International

Virtual

Observatory

Alliance

VOSpace specification

Version 1.15

IVOA Proposed Recommendation 2009 September 21

This version:

http://www.ivoa.net/Documents/PR/GWS/PR-VOSpace-1.15-20090921.doc

Latest version:

http://www.ivoa.net/Documents/latest/VOSpace.html

Previous version(s):

PR 1.15 http://www.ivoa.net/Documents/PR/GWS/VOSpace-20090505.doc

PR 1.14 http://www.ivoa.net/Documents/PR/GWS/VOSpace-20081013.doc

PR 1.13 http://www.ivoa.net/Documents/PR/GWS/VOSpace-20081012.doc

PR 1.12 http://www.ivoa.net/Documents/PR/GWS/VOSpace-20080929.doc

WD 1.12 http://www.ivoa.net/Documents/WD/GWS/VOSpace-20080915.doc

WD 1.11 http://www.ivoa.net/Documents/WD/GWS/VOSpace-20080311.doc

Author(s):

Matthew Graham (Editor)

Dave Morris

Guy Rixon

Abstract

VOSpace is the IVOA interface to distributed storage. This version extends the existing VOSpace 1.0 (SOAP-based) specification to support containers, links between individual VOSpace instances, third party APIs, and a find mechanism. Note, however, that VOSpace-1.0 compatible clients will not work with this new version of the interface.

Status of This Document

This is an IVOA Proposed Recommendation made available for public review. The first release of this document (Version 1.10) was 2008 September 30. Previous releases of this document made heavy reference to the VOSpace 1.0 specification, highlighting functional changes between the two versions of the VOSpace interface. This new version is intended to be a standalone specification of the interface, i.e. no external document is required, and incorporates text from the VOSpace 1.0 specification where necessary. The first release of the predecessor Working Draft (Version 1.10) was 2008 March 11.

This is an IVOA Proposed Recommendation made available for public review. It is appropriate to reference this document only as a recommended standard that is under review and which may be changed before it is accepted as a full recommendation.

A list of current IVOA Recommendations and other technical documents can be found at http://www.ivoa.net/Documents/.

Acknowledgements

This document derives from discussions among the Grid and Web Services working group of the IVOA. It is particularly informed by prototypes built by Matthew Graham (Caltech, NVO) and David Morris (Cambridge, Astrogrid).

This document has been developed with support from the National Science Foundation�s Information Technology Research Program under Cooperative Agreement AST0122449 with the John Hopkins University, from the UK Science and Technology Facilities Council (STFC), and from the European Commission�s Sixth Framework Program via the Optical Infrared Coordination Network (OPTICON).

Conformance related definitions

The words �MUST�, �SHALL�, �SHOULD�, �MAY�, �RECOMMENDED�, and �OPTIONAL� (in upper or lower case) used in this document are to be interpreted as described in IETF standard, RFC 2119 [RFC 2119].

The Virtual Observatory (VO) is a general term for a collection of federated resources that can be used to conduct astronomical research, education, and outreach. The International Virtual Observatory Alliance (IVOA) is a global collaboration of separately funded projects to develop standards and infrastructure that enable VO applications. The International Virtual Observatory (IVO) application is an application that takes advantage of IVOA standards and infrastructure to provide some VO service.

Contents

1 Introduction 4

1.1 Typical use of a VOSpace service 5

1.2 Document roadmap 7

2 VOSpace identifiers 7

3 VOSpace data model 9

3.1 Nodes and node types 9

3.2 Properties 11

3.2.1 Property values 11

3.2.2 Property identifiers 11

3.2.3 Property descriptions 12

3.2.4 Standard properties 13

3.3 Capabilities 13

3.3.1 Example use cases 13

3.3.2 Capability identifiers 14

3.3.3 Capability descriptions 14

3.3.4 UI display name 14

3.3.5 Standard capabilities 15

3.4 Views 15

3.4.1 Example use cases 16

3.4.2 View identifiers 17

3.4.3 View descriptions 18

3.4.4 Default views 18

3.4.5 Container views 19

3.5 Protocols 20

3.5.1 Protocol identifiers 20

3.5.2 Protocol descriptions 20

3.5.3 Standard protocols 21

3.5.4 Custom protocols 21

3.6 Transfers 23

3.6.1 Synchronous transfers 23

3.6.2 Asynchronous transfers 24

4 Access control 25

5 Web service operations 25

5.1 Service metadata 26

5.1.1 getProtocols 26

5.1.2 getViews 26

5.1.3 getProperties 27

5.2 Creating and manipulating data nodes 27

5.2.1 createNode 27

5.2.2 deleteNode 28

5.2.3 listNodes 29

5.2.4 findNodes 31

5.2.5 moveNode 32

5.2.6 copyNode 34

5.3 Accessing metadata 35

5.3.1 getNode 35

5.3.2 setNode 36

5.4 Transferring data 37

5.4.1 pushToVoSpace 37

5.4.2 pullToVoSpace 38

5.4.3 pullFromVoSpace 40

5.4.4 pushFromVoSpace 41

5.5 Fault arguments 42

5.5.1 InternalFault 42

5.5.2 PermissionDenied 42

5.5.3 InvalidURI 42

5.5.4 NodeNotFound 42

5.5.5 DuplicateNode 42

5.5.6 InvalidToken 42

5.5.7 InvalidArgument 42

5.5.8 TypeNotSupported 43

5.5.9 ViewNotSupported 43

5.5.10 InvalidData 43

5.5.11 LinkFoundFault 43

6 Appendix 1: Machine readable definitions 43

6.1 WSDL 43

6.2 Message schema 43

7 Appendix 2: Compliance matrix 43

References 46

1 Introduction

VOSpace is the IVOA interface to distributed storage. It specifies how VO agents and applications can use network attached data stores to persist and exchange data in a standard way.

A VOSpace web service is an access point for a distributed storage network. Through this access point, a client can:

� add or delete data objects

� manipulate metadata for the data objects

� obtain URIs through which the content of the data objects can be accessed

VOSpace does not define how the data is stored or transferred, only the control messages to gain access. Thus, the VOSpace interface can readily be added to an existing storage system.

When we speak of �a VOSpace�, we mean the arrangement of data accessible through one particular VOSpace service.

Each data object within a VOSpace service is represented as a node. A useful analogy to have in mind when reading this document is that a node is equivalent to a file.

Nodes in VOSpace have unique identifiers expressed as URIs in the 'vos://' scheme, as defined below.

