netflix.karyon.transport.http.HttpKeyEvaluationContext Maven / Gradle / Ivy
package netflix.karyon.transport.http;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.HttpRequest;
import io.netty.util.Attribute;
import io.netty.util.AttributeKey;
import io.reactivex.netty.protocol.http.server.HttpServerRequest;
import netflix.karyon.transport.interceptor.KeyEvaluationContext;
/**
* @author Nitesh Kant
*/
public class HttpKeyEvaluationContext extends KeyEvaluationContext {
/**
* In order to optimize for request URI parsing, karyon stores the {@link QueryStringDecoder} instances, if created,
* in the {@link io.netty.channel.ChannelHandlerContext} as an {@link io.netty.util.Attribute}.
* This attribute is not always available and hence the users must always check for availability. It is always a
* good practice to store the decoder back in the context, once created so that other code can use it if required.
*/
public static final AttributeKey queryDecoderKey = AttributeKey.valueOf("_queryStringDecoder");
private QueryStringDecoder queryStringDecoder;
public HttpKeyEvaluationContext(Channel channel) {
super(channel);
channel.attr(queryDecoderKey).remove();
}
/**
* Parses (if not done previously) and returns the path component in the URI.
*
* @param httpRequest HTTP request for which the URI path is to be returned.
*
* @return The path component of the URI (as returned by {@link HttpRequest#getUri()} or {@code null} if the
* URI is null.
*/
String getRequestUriPath(HttpServerRequest httpRequest) {
String uri = httpRequest.getUri();
if (null == uri) {
return null;
}
if (null == queryStringDecoder) {
if (null == channel) {
queryStringDecoder = new QueryStringDecoder(uri);
} else {
queryStringDecoder = getOrCreateQueryStringDecoder(httpRequest);
}
}
return queryStringDecoder.nettyDecoder().path();
}
private QueryStringDecoder getOrCreateQueryStringDecoder(HttpServerRequest request) {
if (null == request) {
throw new NullPointerException("Request can not be null.");
}
String uri = request.getUri();
if (null == uri) {
return null;
}
Attribute queryDecoderAttr = channel.attr(queryDecoderKey);
QueryStringDecoder _queryStringDecoder = queryDecoderAttr.get();
if (null == _queryStringDecoder) {
_queryStringDecoder = new QueryStringDecoder(uri);
queryDecoderAttr.setIfAbsent(_queryStringDecoder);
}
return _queryStringDecoder;
}
public static QueryStringDecoder getOrCreateQueryStringDecoder(HttpServerRequest request,
ChannelHandlerContext channelHandlerContext) {
if (null == request) {
throw new NullPointerException("Request can not be null.");
}
String uri = request.getUri();
if (null == uri) {
return null;
}
Attribute queryDecoderAttr = channelHandlerContext.attr(queryDecoderKey);
QueryStringDecoder _queryStringDecoder = queryDecoderAttr.get();
if (null == _queryStringDecoder) {
_queryStringDecoder = new QueryStringDecoder(uri);
queryDecoderAttr.setIfAbsent(_queryStringDecoder);
}
return _queryStringDecoder;
}
}