptions;
import io.netty.handler.codec.compression.DeflateOptions;
import io.netty.handler.codec.compression.GzipOptions;
import io.netty.handler.codec.compression.StandardCompressionOptions;
import io.netty.util.concurrent.PromiseCombiner;
import io.netty.util.internal.ObjectUtil;
import io.netty.util.internal.UnstableApi;
import static io.netty.handler.codec.http.HttpHeaderNames.CONTENT_ENCODING;
import static io.netty.handler.codec.http.HttpHeaderNames.CONTENT_LENGTH;
import static io.netty.handler.codec.http.HttpHeaderValues.BR;
import static io.netty.handler.codec.http.HttpHeaderValues.DEFLATE;
import static io.netty.handler.codec.http.HttpHeaderValues.GZIP;
import static io.netty.handler.codec.http.HttpHeaderValues.IDENTITY;
@ -41,19 +48,35 @@ import static io.netty.handler.codec.http.HttpHeaderValues.X_GZIP;
*/
@UnstableApi
public class CompressorHttp2ConnectionEncoder extends DecoratingHttp2ConnectionEncoder {
// We cannot remove this because it'll be breaking change
public static final int DEFAULT_COMPRESSION_LEVEL = 6;
public static final int DEFAULT_WINDOW_BITS = 15;
public static final int DEFAULT_MEM_LEVEL = 8;
private final int compressionLevel;
private final int windowBits;
private final int memLevel;
private int compressionLevel;
private int windowBits;
private int memLevel;
private final Http2Connection.PropertyKey propertyKey;
private final boolean supportsCompressionOptions;
private BrotliOptions brotliOptions;
private GzipOptions gzipCompressionOptions;
private DeflateOptions deflateOptions;
/**
* Create a new {@link CompressorHttp2ConnectionEncoder} instance
* with default implementation of {@link StandardCompressionOptions}
*/
public CompressorHttp2ConnectionEncoder(Http2ConnectionEncoder delegate) {
this(delegate, DEFAULT_COMPRESSION_LEVEL, DEFAULT_WINDOW_BITS, DEFAULT_MEM_LEVEL);
this(delegate, StandardCompressionOptions.brotli(), StandardCompressionOptions.gzip(),
StandardCompressionOptions.deflate());
}
/**
* Create a new {@link CompressorHttp2ConnectionEncoder} instance
*/
@Deprecated
public CompressorHttp2ConnectionEncoder(Http2ConnectionEncoder delegate, int compressionLevel, int windowBits,
int memLevel) {
super(delegate);
@ -71,6 +94,45 @@ public class CompressorHttp2ConnectionEncoder extends DecoratingHttp2ConnectionE
}
}
});
supportsCompressionOptions = false;
}
/**
* Create a new {@link CompressorHttp2ConnectionEncoder} with
* specified {@link StandardCompressionOptions}
*/
public CompressorHttp2ConnectionEncoder(Http2ConnectionEncoder delegate,
CompressionOptions... compressionOptionsArgs) {
super(delegate);
ObjectUtil.checkNotNull(compressionOptionsArgs, "CompressionOptions");
ObjectUtil.deepCheckNotNull("CompressionOptions", compressionOptionsArgs);
for (CompressionOptions compressionOptions : compressionOptionsArgs) {
if (compressionOptions instanceof BrotliOptions) {
brotliOptions = (BrotliOptions) compressionOptions;
} else if (compressionOptions instanceof GzipOptions) {
gzipCompressionOptions = (GzipOptions) compressionOptions;
} else if (compressionOptions instanceof DeflateOptions) {
deflateOptions = (DeflateOptions) compressionOptions;
} else {
throw new IllegalArgumentException("Unsupported " + CompressionOptions.class.getSimpleName() +
": " + compressionOptions);
}
}
supportsCompressionOptions = true;
propertyKey = connection().newKey();
connection().addListener(new Http2ConnectionAdapter() {
@Override
public void onStreamRemoved(Http2Stream stream) {
final EmbeddedChannel compressor = stream.getProperty(propertyKey);
if (compressor != null) {
cleanup(stream, compressor);
}
}
});
}
@Override
@ -190,6 +252,10 @@ public class CompressorHttp2ConnectionEncoder extends DecoratingHttp2ConnectionE
if (DEFLATE.contentEqualsIgnoreCase(contentEncoding) || X_DEFLATE.contentEqualsIgnoreCase(contentEncoding)) {
return newCompressionChannel(ctx, ZlibWrapper.ZLIB);
}
if (brotliOptions != null && BR.contentEqualsIgnoreCase(contentEncoding)) {
return new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), new BrotliEncoder(brotliOptions.parameters()));
}
// 'identity' or unsupported
return null;
}
@ -212,9 +278,25 @@ public class CompressorHttp2ConnectionEncoder extends DecoratingHttp2ConnectionE
* @param wrapper Defines what type of encoder should be used
*/
private EmbeddedChannel newCompressionChannel(final ChannelHandlerContext ctx, ZlibWrapper wrapper) {
return new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(wrapper, compressionLevel, windowBits,
memLevel));
if (supportsCompressionOptions) {
if (wrapper == ZlibWrapper.GZIP && gzipCompressionOptions != null) {
return new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(wrapper,
gzipCompressionOptions.compressionLevel(), gzipCompressionOptions.windowBits(),
gzipCompressionOptions.memLevel()));
} else if (wrapper == ZlibWrapper.ZLIB && deflateOptions != null) {
return new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(wrapper,
deflateOptions.compressionLevel(), deflateOptions.windowBits(),
deflateOptions.memLevel()));
} else {
throw new IllegalArgumentException("Unsupported ZlibWrapper: " + wrapper);
}
} else {
return new EmbeddedChannel(ctx.channel().id(), ctx.channel().metadata().hasDisconnect(),
ctx.channel().config(), ZlibCodecFactory.newZlibEncoder(wrapper, compressionLevel, windowBits,
memLevel));
}
}
/**

