Source code

001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.camel.component.rest;
018
019import java.util.Map;
020import java.util.Set;
021
022import org.apache.camel.Component;
023import org.apache.camel.Consumer;
024import org.apache.camel.ExchangePattern;
025import org.apache.camel.NoFactoryAvailableException;
026import org.apache.camel.NoSuchBeanException;
027import org.apache.camel.Processor;
028import org.apache.camel.Producer;
029import org.apache.camel.impl.DefaultEndpoint;
030import org.apache.camel.spi.FactoryFinder;
031import org.apache.camel.spi.Metadata;
032import org.apache.camel.spi.RestApiConsumerFactory;
033import org.apache.camel.spi.RestApiProcessorFactory;
034import org.apache.camel.spi.RestConfiguration;
035import org.apache.camel.spi.UriEndpoint;
036import org.apache.camel.spi.UriParam;
037import org.apache.camel.spi.UriPath;
038import org.apache.camel.util.HostUtils;
039import org.apache.camel.util.ObjectHelper;
040
041/**
042 * The rest-api component is used for providing Swagger API of the REST services which has been defined using the rest-dsl in Camel.
043 */
044@UriEndpoint(firstVersion = "2.16.0", scheme = "rest-api", title = "REST API", syntax = "rest-api:path/contextIdPattern",
045    consumerOnly = true, label = "core,rest", lenientProperties = true)
046public class RestApiEndpoint extends DefaultEndpoint {
047
048    public static final String DEFAULT_API_COMPONENT_NAME = "swagger";
049    public static final String RESOURCE_PATH = "META-INF/services/org/apache/camel/restapi/";
050
051    @UriPath
052    @Metadata(required = "true")
053    private String path;
054    @UriPath
055    private String contextIdPattern;
056    @UriParam
057    private String componentName;
058    @UriParam
059    private String apiComponentName;
060
061    private Map<String, Object> parameters;
062
063    public RestApiEndpoint(String endpointUri, RestApiComponent component) {
064        super(endpointUri, component);
065        setExchangePattern(ExchangePattern.InOut);
066    }
067
068    @Override
069    public RestApiComponent getComponent() {
070        return (RestApiComponent) super.getComponent();
071    }
072
073    public String getPath() {
074        return path;
075    }
076
077    /**
078     * The base path
079     */
080    public void setPath(String path) {
081        this.path = path;
082    }
083
084    public String getContextIdPattern() {
085        return contextIdPattern;
086    }
087
088    /**
089     * Optional CamelContext id pattern to only allow Rest APIs from rest services within CamelContext's which name matches the pattern.
090     */
091    public void setContextIdPattern(String contextIdPattern) {
092        this.contextIdPattern = contextIdPattern;
093    }
094
095    public String getComponentName() {
096        return componentName;
097    }
098
099    /**
100     * The Camel Rest component to use for the REST transport, such as restlet, spark-rest.
101     * If no component has been explicit configured, then Camel will lookup if there is a Camel component
102     * that integrates with the Rest DSL, or if a org.apache.camel.spi.RestConsumerFactory is registered in the registry.
103     * If either one is found, then that is being used.
104     */
105    public void setComponentName(String componentName) {
106        this.componentName = componentName;
107    }
108
109    public String getApiComponentName() {
110        return apiComponentName;
111    }
112
113    /**
114     * The Camel Rest API component to use for generating the API of the REST services, such as swagger.
