/*
* Copyright 2014 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:
*
* 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 io.netty.handler.codec.http;
import io.netty.buffer.ByteBuf;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public final class HttpHeaderUtil {
/**
* Returns {@code true} if and only if the connection can remain open and
* thus 'kept alive'. This methods respects the value of the
* {@code "Connection"} header first and then the return value of
* {@link HttpVersion#isKeepAliveDefault()}.
*/
public static boolean isKeepAlive(HttpMessage message) {
CharSequence connection = message.headers().get(HttpHeaderNames.CONNECTION);
if (connection != null && HttpHeaderValues.CLOSE.equalsIgnoreCase(connection)) {
return false;
}
if (message.protocolVersion().isKeepAliveDefault()) {
return !HttpHeaderValues.CLOSE.equalsIgnoreCase(connection);
} else {
return HttpHeaderValues.KEEP_ALIVE.equalsIgnoreCase(connection);
}
}
/**
* Sets the value of the {@code "Connection"} header depending on the
* protocol version of the specified message. This getMethod sets or removes
* the {@code "Connection"} header depending on what the default keep alive
* mode of the message's protocol version is, as specified by
* {@link HttpVersion#isKeepAliveDefault()}.
*
* - If the connection is kept alive by default:
*
* - set to {@code "close"} if {@code keepAlive} is {@code false}.
* - remove otherwise.
*
* - If the connection is closed by default:
*
* - set to {@code "keep-alive"} if {@code keepAlive} is {@code true}.
* - remove otherwise.
*
*
*/
public static void setKeepAlive(HttpMessage message, boolean keepAlive) {
HttpHeaders h = message.headers();
if (message.protocolVersion().isKeepAliveDefault()) {
if (keepAlive) {
h.remove(HttpHeaderNames.CONNECTION);
} else {
h.set(HttpHeaderNames.CONNECTION, HttpHeaderValues.CLOSE);
}
} else {
if (keepAlive) {
h.set(HttpHeaderNames.CONNECTION, HttpHeaderValues.KEEP_ALIVE);
} else {
h.remove(HttpHeaderNames.CONNECTION);
}
}
}
/**
* Returns the length of the content. Please note that this value is
* not retrieved from {@link HttpContent#content()} but from the
* {@code "Content-Length"} header, and thus they are independent from each
* other.
*
* @return the content length
*
* @throws NumberFormatException
* if the message does not have the {@code "Content-Length"} header
* or its value is not a number
*/
public static long getContentLength(HttpMessage message) {
String value = message.headers().get(HttpHeaderNames.CONTENT_LENGTH);
if (value != null) {
return Long.parseLong(value);
}
// We know the content length if it's a Web Socket message even if
// Content-Length header is missing.
long webSocketContentLength = getWebSocketContentLength(message);
if (webSocketContentLength >= 0) {
return webSocketContentLength;
}
// Otherwise we don't.
throw new NumberFormatException("header not found: " + HttpHeaderNames.CONTENT_LENGTH);
}
/**
* Returns the length of the content. Please note that this value is
* not retrieved from {@link HttpContent#content()} but from the
* {@code "Content-Length"} header, and thus they are independent from each
* other.
*
* @return the content length or {@code defaultValue} if this message does
* not have the {@code "Content-Length"} header or its value is not
* a number
*/
public static long getContentLength(HttpMessage message, long defaultValue) {
String value = message.headers().get(HttpHeaderNames.CONTENT_LENGTH);
if (value != null) {
return Long.parseLong(value);
}
// We know the content length if it's a Web Socket message even if
// Content-Length header is missing.
long webSocketContentLength = getWebSocketContentLength(message);
if (webSocketContentLength >= 0) {
return webSocketContentLength;
}
// Otherwise we don't.
return defaultValue;
}
/**
* Returns the content length of the specified web socket message. If the
* specified message is not a web socket message, {@code -1} is returned.
*/
private static int getWebSocketContentLength(HttpMessage message) {
// WebSockset messages have constant content-lengths.