42
codec-http2/src/test/java/io/netty/handler/codec/http2/DataCompressionHttp2Test.java
View File

@ -215,6 +215,48 @@ public class DataCompressionHttp2Test {
}
}
@Test
public void brotliEncodingSingleEmptyMessage() throws Exception {
final String text = "";
final ByteBuf data = Unpooled.copiedBuffer(text.getBytes());
bootstrapEnv(data.readableBytes());
try {
final Http2Headers headers = new DefaultHttp2Headers().method(POST).path(PATH)
.set(HttpHeaderNames.CONTENT_ENCODING, HttpHeaderValues.BR);
runInChannel(clientChannel, () -> {
clientEncoder.writeHeaders(ctxClient(), 3, headers, 0, false, newPromiseClient());
clientEncoder.writeData(ctxClient(), 3, data.retain(), 0, true, newPromiseClient());
clientHandler.flush(ctxClient());
});
awaitServer();
assertEquals(text, serverOut.toString(CharsetUtil.UTF_8.name()));
} finally {
data.release();
}
}
@Test
public void brotliEncodingSingleMessage() throws Exception {
final String text = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaabbbbbbbbbbbbbbbbbbbbbbbbbbbbbccccccccccccccccccccccc";
final ByteBuf data = Unpooled.copiedBuffer(text.getBytes(CharsetUtil.UTF_8.name()));
bootstrapEnv(data.readableBytes());
try {
final Http2Headers headers = new DefaultHttp2Headers().method(POST).path(PATH)
.set(HttpHeaderNames.CONTENT_ENCODING, HttpHeaderValues.BR);
runInChannel(clientChannel, () -> {
clientEncoder.writeHeaders(ctxClient(), 3, headers, 0, false, newPromiseClient());
clientEncoder.writeData(ctxClient(), 3, data.retain(), 0, true, newPromiseClient());
clientHandler.flush(ctxClient());
});
awaitServer();
assertEquals(text, serverOut.toString(CharsetUtil.UTF_8.name()));
} finally {
data.release();
}
}
@Test
public void deflateEncodingWriteLargeMessage() throws Exception {
final int BUFFER_SIZE = 1 << 12;