VOSpace 1.0 [VOSpace] defined a flat, unconnected data space. VOSpace 1.1 builds on top of this and introduces the following new functionality:

containers - this allows the grouping of data in a hierarchical fashion
links - this allows the federation of distinct VOSpace services
third party APIs - this allows data objects and collections to be exposed through other interfaces
find - this offers a more extensive search capability than is provided by list with wildcard support

1.1 Typical use of a VOSpace service

A typical use case for VOSpace is uploading a local data file to a remote VOSpace service. The user will specify the name for the data file in the VOSpace (its node identifier), and any metadata (its properties) that they want to associate with it, e.g. MIME type. They will then describe the data format (the view) they want to use in uploading the file, e.g. VOTable, and the transport protocol (the protocol) that they want to employ to upload the file, e.g. HTTP PUT. This will result in a SOAP request to the service resembling this:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

xmlns:xsi="http://www.w3.org/2001/XMLSchema�instance">

<soapenv:Header>

<soapenv:Body>

<PushToVoSpace xmlns="http://www.net.ivoa/xml/VOSpaceContract�v1.1"

xmlns:vost=�http://www.net.ivoa/xml/VOSpaceTypes�v1.1�>

<vost:destination uri="vos://nvo.caltech!vospace/mytable1"

xsi:type="vost:UnstructuredDataNodeType">

<vost:properties>

<vost:property uri="ivo://ivoa.net/vospace/core#mimetype" xsi:type="vost:PropertyType">text/xml</vost:property>

</vost:properties>

</vost:destination>

<vost:transfer>

<vost:view uri="ivo://ivoa.net/vospace/core#votable"/>

<vost:protocol uri="ivo://ivoa.net/vospace/core#http�put"/>

</vost:transfer>

</PushToVoSpace>

</soapenv:Body>

</soapenv:Envelope>

The service will reply with the representation of the data file in the VOSpace (a description of the node) and the details of the data transfer, i.e. the URL that the user will PUT the data file to. This will involve a SOAP response similar to:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

xmlns:xsi="http://www.w3.org/2001/XMLSchema�instance">

<soapenv:Header>

<soapenv:Body>

<PushToVoSpaceResponse xmlns="http://www.net.ivoa/xml/VOSpaceContract�v1.1"

xmlns:vost=�http://www.net.ivoa/xml/VOSpaceTypes�v1.1�>

<vost:destination uri="vos://nvo.caltech!vospace/mytable1"

xsi:type="vost:UnstructuredDataNodeType">

<vost:properties>

<vost:property uri="ivo://ivoa.net/vospace/core#mimetype"

xsi:type="vost:PropertyType">text/xml</vost:property>

</vost:properties>

</vost:destination>

<vost:transfer>

<vost:view uri="ivo://ivoa.net/vospace/core#votable"/>

<vost:protocol uri="ivo://ivoa.net/vospace/core#http�put">

<vost:endpoint>http://nvo.caltech.edu:

7777/aabcf5�348874�9873ca�9a9ab4</vost:endpoint>

<vost:protocol>

</vost:transfer>

</PushToVoSpaceResponse>

</soapenv:Body>

</soapenv:Envelope>

The user will then use a regular HTTP client to transfer (PUT) the local file to the specified endpoint. This illustrates an important point about VOSpace – it is only concerned with the management of data storage and transfer. A client negotiates the details of a data transfer with a VOSpace service but the actual transfer of bytes across a network is handled by other tools.

Similarly, when a user wants to retrieve a data file from a VOSpace service, they will specify the identifier for the data file in the VOSpace, the data format (view) they want to use in downloading the file, e.g. VOTable, and the transport protocol (the protocol) that they want to employ to download the file, e.g. HTTP GET. This will result in a SOAP request to the service resembling this:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

xmlns:xsi="http://www.w3.org/2001/XMLSchema�instance">

<soapenv:Header>

<soapenv:Body>

<PullFromVoSpace xmlns="http://www.net.ivoa/xml/VOSpaceContract�v1.1"

xmlns:vost=�http://www.net.ivoa/xml/VOSpaceTypes�v1.1�>

<vost:source>vos://nvo.caltech!vospace/mytable1</vost:source>

<vost:transfer>

<vost:view uri="ivo://ivoa.net/vospace/core#votable"/>

<vost:protocol uri="ivo://ivoa.net/vospace/core#httpget"/>

</vost:transfer>

</PullFromVoSpace>

</soapenv:Body>

</soapenv:Envelope>

The service will reply with a SOAP response similar to:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/"

xmlns:xsd="http://www.w3.org/2001/XMLSchema"

xmlns:xsi="http://www.w3.org/2001/XMLSchema�instance">

<soapenv:Header>

<soapenv:Body>

<vost:transfer>

<vost:view uri="ivo://ivoa.net/vospace/core#votable"/>

<vost:protocol uri="ivo://ivoa.net/vospace/core#httpget">

<vost:endpoint>http://nvo.caltech.edu:7777/79f45�3ab0�4de2�bd6c�

ff016082fd</vost:endpoint>

<vost:protocol>

</vost:transfer>

</PullFromVoSpaceResponse>

</soapenv:Body>

</soapenv:Envelope>

The user can then download the data file by pointing an HTTP client (e.g. web browser) at the specified endpoint.

1.2 Document roadmap

The rest of this document is structured as follows:

In Section 2, we specify the URI syntax for identifying data objects (nodes) in VOSpace.

In Section 3, we present the data model that underpins the VOSpace architecture. This consists of a number of data structures, which have XML representations that are used across the wire in SOAP message to and from a VOSpace service. These structures represent the data objects themselves (nodes), metadata that can be associated with a data object (properties), third-party interfaces to the data (capabilities), the data format used when transferring data objects across the wire (views), the transport protocol employed in a data transfer (protocols) and the data transfer itself (transfers).

In Section 4, we outline how access control policies are currently handled in VOSpace.

In Section 5, we detail the operations that VOSpace interface supports and exposes through its WSDL. These handle access to service-level metadata, the creation and manipulation of nodes within the VOSpace, access to node metadata (properties) and data transfer to and from the VOSpace.

2 VOSpace identifiers

The identifier for a node in VOSpace SHALL be a URI with the scheme vos://.

Such a URI shall have the following parts with the meanings and encoding rules defined in RFC2396 [2].

� scheme

� naming authority

� path

� (optional) query

� (optional) fragment identifier

The naming authority for a VOSpace node shall be the VOSpace service through which the node was created. The authority part of the URI shall be constructed from the IVO registry identifier [2] for that service by deleting the ivo:// prefix and changing all forward-slash characters(�/�) in the resource key to exclamation marks (�!�).

This is an example of a possible VOSpace identifier.

vos://nvo.caltech!vospace/myresults/siap�out�1.vot

� The URI scheme is vos://

Using a separate URI scheme for VOSpace identifiers enables clients to distinguish between IVO registry identifiers and VOSpace identifiers.

� nvo.caltech!vospace

is the authority part of the URI, corresponding to the IVO registry identifier

� ivo://nvo.caltech/vospace

This is the IVO registry identifier of the VOSpace service that contains the node.

� /siap�out�1.vot is the URI path

Slashes in the URI path imply a hierarchical arrangement of data: the data object identified by vos://nvo.caltech!vospace/myresults/siap-out-1.vot is within the container identified by vos://nvo.caltech!vospace/myresults.

