/**
* Copyright (C) 2014 Couchbase, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALING
* IN THE SOFTWARE.
*/
package com.couchbase.client.core.config.loader;
import com.couchbase.client.core.ClusterFacade;
import com.couchbase.client.core.config.BucketConfig;
import com.couchbase.client.core.config.LoaderType;
import com.couchbase.client.core.config.parser.BucketConfigParser;
import com.couchbase.client.core.env.CoreEnvironment;
import com.couchbase.client.core.lang.Tuple;
import com.couchbase.client.core.lang.Tuple2;
import com.couchbase.client.core.message.internal.AddNodeRequest;
import com.couchbase.client.core.message.internal.AddNodeResponse;
import com.couchbase.client.core.message.internal.AddServiceRequest;
import com.couchbase.client.core.message.internal.AddServiceResponse;
import com.couchbase.client.core.service.ServiceType;
import rx.Observable;
import rx.functions.Func1;
import java.net.InetAddress;
import java.util.Set;
/**
* An {@link AbstractLoader} which provides common basic processing for all implementing loaders.
*
* A loader fetches configuration from a service, maybe falls back to another service and finally response with a
* {@link BucketConfig} or an error. There are multiple steps, like making sure that a node or service is alive before
* sending a request into, is abstracted in here to avoid duplication.
*
* @author Michael Nitschinger
* @since 1.0
*/
public abstract class AbstractLoader implements Loader {
/**
* The reference to the cluster.
*/
private final ClusterFacade cluster;
/**
* The couchbase environment.
*/
private final CoreEnvironment environment;
/**
* The service serviceType from the actual loader implementation.
*/
private final ServiceType serviceType;
private final LoaderType loaderType;
/**
* Create a new {@link AbstractLoader}.
*
* @param serviceType the service serviceType.
* @param cluster the cluster reference.
* @param environment the couchbase environment.
*/
protected AbstractLoader(final LoaderType loaderType, final ServiceType serviceType, final ClusterFacade cluster, final CoreEnvironment environment) {
this.loaderType = loaderType;
this.serviceType = serviceType;
this.cluster = cluster;
this.environment = environment;
}
/**
* Port to use for the {@link ServiceType}.
*
* This method needs to be implemented by the actual loader and defines the port which should be used to
* connect the service to. In practice, the actual port may depend on the environment (i.e. if SSL is used or not).
*
* @return the port for the service to enable.
*/
protected abstract int port();
/**
* Run the {@link BucketConfig} discovery process.
*
* @param bucket the name of the bucket.
* @param password the password of the bucket.
* @param hostname the hostname of the seed node list.
* @return a raw config if discovered.
*/
protected abstract Observable<String> discoverConfig(String bucket, String password, InetAddress hostname);
/**
* Initiate the config loading process.
*
* The common path handled by this abstract implementation includes making sure that the node and service are
* usable by the actual implementation. Finally, the raw config string config parsing is handled in this central
* place.
*
* @param seedNodes the seed nodes.
* @param bucket the name of the bucket.
* @param password the password of the bucket.
* @return a valid {@link BucketConfig}.
*/
public Observable<Tuple2<LoaderType, BucketConfig>> loadConfig(final Set<InetAddress> seedNodes, final String bucket,
final String password) {
return Observable
.from(seedNodes)
.subscribeOn(env().scheduler())
.flatMap(new Func1<InetAddress, Observable<AddNodeResponse>>() {
@Override
public Observable<AddNodeResponse> call(final InetAddress address) {
return cluster.send(new AddNodeRequest(address));
}
}).flatMap(new Func1<AddNodeResponse, Observable<AddServiceResponse>>() {
@Override
public Observable<AddServiceResponse> call(final AddNodeResponse response) {
if (!response.status().isSuccess()) {
return Observable.error(new IllegalStateException("Could not add node for config loading."));
}
return cluster.send(
new AddServiceRequest(serviceType, bucket, password, port(), response.hostname())
);
}
}).flatMap(new Func1<AddServiceResponse, Observable<String>>() {
@Override
public Observable<String> call(final AddServiceResponse response) {
if (!response.status().isSuccess()) {
return Observable.error(new IllegalStateException("Could not add service for config loading."));
}
return discoverConfig(bucket, password, response.hostname());
}
})
.observeOn(env().scheduler())
.map(new Func1<String, Tuple2<LoaderType, BucketConfig>>() {
@Override
public Tuple2<LoaderType, BucketConfig> call(final String rawConfig) {
BucketConfig config = BucketConfigParser.parse(rawConfig);
config.password(password);
return Tuple.create(loaderType, config);
}
});
}
/**
* Returns the {@link ClusterFacade} for child implementations.
*
* @return the cluster reference.
*/
protected ClusterFacade cluster() {
return cluster;
}
/**
* Returns the {@link CoreEnvironment} for child implementations.
*
* @return the environment.
*/
protected CoreEnvironment env() {
return environment;
}
/**
* Replaces the host wildcard from an incoming config with a proper hostname.
*
* @param input the input config.
* @param hostname the hostname to replace it with.
* @return a replaced configuration.
*/
protected String replaceHostWildcard(String input, InetAddress hostname) {
return input.replace("$HOST", hostname.getHostName());
}
}