001/*-
002 * #%L
003 * HAPI FHIR - Server Framework
004 * %%
005 * Copyright (C) 2014 - 2025 Smile CDR, Inc.
006 * %%
007 * Licensed under the Apache License, Version 2.0 (the "License");
008 * you may not use this file except in compliance with the License.
009 * You may obtain a copy of the License at
010 *
011 *      http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 * #L%
019 */
020package ca.uhn.fhir.rest.server.method;
021
022import ca.uhn.fhir.context.FhirContext;
023import ca.uhn.fhir.interceptor.api.HookParams;
024import ca.uhn.fhir.interceptor.api.Pointcut;
025import ca.uhn.fhir.rest.annotation.GraphQLQueryBody;
026import ca.uhn.fhir.rest.annotation.GraphQLQueryUrl;
027import ca.uhn.fhir.rest.api.Constants;
028import ca.uhn.fhir.rest.api.RequestTypeEnum;
029import ca.uhn.fhir.rest.api.RestOperationTypeEnum;
030import ca.uhn.fhir.rest.api.server.IRestfulServer;
031import ca.uhn.fhir.rest.api.server.RequestDetails;
032import ca.uhn.fhir.rest.api.server.ResponseDetails;
033import ca.uhn.fhir.rest.param.ParameterUtil;
034import ca.uhn.fhir.rest.server.exceptions.BaseServerResponseException;
035import ca.uhn.fhir.rest.server.servlet.ServletRequestDetails;
036import jakarta.annotation.Nonnull;
037import jakarta.servlet.http.HttpServletRequest;
038import jakarta.servlet.http.HttpServletResponse;
039import org.apache.commons.lang3.Validate;
040import org.hl7.fhir.instance.model.api.IBaseResource;
041
042import java.io.IOException;
043import java.io.Writer;
044import java.lang.reflect.Method;
045import java.util.Collections;
046import java.util.Set;
047
048public class GraphQLMethodBinding extends OperationMethodBinding {
049
050        private final Integer myIdParamIndex;
051        private final Integer myQueryUrlParamIndex;
052        private final Integer myQueryBodyParamIndex;
053        private final RequestTypeEnum myMethodRequestType;
054
055        public GraphQLMethodBinding(
056                        Method theMethod, RequestTypeEnum theMethodRequestType, FhirContext theContext, Object theProvider) {
057                super(
058                                null,
059                                null,
060                                theMethod,
061                                theContext,
062                                theProvider,
063                                true,
064                                false,
065                                Constants.OPERATION_NAME_GRAPHQL,
066                                null,
067                                null,
068                                null,
069                                null,
070                                true);
071
072                myIdParamIndex = ParameterUtil.findIdParameterIndex(theMethod, theContext);
073                myQueryUrlParamIndex = ParameterUtil.findParamAnnotationIndex(theMethod, GraphQLQueryUrl.class);
074                myQueryBodyParamIndex = ParameterUtil.findParamAnnotationIndex(theMethod, GraphQLQueryBody.class);
075                myMethodRequestType = theMethodRequestType;
076        }
077
078        @Override
079        public String getResourceName() {
080                return null;
081        }
082
083        @Nonnull
084        @Override
085        public RestOperationTypeEnum getRestOperationType() {
086                return RestOperationTypeEnum.GRAPHQL_REQUEST;
087        }
088
089        @Override
090        public RestOperationTypeEnum getRestOperationType(RequestDetails theRequestDetails) {
091                return getRestOperationType();
092        }
093
094        @Override
095        protected Set<Class<?>> provideExpectedReturnTypes() {
096                return Collections.singleton(String.class);
097        }
098
099        @Override
100        public boolean isCanOperateAtServerLevel() {
101                return true;
102        }
103
104        @Override
105        public boolean isCanOperateAtTypeLevel() {
106                return false;
107        }
108
109        @Override
110        public boolean isCanOperateAtInstanceLevel() {
111                return myIdParamIndex != null;
112        }
113
114        @Override
115        public MethodMatchEnum incomingServerRequestMatchesMethod(RequestDetails theRequest) {
116                if (Constants.OPERATION_NAME_GRAPHQL.equals(theRequest.getOperation())
117                                && myMethodRequestType.equals(theRequest.getRequestType())) {
