org.eclipse.skalli.api/src/main/java/org/eclipse/skalli/services/rest/RequestContext.java - skalli/org.eclipse.skalli - Git at Google

 /*******************************************************************************
  * Copyright (c) 2010-2014 SAP AG and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  *     SAP AG - initial API and implementation
  *******************************************************************************/
 package org.eclipse.skalli.services.rest;

 import java.util.Collections;
 import java.util.Map;
 import java.util.Set;

 import org.apache.commons.lang.StringUtils;
 import org.eclipse.skalli.commons.CollectionUtils;
 import org.restlet.Request;
 import org.restlet.data.Form;
 import org.restlet.data.MediaType;
 import org.restlet.data.Preference;
 import org.restlet.data.Reference;
 import org.restlet.resource.ServerResource;

 /**
  * Helper class providing information about a request for a REST resource
  * like query attributes and request path.
  */
 public class RequestContext {

     private static final String ACCEPT_ALL = "*/*"; //$NON-NLS-1$

     @SuppressWarnings("nls")
     private static final Set<String> FORMAT_JSON =
             CollectionUtils.asSet("json", "text/json", MediaType.APPLICATION_JSON.toString());

     // for backward compatibility and to facilitate browser access,
     // we also accept "html" and "text/html", but treat them as "text/xml"
     @SuppressWarnings("nls")
     private static final Set<String> FORMAT_XML =
             CollectionUtils.asSet(
                     "xml", MediaType.TEXT_XML.toString(), MediaType.APPLICATION_XML.toString(),
                     "html", MediaType.TEXT_HTML.toString());

     private static final String ACCEPT_QUERY_PARAM = "accept"; //$NON-NLS-1$

     private String action;
     private String path;
     private Reference resourceRef;
     private Form form;
     private Form headers;
     private Map<String,String> queryParams;
     private MediaType mediaType;

     /**
      * Creates a request context from a given REST request.
      * <p>
      * Extracts request parameters like {@link #getPath() path} and
      * {@link #getQueryAttributes() query attributes}.
      *
      * @param request  the REST request to evaluate.
      */
     public RequestContext(Request request) {
         action = request.getMethod().getName();
         resourceRef = request.getResourceRef();
         path = resourceRef != null ? resourceRef.getPath() : "/"; //$NON-NLS-1$
         form = resourceRef != null ? resourceRef.getQueryAsForm() : null;
         if (form != null) {
             queryParams = form.getValuesMap();
         } else {
             form = new Form();
             queryParams = Collections.emptyMap();
         }
         mediaType = getMediaType(request);
         headers = (Form) request.getAttributes().get("org.restlet.http.headers"); //$NON-NLS-1$
     }

     /**
      * Creates a request context from a given server resource.
      * <p>
      * This is a convenience method equivalent to
      * {@link #RequestContext(Request) RequestContext(serverResource.getRequest())}.
      *
      * @param serverResource  the server resource to evaluate.
      */
     public RequestContext(ServerResource serverResource) {
         this(serverResource.getRequest());
     }

     /**
      * Returns the request path including the context path
      * prefix <code>/api</code>.
      */
     public String getPath() {
         return path;
     }

     /**
      * Returns the action of this request.
      */
     public String getAction() {
         return action;
     }

     /**
      * Returns the reference of the requested resource, or <code>null</code>
      * if the requested resource could not be determined.
      *
      * @see org.restlet.Request#getResourceRef().
      */
     public Reference getResourceRef() {
         return resourceRef;
     }

     /**
      * Returns the host part of the resource's URL including scheme,
      * host name and port number, or <code>null</code> if the host
      * could not be determined.
      */
     public String getHost() {
         return resourceRef != null ? resourceRef.getHostIdentifier() : null;
     }

     /**
      * Returns the query as form, which may be an {@link Form#Form() empty form}
      * if there is no query.
      */
     public Form getQueryAsForm() {
         return form;
     }

     /**
      * Returns the query as string, which may be an empty string
      * if there is no query.
      */
     public String getQueryString() {
         return form.getQueryString();
     }

     /**
      * Returns the value of a given query attribute.
      *
      * @param name  the name of the attribute.
      *
      * @return  the value of the attribute, which may be
      * <code>null</code> either if there is no attribute
      * with the given name, or the attribute is a boolean
      * attribute.
      */
     public String getQueryAttribute(String name) {
         return queryParams.get(name);
     }

     /**
      * Returns <code>true</code> if there is a query attribute
      * with the given name.
      *
      * @param name  the name of the attribute.
      */
     public boolean hasQueryAttribute(String name) {
         return queryParams.containsKey(name);
     }

     /**
      * Returns the query attributes as map.
      * @return a mapping of attribute names to their respective values,
      * or an empty map if there is no query.
      */
     public Map<String,String> getQueryAttributes() {
         return queryParams;
     }

     /**
      * Returns the value of the header matching the given name
      * (ignoring the case). If there are multiple headers with
      * the same name, only the first one is matched. If there
      * is no matching header, the given default value is returned.
      *
      * @param name  the header name.
      * @param defaultValue  the default value to return in case
      * there is no matching header.
      */
     public String getHeader(String name, String defaultValue) {
         return headers.getFirstValue(name, true, defaultValue);
     }

