001// Licensed under the Apache License, Version 2.0 (the "License");
002// you may not use this file except in compliance with the License.
003// You may obtain a copy of the License at
004//
005// http://www.apache.org/licenses/LICENSE-2.0
006//
007// Unless required by applicable law or agreed to in writing, software
008// distributed under the License is distributed on an "AS IS" BASIS,
009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
010// See the License for the specific language governing permissions and
011// limitations under the License.
012
013package org.apache.tapestry5.internal.services;
014
015import org.apache.tapestry5.MarkupWriter;
016import org.apache.tapestry5.SymbolConstants;
017import org.apache.tapestry5.TapestryConstants;
018import org.apache.tapestry5.http.ContentType;
019import org.apache.tapestry5.http.TapestryHttpSymbolConstants;
020import org.apache.tapestry5.http.services.Request;
021import org.apache.tapestry5.http.services.Response;
022import org.apache.tapestry5.internal.InternalConstants;
023import org.apache.tapestry5.ioc.IOOperation;
024import org.apache.tapestry5.ioc.annotations.Inject;
025import org.apache.tapestry5.ioc.annotations.Symbol;
026import org.apache.tapestry5.json.JSONObject;
027import org.apache.tapestry5.services.MarkupWriterFactory;
028import org.apache.tapestry5.services.PartialMarkupRenderer;
029
030import java.io.IOException;
031import java.io.PrintWriter;
032
033public class AjaxPartialResponseRendererImpl implements AjaxPartialResponseRenderer
034{
035    private final MarkupWriterFactory factory;
036
037    private final Request request;
038
039    private final Response response;
040
041    private final PartialMarkupRenderer partialMarkupRenderer;
042
043    private final boolean compactJSON;
044
045    private final ContentType contentType;
046
047    public AjaxPartialResponseRendererImpl(MarkupWriterFactory factory,
048
049                                           Request request,
050
051                                           Response response,
052
053                                           PartialMarkupRenderer partialMarkupRenderer,
054
055                                           @Inject
056                                           @Symbol(TapestryHttpSymbolConstants.CHARSET)
057                                           String outputEncoding,
058
059                                           @Symbol(SymbolConstants.COMPACT_JSON)
060                                           boolean compactJSON)
061    {
062        this.factory = factory;
063        this.request = request;
064        this.response = response;
065        this.partialMarkupRenderer = partialMarkupRenderer;
066        this.compactJSON = compactJSON;
067
068        contentType = new ContentType(InternalConstants.JSON_MIME_TYPE).withCharset(outputEncoding);
069    }
070
071    public void renderPartialPageMarkup(final JSONObject reply) throws IOException
072    {
073        assert reply != null;
074
075        request.setAttribute(TapestryConstants.RESPONSE_RENDERER, new IOOperation<Void>()
076        {
077            public Void perform() throws IOException
078            {
079                // This is a complex area as we are trying to keep public and private services properly
080                // separated, and trying to keep stateless and stateful (i.e., perthread scope) services
081                // separated. So we inform the stateful queue service what it needs to do here ...
082
083                String pageName = (String) request.getAttribute(InternalConstants.PAGE_NAME_ATTRIBUTE_NAME);
084
085                if (pageName == null)
086                {
087                    throw new IllegalStateException("The active page name has not been specified.");
088                }
089
090                MarkupWriter writer = factory.newPartialMarkupWriter(pageName);
091
092                // ... and here, the pipeline eventually reaches the PRQ to let it render the root render command.
093
094                partialMarkupRenderer.renderMarkup(writer, reply);
095
096                PrintWriter pw = response.getPrintWriter(contentType.toString());
097
098                reply.print(pw, compactJSON);
099
100                pw.close();
101
102                return null;
103            }
104        });
105    }
106
107    public void renderPartialPageMarkup() throws IOException
108    {
109        renderPartialPageMarkup(new JSONObject());
110    }
111}