118                        return MethodMatchEnum.EXACT;
119                }
120
121                return MethodMatchEnum.NONE;
122        }
123
124        private String getQueryValue(Object[] methodParams) {
125                switch (myMethodRequestType) {
126                        case POST:
127                                Validate.notNull(
128                                                myQueryBodyParamIndex,
129                                                "GraphQL method does not have @" + GraphQLQueryBody.class.getSimpleName() + " parameter");
130                                return (String) methodParams[myQueryBodyParamIndex];
131                        case GET:
132                                Validate.notNull(
133                                                myQueryUrlParamIndex,
134                                                "GraphQL method does not have @" + GraphQLQueryUrl.class.getSimpleName() + " parameter");
135                                return (String) methodParams[myQueryUrlParamIndex];
136                }
137                return null;
138        }
139
140        @Override
141        public Object invokeServer(IRestfulServer<?> theServer, RequestDetails theRequest)
142                        throws BaseServerResponseException, IOException {
143                Object[] methodParams = createMethodParams(theRequest);
144                if (myIdParamIndex != null) {
145                        methodParams[myIdParamIndex] = theRequest.getId();
146                }
147
148                String responseString = (String) invokeServerMethod(theRequest, methodParams);
149
150                int statusCode = Constants.STATUS_HTTP_200_OK;
151                String statusMessage = Constants.HTTP_STATUS_NAMES.get(statusCode);
152                String contentType = Constants.CT_JSON;
153                String charset = Constants.CHARSET_NAME_UTF8;
154                boolean respondGzip = theRequest.isRespondGzip();
155
156                HttpServletRequest servletRequest = null;
157                HttpServletResponse servletResponse = null;
158                if (theRequest instanceof ServletRequestDetails) {
159                        servletRequest = ((ServletRequestDetails) theRequest).getServletRequest();
160                        servletResponse = ((ServletRequestDetails) theRequest).getServletResponse();
161                }
162
163                String graphQLQuery = getQueryValue(methodParams);
164                // Interceptor call: SERVER_OUTGOING_GRAPHQL_RESPONSE
165                HookParams params = new HookParams()
166                                .add(RequestDetails.class, theRequest)
167                                .addIfMatchesType(ServletRequestDetails.class, theRequest)
168                                .add(String.class, graphQLQuery)
169                                .add(String.class, responseString)
170                                .add(HttpServletRequest.class, servletRequest)
171                                .add(HttpServletResponse.class, servletResponse);
172                if (!theRequest.getInterceptorBroadcaster().callHooks(Pointcut.SERVER_OUTGOING_GRAPHQL_RESPONSE, params)) {
173                        return null;
174                }
175
176                // Interceptor call: SERVER_OUTGOING_RESPONSE
177                params = new HookParams()
178                                .add(RequestDetails.class, theRequest)
179                                .addIfMatchesType(ServletRequestDetails.class, theRequest)
180                                .add(IBaseResource.class, null)
181                                .add(ResponseDetails.class, new ResponseDetails())
182                                .add(HttpServletRequest.class, servletRequest)
183                                .add(HttpServletResponse.class, servletResponse);
184                if (!theRequest.getInterceptorBroadcaster().callHooks(Pointcut.SERVER_OUTGOING_RESPONSE, params)) {
185                        return null;
186                }
187
188                // Write the response
189                Writer writer = theRequest.getResponse().getResponseWriter(statusCode, contentType, charset, respondGzip);
190                writer.write(responseString);
191                writer.close();
192
193                return null;
194        }
195}