All ancestors in the hierarchy must be resolvable as containers (ContainerNodes), all the way up to the root node of the space (this precludes any system of implied hierarchy in the naming scheme for nodes with ancestors that are just logical entities and cannot be reified, e.g. the Amazon S3 system).

A VOSpace identifier is globally unique, and identifies one specific node in a specific VOSpace service.

A client should use the following procedure to resolve access to a VOSpace node from a VOSpace identifier:

� Extract the authority part of the VOSpace URI

� Convert the authority back to the IVO registry identifier of the VOSpace service by changing any �!� characters to �/� and adding the ivo:// prefix

� Resolve the IVO registry identifier to an endpoint for the VOSpace service using the IVO resource registry

� Access the node via the endpoint using one of the web service methods defined in this standard

Given the example identifier

vos://org.astrogrid.cam!vospace!container-6/siap-out-1.vot?foo=bar#baz

processing the URI to resolve the VOSpace service would involve :

� Extract the authority part of the VOSpace URI

o org.astrogrid.cam!vospace!container�6

� Convert the authority back to the IVO registry identifier of the VOSpace service by changing any �!� characters to �/�

o org.astrogrid.cam/vospace/container�6

� Adding the ivo:// prefix

o ivo://org.astrogrid.cam/vospace/container�6

� Using the IVO registry to resolve the VOSpace service endpoint from the IVO identifier

3 VOSpace data model

3.1 Nodes and node types

We refer to the arrangement of data accessible through one particular VOSpace service as �a VOSpace�.

Each data object within a VOSpace SHALL be represented as a node that is identified by a URI.

There are different types of nodes and the type of a VOSpace node determines how the VOSpace service stores and interprets the node data.

The types are arranged in a hierarchy, with more detailed types inheriting the structure of

more generic types.

The following types are defined:

� Node is the most basic type

� ContainerNode describes a data item that can contain other data items

� DataNode describes a data item stored in the VOSpace

� UnstructuredDataNode describes a data item for which the VOSpace does not understand the data format

When data is stored and retrieved from an UnstructuredDataNode, the bit pattern read back shall be identical to that written.

� StructuredDataNode describes a data item for which the space understands the format and may make transformations that preserve the meaning of the data.

When data is stored and retrieved from a StructuredDataNode, the bit pattern returned may be different to the original. For example, storing tabular data from a VOTable file will preserve the tabular data, but any comments in the original XML file may be lost.

LinkNode describes a node that points to another node.

A Node MUST have the following elements:

� uri : the vos:// identifier for the node , URI-encoded according to RFC2396 [2]

� properties : a set of metadata properties for the node

� capabilities: a third-party interface to a data object

In addition, a DataNode MUST have the following elements:

� accepts: a list of the views (data formats) that the node can accept

� provides: a list of the views (data formats) that the node can provide

� busy: a boolean flag to indicate that the data associated with the node cannot be accessed

The busy flag is used to indicate that an internal operation is in progress, and the node data is not available.

A LinkNode MUST have the following elements, in addition to the Node elements:

� target: the target URI, URI-encoded according to RFC2396 [2]

The link target can be a URI that points to any type of resource, including other VOSpace Nodes (within the same VOSpace service or in another service), or external resources outside VOSpace altogether.

The properties of a LinkNode do not propagate to the target of the LinkNode. One use case is to enable third-party annotations to be associated with a resource but without the resource itself getting cluttered with unnecessary metadata. In this case, the client creates a LinkNode pointing to the resource in question and then adds the annotations as properties of the LinkNode.

Both the ContainerNode and the LinkNode MUST have no data bytes associated with them.

The set of node types defined by this standard is closed; new types may be introduced only via new versions of the standard.

To comply with the standard, a client or service MUST be able to parse XML representations of all the node types defined in the current specification.

Note - This does not require all services to support all of the Node types, just that it can process an XML request containing any of the types. If the service receives a request for a type that it does not support, the service should return a TypeNotSupported fault. The service must not throw an XML parser error if it receives a request for a type that it does not support.

3.2 Properties

Properties are simple string-based metadata properties associated with a node.

Individual Properties should contain simple short string values, not large blocks of information. If a system needs to attach a large amount of metadata to a node, then it should either use multiple small Properties, or a single Property containing a URI or URL pointing to an external resource that contains the additional metadata.

A Property MUST have the following elements:

� uri : the Property identifier

� value : the string value of the Property

� readOnly : a boolean flag to indicate that the Property cannot be changed by the client

Properties may be set by the client or the service.

3.2.1 Property values

Unless they have special meaning to the service or client, Properties are treated as simple string values.

Some Properties may have meaning to the service, others may have meaning only to one specific type of client. A service implementation does not need to understand the meaning of all the Properties of a node. Any Properties that it does not understand can simply be stored as text strings.

3.2.2 Property identifiers

Every new type of Property SHALL require a unique URI to identify the Property and its meaning.

The rules for the Property identifiers are similar to the rules for namespace URIs in XML schema. The only restriction is that it must be a valid (unique) URI.

� An XML schema namespace identifier can be just a simple URN, e.g. urn:my�namespace

� Within the IVOA, the convention for namespace identifiers is to use a HTTP URL pointing to the namespace schema or a resource describing it

The current VOSpace schema defines Property identifiers as anyURI. The only restriction is that it must be a valid (unique) URI.

� A Property URI can be a simple URN, e.g. urn:my�property

This may be sufficient for testing and development on a private system, but it is not scalable for use on a public service.

For a production system, any new Properties should have unique URIs that can be resolved into to a description of the Property.

Ideally, these should be IVO registry URIs that point to a description registered in the IVO registry:

� ivo://my�registry/vospace/properties#my�property

Using an IVO registry URI to identify Properties has two main advantages :

� IVO registry URIs are by their nature unique, which makes it easy to ensure that different teams do not accidentally use the same URI

� If the IVO registry URI points to a description registered in the IVO registry, this provides a mechanism to discover what the Property means

3.2.3 Property descriptions

If the URI for a particular Property is resolvable, i.e. an IVO registry identifier or a HTTP URL, then it should point to an XML resource that describes the Property.

A Property description should describe the data type and meaning of a Property.

A PropertyDescription should have the following members :

� uri : the formal URI of the Property

� DisplayName : A display name for the Property

� Description : A text block describing the meaning and validation rules of the Property

A PropertyDescription may have the following optional members :

� UCD : the Universal Content Descriptor (in the UCD1+ scheme) for the Property

� Unit : the unit of measurement of the Property

The information in a Property description can be used to generate a UI for displaying and modifying the different types of Properties.

Note that at the time of writing, the schema for registering PropertyDescriptions in the IVO registry has not been finalized.

3.2.3.1 UI display name

If a client is unable to resolve a Property identifier into a description, then it may just display the identifier as a text string:

� urn:modified�date

If the client can resolve the Property identifier into a description, then the client may use the information in the description to display a human readable name and description of the Property:

� Last modification date of the node data

3.2.3.2 Property editors

If the client is unable to resolve a Property identifier into a description, or does not understand the type information defined in the description, then the client may treat the Property value as a simple text string.

