Source code

001/*
002 * #%L
003 * HAPI FHIR - Server Framework
004 * %%
005 * Copyright (C) 2014 - 2024 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.ConfigurationException;
023import ca.uhn.fhir.context.FhirContext;
024import ca.uhn.fhir.i18n.Msg;
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.RestfulServer;
037import ca.uhn.fhir.rest.server.SimpleBundleProvider;
038import ca.uhn.fhir.rest.server.exceptions.BaseServerResponseException;
039import ca.uhn.fhir.rest.server.exceptions.MethodNotAllowedException;
040import ca.uhn.fhir.rest.server.servlet.ServletRequestDetails;
041import ca.uhn.fhir.system.HapiSystemProperties;
042import jakarta.annotation.Nonnull;
043import org.hl7.fhir.instance.model.api.IBaseConformance;
044
045import java.lang.reflect.Method;
046import java.util.concurrent.ExecutorService;
047import java.util.concurrent.LinkedBlockingQueue;
048import java.util.concurrent.ThreadFactory;
049import java.util.concurrent.ThreadPoolExecutor;
050import java.util.concurrent.TimeUnit;
051import java.util.concurrent.atomic.AtomicLong;
052import java.util.concurrent.atomic.AtomicReference;
053
054public class ConformanceMethodBinding extends BaseResourceReturningMethodBinding {
055        public static final String CACHE_THREAD_PREFIX = "capabilitystatement-cache-";
056        /*
057         * Note: This caching mechanism should probably be configurable and maybe
058         * even applicable to other bindings. It's particularly important for this
059         * operation though, so a one-off is fine for now
060         */
061        private final AtomicReference<IBaseConformance> myCachedResponse = new AtomicReference<>();
062        private final AtomicLong myCachedResponseExpires = new AtomicLong(0L);
063        private final ExecutorService myThreadPool;
064        private long myCacheMillis = 60 * 1000;
065
066        ConformanceMethodBinding(Method theMethod, FhirContext theContext, Object theProvider) {
067                super(theMethod.getReturnType(), theMethod, theContext, theProvider);
068
069                MethodReturnTypeEnum methodReturnType = getMethodReturnType();
070                Class<?> genericReturnType = (Class<?>) theMethod.getGenericReturnType();
071                if (methodReturnType != MethodReturnTypeEnum.RESOURCE
072                                || !IBaseConformance.class.isAssignableFrom(genericReturnType)) {
073                        throw new ConfigurationException(
074                                        Msg.code(387) + "Conformance resource provider method '" + theMethod.getName()
075                                                        + "' should return a Conformance resource class, returns: " + theMethod.getReturnType());
076                }
077
078                Metadata metadata = theMethod.getAnnotation(Metadata.class);
079                if (metadata != null) {
080                        setCacheMillis(metadata.cacheMillis());
081                }
082
083                ThreadFactory threadFactory = r -> {
084                        Thread t = new Thread(r);
085                        t.setName(CACHE_THREAD_PREFIX + t.getId());
086                        t.setDaemon(false);
087                        return t;
088                };
089                myThreadPool = new ThreadPoolExecutor(
090                                1,
091                                1,
092                                0L,
093                                TimeUnit.MILLISECONDS,
094                                new LinkedBlockingQueue<>(1),
095                                threadFactory,
096                                new ThreadPoolExecutor.DiscardOldestPolicy());
097        }
098
099        /**
100         * Returns the number of milliseconds to cache the generated CapabilityStatement for. Default is one minute, and can be
101         * set to 0 to never cache.
102         *
103         * @see #setCacheMillis(long)
104         * @see Metadata#cacheMillis()
105         * @since 4.1.0
106         */
107        private long getCacheMillis() {
108                return myCacheMillis;
109        }
110
111        /**
112         * Returns the number of milliseconds to cache the generated CapabilityStatement for. Default is one minute, and can be
113         * set to 0 to never cache.
