/**
* 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.ambari.server.api.services;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.ws.rs.core.HttpHeaders;
import javax.ws.rs.core.UriInfo;
import org.apache.ambari.server.api.resources.ResourceDefinition;
import org.apache.ambari.server.api.resources.ResourceInstance;
/**
* Factory for {@link Request} instances.
*/
public class RequestFactory {
/**
* Create a request instance.
*
* @param headers http headers
* @param uriInfo uri information
* @param requestType http request type
* @param resource associated resource instance
*
* @return a new Request instance
*/
public Request createRequest(HttpHeaders headers, RequestBody body, UriInfo uriInfo, Request.Type requestType,
ResourceInstance resource) {
switch (requestType) {
case GET:
return createGetRequest(headers, body, uriInfo, resource);
case PUT:
return createPutRequest(headers, body, uriInfo, resource);
case DELETE:
return createDeleteRequest(headers, body, uriInfo, resource);
case POST:
return createPostRequest(headers, body, uriInfo, resource);
default:
throw new IllegalArgumentException("Invalid request type: " + requestType);
}
}
/**
* Create a GET request. This will apply any eligible directives supplied in the URI.
*
* @param headers http headers
* @param uriInfo uri information
* @param resource associated resource instance
* @return new post request
*/
private Request createGetRequest(HttpHeaders headers, RequestBody body, UriInfo uriInfo, ResourceInstance resource) {
applyDirectives(Request.Type.GET, body, uriInfo, resource);
return new GetRequest(headers, body, uriInfo, resource);
}
/**
* Create a POST request. This will either be a standard post request or a query post request.
* A query post request first applies a query to a collection resource and then creates
* sub-resources to all matches of the predicate.
*
* @param headers http headers
* @param uriInfo uri information
* @param resource associated resource instance
*
* @return new post request
*/
private Request createPostRequest(HttpHeaders headers, RequestBody body, UriInfo uriInfo, ResourceInstance resource) {
boolean batchCreate = !applyDirectives(Request.Type.POST, body, uriInfo, resource);;
return (batchCreate) ?
new QueryPostRequest(headers, body, uriInfo, resource) :
new PostRequest(headers, body, uriInfo, resource);
}
/**
* Creates a PUT request. It will apply any eligible directives supplied in the URI
*/
private Request createPutRequest(HttpHeaders headers, RequestBody body, UriInfo uriInfo, ResourceInstance resource) {
applyDirectives(Request.Type.PUT, body, uriInfo, resource);
return new PutRequest(headers, body, uriInfo, resource);
}
/**
* Creates a DELETE request. It will apply any eligible directives supplied in the URI
*/
private DeleteRequest createDeleteRequest(HttpHeaders headers, RequestBody body, UriInfo uriInfo, ResourceInstance resource) {
applyDirectives(Request.Type.DELETE, body, uriInfo, resource);
return new DeleteRequest(headers, body, uriInfo, resource);
}
/**
* Gather query parameters from uri and body query string.
*
* @param uriInfo contains uri info
* @param body request body
*
* @return map of query parameters or an empty map if no parameters are present
*/
private Map<String, String> getQueryParameters(UriInfo uriInfo, RequestBody body) {
Map<String, String> queryParameters = new HashMap<>();
for (Map.Entry<String, List<String>> entry : uriInfo.getQueryParameters().entrySet()) {
queryParameters.put(entry.getKey(), entry.getValue().get(0));
}
String bodyQueryString = body.getQueryString();
if (bodyQueryString != null && ! bodyQueryString.isEmpty()) {
String[] toks = bodyQueryString.split("&");
for (String tok : toks) {
String[] keyVal = tok.split("=");
queryParameters.put(keyVal[0], keyVal.length == 2 ? keyVal[1] : "");
}
}
return queryParameters;
}
/**
* Applies directives and determines if a query predicate exists or not.
* <p/>
* Depending on the request type (POST, PUT, etc...), retrieves the appropriate set of directives:
* <ul>
* <li><code>POST</code> - {@link org.apache.ambari.server.api.resources.ResourceDefinition#getCreateDirectives()}</li>
* <li><code>PUT</code> - {@link org.apache.ambari.server.api.resources.ResourceDefinition#getUpdateDirectives()}</li>
* </ul>
* <p/>
* Note: Only <code>POST</code> and <code>PUT</code> are supported.
* <p/>
* Iterates through the query parameters adding those that are known to be directives to the map
* of request info properties from {@link RequestBody#getRequestInfoProperties()}.
* <p/>
* If a query property is found that is not a directive, a query predicate exists and
* <code>false</code> is returned; else all query parameters are directives, leaving no query predicate,
* and <code>true</code> is returned.
*
* @return true if all the directives are supported; false if at least one directive is not supported
*/
private boolean applyDirectives(Request.Type requestType, RequestBody body, UriInfo uriInfo, ResourceInstance resource) {
Map<String, String> queryParameters = getQueryParameters(uriInfo, body);
Map<String, String> requestInfoProperties;
boolean allDirectivesApplicable = true;
if (!queryParameters.isEmpty()) {
ResourceDefinition resourceDefinition = resource.getResourceDefinition();
Collection<String> directives;
switch (requestType) {
case PUT:
directives = resourceDefinition.getUpdateDirectives();
break;
case POST:
directives = resourceDefinition.getCreateDirectives();
break;
case GET:
directives = resourceDefinition.getReadDirectives();
break;
case DELETE:
directives = resourceDefinition.getDeleteDirectives();
break;
default:
// not yet implemented for other types
return false;
}
requestInfoProperties = body.getRequestInfoProperties();
for (Map.Entry<String, String> entry : queryParameters.entrySet()) {
if (directives.contains(entry.getKey())) {
requestInfoProperties.put(entry.getKey(), entry.getValue());
}
else {
allDirectivesApplicable = false;
}
}
}
return allDirectivesApplicable;
}
}