ratpack.rocker.internal.DefaultRockerRenderer.java Source code

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Here is the source code for ratpack.rocker.internal.DefaultRockerRenderer.java

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/*
 * Copyright 2017 the original author or authors.
 *
 * Licensed 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 ratpack.rocker.internal;

import com.fizzed.rocker.ContentType;
import com.fizzed.rocker.RockerModel;
import com.fizzed.rocker.runtime.ArrayOfByteArraysOutput;
import com.google.common.collect.Iterables;
import com.google.inject.Singleton;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.CompositeByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.buffer.UnpooledByteBufAllocator;
import io.netty.util.AsciiString;
import ratpack.handling.Context;
import ratpack.render.RendererException;
import ratpack.render.RendererSupport;
import ratpack.rocker.RockerRenderer;

import java.util.List;

@Singleton
public final class DefaultRockerRenderer extends RendererSupport<RockerModel> implements RockerRenderer {

    private static final AsciiString HTML = AsciiString.of("text/html;charset=UTF-8");
    private static final AsciiString TEXT = AsciiString.of("text/plain;charset=UTF-8");

    public static final RockerRenderer INSTANCE = new DefaultRockerRenderer();

    @Override
    public void render(Context context, RockerModel rockerModel) throws Exception {
        try {
            ArrayOfByteArraysOutput output = rockerModel.render(ArrayOfByteArraysOutput.FACTORY);

            List<byte[]> arrays = output.getArrays();
            ByteBuf byteBuf;
            int size = arrays.size();
            if (size == 0) {
                byteBuf = Unpooled.EMPTY_BUFFER;
            } else if (size == 1) {
                byteBuf = Unpooled.wrappedBuffer(arrays.get(0));
            } else {
                byteBuf = new CompositeByteBuf(UnpooledByteBufAllocator.DEFAULT, false, size,
                        Iterables.transform(arrays, Unpooled::wrappedBuffer));
            }

            AsciiString contentType = output.getContentType() == ContentType.HTML ? HTML : TEXT;
            context.getResponse().contentTypeIfNotSet(contentType).send(byteBuf);

        } catch (Exception e) {
            // https://github.com/fizzed/rocker/issues/30
            // Ratpack will try to toString() the rockerModel object, to create an exception message for the RenderException
            // This will obscure the underlying exception. Log here so we can actually see it.
            // This can be removed when the above issue is rectified.
            throw new RendererException("Error rendering template " + rockerModel.getClass().getName(), e);
        }
    }

}