10
codec/src/main/java/io/netty/handler/codec/compression/Brotli.java
View File

@ -25,6 +25,7 @@ public final class Brotli {
private static final InternalLogger logger = InternalLoggerFactory.getInstance(Brotli.class);
private static final ClassNotFoundException CNFE;
private static Throwable cause;
static {
ClassNotFoundException cnfe = null;
@ -42,7 +43,7 @@ public final class Brotli {
// If in the classpath, try to load the native library and initialize brotli4j.
if (cnfe == null) {
Throwable cause = Brotli4jLoader.getUnavailabilityCause();
cause = Brotli4jLoader.getUnavailabilityCause();
if (cause != null) {
logger.debug("Failed to load brotli4j; Brotli support will be unavailable.", cause);
}
@ -70,6 +71,13 @@ public final class Brotli {
Brotli4jLoader.ensureAvailability();
}
/**
* Returns {@link Throwable} of unavailability cause
*/
public static Throwable cause() {
return cause;
}
private Brotli() {
}
}

92
codec/src/main/java/io/netty/handler/codec/compression/BrotliEncoder.java Normal file
View File

@ -0,0 +1,92 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
import com.aayushatharva.brotli4j.encoder.Encoder;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToByteEncoder;
import io.netty.util.ReferenceCountUtil;
import io.netty.util.internal.ObjectUtil;
/**
* Compress a {@link ByteBuf} with the brotli format.
*
* See <a href="https://github.com/google/brotli">brotli</a>.
*/
@ChannelHandler.Sharable
public final class BrotliEncoder extends MessageToByteEncoder<ByteBuf> {
private final Encoder.Parameters parameters;
/**
* Create a new {@link BrotliEncoder} Instance
* with {@link Encoder.Parameters#setQuality(int)} set to 4
* and {@link Encoder.Parameters#setMode(Encoder.Mode)} set to {@link Encoder.Mode#TEXT}
*/
public BrotliEncoder() {
this(BrotliOptions.DEFAULT);
}
/**
* Create a new {@link BrotliEncoder} Instance
*
* @param parameters {@link Encoder.Parameters} Instance
*/
public BrotliEncoder(Encoder.Parameters parameters) {
this.parameters = ObjectUtil.checkNotNull(parameters, "Parameters");
}
/**
* Create a new {@link BrotliEncoder} Instance
*
* @param brotliOptions {@link BrotliOptions} to use.
*/
public BrotliEncoder(BrotliOptions brotliOptions) {
this(brotliOptions.parameters());
}
@Override
protected void encode(ChannelHandlerContext ctx, ByteBuf msg, ByteBuf out) throws Exception {
// NO-OP
}
@Override
protected ByteBuf allocateBuffer(ChannelHandlerContext ctx, ByteBuf msg, boolean preferDirect) throws Exception {
// If ByteBuf is unreadable, then return EMPTY_BUFFER.
if (!msg.isReadable()) {
return Unpooled.EMPTY_BUFFER;
}
try {
byte[] uncompressed = ByteBufUtil.getBytes(msg, msg.readerIndex(), msg.readableBytes(), false);
byte[] compressed = Encoder.compress(uncompressed, parameters);
if (preferDirect) {
ByteBuf out = ctx.alloc().ioBuffer(compressed.length);
out.writeBytes(compressed);
return out;
} else {
return Unpooled.wrappedBuffer(compressed);
}
} catch (Exception e) {
ReferenceCountUtil.release(msg);
throw e;
}
}
}

54
codec/src/main/java/io/netty/handler/codec/compression/BrotliOptions.java Normal file
View File

@ -0,0 +1,54 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
import com.aayushatharva.brotli4j.encoder.Encoder;
import io.netty.util.internal.ObjectUtil;
/**
* {@link BrotliOptions} holds {@link Encoder.Parameters} for
* Brotli compression.
*/
public final class BrotliOptions implements CompressionOptions {
private final Encoder.Parameters parameters;
/**
* Default implementation of {@link BrotliOptions} with{@link Encoder.Parameters#setQuality(int)} set to 4
* and {@link Encoder.Parameters#setMode(Encoder.Mode)} set to {@link Encoder.Mode#TEXT}
*/
static final BrotliOptions DEFAULT = new BrotliOptions(
new Encoder.Parameters().setQuality(4).setMode(Encoder.Mode.TEXT)
);
/**
* Create a new {@link BrotliOptions}
*
* @param parameters {@link Encoder.Parameters} Instance
* @throws NullPointerException If {@link Encoder.Parameters} is {@code null}
*/
BrotliOptions(Encoder.Parameters parameters) {
this.parameters = ObjectUtil.checkNotNull(parameters, "Parameters");
if (!Brotli.isAvailable()) {
throw new IllegalStateException("Brotli is not available", Brotli.cause());
}
}
public Encoder.Parameters parameters() {
return parameters;
}
}

