src/main/java/org/apache/cassandra/sidecar/routes/StreamSSTableComponentHandler.java

/*
 * 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.cassandra.sidecar.routes;

import java.io.FileNotFoundException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.inject.Inject;
import com.google.inject.Singleton;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.vertx.core.http.HttpServerRequest;
import io.vertx.core.net.SocketAddress;
import io.vertx.ext.web.RoutingContext;
import io.vertx.ext.web.handler.HttpException;
import org.apache.cassandra.sidecar.cluster.InstancesConfig;
import org.apache.cassandra.sidecar.common.data.StreamSSTableComponentRequest;
import org.apache.cassandra.sidecar.snapshots.SnapshotPathBuilder;

/**
 * This handler validates that the component exists in the cluster and sets up the context
 * for the {@link FileStreamHandler} to stream the component back to the client
 */
@Singleton
public class StreamSSTableComponentHandler extends AbstractHandler
{
    private static final Logger logger = LoggerFactory.getLogger(StreamSSTableComponentHandler.class);

    private final SnapshotPathBuilder snapshotPathBuilder;

    @Inject
    public StreamSSTableComponentHandler(SnapshotPathBuilder snapshotPathBuilder, InstancesConfig instancesConfig)
    {
        super(instancesConfig);
        this.snapshotPathBuilder = snapshotPathBuilder;
    }

    @Override
    public void handle(RoutingContext context)
    {
        final HttpServerRequest request = context.request();
        final String host = getHost(context);
        final SocketAddress remoteAddress = request.remoteAddress();
        final StreamSSTableComponentRequest requestParams = extractParamsOrThrow(context);
        logger.debug("StreamSSTableComponentHandler received request: {} from: {}. Instance: {}", requestParams,
                     remoteAddress, host);

        snapshotPathBuilder.build(host, requestParams)
                           .onSuccess(path ->
                           {
                               logger.debug("StreamSSTableComponentHandler handled {} for client {}. Instance: {}",
                                            path, remoteAddress, host);
                               context.put(FileStreamHandler.FILE_PATH_CONTEXT_KEY, path)
                                      .next();
                           })
                           .onFailure(cause ->
                           {
                               String errMsg =
                               "StreamSSTableComponentHandler failed for request: {} from: {}. Instance: {}";
                               logger.error(errMsg, requestParams, remoteAddress, host);
                               if (cause instanceof FileNotFoundException)
                               {
                                   context.fail(new HttpException(HttpResponseStatus.NOT_FOUND.code(),
                                                                  cause.getMessage()));
                               }
                               else
                               {
                                   context.fail(new HttpException(HttpResponseStatus.BAD_REQUEST.code(),
                                                                  "Invalid request for " + requestParams));
                               }
                           });
    }

    private StreamSSTableComponentRequest extractParamsOrThrow(final RoutingContext rc)
    {
        return new StreamSSTableComponentRequest(rc.pathParam("keyspace"),
                                                 rc.pathParam("table"),
                                                 rc.pathParam("snapshot"),
                                                 rc.pathParam("component")
        );
    }
}