Package org.fcrepo.http.api

Class ContentExposingResource

java.lang.Object

org.fcrepo.http.commons.AbstractResource

org.fcrepo.http.api.FedoraBaseResource

org.fcrepo.http.api.ContentExposingResource

Direct Known Subclasses:

FedoraAcl, FedoraFixity, FedoraLdp, FedoraTombstones, FedoraVersioning

public abstract class ContentExposingResource
extends FedoraBaseResource

An abstract class that sits between AbstractResource and any resource that wishes to share the routines for building responses containing binary content.

Author:

Mike Durbin, ajs6f

Field Summary

Fields

Modifier and Type	Field	Description
static String	ACCEPT_DATETIME
protected javax.servlet.ServletContext	context
protected CreateResourceService	createResourceService
protected DeleteResourceService	deleteResourceService
protected EtagService	etagService
protected ExternalContentHandlerFactory	extContentHandlerFactory
protected HttpRdfService	httpRdfService
protected RdfNamespaceRegistry	namespaceRegistry
protected MultiPrefer	prefer
protected ReplacePropertiesService	replacePropertiesService
protected javax.ws.rs.core.Request	request
protected ResourceTripleService	resourceTripleService
protected static com.google.common.base.Splitter.MapSplitter	RFC3230_SPLITTER
protected javax.servlet.http.HttpServletResponse	servletResponse
protected UpdatePropertiesService	updatePropertiesService

Fields inherited from class org.fcrepo.http.api.FedoraBaseResource

dbTransactionExecutor, identifierConverter, resourceFactory, resourceHelper, securityContext, servletRequest, txManager

Fields inherited from class org.fcrepo.http.commons.AbstractResource

defaultPidMinter, fedoraPropsConfig, headers, pidMinter, uriInfo, versionService

Constructor Summary

Constructors

Constructor	Description
ContentExposingResource()

Method Summary

Modifier and Type	Method	Description
protected void	addCacheControlHeaders(javax.servlet.http.HttpServletResponse servletResponse, FedoraResource resource, Transaction transaction)	Add ETag and Last-Modified cache control headers to the response
protected void	addExternalContentHeaders(FedoraResource resource)
protected void	addLinkAndOptionsHttpHeaders(FedoraResource resource)	Add Link and Option headers
protected void	addResourceHttpHeaders(FedoraResource resource)	Add any resource-specific headers to the response
protected void	addTransactionHeaders(FedoraResource resource)
protected org.apache.jena.graph.Node	asNode(FedoraResource resource)	This is a helper method for using the idTranslator to convert this resource into an associated Jena Node.
protected static String	buildLink(String linkUri, String relation)	Utility function for building a Link.
protected void	checkCacheControlHeaders(javax.ws.rs.core.Request request, javax.servlet.http.HttpServletResponse servletResponse, FedoraResource resource, Transaction transaction)	Evaluate the cache control headers for the request to see if it can be served from the cache.
protected void	checkForInsufficientStorageException(Throwable rootThrowable, Throwable throwable)
protected static URI	checksumURI(String checksum)	Create a checksum URI object.
protected javax.ws.rs.core.Response	createUpdateResponse(FedoraResource resource, boolean created)	Create the appropriate response after a create or update request is processed.
protected void	evaluateRequestPreconditions(javax.ws.rs.core.Request request, javax.servlet.http.HttpServletResponse servletResponse, FedoraResource resource, Transaction transaction)	Evaluate request preconditions to ensure the resource is the expected state
protected abstract String	externalPath()
protected javax.ws.rs.core.Response	getBinaryContent(String rangeValue, FedoraResource resource)	Get the binary content of a datastream
protected javax.ws.rs.core.MediaType	getBinaryResourceMediaType(FedoraResource resource)	This method returns a MediaType for a binary resource.
protected int	getChildrenLimit()	Calculate the max number of children to display at once.
protected javax.ws.rs.core.Response	getContent(int limit, FedoraResource resource)	This method returns an HTTP response with content body appropriate to the following arguments.
protected RdfStream	getResourceTriples(FedoraResource resource)
protected static String	getSimpleContentType(javax.ws.rs.core.MediaType requestContentType)
protected URI	getUri(FedoraResource resource)
protected boolean	hasLenientPreferHeader()	Utility to check if the Prefer header contains handling="lenient"
protected static void	hasRestrictedPath(String externalPath)	Check if a path has a segment prefixed with fcr: that is not fcr:metadata or fcr:acl
protected static boolean	isRdfContentType(String contentTypeString)
protected static Collection<URI>	parseDigestHeader(String digest)	Parse the RFC-3230 Digest response header value.
protected void	patchResourcewithSparql(FedoraResource resource, String requestBody)
protected FedoraResource	reloadResource()
protected FedoraResource	resource()
protected void	setVaryAndPreferenceAppliedHeaders(javax.servlet.http.HttpServletResponse servletResponse, MultiPrefer prefer, FedoraResource resource)
protected List<String>	unpackLinks(List<String> rawLinks)	Multi-value Link header values parsed by the javax.ws.rs.core are not split out by the framework Therefore we must do this ourselves.