27
codec/src/main/java/io/netty/handler/codec/compression/CompressionOptions.java Normal file
View File

@ -0,0 +1,27 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
/**
* {@link CompressionOptions} provides compression options for
* various types of compressor types, like Brotli.
*
* A {@link CompressionOptions} instance is thread-safe
* and should be shared between multiple instances of Compressor.
*/
public interface CompressionOptions {
// Empty
}

73
codec/src/main/java/io/netty/handler/codec/compression/DeflateOptions.java Normal file
View File

@ -0,0 +1,73 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
import io.netty.util.internal.ObjectUtil;
/**
* {@link DeflateOptions} holds {@link #compressionLevel()},
* {@link #memLevel()} and {@link #windowBits()} for Deflate compression.
*/
public class DeflateOptions implements CompressionOptions {
private final int compressionLevel;
private final int windowBits;
private final int memLevel;
/**
* Default implementation of {@link DeflateOptions} with
* {@link #compressionLevel} set to 6, {@link #windowBits} set to 15
* and {@link #memLevel} set to 8.
*/
static final DeflateOptions DEFAULT = new DeflateOptions(
6, 15, 8
);
/**
* Create a new {@link DeflateOptions} Instance
*
* @param compressionLevel {@code 1} yields the fastest compression and {@code 9} yields the
* best compression. {@code 0} means no compression. The default
* compression level is {@code 6}.
*
* @param windowBits The base two logarithm of the size of the history buffer. The
* value should be in the range {@code 9} to {@code 15} inclusive.
* Larger values result in better compression at the expense of
* memory usage. The default value is {@code 15}.
*
* @param memLevel How much memory should be allocated for the internal compression
* state. {@code 1} uses minimum memory and {@code 9} uses maximum
* memory. Larger values result in better and faster compression
* at the expense of memory usage. The default value is {@code 8}
*/
DeflateOptions(int compressionLevel, int windowBits, int memLevel) {
this.compressionLevel = ObjectUtil.checkInRange(compressionLevel, 0, 9, "compressionLevel");
this.windowBits = ObjectUtil.checkInRange(windowBits, 9, 15, "windowBits");
this.memLevel = ObjectUtil.checkInRange(memLevel, 1, 9, "memLevel");
}
public int compressionLevel() {
return compressionLevel;
}
public int windowBits() {
return windowBits;
}
public int memLevel() {
return memLevel;
}
}

54
codec/src/main/java/io/netty/handler/codec/compression/GzipOptions.java Normal file
View File

@ -0,0 +1,54 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
/**
* {@link GzipOptions} holds {@link #compressionLevel()},
* {@link #memLevel()} and {@link #windowBits()} for Gzip compression.
* This class is an extension of {@link DeflateOptions}
*/
public final class GzipOptions extends DeflateOptions {
/**
* Default implementation of {@link GzipOptions} with
* {@link #compressionLevel()} set to 6, {@link #windowBits()} set to 15
* and {@link #memLevel()} set to 8.
*/
static final GzipOptions DEFAULT = new GzipOptions(
6, 15, 8
);
/**
* Create a new {@link GzipOptions} Instance
*
* @param compressionLevel {@code 1} yields the fastest compression and {@code 9} yields the
* best compression. {@code 0} means no compression. The default
* compression level is {@code 6}.
*
* @param windowBits The base two logarithm of the size of the history buffer. The
* value should be in the range {@code 9} to {@code 15} inclusive.
* Larger values result in better compression at the expense of
* memory usage. The default value is {@code 15}.
*
* @param memLevel How much memory should be allocated for the internal compression
* state. {@code 1} uses minimum memory and {@code 9} uses maximum
* memory. Larger values result in better and faster compression
* at the expense of memory usage. The default value is {@code 8}
*/
GzipOptions(int compressionLevel, int windowBits, int memLevel) {
super(compressionLevel, windowBits, memLevel);
}
}

71
codec/src/main/java/io/netty/handler/codec/compression/StandardCompressionOptions.java Normal file
View File

