/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. 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. For additional information regarding
* copyright in this work, please see the NOTICE file in the top level
* directory of this distribution.
*/
package org.apache.abdera.protocol.server.impl;
import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
import javax.activation.MimeType;
import org.apache.abdera.Abdera;
import org.apache.abdera.factory.Factory;
import org.apache.abdera.i18n.iri.IRI;
import org.apache.abdera.i18n.text.UrlEncoding;
import org.apache.abdera.i18n.text.CharUtils.Profile;
import org.apache.abdera.model.AtomDate;
import org.apache.abdera.model.Content;
import org.apache.abdera.model.Entry;
import org.apache.abdera.model.Feed;
import org.apache.abdera.model.Person;
import org.apache.abdera.model.Text;
import org.apache.abdera.parser.ParseException;
import org.apache.abdera.protocol.server.ProviderHelper;
import org.apache.abdera.protocol.server.RequestContext;
import org.apache.abdera.protocol.server.ResponseContext;
import org.apache.abdera.protocol.server.context.EmptyResponseContext;
import org.apache.abdera.protocol.server.context.MediaResponseContext;
import org.apache.abdera.protocol.server.context.ResponseContextException;
import org.apache.abdera.util.EntityTag;
import org.apache.abdera.util.MimeTypeHelper;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* By extending this class it becomes easy to build Collections which are
* backed by a set of entities - such as a database row, domain objects, or
* files.
* @param <T> The entity that this is backed by.
*/
public abstract class AbstractEntityCollectionAdapter<T>
extends AbstractCollectionAdapter {
private final static Log log = LogFactory.getLog(AbstractEntityCollectionAdapter.class);
/**
* Create a new entry
* @param title The title of the entry (assumes that type="text")
* @param id The value of the atom:id element
* @param summary The summary of the entry
* @param updated The value of the atom:updated element
* @param authors Listing of atom:author elements
* @param context The content of the entry
* @param request The request context
*/
public abstract T postEntry(
String title,
IRI id,
String summary,
Date updated,
List<Person> authors,
Content content,
RequestContext request)
throws ResponseContextException;
@Override
public ResponseContext postMedia(RequestContext request) {
return createMediaEntry(request);
}
@Override
public ResponseContext putMedia(RequestContext request) {
try {
String id = getResourceName(request);
T entryObj = getEntry(id, request);
putMedia(entryObj, request.getContentType(), request.getSlug(),
request.getInputStream(), request);
return new EmptyResponseContext(200);
} catch (IOException e) {
return new EmptyResponseContext(500);
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
/**
* Update a media resource. By default this method is not allowed. Implementations
* must override this method to support media resource updates
* @param entryObj
* @param contentType The mime-type of the media resource
* @param slug The value of the Slug request header
* @param inputStream An input stream providing access to the request payload
* @param request The request context
*/
public void putMedia(
T entryObj,
MimeType contentType,
String slug,
InputStream inputStream,
RequestContext request)
throws ResponseContextException {
throw new ResponseContextException(ProviderHelper.notallowed(request));
}
public ResponseContext postEntry(RequestContext request) {
return createNonMediaEntry(request);
}
protected String getLink(
T entryObj,
IRI feedIri,
RequestContext request)
throws ResponseContextException {
return getLink(entryObj, feedIri, request, false);
}
protected String getLink(
T entryObj,
IRI feedIri,
RequestContext request,
boolean absolute)
throws ResponseContextException {
return getLink(getName(entryObj), entryObj, feedIri, request, absolute);
}
protected String getLink(
String name,
T entryObj,
IRI feedIri,
RequestContext request) {
return getLink(name, entryObj, feedIri, request, false);
}
protected String getLink(
String name,
T entryObj,
IRI feedIri,
RequestContext request,
boolean absolute) {
feedIri = feedIri.trailingSlash();
IRI entryIri = feedIri.resolve(UrlEncoding.encode(name, Profile.PATH.filter()));
if (absolute) {
entryIri = request.getResolvedUri().resolve(entryIri);
}
String link = entryIri.toString();
String qp = getQueryParameters(entryObj, request);
if (qp != null && !"".equals(qp)) {
StringBuilder sb = new StringBuilder();
sb.append(link)
.append("?")
