/*
* 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.shindig.gadgets.render;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Logger;
import java.util.logging.Level;
import org.apache.shindig.config.ContainerConfig;
import org.apache.shindig.gadgets.http.HttpFetcher;
import org.apache.shindig.gadgets.http.HttpRequest;
import org.apache.shindig.gadgets.http.HttpResponse;
import org.apache.shindig.gadgets.GadgetException;
import org.apache.shindig.common.uri.Uri;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.LinkedHashMultimap;
import com.google.common.collect.Multimap;
import com.google.common.collect.Sets;
import com.google.common.collect.ImmutableList;
import com.google.inject.Inject;
/**
* Retrieves the rpc services for a container by fetching them from the container's
* system.listMethods endpoints as defined in the container config.
*/
public class DefaultServiceFetcher {
static final Logger logger = Logger.getLogger(Renderer.class.getName());
static final String JSON_RESPONSE_WRAPPER_ELEMENT = "data";
static final String OSAPI_FEATURE_CONFIG = "osapi";
static final String OSAPI_SERVICES = "osapi.services";
static final String GADGETS_FEATURES_CONFIG = "gadgets.features";
static final String SYSTEM_LIST_METHODS_METHOD = "system.listMethods";
/** Key in container config that lists the endpoints offering services */
static final String OSAPI_BASE_ENDPOINTS = "endPoints";
private final ContainerConfig containerConfig;
private final HttpFetcher fetcher;
/** @param config Container Config for looking up endpoints */
@Inject
public DefaultServiceFetcher(ContainerConfig config, HttpFetcher fetcher) {
this.containerConfig = config;
this.fetcher = fetcher;
}
/**
* Returns the services, keyed by endpoint for the given container.
*
* @param container The particular container whose services we want.
* @return Map endpoints and their serviceMethod list
*/
public Multimap<String, String> getServicesForContainer(String container, String host) {
if (containerConfig == null) {
return ImmutableMultimap.<String, String>builder().build();
}
LinkedHashMultimap<String, String> endpointServices = LinkedHashMultimap.create();
// First check services directly declared in container config
@SuppressWarnings("unchecked")
Map<String, Object> declaredServices = (Map<String, Object>) containerConfig.getMap(container,
GADGETS_FEATURES_CONFIG).get(OSAPI_SERVICES);
if (declaredServices != null) {
for (Map.Entry<String, Object> entry : declaredServices.entrySet()) {
@SuppressWarnings("unchecked")
Iterable<String> entryValue = (Iterable<String>) entry.getValue();
endpointServices.putAll(entry.getKey(), entryValue);
}
}
// Merge services lazily loaded from the endpoints if any
List<String> endpoints = getEndpointsFromContainerConfig(container, host);
for (String endpoint : endpoints) {
endpointServices.putAll(endpoint, retrieveServices(endpoint.replace("%host%", host)));
}
return ImmutableMultimap.copyOf(endpointServices);
}
@SuppressWarnings("unchecked")
private List<String> getEndpointsFromContainerConfig(String container, String host) {
@SuppressWarnings("unchecked")
Map<String, Object> properties = (Map<String, Object>) containerConfig.getMap(container,
GADGETS_FEATURES_CONFIG).get(OSAPI_FEATURE_CONFIG);
if (properties != null) {
return (List<String>) properties.get(OSAPI_BASE_ENDPOINTS);
}
return ImmutableList.of();
}
private Set<String> retrieveServices(String endpoint) {
Uri url = Uri.parse(endpoint + "?method=" + SYSTEM_LIST_METHODS_METHOD);
HttpRequest request = new HttpRequest(url);
try {
HttpResponse response = fetcher.fetch(request);
if (response.getHttpStatusCode() == HttpResponse.SC_OK) {
return getServicesFromJsonResponse(response.getResponseAsString());
} else {
logger.log(Level.SEVERE, "HTTP Error " + response.getHttpStatusCode() +
" fetching service methods from endpoint " + endpoint);
}
} catch (GadgetException ge) {
logger.log(Level.SEVERE, "Failed to fetch services methods from endpoint " + endpoint +
". Error " + ge.getMessage());
} catch (JSONException je) {
logger.log(Level.SEVERE, "Failed to parse services methods from endpoint " + endpoint +
". " + je.getMessage());
}
return ImmutableSet.of();
}
private Set<String> getServicesFromJsonResponse(String content)
throws JSONException {
ImmutableSet.Builder<String> services = ImmutableSet.builder();
JSONObject js = new JSONObject(content);
JSONArray json = js.getJSONArray(JSON_RESPONSE_WRAPPER_ELEMENT);
for (int i = 0; i < json.length(); i++) {
String o = json.getString(i);
services.add(o);
}
return services.build();
}
}