src/main/java/org/takes/facets/fork/FkEncoding.java
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2024 Yegor Bugayenko
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.takes.facets.fork;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.regex.Pattern;
import lombok.EqualsAndHashCode;
import org.cactoos.text.Lowered;
import org.cactoos.text.TextOf;
import org.cactoos.text.Trimmed;
import org.cactoos.text.UncheckedText;
import org.takes.Request;
import org.takes.Response;
import org.takes.misc.Opt;
import org.takes.rq.RqHeaders;
/**
* Fork by encoding accepted by "Accept-Encoding" HTTP header.
*
* <p>Use this fork in order to deliver responses with different
* encoding, depending on user preferences. For example, you want
* to deliver GZIP-compressed response when "Accept-Encoding" request
* header contains "gzip". Here is how:
*
* <pre> new TkFork(
* new FkEncoding("gzip", new RsGzip(response)),
* new FkEncoding("", response)
* )</pre>
*
* <p>Empty string as an encoding means that the fork should match
* in any case.
*
* <p>The class is immutable and thread-safe.
* @see org.takes.facets.fork.RsFork
* @since 0.10
*/
@EqualsAndHashCode
public final class FkEncoding implements Fork {
/**
* Accept-Encoding separator.
*/
private static final Pattern ENCODING_SEP = Pattern.compile("\\s*,\\s*");
/**
* Encoding we can deliver (or empty string).
*/
private final String encoding;
/**
* Response to return.
*/
private final Response origin;
/**
* Ctor.
* @param enc Encoding we accept
* @param response Response to return
*/
public FkEncoding(final String enc, final Response response) {
this.encoding = new UncheckedText(
new Lowered(new Trimmed(new TextOf(enc)))
).asString();
this.origin = response;
}
@Override
public Opt<Response> route(final Request req) throws IOException {
final Iterator<String> headers =
new RqHeaders.Base(req).header("Accept-Encoding").iterator();
final Opt<Response> resp;
if (this.encoding.isEmpty()) {
resp = new Opt.Single<>(this.origin);
} else if (headers.hasNext()) {
final Collection<String> items = Arrays.asList(
FkEncoding.ENCODING_SEP.split(
new UncheckedText(
new Lowered(
new Trimmed(
new TextOf(headers.next())
)
)
).asString()
)
);
if (items.contains(this.encoding)) {
resp = new Opt.Single<>(this.origin);
} else {
resp = new Opt.Empty<>();
}
} else {
resp = new Opt.Empty<>();
}
return resp;
}
}