001package ca.uhn.fhir.rest.server.method;
002
003/*
004 * #%L
005 * HAPI FHIR - Server Framework
006 * %%
007 * Copyright (C) 2014 - 2019 University Health Network
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.ConfigurationException;
024import ca.uhn.fhir.context.FhirContext;
025import ca.uhn.fhir.interceptor.api.HookParams;
026import ca.uhn.fhir.interceptor.api.Pointcut;
027import ca.uhn.fhir.model.valueset.BundleTypeEnum;
028import ca.uhn.fhir.rest.annotation.Metadata;
029import ca.uhn.fhir.rest.api.CacheControlDirective;
030import ca.uhn.fhir.rest.api.Constants;
031import ca.uhn.fhir.rest.api.RequestTypeEnum;
032import ca.uhn.fhir.rest.api.RestOperationTypeEnum;
033import ca.uhn.fhir.rest.api.server.IBundleProvider;
034import ca.uhn.fhir.rest.api.server.IRestfulServer;
035import ca.uhn.fhir.rest.api.server.RequestDetails;
036import ca.uhn.fhir.rest.server.SimpleBundleProvider;
037import ca.uhn.fhir.rest.server.exceptions.BaseServerResponseException;
038import ca.uhn.fhir.rest.server.exceptions.MethodNotAllowedException;
039import ca.uhn.fhir.rest.server.interceptor.IServerInterceptor;
040import ca.uhn.fhir.rest.server.servlet.ServletRequestDetails;
041import org.hl7.fhir.instance.model.api.IBaseConformance;
042import org.hl7.fhir.instance.model.api.IBaseResource;
043
044import javax.annotation.Nonnull;
045import java.lang.reflect.Method;
046import java.util.concurrent.atomic.AtomicLong;
047import java.util.concurrent.atomic.AtomicReference;
048
049public class ConformanceMethodBinding extends BaseResourceReturningMethodBinding {
050        /*
051         * Note: This caching mechanism should probably be configurable and maybe
052         * even applicable to other bindings. It's particularly important for this
053         * operation though, so a one-off is fine for now
054         */
055        private final AtomicReference<IBaseResource> myCachedResponse = new AtomicReference<>();
056        private final AtomicLong myCachedResponseExpires = new AtomicLong(0L);
057        private long myCacheMillis = 60 * 1000;
058
059        ConformanceMethodBinding(Method theMethod, FhirContext theContext, Object theProvider) {
060                super(theMethod.getReturnType(), theMethod, theContext, theProvider);
061
062                MethodReturnTypeEnum methodReturnType = getMethodReturnType();
063                Class<?> genericReturnType = (Class<?>) theMethod.getGenericReturnType();
064                if (methodReturnType != MethodReturnTypeEnum.RESOURCE || !IBaseConformance.class.isAssignableFrom(genericReturnType)) {
065                        throw new ConfigurationException("Conformance resource provider method '" + theMethod.getName() + "' should return a Conformance resource class, returns: " + theMethod.getReturnType());
066                }
067
068                Metadata metadata = theMethod.getAnnotation(Metadata.class);
069                if (metadata != null) {
070                        setCacheMillis(metadata.cacheMillis());
071                }
072
073        }
074
075        /**
076         * Returns the number of milliseconds to cache the generated CapabilityStatement for. Default is one minute, and can be
077         * set to 0 to never cache.
078         *
079         * @see #setCacheMillis(long)
080         * @see Metadata#cacheMillis()
081         * @since 4.1.0
082         */
083        private long getCacheMillis() {
084                return myCacheMillis;
085        }
086
087        /**
088         * Returns the number of milliseconds to cache the generated CapabilityStatement for. Default is one minute, and can be
089         * set to 0 to never cache.
090         *
091         * @see #getCacheMillis()
092         * @see Metadata#cacheMillis()
093         * @since 4.1.0
094         */
095        private void setCacheMillis(long theCacheMillis) {
096                myCacheMillis = theCacheMillis;
097        }
098
099        @Override
100        public ReturnTypeEnum getReturnType() {
101                return ReturnTypeEnum.RESOURCE;
102        }
103
104        @Override
105        public IBundleProvider invokeServer(IRestfulServer<?> theServer, RequestDetails theRequest, Object[] theMethodParams) throws BaseServerResponseException {
106                IBaseResource conf;
107
108                CacheControlDirective cacheControlDirective = new CacheControlDirective().parse(theRequest.getHeaders(Constants.HEADER_CACHE_CONTROL));
109
110                if (cacheControlDirective.isNoCache())
111                        conf = null;
112                else {
113                        conf = myCachedResponse.get();
114                        if ("true".equals(System.getProperty("test"))) {
115                                conf = null;
116                        }
117                        if (conf != null) {
118                                long expires = myCachedResponseExpires.get();
119                                if (expires < System.currentTimeMillis()) {
120                                        conf = null;
121                                }
122                        }
123                }
124                if (conf != null) {
125                        // Handle server action interceptors
126                        RestOperationTypeEnum operationType = getRestOperationType(theRequest);
127                        if (operationType != null) {
128                                IServerInterceptor.ActionRequestDetails details = new IServerInterceptor.ActionRequestDetails(theRequest);
129                                populateActionRequestDetailsForInterceptor(theRequest, details, theMethodParams);
130                                HookParams preHandledParams = new HookParams();
131                                preHandledParams.add(RestOperationTypeEnum.class, theRequest.getRestOperationType());
132                                preHandledParams.add(RequestDetails.class, theRequest);
133                                preHandledParams.addIfMatchesType(ServletRequestDetails.class, theRequest);
134                                preHandledParams.add(IServerInterceptor.ActionRequestDetails.class, details);
135                                if (theRequest.getInterceptorBroadcaster() != null) {
136                                        theRequest
137                                                .getInterceptorBroadcaster()
138                                                .callHooks(Pointcut.SERVER_INCOMING_REQUEST_PRE_HANDLED, preHandledParams);
139                                }
140                        }
141                }
142
143                if (conf == null) {
144                        conf = (IBaseResource) invokeServerMethod(theServer, theRequest, theMethodParams);
145                        if (myCacheMillis > 0) {
146                                myCachedResponse.set(conf);
147                                myCachedResponseExpires.set(System.currentTimeMillis() + getCacheMillis());
148                        }
149                }
150
151                return new SimpleBundleProvider(conf);
152        }
153
154        @Override
155        public boolean incomingServerRequestMatchesMethod(RequestDetails theRequest) {
156                if (theRequest.getRequestType() == RequestTypeEnum.OPTIONS) {
157                        if (theRequest.getOperation() == null && theRequest.getResourceName() == null) {
158                                return true;
159                        }
160                }
161
162                if (theRequest.getResourceName() != null) {
163                        return false;
164                }
165
166                if ("metadata".equals(theRequest.getOperation())) {
167                        if (theRequest.getRequestType() == RequestTypeEnum.GET) {
168                                return true;
169                        }
170                        throw new MethodNotAllowedException("/metadata request must use HTTP GET", RequestTypeEnum.GET);
171                }
172
173                return false;
174        }
175
176        @Nonnull
177        @Override
178        public RestOperationTypeEnum getRestOperationType() {
179                return RestOperationTypeEnum.METADATA;
180        }
181
182        @Override
183        protected BundleTypeEnum getResponseBundleType() {
184                return null;
185        }
186
187}