If the client can resolve the Property identifier into a description, then the client may use the information in the description to display an appropriate editing tool for the Property.

In the current version of the specification the rules for editing Properties are as follows:

� A service may impose validation rules on the values of specific types of Properties

� If a client attempts to set a Property to an invalid value, then the service may reject the change

� Where possible, the validation rules for a type of Property should be defined in the Property description

Future versions of the VOSpace specification may extend the PropertyDescription to include more specific machine readable validation rules for a Property type.

Note that at the time of writing, the schema for registering validation rules in PropertyDescriptions has not been finalized.

3.2.4 Standard properties

Property URIs and PropertyDescriptions for the core set of Properties will be registered as soon as extension schemas are supported. However, this is not intended to be a closed list, different implementations are free to define and use their own Properties.

3.3 Capabilities

A Capability describes a third-party interface to a node. One application of this would be to enable data access to a node or its contents using a 3^rd party service interface.

A Capability SHALL have the following members:

uri: the Capability identifier
endpoint: the endpoint URL to use for the third-party interface
param: a set of parameters for the capability

3.3.1 Example use cases

A ContainerNode containing image files may offer a DAL SIAP capability so that the images in the container can be accessed using a SIAP service. In this way, a user could create a (DAL enabled) Container in VOSpace, transfer some images into it and then query the set of images using the SIAP interface.

Another example is a DataNode that provides an iRODS capability so that the data replication for this data object can be handled using the iRODS service API.

3.3.2 Capability identifiers

Every new type of Capability SHALL require a unique URI to identify the Capability. The rules for the Capability identifiers are similar to the rules for namespace URIs in XML schema. The only restriction is that it must be a valid (unique) URI.

An XML schema namespace identifier can be just a simple URN, e.g. urn:my-namespace
Within the IVOA, the convention for namespace identifiers is to use a HTTP URL pointing to the namespace schema, or a resource describing it.

The VOSpace schema defines Capability identifiers as anyURI. The only restriction is that it must be a valid (unique) URI.

A Capability URI can be a simple URN, e.g. urn:my-capability

This may be sufficient for testing and development on a private system, but it is not suitable for use on a public service. For a production system, any new Capabilities should have unique URIs that can be resolved into a description of the Capability. Ideally, these should be IVO registry URIs that point to a description registered in the IVO registry:

ivo://my-registry/vospace/capabilities#my-capability

Using an IVO registry URI to identify Capabilities has two main advantages:

IVO registry URIs are by their nature unique, which makes it easy to ensure that different teams do not accidentally use the same URI
If the IVO registry URI points to a description registered in the IVO registry, this provides a mechanism to discover how to use the Capability.

3.3.3 Capability descriptions

If the URI for a particular Capability is resolvable, i.e. an IVO registry identifier or a HTTP URL then it should point to an XML resource that describes the Capability.

A CapabilityDescription should describe the third-party interface and how it should be used in this context. A CapabilityDescription should have the following members:

uri: the formal URI of the Capability
DisplayName: a simple display name of the Capability.
Description: a text block describing the third-party interface and how it should be used in this context.

Note that at the time of writing, the schema for registering CapabilityDescriptions in the IVO registry has not been finalized.

3.3.4 UI display name

If a client is unable to resolve a Capability identifier into a description then it may just display the identifier as a text string:

Access data using urn:edu.sdsc.irods

If a client can resolve the Capability identifier into a description then the client may use the information in the description to display a human readable name and description of the Capability:

Access data using iRODS

3.3.5 Standard capabilities

Capability URIs and CapabilityDescriptions for the core set of Capabilities will be registered as soon as extension schemas are supported. The following URIs SHALL be used to represent the service capabilities:

� ivo://ivoa.net/vospace/core#vospace-1.0 SHALL be used as the capability URI for a VOSpace 1.0 service

� ivo://ivoa.net/vospace/core#vospace-1.1 SHALL be used as the capability URI for a VOSpace 1.1 service

� ivo://ivoa.net/vospace/core#vospace-2.0 SHALL be used as the capability URI for a VOSpace 2.0 service

If a service implementation supports more than one version of the VOSpace interface then these capability URIs can be used with a VOSpace service to identify different VOSpace capabilities for a node.

One use case for this would be a VOSpace 1.1 client talking to a service that implements both VOSpace 1.0 and VOSpace 1.1, where the client is acting on behalf of a third party agent that only understand VOSpace 1.0. In this case, the client can use the information in the VOSpace 1.0 capability to direct the third party agent to the VOSpace 1.0 endpoint.

Other standard service interfaces will also be registered, e.g.

Cone Search
SIAP
SSAP
TAP

However, this is not intended to be a closed list and different implementations are free to define and use their own Capabilities.

3.4 Views

A View describes the data formats and contents available for importing or exporting data to or from a VOSpace node.

The metadata for a DataNode contains two lists of Views.

� accepts is a list of Views that the service can accept for importing data into the Node

� provides is a list of Views that the service can provide for exporting data from Node

A View SHALL have the following members:

� uri the View identifier

� original: an optional boolean flag to indicate that the View preserves the original bit pattern of the data

� param: a set of name-value pairs that can be used to specify additional arguments for the View

3.4.1 Example use cases

3.4.1.1 Simple file store

A simple VOSpace system that stores data as a binary files can just return the contents of the original file. The client supplies a View identifier when it imports the data, and the service uses this information to describe the data to other clients.

A file based system can use the special case identifier 'ivo://ivoa.net/vospace/core#view�any' to indicate that it will accept any data format or

View for a Node.

For example:

� A client imports a file into the service, specifying a View to describe the file contents

� The service stores the data as a binary file and keeps a record of the View

� The service can then use the View supplied by the client to describe the data to other clients

This type of service is not required to understand the imported data, or to verify that it

contents match the View, it treats all data as binary files.

3.4.1.2 Database store

A VOSpace system that stores data in database tables would need to be able to understand the data format of an imported file in order to parse the data and store it correctly. This means that the service can only accept a specific set of Views, or data formats, for importing data into the Node.

In order to tell the client what input data formats it can accept, the service publishes a list of specific Views in the accepts list for each Node.

On the output side, a database system would not be able to provide access to the original input file. The contents of file would have been transferred into the database table and then discarded. The system has to generate the output results from the contents of the database table.

In order to support this, the service needs to be able to tell the client what Views of the data are available.

A database system may offer access to the table contents as either VOTable or FITS files, it may also offer zip or tar.gz compressed versions of these. In which case the system needs to be able to express nested file formats such as 'zip containing VOTable' and 'tar.gz containing FITS'.

