src/main/java/org/takes/rs/RsHeaders.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.rs;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import lombok.EqualsAndHashCode;
import org.cactoos.text.FormattedText;
import org.cactoos.text.Lowered;
import org.cactoos.text.TextOf;
import org.cactoos.text.Trimmed;
import org.cactoos.text.UncheckedText;
import org.takes.HttpException;
import org.takes.Response;
import org.takes.misc.VerboseList;
/**
* HTTP headers parsing.
*
* <p>All implementations of this interface must be immutable and
* thread-safe.</p>
*
* @since 0.1
*/
@SuppressWarnings("PMD.TooManyMethods")
public interface RsHeaders extends Response {
/**
* Get single header.
*
* @param key Header name
* @return List of values (can be empty)
* @throws IOException If fails
*/
List<String> header(CharSequence key) throws IOException;
/**
* Get all header names.
*
* @return All names
* @throws IOException If fails
*/
Set<String> names() throws IOException;
/**
* Request decorator, for HTTP headers parsing.
*
* <p>The class is immutable and thread-safe.
*
* @since 0.13.8
*/
@EqualsAndHashCode(callSuper = true)
final class Base extends RsWrap implements RsHeaders {
/**
* Ctor.
*
* @param req Original request
*/
public Base(final Response req) {
super(req);
}
@Override
public List<String> header(final CharSequence key)
throws IOException {
final List<String> values = this.map().getOrDefault(
new UncheckedText(
new Lowered(key.toString())
).asString(),
Collections.emptyList()
);
final List<String> list;
if (values.isEmpty()) {
list = new VerboseList<>(
Collections.emptyList(),
new FormattedText(
"There are no headers by name \"%s\" among %d others: %s",
key,
this.map().size(),
this.map().keySet()
)
);
} else {
list = new VerboseList<>(
values,
new FormattedText(
"There are only %d headers by name \"%s\"",
values.size(),
key
)
);
}
return list;
}
@Override
public Set<String> names() throws IOException {
return this.map().keySet();
}
/**
* Parse them all in a map.
*
* @return Map of them
* @throws IOException If fails
*/
@SuppressWarnings("PMD.AvoidInstantiatingObjectsInLoops")
private Map<String, List<String>> map() throws IOException {
final Iterator<String> head = this.head().iterator();
if (!head.hasNext()) {
throw new HttpException(
HttpURLConnection.HTTP_BAD_REQUEST,
"A valid request must contain at least one line in the head"
);
}
head.next();
int pos = 1;
final Map<String, List<String>> map = new HashMap<>(0);
while (head.hasNext()) {
final String line = head.next();
final String[] parts = line.split(":", 2);
if (parts.length < 2) {
throw new HttpException(
HttpURLConnection.HTTP_BAD_REQUEST,
String.format(
"Invalid HTTP header on line #%d: \"%s\"",
pos, line
)
);
}
final String key = new UncheckedText(
new Lowered(new Trimmed(new TextOf(parts[0])))
).asString();
if (!map.containsKey(key)) {
map.put(key, new LinkedList<>());
}
map.get(key).add(
new UncheckedText(
new Trimmed(new TextOf(parts[1]))
).asString()
);
pos += 1;
}
return map;
}
}
/**
* Smart decorator, with extra features.
*
* <p>The class is immutable and thread-safe.
*
* @since 0.16
*/
@EqualsAndHashCode
final class Smart implements RsHeaders {
/**
* Original.
*/
private final RsHeaders origin;
/**
* Ctor.
* @param req Original request
*/
public Smart(final RsHeaders req) {
this.origin = req;
}
/**
* Ctor.
* @param req Original request
*/
public Smart(final Response req) {
this(new RsHeaders.Base(req));
}
@Override
public List<String> header(final CharSequence name)
throws IOException {
return this.origin.header(name);
}
@Override
public Set<String> names() throws IOException {
return this.origin.names();
}
@Override
public Iterable<String> head() throws IOException {
return this.origin.head();
}
@Override
public InputStream body() throws IOException {
return this.origin.body();
}
/**
* Get single header or throw HTTP exception.
* @param name Name of header
* @return Value of it
* @throws IOException If fails
*/
public String single(final CharSequence name) throws IOException {
final Iterator<String> params = this.header(name).iterator();
if (!params.hasNext()) {
throw new HttpException(
HttpURLConnection.HTTP_BAD_REQUEST,
String.format(
"Header \"%s\" is mandatory, not found among %s",
name, this.names()
)
);
}
return params.next();
}
/**
* If header is present, returns the first header value.
* If not, returns a default value.
* @param name Name of header key
* @param def Default value
* @return Header Value or default value
* @throws IOException If fails
*/
public String single(final CharSequence name, final CharSequence def)
throws IOException {
final String value;
final Iterator<String> params = this.header(name).iterator();
if (params.hasNext()) {
value = params.next();
} else {
value = def.toString();
}
return value;
}
}
}