/*
* 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.apache.shindig.gadgets;
import org.apache.shindig.common.uri.Uri;
import org.apache.shindig.common.util.ResourceLoader;
import org.apache.shindig.gadgets.http.HttpFetcher;
import org.apache.shindig.gadgets.http.HttpRequest;
import org.apache.shindig.gadgets.http.HttpResponse;
import java.io.File;
import java.io.IOException;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.google.common.base.Objects;
/**
* Represents a javascript library, either as an external resource (url)
* or as an inline script.
*/
public class JsLibrary {
private final Type type;
public Type getType() {
return type;
}
/**
* The content of the library. May be optimized through minification or
* other compression techniques. Use debugContent to get the unmodified
* version.
*/
private final String content;
public String getContent() {
return content;
}
/**
* Unmodified content. May be identical to content if no optimized version of
* the script exists.
*/
private final String debugContent;
public String getDebugContent() {
return debugContent;
}
/**
* The feature that this library belongs to; may be null;
*/
private final String feature;
public String getFeature() {
return feature;
}
private static final Logger logger
= Logger.getLogger("org.apache.shindig.gadgets");
@Override
public String toString() {
if (type == Type.URL) {
return "<script src=\"" + getContent() + "\"></script>";
} else {
return "<script><!--\n" + getContent() + "\n--></script>";
}
}
/**
* Indicates how to load a given resource.
*/
public enum Type {
FILE, RESOURCE, URL, INLINE;
/**
* Returns the type named by the given string.
*/
public static Type parse(String name) {
if ("file".equals(name)) {
return FILE;
} else if ("url".equals(name)) {
return URL;
} else if ("resource".equals(name)) {
return RESOURCE;
} else {
return INLINE;
}
}
}
/**
* Creates a new js library.
*
* @param type If FILE or RESOURCE, the content will be loaded from disk.
* if URL or INLINE, the content will be handled the same as html <script>
* @param content If FILE or RESOURCE, we will also look for a file
* named file.opt.ext for every file.ext, and if present we will
* use that as the standard content and file.ext as the debug content.
* @param feature The name of the feature that this library was created for
* may be null.
* @param fetcher Used to retrieve Type.URL; if null, Type.URL will not be
* kept as a url reference, otherwise the file will be fetched and treated
* as a FILE type.
* @return The newly created library.
* @throws GadgetException
*/
public static JsLibrary create(Type type, String content, String feature,
HttpFetcher fetcher) throws GadgetException {
String optimizedContent = null;
String debugContent;
switch (type) {
case FILE:
case RESOURCE:
StringBuffer opt = new StringBuffer();
StringBuffer dbg = new StringBuffer();
loadOptimizedAndDebugData(content, type, opt, dbg);
optimizedContent = opt.toString();
debugContent = dbg.toString();
break;
case URL:
if (fetcher == null) {
debugContent = optimizedContent = content;
} else {
type = Type.FILE;
debugContent = optimizedContent = loadDataFromUrl(content, fetcher);
}
break;
default:
debugContent = content;
optimizedContent = content;
break;
}
return new JsLibrary(feature, type, optimizedContent, debugContent);
}
/**
* Helper method to load debug and optimized content from a path and type.
* Only supports types FILE and RESOURCE.
*/
protected static void loadOptimizedAndDebugData(String content, Type type, StringBuffer opt,
StringBuffer dbg) {
String opt_data = null;
if (content.endsWith(".js")) {
opt_data =loadData(content.substring(0, content.length() - 3) + ".opt.js", type);
}
String dbg_data = loadData(content, type);
if (dbg_data == null && opt_data == null) {
throw new IllegalArgumentException("Problems reading resource " + content);
} else if (dbg_data == null) {
dbg_data = opt_data;
} else if (opt_data == null) {
opt_data = dbg_data;
}
dbg.append(dbg_data);
opt.append(opt_data);
}
/**
* Loads an external resource.
* @param name
* @param type
* @return The contents of the file or resource named by @code name.
*/
protected static String loadData(String name, Type type) {
if (logger.isLoggable(Level.FINE)) logger.fine("Loading js from: " + name + " type: " + type.toString());
if (type == Type.FILE) {
return loadFile(name);
} else if (type == Type.RESOURCE) {
return loadResource(name);
}
return null;
}
/**
* Retrieves js content from the given url.
*
* @param url
* @param fetcher
* @return The contents of the JS file, or null if it can't be fetched.
* @throws GadgetException
*/
private static String loadDataFromUrl(String url, HttpFetcher fetcher) throws GadgetException {
try {
logger.info("Attempting to load js from: " + url);
Uri uri = Uri.parse(url);
HttpRequest request = new HttpRequest(uri);
HttpResponse response = fetcher.fetch(request);
if (response.getHttpStatusCode() == HttpResponse.SC_OK) {
return response.getResponseAsString();
} else {
logger.warning("Unable to retrieve remote library from " + url);
return null;
}
} catch (IllegalArgumentException e) {
logger.log(Level.WARNING, "Malformed URL: " + url, e);
return null;
}
}
/**
* Loads a file
* @param fileName
* @return The contents of the file.
*/
private static String loadFile(String fileName) {
if (fileName == null) {
// Valid case: no JS needed for container or gadget for feature.
// Blank String provided for this case.
return "";
}
File file = new File(fileName);
if (!file.exists()) {
logger.warning("File not found: " + fileName);
return null;
}
if (!file.isFile()) {
logger.warning("JsLibrary is not a file: " + fileName);
return null;
}
if (!file.canRead()) {
logger.warning("JsLibrary cannot be read: " + fileName);
return null;
}
try {
return ResourceLoader.getContent(file);
} catch (IOException e) {
logger.warning("Error reading file: " + fileName);
return null;
}
}
/**
* Loads a resource.
* @param name
* @return The contents of the named resource.
*/
private static String loadResource(String name) {
try {
return ResourceLoader.getContent(name);
} catch (IOException e) {
logger.warning("Could not find resource: " + name + '-' + e.getMessage());
return null;
}
}
@Override
public int hashCode() {
return Objects.hashCode(content, type);
}
@Override
public boolean equals(Object rhs) {
if (rhs == this) {
return true;
}
if (rhs instanceof JsLibrary) {
JsLibrary lib = (JsLibrary)rhs;
return content.equals(lib.content) && type == lib.type;
}
return false;
}
/**
* @param feature
* @param type
* @param content
* @param debugContent
*/
protected JsLibrary(String feature, Type type, String content,
String debugContent) {
// Validate that we have something here.
if (content == null && debugContent == null) {
throw new IllegalArgumentException("no content for feature " + feature);
}
if (content == null || "null".equals(content) || content.length() == 0) {
content = debugContent;
}
if (debugContent == null || "null".equals(debugContent) || debugContent.length() == 0) {
debugContent = content;
}
this.feature = feature;
this.type = type;
this.content = content;
this.debugContent = debugContent;
}
}