A service may also offer subsets of the data. For example, a work flow system may only want to look at the table headers to decide what steps are required to process the data. If the table contains a large quantity of data, then downloading the whole contents just to look at the header information is inefficient. To make this easier, a database system may offer a 'metadata only' View of the table, returning a VOTable or FITS file containing just the metadata headers and no rows.

So our example service may want to offer the following Views of a database table:

� Table contents as FITS

� Table contents as VOTable

� Table contents as zip containing FITS

� Table contents as zip containing VOTable

� Table contents as tar.gz containing FITS

� Table contents as tar.gz containing VOTable

� Table metadata as FITS

� Table metadata as VOTable

The service would publish this information as a list of Views in the provides section of the metadata for each Node.

The VOSpace specification does not mandate what Views a service must provide. The VOSpace specification is intended to provide a flexible mechanism enabling services to describe a variety of different Views of data. It is up to the service implementation to decide what Views of the data it can accept and provide.

3.4.2 View identifiers

Every new type of View SHALL require a unique URI to identify the View and its content.

The rules for the View identifiers are similar to the rules for namespace URIs in XML schema. The only restriction is that it must be a valid (unique) URI.

� An XML schema namespace identifier can be just a simple URN, e.g. urn:my�namespace

� Within the IVOA, the convention for namespace identifiers is to use a HTTP URL pointing to the namespace schema, or a resource describing it

The current VOSpace schema defines View identifiers as anyURI. The only restriction is that it must be a valid (unique) URI.

� A View URI can be a simple URN, e.g. urn:my�view

This may be sufficient for testing and development on a private system, but it is not scalable for use on a public service.

For a production system, any new Views should have unique URIs that can be resolved into to a description of the View.

Ideally, these should be IVO registry URIs that point to a description registered in the IVO registry:

� ivo://my�registry/vospace/views#my�view

Using an IVO registry URI to identify Views has two main advantages :

� IVO registry URIs are by their nature unique, which makes it easy to ensure that different teams do not accidentally use the same URI

� If the IVO registry URI points to a description registered in the IVO registry, this provides a mechanism to discover what the View contains

3.4.3 View descriptions

If the URI for a particular View is resolvable, i.e. an IVO registry identifier or a HTTP URL, then it should point to an XML resource that describes the View.

A ViewDescription should describe the data format and/or content of the view.

A ViewDescription should have the following members :

� Uri: the formal URI of the View

� DisplayName: A simple text display name of the View

� Description: Text block describing the data format and content of the View

A ViewDescription may have the following optional members :

� MimeType : the standard MIME type of the View, if applicable

However, at the time of writing, the schema for registering ViewDescriptions in the IVO registry has not been finalized.

3.4.3.1 UI display name

If a client is unable to resolve a View identifier into a description, then it may just display the identifier as a text string:

� Download as urn:table.meta.fits

If the client can resolve the View identifier into a description, then the client may use the

information in the description to display a human readable name and description of the View:

� Download table metadata as FITS header

3.4.3.2 MIME types

If a VOSpace service provides HTTP access to the data contained in a Node, then if the ViewDescription contains a MimeType field, this should be included in the appropriate header field of the HTTP response.

3.4.4 Default views

The following standard URIs SHALL be used to refer to the default import and export views:

� ivo://ivoa.net/vospace/core#anyview SHALL be used as the view URI to indicate that a service will accept any view for an import operation

� ivo://ivoa.net/vospace/core#binaryview SHALL be used as the view URI to import or export data as a binary file

� ivo://ivoa.net/vospace/core#defaultview SHALL be used by a client to indicate that the service should choose the most appropriate view for a data export

3.4.4.1 Default import view

If a client imports data using this view, the data SHALL be treated as a binary BLOB, and stored as is with no additional processing. This is equivalent to the application/binary MIME type.

Note, this view is OPTIONAL, and the service may throw a ViewNotSupported exception if it does not accept this view. In particular, this view cannot be used to import data into a StructuredDataNode as the service needs to know about and understand the data format to be able to create the StructuredDataNode.

Note, this view is only valid for the data import operations, pullToVoSpace and pushToVoSpace. If this view is requested in an export operation, pullFromVoSpace and pushToVoSpace, then the service SHOULD throw a ViewNotSupported exception.

3.4.4.2 Default export view

If a client requests data using this view, the server SHALL choose whichever of the available views (the server) thinks is the most appropriate, based on how the data is stored. In a simple file-based system, this will probably be the same format that the data was originally imported in. In a database table system, this will probably either be VOTable or CVS, depending on the level of metadata available.

Note, this view is OPTIONAL, and the server may throw a ViewNotSupported exception if it does not provide this view. However, in most cases, it is expected that a service would be able to select an appropriate �default� format for data held
within the service.

Note, this view is only valid for the data export operations, pullFromVoSpace and pushFromVoSpace. If this view is requested in an import operation, pullToVoSpace and pushToVoSpace, then the service SHOULD throw a ViewNotSupported fault.

3.4.5 Container views

In VOSpace 1.1, a view of a ContainerNode describes the data representation (format) of a file or data stream that represents the combined contents of the node and its children. If the view describes an archive format (tar, zip, etc.) then a service that accepts this view (format) for a ContainerNode SHALL provide access to the archive contents as children nodes of the container. Whether or not the service actually unpacks the archive is implementation dependent but the service SHALL behave as though it has done so. For example, a client may want to upload a tar file containing several images to a VOSpace service. If they associate it with (upload it to) a UnstructuredDataNode then it will be treated as a blob and its contents will be not be available. However, if they upload it to a ContainerNode with an accepts view of "tar" then the image files within the tar file will be represented as children nodes of the ContainerNode and accessible like any other data object within the space.

If a service provides an archive format (tar, zip, etc.) view of a ContainerNode then the service SHALL package the contents of the container and all its child nodes in the specified format.

3.5 Protocols

A Protocol describes the parameters required to perform a data transfer using a particular protocol.

A Protocol SHALL have the following members:

� uri : the Protocol identifier

� endpoint : the endpoint URL to use for the data transfer

� param : A list of name-value pairs that specify any additional arguments required for the transfer

3.5.1 Protocol identifiers

Every new type of Protocol requires a unique URI to identify the Protocol and how to use it.

The rules for the Protocol identifiers are similar to the rules for namespace URIs in XML schema. The only restriction is that it must be a valid (unique) URI

� An XML schema namespace identifier can be just a simple URN, e.g. urn:my�namespace

� Within the IVOA, the convention for namespace identifiers is to use a HTTP URL pointing to the namespace schema, or a resource describing it

The current VOSpace schema defines Protocol identifiers as anyURI. The only restriction is that it must be a valid (unique) URI.

� A Protocol URI can be a simple URN, e.g. urn:my�protocol

This may be sufficient for testing and development on a private system, but it is not scalable for use on a public service.

For a production system, any new Protocols should have unique URIs that can be resolved into to a description of the Protocol.