Methods inherited from class org.fcrepo.http.api.FedoraBaseResource

doesResourceExist, doInDbTx, doInDbTxWithRetry, getFedoraResource, getUserPrincipal, identifierConverter, isGhostNode, transaction

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ACCEPT_DATETIME

public static final String ACCEPT_DATETIME

See Also:

Constant Field Values

request

@Context
protected javax.ws.rs.core.Request request

servletResponse

@Context
protected javax.servlet.http.HttpServletResponse servletResponse

context

@Context
protected javax.servlet.ServletContext context

prefer

@BeanParam
protected MultiPrefer prefer

extContentHandlerFactory

@Inject
protected ExternalContentHandlerFactory extContentHandlerFactory

namespaceRegistry

@Inject
protected RdfNamespaceRegistry namespaceRegistry

createResourceService

@Inject
protected CreateResourceService createResourceService

deleteResourceService

@Inject
protected DeleteResourceService deleteResourceService

replacePropertiesService

@Inject
protected ReplacePropertiesService replacePropertiesService

updatePropertiesService

@Inject
protected UpdatePropertiesService updatePropertiesService

etagService

@Inject
protected EtagService etagService

httpRdfService

@Inject
protected HttpRdfService httpRdfService

resourceTripleService

@Inject
protected ResourceTripleService resourceTripleService

RFC3230_SPLITTER

protected static final com.google.common.base.Splitter.MapSplitter RFC3230_SPLITTER

Constructor Detail

ContentExposingResource

public ContentExposingResource()

Method Detail

externalPath

protected abstract String externalPath()

getContent

protected javax.ws.rs.core.Response getContent(int limit,
                                               FedoraResource resource)
                                        throws IOException

This method returns an HTTP response with content body appropriate to the following arguments.

Parameters:

limit - is the number of child resources returned in the response, -1 for all

resource - the fedora resource

Returns:

HTTP response

Throws:

IOException - in case of error extracting content

setVaryAndPreferenceAppliedHeaders

protected void setVaryAndPreferenceAppliedHeaders(javax.servlet.http.HttpServletResponse servletResponse,
                                                  MultiPrefer prefer,
                                                  FedoraResource resource)

hasLenientPreferHeader

protected boolean hasLenientPreferHeader()

Utility to check if the Prefer header contains handling="lenient"

Returns:

True if handling="lenient" was sent.

getResourceTriples

protected RdfStream getResourceTriples(FedoraResource resource)

getBinaryContent

protected javax.ws.rs.core.Response getBinaryContent(String rangeValue,
                                                     FedoraResource resource)
                                              throws IOException

Get the binary content of a datastream

Parameters:

rangeValue - the range value

resource - the fedora resource

Returns:

Binary blob

Throws:

IOException - if io exception occurred

getUri

protected URI getUri(FedoraResource resource)

resource

protected FedoraResource resource()

reloadResource

protected FedoraResource reloadResource()

addExternalContentHeaders

protected void addExternalContentHeaders(FedoraResource resource)

addLinkAndOptionsHttpHeaders

protected void addLinkAndOptionsHttpHeaders(FedoraResource resource)

Add Link and Option headers

Parameters:

resource - the resource to generate headers for

addTransactionHeaders

protected void addTransactionHeaders(FedoraResource resource)

buildLink

protected static String buildLink(String linkUri,
                                  String relation)

Utility function for building a Link.

Parameters:

linkUri - String of URI for the link.

relation - the relation string.

Returns:

the string version of the link.

unpackLinks

protected List<String> unpackLinks(List<String> rawLinks)

Multi-value Link header values parsed by the javax.ws.rs.core are not split out by the framework Therefore we must do this ourselves.