@ -0,0 +1,71 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
import com.aayushatharva.brotli4j.encoder.Encoder;
/**
* Standard Compression Options for {@link BrotliOptions},
* {@link GzipOptions} and {@link DeflateOptions}
*/
public final class StandardCompressionOptions {
private StandardCompressionOptions() {
// Prevent outside initialization
}
/**
* @see BrotliOptions#DEFAULT
*/
public static BrotliOptions brotli() {
return BrotliOptions.DEFAULT;
}
/**
* @see BrotliOptions#BrotliOptions(Encoder.Parameters)
*/
public static BrotliOptions brotli(Encoder.Parameters parameters) {
return new BrotliOptions(parameters);
}
/**
* @see GzipOptions#DEFAULT
*/
public static GzipOptions gzip() {
return GzipOptions.DEFAULT;
}
/**
* @see GzipOptions#GzipOptions(int, int, int)
*/
public static GzipOptions gzip(int compressionLevel, int windowBits, int memLevel) {
return new GzipOptions(compressionLevel, windowBits, memLevel);
}
/**
* @see DeflateOptions#DEFAULT
*/
public static DeflateOptions deflate() {
return DeflateOptions.DEFAULT;
}
/**
* @see DeflateOptions#DeflateOptions(int, int, int)
*/
public static DeflateOptions deflate(int compressionLevel, int windowBits, int memLevel) {
return new DeflateOptions(compressionLevel, windowBits, memLevel);
}
}

4
codec/src/test/java/io/netty/handler/codec/compression/BrotliDecoderTest.java
View File

@ -136,7 +136,7 @@ public class BrotliDecoderTest {
decompressed.release();
}
private void testDecompressionOfBatchedFlow(final ByteBuf expected, final ByteBuf data) {
private void testDecompressionOfBatchedFlow(final ByteBuf expected, final ByteBuf data) {
final int compressedLength = data.readableBytes();
int written = 0, length = RANDOM.nextInt(100);
while (written + length < compressedLength) {
@ -155,7 +155,7 @@ public class BrotliDecoderTest {
data.release();
}
private static ByteBuf readDecompressed(final EmbeddedChannel channel) {
private static ByteBuf readDecompressed(final EmbeddedChannel channel) {
CompositeByteBuf decompressed = Unpooled.compositeBuffer();
ByteBuf msg;
while ((msg = channel.readInbound()) != null) {

77
codec/src/test/java/io/netty/handler/codec/compression/BrotliEncoderTest.java Normal file
View File

@ -0,0 +1,77 @@
/*
* Copyright 2021 The Netty Project
*
* The Netty Project 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:
*
* https://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 io.netty.handler.codec.compression;
import com.aayushatharva.brotli4j.decoder.Decoder;
import com.aayushatharva.brotli4j.decoder.DecoderJNI;
import com.aayushatharva.brotli4j.decoder.DirectDecompress;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.CompositeByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.embedded.EmbeddedChannel;
import io.netty.util.internal.PlatformDependent;
import org.junit.jupiter.api.condition.DisabledIf;
@DisabledIf(value = "isNotSupported", disabledReason = "Brotli is not supported on this platform")
public class BrotliEncoderTest extends AbstractEncoderTest {
static {
try {
Brotli.ensureAvailability();
} catch (Throwable throwable) {
throw new ExceptionInInitializerError(throwable);
}
}
@Override
public EmbeddedChannel createChannel() {
return new EmbeddedChannel(new BrotliEncoder());
}
@Override
protected ByteBuf decompress(ByteBuf compressed, int originalLength) throws Exception {
byte[] compressedArray = new byte[compressed.readableBytes()];
compressed.readBytes(compressedArray);
compressed.release();
DirectDecompress decompress = Decoder.decompress(compressedArray);
if (decompress.getResultStatus() == DecoderJNI.Status.ERROR) {
throw new DecompressionException("Brotli stream corrupted");
}
byte[] decompressed = decompress.getDecompressedData();
return Unpooled.wrappedBuffer(decompressed);
}
@Override
protected ByteBuf readDecompressed(final int dataLength) throws Exception {
CompositeByteBuf decompressed = Unpooled.compositeBuffer();
ByteBuf msg;
while ((msg = channel.readOutbound()) != null) {
if (msg.isReadable()) {
decompressed.addComponent(true, decompress(msg, -1));
} else {
msg.release();
}
}
return decompressed;
}
static boolean isNotSupported() {
return (PlatformDependent.isOsx() || PlatformDependent.isWindows())
&& "aarch_64".equals(PlatformDependent.normalizedArch());
}
}