Ideally, these should be IVO registry URIs that point to a description registered in the IVO registry :

� ivo://my�registry/vospace/protocols#my�protocol

Using an IVO registry URI to identify Protocols has two main advantages:

� IVO registry URIs are by their nature unique, which makes it easy to ensure that different teams do not accidentally use the same URI

� If the IVO registry URI points to a description registered in the IVO registry, this provides a mechanism to discover how to use the Protocol

3.5.2 Protocol descriptions

If the URI for a particular Protocol is resolvable, i.e. an IVO registry identifier or a HTTP URL, then it should point to an XML resource that describes the Protocol.

A ProtocolDescription should describe the underlying transport protocol, and how it should be used in this context.

A ProtocolDescription should have the following members :

� uri : the formal URI of the Protocol

� DisplayName : A simple display name of the Protocol

� Description : Text block describing describing the underlying transport protocol, and how it should be used in this context

However, at the time of writing, the schema for registering ProtocolDescriptions in the IVO registry has not been finalized.

3.5.2.1 UI display name

If a client is unable to resolve a Protocol identifier into a description, then it may just display the identifier as a text string:

� Download using urn:my�protocol

If the client can resolve the Protocol identifier into a description, then the client may use the information in the description to display a human readable name and description of the Protocol:

� Download using standard HTTP GET

3.5.3 Standard protocols

Protocol URIs and ProtocolDescriptions for the core set of standard transport protocols will be registered as soon as extension schemas are supported. The following URIs SHALL be used to represent the standard protocols:

� ivo://ivoa.net/vospace/core#httpget SHALL be used as the protocol URI for a HTTP GET transfer

� ivo://ivoa.net/vospace/core#httpput SHALL be used as the protocol URI for a HTTP PUT transfer

However, this is not intended to be a closed list, different implementations are free to define and use their own transfer Protocols.

3.5.4 Custom protocols

There are several use cases where a specific VOSpace implementation may want to define and use a custom VOSpace transfer Protocol, either extending an existing Protocol, or defining a new one.

3.5.4.1 SRB gateway

One example would be a VOSpace service that was integrated with a SRB system. In order to enable the service to use the native SRB transport protocol to transfer data, the service providers would need to register a new ProtocolDescription to represent the SRB transport protocol.

The ProtocolDescription would refer to the technical specification for the SRB transport protocol, and define how it should be used to transfer data to and from the VOSpace service.

Clients that do not understand the SRB transport protocol would not recognize the URI for the SRB Protocol, and would ignore Transfer options offered using this Protocol.

Clients that were able to understand the SRB transport protocol would recognize the URI for the SRB Protocol, and could use the 'srb://..' endpoint address in a Protocol option to transfer data using the SRB transport protocol.

Enabling different groups to define, register and use their own custom Protocols in this way means that support for new transport protocols can be added to VOSpace systems without requiring changes to the core VOSpace specification.

In this particular example, it is expected that one group within the IVOA will work with the SRB team at SDSC to define and register the Protocol URI and ProtocolDescription for using the SRB protocol to transfer data to and from VOSpace systems.

Other implementations that plan to use the SRB transport protocol in the same way could use the same Protocol URI and ProtocolDescription to describe data transfers using the SRB transport protocol.

The two implementations would then be able use the common Protocol URI to negotiate data transfers using the SRB transport protocol.

3.5.4.2 Local NFS transfers

Another example of a custom Protocol use case would to transfer data using the local NFS file system within an institute.

If an institute has one or more VOSpace services co-located with a number of data processing applications, all located within the same local network, then it would be inefficient to use HTTP get and put to transfer the data between the services if they could all access the same local file system.

In this case, the local system administrators could register a custom ProtocolDescription which described how to transfer data using their local NFS file system.

� ivo://my.institute/vospace/protocols#internal�nfs

Data transfers using this Protocol would be done using file:// URLs pointing to locations within the local NFS file system :

� file:///net/host/path/file

These URLs would only have meaning to services and applications located within the local network, and would not be usable from outside the network.

Services and applications located within the local network would be configured to recognize the custom Protocol URI, and to use local file system operations to move files within the NFS file system.

Services and applications located outside local network would not recognize the custom Protocol URI and so would not attempt to use the internal file URLs to transfer data.

Note that in this example the custom Protocol URI and the associated ProtocolDescription refer to data transfers using file URLs within a specific local NFS file system.

If a different institute wanted to use a similar system to transfer data within their own local network, then they would have to register their own custom Protocol URI and associated ProtocolDescription.

The two different Protocol URIs and ProtocolDescriptions describe how to use the same underlying transport protocol (NFS) in different contexts.

Enabling different groups to define, register and use their own custom Protocols in this way means that systems can be configured to use the best available transport protocols for transferring data, without conflicting with other systems who may be using similar a transport protocol in a different context.

3.6 Transfers

A Transfer describes the details of a data transfer to or from a space.

A Transfer SHALL have the following members:

� view : A View specifying the requested View

o For the transfer to be valid, the specified View must match one of those listed in the accepts or provides list of the Node

� protocol : one or more a Protocols specifying the transfer protocols to use

o A Transfer may contain more than one Protocol element with different Protocol URIs

o A Transfer may contain more than one Protocol element with the same Protocol URI with different endpoints

3.6.1 Synchronous transfers

Two of the VOSpace transfer methods are synchronous - the service performs the data transfer during the scope of the SOAP call.

In these methods, the client constructs a Transfer request containing details of the Node and View and one or more Protocol elements with valid endpoint addresses.

The service may ignore Protocols with URIs that it does not recognize.

If the server is unable to handle any of the requested Protocols in a Transfer request, then it SHALL respond with a fault.

The order of the Protocols in the request indicates the order of preference that the client would like the server to use However, this is only a suggestion, and the server is free to use its own preferences to select which Protocol it uses first.

The service selects the first Protocol it wants to use from the list and attempts to transfer the data using the Protocol endpoint.

If the first attempt fails, the server may choose another Protocol from the list and re-try the transfer using that Protocol endpoint.

The server may attempt to transfer the data using any or all of the Protocols in the list until either, the data transfer succeeds, or there are no more Protocol options left.

The server SHALL be allowed to only use each Protocol option once. This allows a data source to issue one time URLs for a Transfer, and cancel each URL once it has been used.

Once one of the Protocol options succeeds the transfer SHALL be considered to have completed, and the server is not allowed to use any of the remaining Protocol options. This allows a data source to issue a set of one time URLs for a transfer, and to cancel any unused URLs once the transfer has been completed.

Some Protocols may require the service to call a callback address when a data transfer completes. This behavior is specific to the Protocol, and should be defined in the ProtocolDescription.

If none of the Protocol options succeed, then the transfer SHALL be considered to have failed, and the service SHALL return a fault containing details of the Protocol options it tried.

3.6.2 Asynchronous transfers

Two of the VOSpace transfer methods are asynchronous - an external actor performs the data transfer outside the scope of the SOAP call.

In these methods, the client sends a template Transfer request to the server.