.append(qp);
link = sb.toString();
}
return link;
}
protected String getQueryParameters(T entryObj, RequestContext request) {
return null;
}
/**
* Post a new media resource to the collection. By default, this method is
* not supported. Implementations must override this method to support posting
* media resources
* @param mimeType The mime-type of the resource
* @param slug The value of the Slug header
* @param inputStream An InputStream providing access to the request payload
* @param request The request context
*/
public T postMedia(
MimeType mimeType,
String slug,
InputStream inputStream,
RequestContext request)
throws ResponseContextException {
throw new UnsupportedOperationException();
}
public ResponseContext deleteEntry(RequestContext request) {
String id = getResourceName(request);
if (id != null) {
try {
deleteEntry(id, request);
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
return new EmptyResponseContext(204);
} else {
// TODO: is this right?
return new EmptyResponseContext(404);
}
}
/**
* Delete an entry
* @param resourceName The entry to delete
* @param request The request context
*/
public abstract void deleteEntry(
String resourceName,
RequestContext request)
throws ResponseContextException;
public ResponseContext deleteMedia(RequestContext request) {
String resourceName = getResourceName(request);
if (resourceName != null) {
try {
deleteMedia(resourceName, request);
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
return new EmptyResponseContext(204);
} else {
// TODO: is this right?
return new EmptyResponseContext(404);
}
}
/**
* Delete a media resource. By default this method is not supported. Implementations
* must override this method to support deleting media resources
*/
public void deleteMedia(
String resourceName,
RequestContext request)
throws ResponseContextException {
throw new ResponseContextException(ProviderHelper.notsupported(request));
}
/**
* Get the authors for an entry. By default this returns null. Implementations
* must override in order to providing a listing of authors for an entry
*/
public List<Person> getAuthors(
T entry,
RequestContext request)
throws ResponseContextException {
return null;
}
/**
* Get the content for the entry.
*/
public abstract Object getContent(
T entry,
RequestContext request)
throws ResponseContextException;
// GET, POST, PUT, DELETE
/**
* Get the content-type for the entry. By default this operation is not supported.
*/
public String getContentType(T entry) {
throw new UnsupportedOperationException();
}
/**
* Get the listing of entries requested
*/
public abstract Iterable<T> getEntries(
RequestContext request)
throws ResponseContextException;
public ResponseContext getEntry(RequestContext request) {
try {
Entry entry = getEntryFromCollectionProvider(request);
if (entry != null) {
return buildGetEntryResponse(request, entry);
} else {
return new EmptyResponseContext(404);
}
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
/**
* Get a specific entry
* @param resourceName The entry to get
* @param request The request context
*/
public abstract T getEntry(
String resourceName,
RequestContext request)
throws ResponseContextException;
public ResponseContext headEntry(RequestContext request) {
try {
String resourceName = getResourceName(request);
T entryObj = getEntry(resourceName, request);
if (entryObj != null) {
return buildHeadEntryResponse(request, resourceName, getUpdated(entryObj));
} else {
return new EmptyResponseContext(404);
}
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
public ResponseContext headMedia(RequestContext request) {
try {
String resourceName = getResourceName(request);
T entryObj = getEntry(resourceName, request);
if (entryObj != null) {
return buildHeadEntryResponse(request, resourceName, getUpdated(entryObj));
} else {
return new EmptyResponseContext(404);
}
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
public ResponseContext getFeed(RequestContext request) {
try {
Feed feed = createFeedBase(request);
addFeedDetails(feed, request);
return buildGetFeedResponse(feed);
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
/**
* Adds the selected entries to the Feed document. By default, this will set
* the feed's atom:updated element to the current date and time
*/
protected void addFeedDetails(
Feed feed,
RequestContext request)
throws ResponseContextException {
feed.setUpdated(new Date());
Iterable<T> entries = getEntries(request);
if (entries != null) {
for (T entryObj : entries) {
Entry e = feed.addEntry();
IRI feedIri = new IRI(getFeedIriForEntry(entryObj, request));
addEntryDetails(request, e, feedIri, entryObj);
if (isMediaEntry(entryObj)) {
addMediaContent(feedIri, e, entryObj, request);
} else {
addContent(e, entryObj, request);
}
}
}
}
private IRI getFeedIRI(T entryObj, RequestContext request) {
String feedIri = getFeedIriForEntry(entryObj, request);
return new IRI(feedIri).trailingSlash();
}
/**
* Gets the UUID for the specified entry.