     /**
      * Returns the requested media type, never <code>null</code>.
      * If no media type can be determined from the request, <tt>"text/xml"</tt>
      * is returned.
      */
     public MediaType getMediaType() {
         return mediaType;
     }

     /**
      * Returns <code>true</code> if the media type is <tt>text/xml</tt>.
      */
     public boolean isXML() {
         return MediaType.TEXT_XML.equals(mediaType);
     }

     /**
      * Returns <code>true</code> if the media type is <tt>application/json</tt>.
      */
     public boolean isJSON() {
         return MediaType.APPLICATION_JSON.equals(mediaType);
     }

     private MediaType getMediaType(Request request) {
         MediaType mediaType = null;
         if (request.isEntityAvailable()) {
             mediaType = request.getEntity().getMediaType();
         }
         if (mediaType == null) {
             String accept = getQueryAttribute(ACCEPT_QUERY_PARAM);
             if (StringUtils.isBlank(accept)) {
                 accept = getMaxQualityAccept(request);
             }
             if (StringUtils.isNotBlank(accept)) {
                 if  (FORMAT_XML.contains(accept)) {
                     mediaType = MediaType.TEXT_XML;
                 } else if (FORMAT_JSON.contains(accept)) {
                     mediaType = MediaType.APPLICATION_JSON;
                 } else if (ACCEPT_ALL.equals(accept)) {
                     mediaType = MediaType.TEXT_XML;
                 } else {
                     mediaType = MediaType.valueOf(accept);
                 }
             }
             if (mediaType == null) {
                 mediaType = MediaType.TEXT_XML;
             }
         }
         return mediaType;
     }

     /**
      * Scans the <tt>Accept</tt> header for the media type with the highest <tt>"q"</tt> attribute.
      * If the list of accepted media type contains {@value #ACCEPT_ALL}, {@value #ACCEPT_ALL} is returned.
      */
     private String getMaxQualityAccept(Request request) {
         String maxQualityAccept = null;
         float maxQuality = 0;
         for (Preference<MediaType> acceptedMediaType: request.getClientInfo().getAcceptedMediaTypes()) {
             String mediaType = acceptedMediaType.getMetadata().getName();
             if (ACCEPT_ALL.equals(mediaType)) {
                 return ACCEPT_ALL;
             }
             float quality = acceptedMediaType.getQuality();
             if (quality > maxQuality) {
                 maxQualityAccept = mediaType;
                 maxQuality = quality;
             }
         }
         return maxQualityAccept;
     }
 }
	/*******************************************************************************
	* Copyright (c) 2010-2014 SAP AG and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v1.0
	* which accompanies this distribution, and is available at
	* http://www.eclipse.org/legal/epl-v10.html
	*
	* Contributors:
	* SAP AG - initial API and implementation
	*******************************************************************************/
	package org.eclipse.skalli.services.rest;

	import java.util.Collections;
	import java.util.Map;
	import java.util.Set;

	import org.apache.commons.lang.StringUtils;
	import org.eclipse.skalli.commons.CollectionUtils;
	import org.restlet.Request;
	import org.restlet.data.Form;
	import org.restlet.data.MediaType;
	import org.restlet.data.Preference;
	import org.restlet.data.Reference;
	import org.restlet.resource.ServerResource;

	/**
	* Helper class providing information about a request for a REST resource
	* like query attributes and request path.
	*/
	public class RequestContext {

	private static final String ACCEPT_ALL = "/"; //$NON-NLS-1$

	@SuppressWarnings("nls")
	private static final Set<String> FORMAT_JSON =
	CollectionUtils.asSet("json", "text/json", MediaType.APPLICATION_JSON.toString());

	// for backward compatibility and to facilitate browser access,
	// we also accept "html" and "text/html", but treat them as "text/xml"
	@SuppressWarnings("nls")
	private static final Set<String> FORMAT_XML =
	CollectionUtils.asSet(
	"xml", MediaType.TEXT_XML.toString(), MediaType.APPLICATION_XML.toString(),
	"html", MediaType.TEXT_HTML.toString());

	private static final String ACCEPT_QUERY_PARAM = "accept"; //$NON-NLS-1$

	private String action;
	private String path;
	private Reference resourceRef;
	private Form form;
	private Form headers;
	private Map<String,String> queryParams;
	private MediaType mediaType;

	/**
	* Creates a request context from a given REST request.
	* <p>
	* Extracts request parameters like {@link #getPath() path} and
	* {@link #getQueryAttributes() query attributes}.
	*
	* @param request the REST request to evaluate.
	*/
	public RequestContext(Request request) {
	action = request.getMethod().getName();
	resourceRef = request.getResourceRef();
	path = resourceRef != null ? resourceRef.getPath() : "/"; //$NON-NLS-1$
	form = resourceRef != null ? resourceRef.getQueryAsForm() : null;
	if (form != null) {
	queryParams = form.getValuesMap();
	} else {
	form = new Form();
	queryParams = Collections.emptyMap();
	}
	mediaType = getMediaType(request);
	headers = (Form) request.getAttributes().get("org.restlet.http.headers"); //$NON-NLS-1$
	}