Parameters:

rawLinks - the list of unprocessed links

Returns:

List of strings containing one link value per string.

addResourceHttpHeaders

protected void addResourceHttpHeaders(FedoraResource resource)

Add any resource-specific headers to the response

Parameters:

resource - the resource

checkCacheControlHeaders

protected void checkCacheControlHeaders(javax.ws.rs.core.Request request,
                                        javax.servlet.http.HttpServletResponse servletResponse,
                                        FedoraResource resource,
                                        Transaction transaction)

Evaluate the cache control headers for the request to see if it can be served from the cache.

Parameters:

request - the request

servletResponse - the servlet response

resource - the fedora resource

transaction - the transaction

addCacheControlHeaders

protected void addCacheControlHeaders(javax.servlet.http.HttpServletResponse servletResponse,
                                      FedoraResource resource,
                                      Transaction transaction)

Add ETag and Last-Modified cache control headers to the response

Note: In this implementation, the HTTP headers for ETags and Last-Modified dates are swapped for fedora:Binary resources and their descriptions. Here, we are drawing a distinction between the HTTP resource and the LDP resource. As an HTTP resource, the last-modified header should reflect when the resource at the given URL was last changed. With fedora:Binary resources and their descriptions, this is a little complicated, for the descriptions have, as their subjects, the binary itself. And the fedora:lastModified property produced by that NonRdfSourceDescription refers to the last-modified date of the binary -- not the last-modified date of the NonRdfSourceDescription.

Parameters:

servletResponse - the servlet response

resource - the fedora resource

transaction - the transaction

evaluateRequestPreconditions

protected void evaluateRequestPreconditions(javax.ws.rs.core.Request request,
                                            javax.servlet.http.HttpServletResponse servletResponse,
                                            FedoraResource resource,
                                            Transaction transaction)

Evaluate request preconditions to ensure the resource is the expected state

Parameters:

request - the request

servletResponse - the servlet response

resource - the resource

transaction - the transaction

createUpdateResponse

protected javax.ws.rs.core.Response createUpdateResponse(FedoraResource resource,
                                                         boolean created)

Create the appropriate response after a create or update request is processed. When a resource is created, examine the Prefer and Accept headers to determine whether to include a representation. By default, the URI for the created resource is return as plain text. If a minimal response is requested, then no body is returned. If a non-minimal return is requested, return the RDF for the created resource in the appropriate RDF serialization.

Parameters:

resource - The created or updated Fedora resource.

created - True for a newly-created resource, false for an updated resource.

Returns:

204 No Content (for updated resources), 201 Created (for created resources) including the resource URI or content depending on Prefer headers.

getSimpleContentType

protected static String getSimpleContentType(javax.ws.rs.core.MediaType requestContentType)

isRdfContentType

protected static boolean isRdfContentType(String contentTypeString)

patchResourcewithSparql

protected void patchResourcewithSparql(FedoraResource resource,
                                       String requestBody)

getBinaryResourceMediaType

protected javax.ws.rs.core.MediaType getBinaryResourceMediaType(FedoraResource resource)

This method returns a MediaType for a binary resource. If the resource's media type is syntactically incorrect, it will return 'application/octet-stream' as the media type.

Parameters:

resource - the fedora resource

Returns:

the media type of of a binary resource

checksumURI

protected static URI checksumURI(String checksum)

Create a checksum URI object.

Parameters:

checksum - the checksum

Returns:

the new URI, or null

getChildrenLimit

protected int getChildrenLimit()

Calculate the max number of children to display at once.

Returns:

the limit of children to display.

hasRestrictedPath

protected static void hasRestrictedPath(String externalPath)

Check if a path has a segment prefixed with fcr: that is not fcr:metadata or fcr:acl

Parameters:

externalPath - the path.

parseDigestHeader

protected static Collection<URI> parseDigestHeader(String digest)
                                            throws UnsupportedAlgorithmException

Parse the RFC-3230 Digest response header value. Look for a sha1 checksum and return it as a urn, if missing or malformed an empty string is returned.

Parameters:

digest - The Digest header value

Returns:

the sha1 checksum value

Throws:

UnsupportedAlgorithmException - if an unsupported digest is used

checkForInsufficientStorageException

protected void checkForInsufficientStorageException(Throwable rootThrowable,
                                                    Throwable throwable)
                                             throws InvalidChecksumException

Parameters:

rootThrowable - The original throwable

throwable - The throwable under direct scrutiny.

Throws:

InvalidChecksumException - in case there was a checksum mismatch

asNode

protected org.apache.jena.graph.Node asNode(FedoraResource resource)

This is a helper method for using the idTranslator to convert this resource into an associated Jena Node.

Parameters:

resource - to be converted into a Jena Node

Returns:

the Jena node