HttpHeaders h = message.headers();
if (message instanceof HttpRequest) {
HttpRequest req = (HttpRequest) message;
if (HttpMethod.GET.equals(req.method()) &&
h.contains(HttpHeaderNames.SEC_WEBSOCKET_KEY1) &&
h.contains(HttpHeaderNames.SEC_WEBSOCKET_KEY2)) {
return 8;
}
} else if (message instanceof HttpResponse) {
HttpResponse res = (HttpResponse) message;
if (res.status().code() == 101 &&
h.contains(HttpHeaderNames.SEC_WEBSOCKET_ORIGIN) &&
h.contains(HttpHeaderNames.SEC_WEBSOCKET_LOCATION)) {
return 16;
}
}
// Not a web socket message
return -1;
}
/**
* Sets the {@code "Content-Length"} header.
*/
public static void setContentLength(HttpMessage message, long length) {
message.headers().set(HttpHeaderNames.CONTENT_LENGTH, length);
}
public static boolean isContentLengthSet(HttpMessage m) {
return m.headers().contains(HttpHeaderNames.CONTENT_LENGTH);
}
/**
* Returns {@code true} if and only if the specified message contains the
* {@code "Expect: 100-continue"} header.
*/
public static boolean is100ContinueExpected(HttpMessage message) {
// Expect: 100-continue is for requests only.
if (!(message instanceof HttpRequest)) {
return false;
}
// It works only on HTTP/1.1 or later.
if (message.protocolVersion().compareTo(HttpVersion.HTTP_1_1) < 0) {
return false;
}
// In most cases, there will be one or zero 'Expect' header.
CharSequence value = message.headers().get(HttpHeaderNames.EXPECT);
if (value == null) {
return false;
}
if (HttpHeaderValues.CONTINUE.equalsIgnoreCase(value)) {
return true;
}
// Multiple 'Expect' headers. Search through them.
return message.headers().contains(HttpHeaderNames.EXPECT, HttpHeaderValues.CONTINUE, true);
}
/**
* Sets or removes the {@code "Expect: 100-continue"} header to / from the
* specified message. If the specified {@code value} is {@code true},
* the {@code "Expect: 100-continue"} header is set and all other previous
* {@code "Expect"} headers are removed. Otherwise, all {@code "Expect"}
* headers are removed completely.
*/
public static void set100ContinueExpected(HttpMessage message, boolean expected) {
if (expected) {
message.headers().set(HttpHeaderNames.EXPECT, HttpHeaderValues.CONTINUE);
} else {
message.headers().remove(HttpHeaderNames.EXPECT);
}
}
/**
* Checks to see if the transfer encoding in a specified {@link HttpMessage} is chunked
*
* @param message The message to check
* @return True if transfer encoding is chunked, otherwise false
*/
public static boolean isTransferEncodingChunked(HttpMessage message) {
return message.headers().contains(HttpHeaderNames.TRANSFER_ENCODING, HttpHeaderValues.CHUNKED, true);
}
public static void setTransferEncodingChunked(HttpMessage m, boolean chunked) {
if (chunked) {
m.headers().add(HttpHeaderNames.TRANSFER_ENCODING, HttpHeaderValues.CHUNKED);
m.headers().remove(HttpHeaderNames.CONTENT_LENGTH);
} else {
// Make a copy to be able to modify values while iterating
List encodings = m.headers().getAll(HttpHeaderNames.TRANSFER_ENCODING);
if (encodings.isEmpty()) {
return;
}
List values = new ArrayList(encodings);
Iterator valuesIt = values.iterator();
while (valuesIt.hasNext()) {
CharSequence value = valuesIt.next();
if (HttpHeaderValues.CHUNKED.equalsIgnoreCase(value)) {
valuesIt.remove();
}
}
if (values.isEmpty()) {
m.headers().remove(HttpHeaderNames.TRANSFER_ENCODING);
} else {
m.headers().set(HttpHeaderNames.TRANSFER_ENCODING, values);
}
}
}
static void encodeAscii0(CharSequence seq, ByteBuf buf) {
int length = seq.length();
for (int i = 0 ; i < length; i++) {
buf.writeByte(c2b(seq.charAt(i)));
}
}
private static byte c2b(char c) {
if (c > 255) {
return '?';
}
return (byte) c;
}
private HttpHeaderUtil() { }
}