20
common/src/main/java/io/netty/util/internal/ObjectUtil.java
View File

@ -42,6 +42,26 @@ public final class ObjectUtil {
return Objects.requireNonNull(arg, text);
}
/**
* Check that the given varargs is not null and does not contain elements
* null elements.
*
* If it is, throws {@link NullPointerException}.
* Otherwise, returns the argument.
*/
public static <T> T[] deepCheckNotNull(String text, T... varargs) {
if (varargs == null) {
throw new NullPointerException(text);
}
for (T element : varargs) {
if (element == null) {
throw new NullPointerException(text);
}
}
return varargs;
}
/**
* Checks that the given argument is not null. If it is, throws {@link IllegalArgumentException}.
* Otherwise, returns the argument.

201
license/LICENSE.brotli4j.txt Normal file
View File

@ -0,0 +1,201 @@
Apache License
Version 2.0, January 2004
https://www.apache.org/licenses/
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
1. Definitions.
"License" shall mean the terms and conditions for use, reproduction,
and distribution as defined by Sections 1 through 9 of this document.
"Licensor" shall mean the copyright owner or entity authorized by
the copyright owner that is granting the License.
"Legal Entity" shall mean the union of the acting entity and all
other entities that control, are controlled by, or are under common
control with that entity. For the purposes of this definition,
"control" means (i) the power, direct or indirect, to cause the
direction or management of such entity, whether by contract or
otherwise, or (ii) ownership of fifty percent (50%) or more of the
outstanding shares, or (iii) beneficial ownership of such entity.
"You" (or "Your") shall mean an individual or Legal Entity
exercising permissions granted by this License.
"Source" form shall mean the preferred form for making modifications,
including but not limited to software source code, documentation
source, and configuration files.
"Object" form shall mean any form resulting from mechanical
transformation or translation of a Source form, including but
not limited to compiled object code, generated documentation,
and conversions to other media types.
"Work" shall mean the work of authorship, whether in Source or
Object form, made available under the License, as indicated by a
copyright notice that is included in or attached to the work
(an example is provided in the Appendix below).
"Derivative Works" shall mean any work, whether in Source or Object
form, that is based on (or derived from) the Work and for which the
editorial revisions, annotations, elaborations, or other modifications
represent, as a whole, an original work of authorship. For the purposes
of this License, Derivative Works shall not include works that remain
separable from, or merely link (or bind by name) to the interfaces of,
the Work and Derivative Works thereof.
"Contribution" shall mean any work of authorship, including
the original version of the Work and any modifications or additions
to that Work or Derivative Works thereof, that is intentionally
submitted to Licensor for inclusion in the Work by the copyright owner
or by an individual or Legal Entity authorized to submit on behalf of
the copyright owner. For the purposes of this definition, "submitted"
means any form of electronic, verbal, or written communication sent
to the Licensor or its representatives, including but not limited to
communication on electronic mailing lists, source code control systems,
and issue tracking systems that are managed by, or on behalf of, the
Licensor for the purpose of discussing and improving the Work, but
excluding communication that is conspicuously marked or otherwise
designated in writing by the copyright owner as "Not a Contribution."
"Contributor" shall mean Licensor and any individual or Legal Entity
on behalf of whom a Contribution has been received by Licensor and
subsequently incorporated within the Work.
2. Grant of Copyright License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
copyright license to reproduce, prepare Derivative Works of,
publicly display, publicly perform, sublicense, and distribute the
Work and such Derivative Works in Source or Object form.
3. Grant of Patent License. Subject to the terms and conditions of
this License, each Contributor hereby grants to You a perpetual,
worldwide, non-exclusive, no-charge, royalty-free, irrevocable
(except as stated in this section) patent license to make, have made,
use, offer to sell, sell, import, and otherwise transfer the Work,
where such license applies only to those patent claims licensable
by such Contributor that are necessarily infringed by their
Contribution(s) alone or by combination of their Contribution(s)
with the Work to which such Contribution(s) was submitted. If You
institute patent litigation against any entity (including a
cross-claim or counterclaim in a lawsuit) alleging that the Work
or a Contribution incorporated within the Work constitutes direct
or contributory patent infringement, then any patent licenses
granted to You under this License for that Work shall terminate
as of the date such litigation is filed.
4. Redistribution. You may reproduce and distribute copies of the
Work or Derivative Works thereof in any medium, with or without