115     */
116    public void setApiComponentName(String apiComponentName) {
117        this.apiComponentName = apiComponentName;
118    }
119
120    public Map<String, Object> getParameters() {
121        return parameters;
122    }
123
124    /**
125     * Additional parameters to configure the consumer of the REST transport for this REST service
126     */
127    public void setParameters(Map<String, Object> parameters) {
128        this.parameters = parameters;
129    }
130
131    @Override
132    public Producer createProducer() throws Exception {
133        RestApiProcessorFactory factory = null;
134
135        RestConfiguration config = getCamelContext().getRestConfiguration(componentName, true);
136
137        // lookup in registry
138        Set<RestApiProcessorFactory> factories = getCamelContext().getRegistry().findByType(RestApiProcessorFactory.class);
139        if (factories != null && factories.size() == 1) {
140            factory = factories.iterator().next();
141        }
142
143        // lookup on classpath using factory finder to automatic find it (just add camel-swagger-java to classpath etc)
144        if (factory == null) {
145            String name = apiComponentName != null ? apiComponentName : config.getApiComponent();
146            if (name == null) {
147                name = DEFAULT_API_COMPONENT_NAME;
148            }
149            try {
150                FactoryFinder finder = getCamelContext().getFactoryFinder(RESOURCE_PATH);
151                Object instance = finder.newInstance(name);
152                if (instance instanceof RestApiProcessorFactory) {
153                    factory = (RestApiProcessorFactory) instance;
154                }
155            } catch (NoFactoryAvailableException e) {
156                // ignore
157            }
158        }
159
160        if (factory != null) {
161
162            // if no explicit port/host configured, then use port from rest configuration
163            String host = "";
164            int port = 80;
165
166            if (config.getHost() != null) {
167                host = config.getHost();
168            }
169            int num = config.getPort();
170            if (num > 0) {
171                port = num;
172            }
173
174            // if no explicit hostname set then resolve the hostname
175            if (ObjectHelper.isEmpty(host)) {
176                if (config.getRestHostNameResolver() == RestConfiguration.RestHostNameResolver.allLocalIp) {
177                    host = "0.0.0.0";
178                } else if (config.getRestHostNameResolver() == RestConfiguration.RestHostNameResolver.localHostName) {
179                    host = HostUtils.getLocalHostName();
180                } else if (config.getRestHostNameResolver() == RestConfiguration.RestHostNameResolver.localIp) {
181                    host = HostUtils.getLocalIp();
182                }
183
184                // no host was configured so calculate a host to use
185                // there should be no schema in the host (but only port)
186                String targetHost = host + (port != 80 ? ":" + port : "");
187                getParameters().put("host", targetHost);
188            }
189
190            // the base path should start with a leading slash
191            String path = getPath();
192            if (path != null && !path.startsWith("/")) {
193                path = "/" + path;
194            }
195
196            // whether listing of the context id's is enabled or not
197            boolean contextIdListing = config.isApiContextListing();
198
199            Processor processor = factory.createApiProcessor(getCamelContext(), path, getContextIdPattern(), contextIdListing, config, getParameters());
200            return new RestApiProducer(this, processor);
201        } else {
202            throw new IllegalStateException("Cannot find RestApiProcessorFactory in Registry or classpath (such as the camel-swagger-java component)");
203        }
204    }
205
206    @Override
207    public Consumer createConsumer(Processor processor) throws Exception {
208        RestApiConsumerFactory factory = null;
209        String cname = null;
210
211        // we use the rest component as the HTTP consumer to service the API
212        // the API then uses the api component (eg usually camel-swagger-java) to build the API
213        if (getComponentName() != null) {
214            Object comp = getCamelContext().getRegistry().lookupByName(getComponentName());
215            if (comp != null && comp instanceof RestApiConsumerFactory) {
216                factory = (RestApiConsumerFactory) comp;
217            } else {
218                comp = getCamelContext().getComponent(getComponentName());
219                if (comp != null && comp instanceof RestApiConsumerFactory) {
220                    factory = (RestApiConsumerFactory) comp;
221                }
222            }
223
224            if (factory == null) {
225                if (comp != null) {
226                    throw new IllegalArgumentException("Component " + getComponentName() + " is not a RestApiConsumerFactory");
227                } else {
228                    throw new NoSuchBeanException(getComponentName(), RestApiConsumerFactory.class.getName());
229                }
230            }
231            cname = getComponentName();
232        }
233
234        // try all components
235        if (factory == null) {
236            for (String name : getCamelContext().getComponentNames()) {
237                Component comp = getCamelContext().getComponent(name);
238                if (comp != null && comp instanceof RestApiConsumerFactory) {
239                    factory = (RestApiConsumerFactory) comp;
240                    cname = name;
241                    break;
242                }
243            }
244        }
245
246        // lookup in registry
247        if (factory == null) {
248            Set<RestApiConsumerFactory> factories = getCamelContext().getRegistry().findByType(RestApiConsumerFactory.class);
249            if (factories != null && factories.size() == 1) {
250                factory = factories.iterator().next();
251            }
252        }
253
254        if (factory != null) {
255            // calculate the url to the rest API service
256            RestConfiguration config = getCamelContext().getRestConfiguration(cname, true);
257
258            // calculate the url to the rest API service
259            String path = getPath();
260            if (path != null && !path.startsWith("/")) {
261                path = "/" + path;
262            }
263
264            Consumer consumer = factory.createApiConsumer(getCamelContext(), processor, path, config, getParameters());
265            configureConsumer(consumer);
266
267            return consumer;
268        } else {
269            throw new IllegalStateException("Cannot find RestApiConsumerFactory in Registry or as a Component to use");
270        }
271    }
272
273    @Override
274    public boolean isSingleton() {
275        return true;
276    }
277
278    @Override
279    public boolean isLenientProperties() {
280        return true;
281    }
282}