/*
* Copyright: Almende B.V. (2014), Rotterdam, The Netherlands
* License: The Apache Software License, Version 2.0
*/
package com.almende.eve.state.couch;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.ektorp.CouchDbConnector;
import org.ektorp.CouchDbInstance;
import org.ektorp.http.HttpClient;
import org.ektorp.http.StdHttpClient;
import org.ektorp.http.StdHttpClient.Builder;
import org.ektorp.impl.StdCouchDbInstance;
import com.almende.eve.capabilities.AbstractCapabilityBuilder;
import com.almende.eve.state.State;
import com.almende.eve.state.StateService;
import com.fasterxml.jackson.databind.node.ObjectNode;
/**
* The Class CouchStateBuilder.
*/
public class CouchStateBuilder extends AbstractCapabilityBuilder<CouchState> {
private static final Logger LOG = Logger.getLogger(CouchStateBuilder.class
.getName());
private static Map<String, CouchStateProvider> instances = new ConcurrentHashMap<String, CouchStateProvider>();
@Override
public CouchState build() {
final CouchStateProvider provider = getInstanceByParams(getParams());
if (provider != null) {
return provider.get(getParams());
} else {
LOG.warning("Couldn't get CouchStateProvider instance!");
return null;
}
}
/**
* Gets the instance by params.
*
* @param params
* the params
* @return the instance by params
*/
public CouchStateProvider getInstanceByParams(final ObjectNode params) {
final CouchStateConfig config = new CouchStateConfig(params);
final String key = config.getKey();
if (instances.containsKey(key)) {
return instances.get(key);
} else {
synchronized (instances) {
if (!instances.containsKey(key)) {
final CouchStateProvider result = new CouchStateProvider(
params);
if (result != null) {
instances.put(key, result);
}
}
return instances.get(key);
}
}
}
/**
* The Class CouchStateService.
*/
class CouchStateProvider implements StateService {
private CouchDbConnector db = null;
/**
* Instantiates a new couch state service.
*
* @param params
* the params
*/
public CouchStateProvider(final ObjectNode params) {
try {
final CouchStateConfig config = new CouchStateConfig(params);
final String url = config.getUrl();
final String username = config.getUsername();
final String password = config.getPassword();
final String database = config.getDatabase();
final Builder builder = new StdHttpClient.Builder().url(url);
if (username != null && !username.isEmpty()) {
builder.username(username);
}
if (password != null && !password.isEmpty()) {
builder.password(password);
}
final HttpClient httpClient = builder.build();
final CouchDbInstance dbInstance = new StdCouchDbInstance(
httpClient);
// if the second parameter is true, the database will be created
// if
// it doesn't exists
db = dbInstance.createConnector(database, true);
} catch (final Exception e) {
LOG.log(Level.SEVERE, "Failed to connect to couch db", e);
}
}
/**
* Gets the CouchState.
*
* @param params
* the params
* @return the couch state
*/
public CouchState get(final ObjectNode params) {
final CouchStateConfig config = new CouchStateConfig(params);
final String id = couchify(config.getId());
CouchState state = null;
try {
synchronized (this) {
if (db.contains(id)) {
state = db.get(CouchState.class, id);
state.setDb(db);
state.setService(this);
} else {
state = new CouchState(id, db, this, config);
db.create(state);
}
}
} catch (final Exception e) {
LOG.log(Level.WARNING, "Failed to load agent", e);
}
return state;
}
/*
* (non-Javadoc)
*
* @see
* com.almende.eve.state.StateService#delete(com.almende.eve.state.State)
*/
@Override
public void delete(final State instance) {
db.delete(instance);
}
/**
* Check the key if it starts with a _
* Add a prefix if this is the case, because _ properties are reserved.
*
* @param key
* the key
* @return prefixed key (if necessary)
*/
private String couchify(final String key) {
if (key.startsWith("_")) {
return "cdb" + key;
}
return key;
}
}
}