The Transfer request should contain details of the Node and View and one or more Protocol elements without endpoint addresses.

In effect, the client is sending a list of Protocols that it (the client) wants to use for the transfer.

The service may ignore Protocols with URIs that it does not recognize.

The service selects the Protocols from the request that it is capable of handling, and builds a Transfer response containing the selected Protocol elements filling in valid endpoint addresses for each of them.

The order of the Protocol elements in the request indicates the order of preference that the client would like to use. However, this is only a suggestion, and the server is free to use its own preferences when generating the list of Protocols in the response.

In effect, the server is responding with the subset of the requested Protocols that it (the server) is prepared to offer.

If the server is unable to accept any of the requested Protocols, then it SHALL respond with a fault.

On receipt of the response, the client can use the list of Protocols itself, or pass them on to another agent to perform the data transfer on its behalf.

The agent may ignore Protocols URIs that it does not recognize.

The agent selects the first Protocol it wants to use from the list and attempts to transfer the data using the Protocol endpoint.

If the first attempt fails, the agent may choose another Protocol from the list and re-try the transfer using that Protocol endpoint.

The agent may attempt to transfer the data using any or all of the Protocols in the list until either, the data transfer succeeds, or there are no more Protocol options left.

The agent SHALL be allowed to only use each Protocol option once. This allows a data source to issue one time URLs for a Transfer, and cancel each URL once it has been used.

Once one of the Protocol options succeeds the transfer SHALL be considered to have completed, The agent is not allowed to use any of the remaining unused Protocol options. This allows a data source to issue a set of one time URLs for a transfer, and to cancel any unused URLs once the transfer has been completed.

Some Protocols may require the agent to call a callback address when a data transfer completes. This behavior is specific to the Protocol, and SHOULD be defined in the ProtocolDescription.

If none of the Protocol options succeed, then the transfer SHALL be considered to have failed.

4 Access control

The access control policy for a VOSpace is defined by the implementor of that space according to the use cases for which the implementation is intended.

A human-readable description of the implemented access policy must be declared in the registry metadata for the space.

These are the most probable access policies:

� No access control is asserted. Any client can create, read, write and delete nodes anonymously

� No authorization is required, but clients must authenticate an identity (for logging purposes) in each request to the space

� Clients may not create or change nodes (i.e. the contents of the space are fixed by the implementation or set by some interface other than VOSpace), but any client can read any node without authentication

� Nodes are considered to be owned by the user who created them. Only the owner can operate on a node

No operations to modify the access policy (e.g. to set permissions on an individual node) are included in this standard. Later versions may add such operations.

Where the access policy requires authentication of callers, the VOSpace service shall support one of the authentication methods defined in the IVOA Single Sign On profile [SSO].

5 Web service operations

A VOSpace 1.1 service shall be a SOAP service with the following operations:

5.1 Service metadata

5.1.1 getProtocols

Get a list of the transfer Protocols supported by the space service.

5.1.1.1 Parameters

� none

5.1.1.2 Returns

� accepts: A list of Protocols that the service SHALL accept

o In this context 'accepting a protocol' means that the service SHALL act as a client for the protocol

o e.g. 'accepting http-get' means the service can read data from an external HTTP web server

� provides: A list of Protocols that the service SHALL provide

o In this context 'providing a protocol' means that the service SHALL act as a server for the protocol

o e.g. 'providing http-get' means the service can act as a http web server

5.1.1.3 Faults

� The service shall throw an InternalFault fault if the operation fails

5.1.2 getViews

Get a list of the Views and data formats supported by the space service.

5.1.2.1 Parameters

� none

5.1.2.2 Returns

� accepts: A list of Views that the service SHALL accept

o In this context 'accepting a view' means that the service SHALL receive input data in this format

o A simple file based system may use the reserved View URI ivo://net.ivoa.vospace/views/any to indicate that it can accept data in any format

� provides: A list of Views that the service SHALL provide

o In this context 'providing a view' means that the service SHALL produce output data in this format

o A simple file based system may use the reserved View URI ivo://net.ivoa.vospace/views/any to indicate that it can provide data in any format

5.1.2.3 Faults

� The service shall throw an InternalFault fault if the operation fails

5.1.3 getProperties

5.1.3.1 Parameters

� none

5.1.3.2 Returns

� accepts: A list of identifiers for the Properties that the service SHALL accept and understand. This refers to metadata (Properties) that is implementation dependent but can be used by a client to control operational aspects of the service: for example, a VOSpace implementation might allow individual users to control the permissions on data objects via a Property called �permissions�. If the VOSpace receives a data object with this Property then it 'understands' what this property refers to and can deal with it accordingly.

� provides: A list of identifiers for the Properties that the service SHALL provide

� contains: A list of identifiers for all the Properties currently used by Nodes within the service

5.1.3.3 Faults

� The service shall throw an InternalFault fault if the operation fails

5.2 Creating and manipulating data nodes

5.2.1 createNode

Create a new node at a specified location.

5.2.1.1 Parameters

� node: A template Node (as defined in Section 3.1) for the node to be created

A valid uri attribute SHALL be required. The name .auto is a reserved URI to indicate an auto-generated URI for the destination, i.e. given the following URI vos://service/path/.auto a service SHALL create a new unique URI for the node within vos://service/path.

If the Node xsi:type is not specified then a generic node of type Node is implied.

The permitted values of xsi:type are:

� vos:Node

� vos:DataNode

� vos:UnstructuredDataNode

� vos:StructuredDataNode

� vos:ContainerNode

� vos:LinkNode

When creating a new Node the service may substitute a valid subtype, i.e. If xsi:type is

set to vos:DataNode then this may be implemented as a DataNode, StructuredDataNode

or an UnstructuredDataNode.

The properties of the new Node can be set by adding Properties to the template.

Attempting to set a Property that the service considers to be 'readonly' SHALL cause a

PermissionDenied fault.

The accepts and provides lists of Views for the Node cannot be set using this method.

The capabilities list for the Node cannot be set using this method.

5.2.1.2 Returns

� node: details of the new Node

The accepts list of Views for the Node SHALL be filled in by the service based on service

capabilities.

The provides list of Views for the Node MAY not be filled in until some data has been

imported into the Node.

The capabilities list for the Node may not be filled in until some data has been imported into the Node.

5.2.1.3 Faults

� The service shall throw an InternalFault fault if the operation fails

� The service shall throw a DuplicateNode fault if a Node already exists with the same URI

� The service shall throw an InvalidURI fault if the requested URI is invalid

� The service shall throw a TypeNotSupported fault if the type specified in xsi:type is not supported

� The service shall throw a PermissionDenied fault if the user does not have permissions to perform the operation

� If a parent node in the URI path does not exist then the service must throw a ContainerNotFound fault.

o For example, given the URI path /a/b/c, the service must throw a ContainerNotFound fault if either /a or /a/b do not exist.

