/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF 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 org.jooby;
import static java.util.Objects.requireNonNull;
import java.io.InputStream;
import java.net.URL;
import com.google.common.io.BaseEncoding;
import com.google.common.primitives.Longs;
/**
* Usually a public file/resource like javascript, css, images files, etc...
* An asset consist of content type, stream and last modified since attributes, between others.
*
* @author edgar
* @since 0.1.0
* @see Jooby#assets(String)
*/
public interface Asset {
/**
* Forwarding asset.
*
* @author edgar
*/
public class Forwarding implements Asset {
private Asset asset;
public Forwarding(final Asset asset) {
this.asset = requireNonNull(asset, "Asset is required.");
}
@Override
public String etag() {
return asset.etag();
}
@Override
public String name() {
return asset.name();
}
@Override
public String path() {
return asset.path();
}
@Override
public URL resource() {
return asset.resource();
}
@Override
public long length() {
return asset.length();
}
@Override
public long lastModified() {
return asset.lastModified();
}
@Override
public InputStream stream() throws Exception {
return asset.stream();
}
@Override
public MediaType type() {
return asset.type();
}
}
/**
* Examples:
*
* <pre>
* GET /assets/index.js {@literal ->} index.js
* GET /assets/js/index.js {@literal ->} index.js
* </pre>
*
* @return The asset name (without path).
*/
default String name() {
String path = path();
int slash = path.lastIndexOf('/');
return path.substring(slash + 1);
}
/**
* Examples:
*
* <pre>
* GET /assets/index.js {@literal ->} /assets/index.js
* GET /assets/js/index.js {@literal ->} /assets/js/index.js
* </pre>
*
* @return The asset requested path, includes the name.
*/
String path();
/**
* @return URL representing the resource.
*/
URL resource();
/**
* @return Generate a weak Etag using the {@link #path()}, {@link #lastModified()} and
* {@link #length()}.
*/
default String etag() {
StringBuilder b = new StringBuilder(32);
b.append("W/\"");
BaseEncoding b64 = BaseEncoding.base64();
int lhash = resource().hashCode();
b.append(b64.encode(Longs.toByteArray(lastModified() ^ lhash)));
b.append(b64.encode(Longs.toByteArray(length() ^ lhash)));
b.append('"');
return b.toString();
}
/**
* @return Asset size (in bytes) or <code>-1</code> if undefined.
*/
long length();
/**
* @return The last modified date if possible or -1 when isn't.
*/
long lastModified();
/**
* @return The content of this asset.
* @throws Exception If content can't be read it.
*/
InputStream stream() throws Exception;
/**
* @return Asset media type.
*/
MediaType type();
}