* @param entry
* @return
*/
public abstract String getId(T entry) throws ResponseContextException;
public ResponseContext getMedia(RequestContext request) {
try {
String resource = getResourceName(request);
T entryObj = getEntry(resource, request);
if (entryObj == null) {
return new EmptyResponseContext(404);
}
return buildGetMediaResponse(resource, entryObj);
} catch (ParseException pe) {
return new EmptyResponseContext(415);
} catch (ClassCastException cce) {
return new EmptyResponseContext(415);
} catch (ResponseContextException e) {
return e.getResponseContext();
} catch (Exception e) {
log.warn(e.getMessage(), e);
return new EmptyResponseContext(400);
}
}
/**
* Creates a ResponseContext for a GET media request. By default, this returns
* a MediaResponseContext containing the media resource. The last-modified
* header will be set.
*/
protected ResponseContext buildGetMediaResponse(
String id,
T entryObj)
throws ResponseContextException {
Date updated = getUpdated(entryObj);
MediaResponseContext ctx = new MediaResponseContext(getMediaStream(entryObj),
updated,
200);
ctx.setContentType(getContentType(entryObj));
ctx.setEntityTag(EntityTag.generate(id, AtomDate.format(updated)));
return ctx;
}
/**
* Get the name of the media resource. By default this method is unsupported.
* Implementations must override.
*/
public String getMediaName(T entry) throws ResponseContextException {
throw new UnsupportedOperationException();
}
/**
* Get an input stream for the media resource. By default this method is unsupported.
* Implementations must override.
*/
public InputStream getMediaStream(T entry) throws ResponseContextException {
throw new UnsupportedOperationException();
}
/**
* Get the name of the entry resource (used to construct links)
*/
public abstract String getName(T entry) throws ResponseContextException;
/**
* Get the title fo the entry
*/
public abstract String getTitle(T entry) throws ResponseContextException;
/**
* Get the value to use in the atom:updated element
*/
public abstract Date getUpdated(T entry) throws ResponseContextException;
/**
* True if this entry is a media-link entry. By default this always returns
* false. Implementations must override to support media link entries
*/
public boolean isMediaEntry(T entry) throws ResponseContextException {
return false;
}
public ResponseContext putEntry(RequestContext request) {
try {
String id = getResourceName(request);
T entryObj = getEntry(id, request);
if (entryObj == null) {
return new EmptyResponseContext(404);
}
Entry orig_entry = getEntryFromCollectionProvider(entryObj, new IRI(getFeedIriForEntry(entryObj, request)), request);
if (orig_entry != null) {
MimeType contentType = request.getContentType();
if (contentType != null && !MimeTypeHelper.isAtom(contentType.toString()))
return new EmptyResponseContext(415);
Entry entry = getEntryFromRequest(request);
if (entry != null) {
if (!entry.getId().equals(orig_entry.getId()))
return new EmptyResponseContext(409);
if (!ProviderHelper.isValidEntry(entry))
return new EmptyResponseContext(400);
putEntry(entryObj, entry.getTitle(), new Date(), entry.getAuthors(),
entry.getSummary(), entry.getContentElement(), request);
return new EmptyResponseContext(204);
} else {
return new EmptyResponseContext(400);
}
} else {
return new EmptyResponseContext(404);
}
} catch (ResponseContextException e) {
return createErrorResponse(e);
} catch (ParseException pe) {
return new EmptyResponseContext(415);
} catch (ClassCastException cce) {
return new EmptyResponseContext(415);
} catch (Exception e) {
log.warn(e.getMessage(), e);
return new EmptyResponseContext(400);
}
}
/**
* Get the Feed IRI
*/
protected String getFeedIriForEntry(
T entryObj,
RequestContext request) {
return getHref(request);
}
/**
* Update an entry.