	/**
	* Creates a request context from a given server resource.
	* <p>
	* This is a convenience method equivalent to
	* {@link #RequestContext(Request) RequestContext(serverResource.getRequest())}.
	*
	* @param serverResource the server resource to evaluate.
	*/
	public RequestContext(ServerResource serverResource) {
	this(serverResource.getRequest());
	}

	/**
	* Returns the request path including the context path
	* prefix <code>/api</code>.
	*/
	public String getPath() {
	return path;
	}

	/**
	* Returns the action of this request.
	*/
	public String getAction() {
	return action;
	}

	/**
	* Returns the reference of the requested resource, or <code>null</code>
	* if the requested resource could not be determined.
	*
	* @see org.restlet.Request#getResourceRef().
	*/
	public Reference getResourceRef() {
	return resourceRef;
	}

	/**
	* Returns the host part of the resource's URL including scheme,
	* host name and port number, or <code>null</code> if the host
	* could not be determined.
	*/
	public String getHost() {
	return resourceRef != null ? resourceRef.getHostIdentifier() : null;
	}

	/**
	* Returns the query as form, which may be an {@link Form#Form() empty form}
	* if there is no query.
	*/
	public Form getQueryAsForm() {
	return form;
	}

	/**
	* Returns the query as string, which may be an empty string
	* if there is no query.
	*/
	public String getQueryString() {
	return form.getQueryString();
	}

	/**
	* Returns the value of a given query attribute.
	*
	* @param name the name of the attribute.
	*
	* @return the value of the attribute, which may be
	* <code>null</code> either if there is no attribute
	* with the given name, or the attribute is a boolean
	* attribute.
	*/
	public String getQueryAttribute(String name) {
	return queryParams.get(name);
	}

	/**
	* Returns <code>true</code> if there is a query attribute
	* with the given name.
	*
	* @param name the name of the attribute.
	*/
	public boolean hasQueryAttribute(String name) {
	return queryParams.containsKey(name);
	}

	/**
	* Returns the query attributes as map.
	* @return a mapping of attribute names to their respective values,
	* or an empty map if there is no query.
	*/
	public Map<String,String> getQueryAttributes() {
	return queryParams;
	}

	/**
	* Returns the value of the header matching the given name
	* (ignoring the case). If there are multiple headers with
	* the same name, only the first one is matched. If there
	* is no matching header, the given default value is returned.
	*
	* @param name the header name.
	* @param defaultValue the default value to return in case
	* there is no matching header.
	*/
	public String getHeader(String name, String defaultValue) {
	return headers.getFirstValue(name, true, defaultValue);
	}

	/**
	* Returns the requested media type, never <code>null</code>.
	* If no media type can be determined from the request, <tt>"text/xml"</tt>
	* is returned.
	*/
	public MediaType getMediaType() {
	return mediaType;
	}

	/**
	* Returns <code>true</code> if the media type is <tt>text/xml</tt>.
	*/
	public boolean isXML() {
	return MediaType.TEXT_XML.equals(mediaType);
	}

	/**
	* Returns <code>true</code> if the media type is <tt>application/json</tt>.
	*/
	public boolean isJSON() {
	return MediaType.APPLICATION_JSON.equals(mediaType);
	}

	private MediaType getMediaType(Request request) {
	MediaType mediaType = null;
	if (request.isEntityAvailable()) {
	mediaType = request.getEntity().getMediaType();
	}
	if (mediaType == null) {
	String accept = getQueryAttribute(ACCEPT_QUERY_PARAM);
	if (StringUtils.isBlank(accept)) {
	accept = getMaxQualityAccept(request);
	}
	if (StringUtils.isNotBlank(accept)) {
	if (FORMAT_XML.contains(accept)) {
	mediaType = MediaType.TEXT_XML;
	} else if (FORMAT_JSON.contains(accept)) {
	mediaType = MediaType.APPLICATION_JSON;
	} else if (ACCEPT_ALL.equals(accept)) {
	mediaType = MediaType.TEXT_XML;
	} else {
	mediaType = MediaType.valueOf(accept);
	}
	}
	if (mediaType == null) {
	mediaType = MediaType.TEXT_XML;
	}
	}
	return mediaType;
	}

	/**
	* Scans the <tt>Accept</tt> header for the media type with the highest <tt>"q"</tt> attribute.
	* If the list of accepted media type contains {@value #ACCEPT_ALL}, {@value #ACCEPT_ALL} is returned.
	*/
	private String getMaxQualityAccept(Request request) {
	String maxQualityAccept = null;
	float maxQuality = 0;
	for (Preference<MediaType> acceptedMediaType: request.getClientInfo().getAcceptedMediaTypes()) {
	String mediaType = acceptedMediaType.getMetadata().getName();
	if (ACCEPT_ALL.equals(mediaType)) {
	return ACCEPT_ALL;
	}
	float quality = acceptedMediaType.getQuality();
	if (quality > maxQuality) {
	maxQualityAccept = mediaType;
	maxQuality = quality;
	}
	}
	return maxQualityAccept;
	}
	}