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.getApiHost() != null) {
167                host = config.getApiHost();
168            } else if (config.getHost() != null) {
169                host = config.getHost();
170            }
171            int num = config.getPort();
172            if (num > 0) {
173                port = num;
174            }
175
176            // if no explicit hostname set then resolve the hostname
177            if (ObjectHelper.isEmpty(host)) {
178                if (config.getHostNameResolver() == RestConfiguration.RestHostNameResolver.allLocalIp) {
179                    host = "0.0.0.0";
180                } else if (config.getHostNameResolver() == RestConfiguration.RestHostNameResolver.localHostName) {
181                    host = HostUtils.getLocalHostName();
182                } else if (config.getHostNameResolver() == RestConfiguration.RestHostNameResolver.localIp) {
183                    host = HostUtils.getLocalIp();
184                }
185
186                // no host was configured so calculate a host to use
187                // there should be no schema in the host (but only port)
188                String targetHost = host + (port != 80 ? ":" + port : "");
189                getParameters().put("host", targetHost);
190            }
191
192            // the base path should start with a leading slash
193            String path = getPath();
194            if (path != null && !path.startsWith("/")) {
195                path = "/" + path;
196            }
197
198            // whether listing of the context id's is enabled or not
199            boolean contextIdListing = config.isApiContextListing();
200
201            Processor processor = factory.createApiProcessor(getCamelContext(), path, getContextIdPattern(), contextIdListing, config, getParameters());
202            return new RestApiProducer(this, processor);
203        } else {
204            throw new IllegalStateException("Cannot find RestApiProcessorFactory in Registry or classpath (such as the camel-swagger-java component)");
205        }
206    }
207
208    @Override
209    public Consumer createConsumer(Processor processor) throws Exception {
210        RestApiConsumerFactory factory = null;
211        String cname = null;
212
213        // we use the rest component as the HTTP consumer to service the API
214        // the API then uses the api component (eg usually camel-swagger-java) to build the API
215        if (getComponentName() != null) {
216            Object comp = getCamelContext().getRegistry().lookupByName(getComponentName());
217            if (comp instanceof RestApiConsumerFactory) {
218                factory = (RestApiConsumerFactory) comp;
219            } else {
220                comp = getCamelContext().getComponent(getComponentName());
221                if (comp instanceof RestApiConsumerFactory) {
222                    factory = (RestApiConsumerFactory) comp;
223                }
224            }
225
226            if (factory == null) {
227                if (comp != null) {
228                    throw new IllegalArgumentException("Component " + getComponentName() + " is not a RestApiConsumerFactory");
229                } else {
230                    throw new NoSuchBeanException(getComponentName(), RestApiConsumerFactory.class.getName());
231                }
232            }
233            cname = getComponentName();
234        }
235
236        // try all components
237        if (factory == null) {
238            for (String name : getCamelContext().getComponentNames()) {
239                Component comp = getCamelContext().getComponent(name);
240                if (comp instanceof RestApiConsumerFactory) {
241                    factory = (RestApiConsumerFactory) comp;
242                    cname = name;
243                    break;
244                }
245            }
246        }
247
248        // lookup in registry
249        if (factory == null) {
250            Set<RestApiConsumerFactory> factories = getCamelContext().getRegistry().findByType(RestApiConsumerFactory.class);
251            if (factories != null && factories.size() == 1) {
252                factory = factories.iterator().next();
253            }
254        }
255
256        if (factory != null) {
257            // calculate the url to the rest API service
258            RestConfiguration config = getCamelContext().getRestConfiguration(cname, true);
259
260            // calculate the url to the rest API service
261            String path = getPath();
262            if (path != null && !path.startsWith("/")) {
263                path = "/" + path;
264            }
265
266            Consumer consumer = factory.createApiConsumer(getCamelContext(), processor, path, config, getParameters());
267            configureConsumer(consumer);
268
269            return consumer;
270        } else {
271            throw new IllegalStateException("Cannot find RestApiConsumerFactory in Registry or as a Component to use");
272        }
273    }
274
275    @Override
276    public boolean isSingleton() {
277        return true;
278    }
279
280    @Override
281    public boolean isLenientProperties() {
282        return true;
283    }
284}