* @param entry The entry to update
* @param title The new title of the entry
* @param updated The new value of atom:updated
* @param authors To new listing of authors
* @param summary The new summary
* @param content The new content
* @param request The request context
*/
public abstract void putEntry(
T entry,
String title,
Date updated,
List<Person> authors,
String summary,
Content content,
RequestContext request)
throws ResponseContextException;
/**
* Adds the atom:content element to an entry
*/
protected void addContent(
Entry e,
T doc,
RequestContext request)
throws ResponseContextException {
Object content = getContent(doc, request);
if (content instanceof Content) {
e.setContentElement((Content)content);
} else if (content instanceof String) {
e.setContent((String)content);
}
}
/**
* Add the details to an entry
* @param request The request context
* @param e The entry
* @param feedIri The feed IRI
* @param entryObj
*/
protected String addEntryDetails(RequestContext request,
Entry e,
IRI feedIri,
T entryObj) throws ResponseContextException {
String link = getLink(entryObj, feedIri, request);
e.addLink(link, "edit");
e.setId(getId(entryObj));
e.setTitle(getTitle(entryObj));
e.setUpdated(getUpdated(entryObj));
List<Person> authors = getAuthors(entryObj, request);
if (authors != null) {
for (Person a : authors) {
e.addAuthor(a);
}
}
Text t = getSummary(entryObj, request);
if (t != null) {
e.setSummaryElement(t);
}
return link;
}
/**
* Get the summary of the entry. By default this returns null.
*/
public Text getSummary(
T entry,
RequestContext request)
throws ResponseContextException {
return null;
}
/**
* Add media content details to a media-link entry
* @param feedIri The feed iri
* @param entry The entry object
* @param entryObj
* @param request The request context
*/
protected String addMediaContent(IRI feedIri,
Entry entry,
T entryObj,
RequestContext request) throws ResponseContextException {
String name = getMediaName(entryObj);
IRI mediaIri = new IRI(getLink(name, entryObj, feedIri, request));
String mediaLink = mediaIri.toString();
entry.setContent(mediaIri, getContentType(entryObj));
entry.addLink(mediaLink, "edit-media");
return mediaLink;
}
/**
* Create a media entry
* @param request The request context
*/
protected ResponseContext createMediaEntry(RequestContext request) {
try {
T entryObj = postMedia(request.getContentType(),
request.getSlug(),
request.getInputStream(),
request);
IRI feedUri = getFeedIRI(entryObj, request);
Entry entry = request.getAbdera().getFactory().newEntry();
String link = addEntryDetails(request, entry, feedUri, entryObj);
addMediaContent(feedUri, entry, entryObj, request);
String location = getLink(entryObj, feedUri, request, true);
return buildPostMediaEntryResponse(location, entry);
} catch (IOException e) {
return new EmptyResponseContext(500);
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
/**
* Create a regular entry
* @param request The request context
*/
protected ResponseContext createNonMediaEntry(RequestContext request) {
try {
Entry entry = getEntryFromRequest(request);
if (entry != null) {
if (!ProviderHelper.isValidEntry(entry))
return new EmptyResponseContext(400);
entry.setUpdated(new Date());
T entryObj = postEntry(entry.getTitle(),
entry.getId(),
entry.getSummary(),
entry.getUpdated(),
entry.getAuthors(),
entry.getContentElement(),
request);
entry.getIdElement().setValue(getId(entryObj));
IRI feedUri = getFeedIRI(entryObj, request);
String link = getLink(entryObj, feedUri, request);
entry.addLink(link, "edit");
String location = getLink(entryObj, feedUri, request, true);
return buildCreateEntryResponse(location, entry);
} else {
return new EmptyResponseContext(400);
}
} catch (ResponseContextException e) {
return createErrorResponse(e);
}
}
protected Entry getEntryFromCollectionProvider(RequestContext request) throws ResponseContextException {
String id = getResourceName(request);
T entryObj = getEntry(id, request);
if (entryObj == null) {
return null;
}
IRI feedIri = new IRI(getFeedIriForEntry(entryObj, request));
return getEntryFromCollectionProvider(entryObj, feedIri, request);
}
Entry getEntryFromCollectionProvider(T entryObj, IRI feedIri, RequestContext request)
throws ResponseContextException {
Abdera abdera = request.getAbdera();
Factory factory = abdera.getFactory();
Entry entry = factory.newEntry();
return buildEntry(entryObj, entry, feedIri, request);
}
/**
* Build the entry from the source object
* @param entryObj The source object
* @param entry The entry to build
* @param feedIri The feed IRI
* @param request The request context
*/
private Entry buildEntry(T entryObj, Entry entry, IRI feedIri, RequestContext request)
throws ResponseContextException {
addEntryDetails(request, entry, feedIri, entryObj);
if (isMediaEntry(entryObj)) {
addMediaContent(feedIri, entry, entryObj, request);
} else {
addContent(entry, entryObj, request);
}
return entry;
}
}