001package ca.uhn.fhir.rest.server.method;
002
003/*-
004 * #%L
005 * HAPI FHIR - Server Framework
006 * %%
007 * Copyright (C) 2014 - 2022 Smile CDR, Inc.
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 *
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023import ca.uhn.fhir.context.FhirContext;
024import ca.uhn.fhir.interceptor.api.HookParams;
025import ca.uhn.fhir.interceptor.api.Pointcut;
026import ca.uhn.fhir.rest.annotation.GraphQLQueryBody;
027import ca.uhn.fhir.rest.annotation.GraphQLQueryUrl;
028import ca.uhn.fhir.rest.api.Constants;
029import ca.uhn.fhir.rest.api.RequestTypeEnum;
030import ca.uhn.fhir.rest.api.RestOperationTypeEnum;
031import ca.uhn.fhir.rest.api.server.IRestfulServer;
032import ca.uhn.fhir.rest.api.server.RequestDetails;
033import ca.uhn.fhir.rest.api.server.ResponseDetails;
034import ca.uhn.fhir.rest.param.ParameterUtil;
035import ca.uhn.fhir.rest.server.exceptions.BaseServerResponseException;
036import ca.uhn.fhir.rest.server.servlet.ServletRequestDetails;
037import org.apache.commons.lang3.Validate;
038import org.hl7.fhir.instance.model.api.IBaseResource;
039
040import javax.annotation.Nonnull;
041import javax.servlet.http.HttpServletRequest;
042import javax.servlet.http.HttpServletResponse;
043import java.io.IOException;
044import java.io.Writer;
045import java.lang.reflect.Method;
046import java.util.Collections;
047import java.util.Set;
048
049public class GraphQLMethodBinding extends OperationMethodBinding {
050
051        private final Integer myIdParamIndex;
052        private final Integer myQueryUrlParamIndex;
053        private final Integer myQueryBodyParamIndex;
054        private final RequestTypeEnum myMethodRequestType;
055
056        public GraphQLMethodBinding(Method theMethod, RequestTypeEnum theMethodRequestType, FhirContext theContext, Object theProvider) {
057                super(null, null, theMethod, theContext, theProvider, true, false, Constants.OPERATION_NAME_GRAPHQL, null, null, null, null, true);
058
059                myIdParamIndex = ParameterUtil.findIdParameterIndex(theMethod, theContext);
060                myQueryUrlParamIndex = ParameterUtil.findParamAnnotationIndex(theMethod, GraphQLQueryUrl.class);
061                myQueryBodyParamIndex = ParameterUtil.findParamAnnotationIndex(theMethod, GraphQLQueryBody.class);
062                myMethodRequestType = theMethodRequestType;
063        }
064
065        @Override
066        public String getResourceName() {
067                return null;
068        }
069
070        @Nonnull
071        @Override
072        public RestOperationTypeEnum getRestOperationType() {
073                return RestOperationTypeEnum.GRAPHQL_REQUEST;
074        }
075
076        @Override
077        public RestOperationTypeEnum getRestOperationType(RequestDetails theRequestDetails) {
078                return getRestOperationType();
079        }
080
081        @Override
082        protected Set<Class<?>> provideExpectedReturnTypes() {
083                return Collections.singleton(String.class);
084        }
085
086        @Override
087        public boolean isCanOperateAtServerLevel() {
088                return true;
089        }
090
091        @Override
092        public boolean isCanOperateAtTypeLevel() {
093                return false;
094        }
095
096        @Override
097        public boolean isCanOperateAtInstanceLevel() {
098                return myIdParamIndex != null;
099        }
100
101        @Override
102        public MethodMatchEnum incomingServerRequestMatchesMethod(RequestDetails theRequest) {
103                if (Constants.OPERATION_NAME_GRAPHQL.equals(theRequest.getOperation()) && myMethodRequestType.equals(theRequest.getRequestType())) {
104                        return MethodMatchEnum.EXACT;
105                }
106
107                return MethodMatchEnum.NONE;
108        }
109
110        private String getQueryValue(Object[] methodParams) {
111                switch (myMethodRequestType) {
112                        case POST:
113                                Validate.notNull(myQueryBodyParamIndex, "GraphQL method does not have @" + GraphQLQueryBody.class.getSimpleName() + " parameter");
114                                return (String) methodParams[myQueryBodyParamIndex];
115                        case GET:
116                                Validate.notNull(myQueryUrlParamIndex, "GraphQL method does not have @" + GraphQLQueryUrl.class.getSimpleName() + " parameter");
117                                return (String) methodParams[myQueryUrlParamIndex];
118                }
119                return null;
120        }
121
122        @Override
123        public Object invokeServer(IRestfulServer<?> theServer, RequestDetails theRequest) throws BaseServerResponseException, IOException {
124                Object[] methodParams = createMethodParams(theRequest);
125                if (myIdParamIndex != null) {
126                        methodParams[myIdParamIndex] = theRequest.getId();
127                }
128
129                String responseString = (String) invokeServerMethod(theRequest, methodParams);
130
131                int statusCode = Constants.STATUS_HTTP_200_OK;
132                String statusMessage = Constants.HTTP_STATUS_NAMES.get(statusCode);
133                String contentType = Constants.CT_JSON;
134                String charset = Constants.CHARSET_NAME_UTF8;
135                boolean respondGzip = theRequest.isRespondGzip();
136
137                HttpServletRequest servletRequest = null;
138                HttpServletResponse servletResponse = null;
139                if (theRequest instanceof ServletRequestDetails) {
140                        servletRequest = ((ServletRequestDetails) theRequest).getServletRequest();
141                        servletResponse = ((ServletRequestDetails) theRequest).getServletResponse();
142                }
143
144                String graphQLQuery = getQueryValue(methodParams);
145                // Interceptor call: SERVER_OUTGOING_GRAPHQL_RESPONSE
146                HookParams params = new HookParams()
147                        .add(RequestDetails.class, theRequest)
148                        .addIfMatchesType(ServletRequestDetails.class, theRequest)
149                        .add(String.class, graphQLQuery)
150                        .add(String.class, responseString)
151                        .add(HttpServletRequest.class, servletRequest)
152                        .add(HttpServletResponse.class, servletResponse);
153                if (!theRequest.getInterceptorBroadcaster().callHooks(Pointcut.SERVER_OUTGOING_GRAPHQL_RESPONSE, params)) {
154                        return null;
155                }
156
157                // Interceptor call: SERVER_OUTGOING_RESPONSE
158                params = new HookParams()
159                        .add(RequestDetails.class, theRequest)
160                        .addIfMatchesType(ServletRequestDetails.class, theRequest)
161                        .add(IBaseResource.class, null)
162                        .add(ResponseDetails.class, new ResponseDetails())
163                        .add(HttpServletRequest.class, servletRequest)
164                        .add(HttpServletResponse.class, servletResponse);
165                if (!theRequest.getInterceptorBroadcaster().callHooks(Pointcut.SERVER_OUTGOING_RESPONSE, params)) {
166                        return null;
167                }
168
169                // Write the response
170                Writer writer = theRequest.getResponse().getResponseWriter(statusCode, statusMessage, contentType, charset, respondGzip);
171                writer.write(responseString);
172                writer.close();
173
174                return null;
175        }
176}