114         *
115         * @see #getCacheMillis()
116         * @see Metadata#cacheMillis()
117         * @since 4.1.0
118         */
119        public void setCacheMillis(long theCacheMillis) {
120                myCacheMillis = theCacheMillis;
121        }
122
123        @Override
124        public ReturnTypeEnum getReturnType() {
125                return ReturnTypeEnum.RESOURCE;
126        }
127
128        @Override
129        public void close() {
130                super.close();
131
132                myThreadPool.shutdown();
133        }
134
135        @Override
136        public IBundleProvider invokeServer(
137                        IRestfulServer<?> theServer, RequestDetails theRequest, Object[] theMethodParams)
138                        throws BaseServerResponseException {
139                IBaseConformance conf;
140
141                CacheControlDirective cacheControlDirective =
142                                new CacheControlDirective().parse(theRequest.getHeaders(Constants.HEADER_CACHE_CONTROL));
143
144                if (cacheControlDirective.isNoCache()) conf = null;
145                else {
146                        conf = myCachedResponse.get();
147                        if (HapiSystemProperties.isTestModeEnabled()) {
148                                conf = null;
149                        }
150                        if (conf != null) {
151                                long expires = myCachedResponseExpires.get();
152                                if (expires < System.currentTimeMillis()) {
153                                        myCachedResponseExpires.set(System.currentTimeMillis() + getCacheMillis());
154                                        myThreadPool.submit(() -> createCapabilityStatement(theRequest, theMethodParams));
155                                }
156                        }
157                }
158                if (conf != null) {
159                        // Handle server action interceptors
160                        RestOperationTypeEnum operationType = getRestOperationType(theRequest);
161                        if (operationType != null) {
162
163                                populateRequestDetailsForInterceptor(theRequest, theMethodParams);
164
165                                // Interceptor hook: SERVER_INCOMING_REQUEST_PRE_HANDLED
166                                if (theRequest.getInterceptorBroadcaster() != null) {
167                                        HookParams preHandledParams = new HookParams();
168                                        preHandledParams.add(RestOperationTypeEnum.class, theRequest.getRestOperationType());
169                                        preHandledParams.add(RequestDetails.class, theRequest);
170                                        preHandledParams.addIfMatchesType(ServletRequestDetails.class, theRequest);
171                                        theRequest
172                                                        .getInterceptorBroadcaster()
173                                                        .callHooks(Pointcut.SERVER_INCOMING_REQUEST_PRE_HANDLED, preHandledParams);
174                                }
175                        }
176                }
177
178                if (conf == null) {
179                        conf = createCapabilityStatement(theRequest, theMethodParams);
180                }
181
182                return new SimpleBundleProvider(conf);
183        }
184
185        private IBaseConformance createCapabilityStatement(RequestDetails theRequest, Object[] theMethodParams) {
186                IBaseConformance conf = (IBaseConformance) invokeServerMethod(theRequest, theMethodParams);
187
188                // Interceptor hook: SERVER_CAPABILITY_STATEMENT_GENERATED
189                if (theRequest.getInterceptorBroadcaster() != null) {
190                        HookParams params = new HookParams();
191                        params.add(IBaseConformance.class, conf);
192                        params.add(RequestDetails.class, theRequest);
193                        params.addIfMatchesType(ServletRequestDetails.class, theRequest);
194                        IBaseConformance outcome = (IBaseConformance) theRequest
195                                        .getInterceptorBroadcaster()
196                                        .callHooksAndReturnObject(Pointcut.SERVER_CAPABILITY_STATEMENT_GENERATED, params);
197                        if (outcome != null) {
198                                conf = outcome;
199                        }
200                }
201
202                if (myCacheMillis > 0) {
203                        myCachedResponse.set(conf);
204                        myCachedResponseExpires.set(System.currentTimeMillis() + getCacheMillis());
205                }
206
207                return conf;
208        }
209
210        @Override
211        public MethodMatchEnum incomingServerRequestMatchesMethod(RequestDetails theRequest) {
212                if (theRequest.getRequestType() == RequestTypeEnum.OPTIONS) {
213                        if (theRequest.getOperation() == null && theRequest.getResourceName() == null) {
214                                return MethodMatchEnum.EXACT;
215                        }
216                }
217
218                if (theRequest.getResourceName() != null) {
219                        return MethodMatchEnum.NONE;
220                }
221
222                if ("metadata".equals(theRequest.getOperation())) {
223                        if (theRequest.getRequestType() == RequestTypeEnum.GET) {
224                                return MethodMatchEnum.EXACT;
225                        }
226                        throw new MethodNotAllowedException(
227                                        Msg.code(388) + "/metadata request must use HTTP GET", RequestTypeEnum.GET);
228                }
229
230                return MethodMatchEnum.NONE;
231        }
232
233        @Nonnull
234        @Override
235        public RestOperationTypeEnum getRestOperationType() {
236                return RestOperationTypeEnum.METADATA;
237        }
238
239        @Override
240        protected BundleTypeEnum getResponseBundleType() {
241                return null;
242        }
243
244        /**
245         * Create and return the server's CapabilityStatement
246         */
247        public IBaseConformance provideCapabilityStatement(RestfulServer theServer, RequestDetails theRequest) {
248                Object[] params = createMethodParams(theRequest);
249                IBundleProvider resultObj = invokeServer(theServer, theRequest, params);
250                return (IBaseConformance) resultObj.getResources(0, 1).get(0);
251        }
252}