001/*
002 * nimbus-jose-jwt
003 *
004 * Copyright 2012-2022, Connect2id Ltd.
005 *
006 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use
007 * this file except in compliance with the License. You may obtain a copy of the
008 * License at
009 *
010 *    http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software distributed
013 * under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
014 * CONDITIONS OF ANY KIND, either express or implied. See the License for the
015 * specific language governing permissions and limitations under the License.
016 */
017
018package com.nimbusds.jose.jwk.source;
019
020
021import java.io.IOException;
022import java.net.URL;
023import java.util.Objects;
024
025import net.jcip.annotations.ThreadSafe;
026
027import com.nimbusds.jose.KeySourceException;
028import com.nimbusds.jose.jwk.JWKSet;
029import com.nimbusds.jose.proc.SecurityContext;
030import com.nimbusds.jose.util.Resource;
031import com.nimbusds.jose.util.ResourceRetriever;
032
033
034/**
035 * JWK set source that loads the keys from a {@link URL}, without health status
036 * reporting.
037 *
038 * @author Thomas Rørvik Skjølberg
039 * @author Vladimir Dzhuvinov
040 * @version 2025-04-03
041 */
042@ThreadSafe
043public class URLBasedJWKSetSource<C extends SecurityContext> implements JWKSetSource<C> {
044        
045        private final URL url;
046        private final ResourceRetriever resourceRetriever;
047
048        
049        /**
050         * Creates a new URL based JWK set source.
051         *
052         * @param url               The JWK set URL. Must not be {@code null}.
053         * @param resourceRetriever The resource retriever to use. Must not
054         *                          be {@code null}.
055         */
056        public URLBasedJWKSetSource(final URL url, final ResourceRetriever resourceRetriever) {
057                Objects.requireNonNull(url, "The URL must not be null");
058                this.url = url;
059                Objects.requireNonNull(resourceRetriever, "The resource retriever must not be null");
060                this.resourceRetriever = resourceRetriever;
061        }
062
063
064        /**
065         * Returns the JWK set URL.
066         *
067         * @return The JWK set URL.
068         */
069        public URL getJWKSetURL() {
070                return url;
071        }
072
073
074        /**
075         * Returns the HTTP resource retriever.
076         *
077         * @return The HTTP resource retriever.
078         */
079        public ResourceRetriever getResourceRetriever() {
080
081                return resourceRetriever;
082        }
083
084
085        @Override
086        public JWKSet getJWKSet(final JWKSetCacheRefreshEvaluator refreshEvaluator, final long currentTime, final C context) throws KeySourceException {
087                
088                Resource resource;
089                try {
090                        resource = getResourceRetriever().retrieveResource(getJWKSetURL());
091                } catch (IOException e) {
092                        throw new JWKSetRetrievalException("Couldn't retrieve JWK set from URL: " + e.getMessage(), e);
093                }
094                
095                try {
096                        // Note on error handling: We want to avoid any generic HTML document
097                        // (i.e. default HTTP error pages) and other invalid responses being accepted
098                        // as an empty list of JWKs. This is handled by the underlying parser;
099                        // it checks that the transferred document is in fact a JSON document,
100                        // and that the "keys" field is present.
101                        return JWKSet.parse(resource.getContent());
102                        
103                } catch (Exception e) {
104                        // Guard against unexpected exceptions
105                        throw new JWKSetParseException("Unable to parse JWK set", e);
106                }
107        }
108        
109        
110        @Override
111        public void close() throws IOException {
112                // do nothing
113        }
114}