modifications, and in Source or Object form, provided that You
meet the following conditions:
(a) You must give any other recipients of the Work or
Derivative Works a copy of this License; and
(b) You must cause any modified files to carry prominent notices
stating that You changed the files; and
(c) You must retain, in the Source form of any Derivative Works
that You distribute, all copyright, patent, trademark, and
attribution notices from the Source form of the Work,
excluding those notices that do not pertain to any part of
the Derivative Works; and
(d) If the Work includes a "NOTICE" text file as part of its
distribution, then any Derivative Works that You distribute must
include a readable copy of the attribution notices contained
within such NOTICE file, excluding those notices that do not
pertain to any part of the Derivative Works, in at least one
of the following places: within a NOTICE text file distributed
as part of the Derivative Works; within the Source form or
documentation, if provided along with the Derivative Works; or,
within a display generated by the Derivative Works, if and
wherever such third-party notices normally appear. The contents
of the NOTICE file are for informational purposes only and
do not modify the License. You may add Your own attribution
notices within Derivative Works that You distribute, alongside
or as an addendum to the NOTICE text from the Work, provided
that such additional attribution notices cannot be construed
as modifying the License.
You may add Your own copyright statement to Your modifications and
may provide additional or different license terms and conditions
for use, reproduction, or distribution of Your modifications, or
for any such Derivative Works as a whole, provided Your use,
reproduction, and distribution of the Work otherwise complies with
the conditions stated in this License.
5. Submission of Contributions. Unless You explicitly state otherwise,
any Contribution intentionally submitted for inclusion in the Work
by You to the Licensor shall be under the terms and conditions of
this License, without any additional terms or conditions.
Notwithstanding the above, nothing herein shall supersede or modify
the terms of any separate license agreement you may have executed
with Licensor regarding such Contributions.
6. Trademarks. This License does not grant permission to use the trade
names, trademarks, service marks, or product names of the Licensor,
except as required for reasonable and customary use in describing the
origin of the Work and reproducing the content of the NOTICE file.
7. Disclaimer of Warranty. Unless required by applicable law or
agreed to in writing, Licensor provides the Work (and each
Contributor provides its Contributions) on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied, including, without limitation, any warranties or conditions
of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
PARTICULAR PURPOSE. You are solely responsible for determining the
appropriateness of using or redistributing the Work and assume any
risks associated with Your exercise of permissions under this License.
8. Limitation of Liability. In no event and under no legal theory,
whether in tort (including negligence), contract, or otherwise,
unless required by applicable law (such as deliberate and grossly
negligent acts) or agreed to in writing, shall any Contributor be
liable to You for damages, including any direct, indirect, special,
incidental, or consequential damages of any character arising as a
result of this License or out of the use or inability to use the
Work (including but not limited to damages for loss of goodwill,
work stoppage, computer failure or malfunction, or any and all
other commercial damages or losses), even if such Contributor
has been advised of the possibility of such damages.
9. Accepting Warranty or Additional Liability. While redistributing
the Work or Derivative Works thereof, You may choose to offer,
and charge a fee for, acceptance of support, warranty, indemnity,
or other liability obligations and/or rights consistent with this
License. However, in accepting such obligations, You may act only
on Your own behalf and on Your sole responsibility, not on behalf
of any other Contributor, and only if You agree to indemnify,
defend, and hold each Contributor harmless for any liability
incurred by, or claims asserted against, such Contributor by reason
of your accepting any such warranty or additional liability.
END OF TERMS AND CONDITIONS
APPENDIX: How to apply the Apache License to your work.
To apply the Apache License to your work, attach the following
boilerplate notice, with the fields enclosed by brackets "[]"
replaced with your own identifying information. (Don't include
the brackets!) The text should be enclosed in the appropriate
comment syntax for the file format. We also recommend that a
file or class name and description of purpose be included on the
same "printed page" as the copyright notice for easier
identification within third-party archives.
Copyright [yyyy] [name of copyright owner]
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
https://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.