� If a parent node in the URI path is a LinkNode, the service must throw a LinkFound fault.

o For example, given the URI path /a/b/c, the service must throw a LinkFound fault if either /a or /a/b are LinkNodes.

5.2.2 deleteNode

Delete a node.

When the target is a ContainerNode, all its children (the contents of the container) SHALL also be deleted.

5.2.2.1 Parameters

� target: the URI of an existing Node

5.2.2.2 Returns

� void

5.2.2.3 Faults

� The service shall throw an InternalFault fault if the operation fails

� The service shall throw a PermissionDenied fault if the user does not have permissions to perform the operation

� The service shall throw a NodeNotFound fault if the target node does not exist

� If a parent node in the URI path does not exist then the service MUST throw a ContainerNotFound fault

o For example, given the URI path /a/b/c, the service must throw a ContainerNotFound fault if either /a or /a/b do not exist.

� If a parent node in the URI path is a LinkNode, the service must throw a LinkFound fault.

o For example, given the URI path /a/b/c, the service must throw a LinkFound fault if either /a or /a/b are LinkNodes.

� If the target node in the URI path does not exist, the service must throw a NodeNotFound fault.

o For example, given the URI path /a/b/c, the service must throw a NodeNotFound fault if /a/b/c does not exist.

5.2.3 listNodes

List nodes in a space.

In order to support large numbers of nodes, this method uses a continuation token to

enable the list of results to be split across more than response.

When a target URI is a ContainerNode, only direct (first generation) children of the node SHALL be listed.

5.2.3.1 Parameters

� token: An optional continuation token from a previous request

o No token indicates a request for a new list

The server may impose a limited lifetime on the continuation token. If a token has expired,

the server SHALL throw a fault, and the client will have to make a new request.

� limit: An optional limit indicating the maximum number of results in the response

o No limit indicates a request for an unpaged list. However the server may still impose its own limit on the size of an individual response, splitting the results into more than one page if required

� detail: The level of detail in the returned listing

o min : The list contains the minimum detail for each Node with all optional parts removed – the node type should be returned

� e.g. <node uri="vos://service/name" xsi:type=�Node�/>

o max : The list contains the maximum detail for each Node, including any xsi:type specific extensions

o properties : The list contains a basic node element with a list of properties for each Node with no xsi:type specific extensions.

� nodes: A list containing zero or more Nodes identifying the target URIs to be listed

Only the uri of the Nodes in the request list are used, the service SHALL ignore any other

elements or attributes. This method does not perform a search based on the Node

Properties or other attributes.

The Node URIs in the request list MAY contain a '*' wild card character in the name part of

the URI (the remaining text following the last '/' character).

A single request may include more than one target Node containing a wild card. For

example, the following request lists all Nodes with names that that match either '*.xml' or

'*.txt'

<nodes>

</nodes>

</listNodes>

Note that the wild card substitution for the '*' is a simple 'zero or more of any characters'

match.

So a request for '*.txt' will match Nodes with the the following names :

� .txt

� frog.txt

Wild cards MUST only be used in the final part of the URL path: for example, a/b/c/*.txt is allowed but a/*/c/*.txt is not.

This method does not support regular expression matches.

An empty list of target Nodes list SHALL imply a full listing of the space.

A request with an empty list of target Nodes :

</listNodes>

is equivalent to a request with a single target Node URI of '*' :

<nodes>

</nodes>

</listNodes>

5.2.3.2 Returns

� token : An optional continuation token, indicating that the list is incomplete

o The client may use this token to request the next block of Nodes in the sequence

o No token SHALL indicate that the list is complete.

� limit : An optional limit which must be present if a limit parameter was used in the request

o If present, the value is the value from the original request and not any limit imposed by the service

� nodes : A list of the Nodes matching the requested Node URIs

5.2.3.3 Faults

� The service shall throw an InternalFault fault if the operation fails

� The service shall throw a PermissionDenied fault if the user does not have permissions to perform the operation

� The service shall throw a NodeNotFound fault if a specific target Node does not exist

o This does not apply if the target Node URI contains a wild card

� The service shall throw an InvalidToken fault if it does not recognize the continuation token

� The service shall throw an InvalidToken fault if the continuation token has expired

� If a parent node in one of the search paths does not exist then the service must throw a ContainerNotFound fault.

o For example, given the search path /a/b/*, the service must throw a ContainerNotFound fault if either /a or /a/b do not exist.

� If a parent node in one of the search paths is a LinkNode, the service must throw a LinkFound fault.

o For example, given the search path /a/b/*, the service must throw a LinkFound fault if either /a or /a/b are LinkNodes.

5.2.4 findNodes

Find nodes whose properties match the specified values.

This operation is optional.

5.2.4.1 Parameters

token: An optional continuation token from a previous request

No token indicates a request for a new find operation.

The server may impose a limited lifetime on the continuation token. If a token has expired, the server SHALL throw a fault, and the client will have to make a new request.

limit: An optional limit indicating the maximum number of requests in the response

No limit SHALL indicate a request for an unpaged response. However the server may still impose its own limit on the size of an individual response, splitting the results into more than one page if required.

detail: The level of detail in the returned response

min: The response contains the minimum detail for each Node with all optional parts removed – however, the node type should still be returned in the xsi:type attribute

e.g. <node uri="vos://service/name" xsi:type="Node"/>

max: The response contains the maximum detail for each Node, including any type specific extensions
properties: The response contains a basic node element with a list of properties for each Node with no type specific extensions.

matches: A list of match elements identifying the properties and values to match against and whether these should applied in conjunction (and) or disjunction (or).

The match element has a uri attribute to identify the property to which it is applying. The regular expression against which the property values are to be matched is then specified as the value of the match element:

<match uri="..."> regex </match>

The match elements can be combined in conjunction and/or disjunction by specifying them as subelements of <or> and <and> respectively. For example, the predicate "(property1 and property2) or property3" would be specified as:

<or>

<and>

<match uri="property1"> regex </match>

<match uri="property2"> regex </match>

</and>

<match uri="property3"> regex </match>

</or>

The regex syntax must comply with POSIX conventions.

An empty list of <matches> implies a full listing of the space.

5.2.4.2 Returns

token: An optional continuation token, indicating that the response is incomplete

The client may use this token to request the next block of Nodes in the sequence
No token indicates that the list is complete.

limit: An optional limit which must be present if a limit parameter was used in the request

If present, the value is the value from the original request and not any limit imposed by the service

nodes: A list of the Nodes matching the requested properties

5.2.4.3 Faults

The service shall throw an InternalFault fault if the operation fails
The service shall throw a PermissionDenied fault if the user does not have permissions to perform the operation
The service shall throw a PropertyNotFound fault if a particular property is specified and does not exist in the space
The service shall throw an InvalidToken fault if it does not recognize the continuation token
The service shall throw an InvalidToken fault if the continuation token has expired

5.2.5 moveNode

Move a node within a VOSpace service.

Note that this does not cover moving data between two separate VOSpace services.

Moving nodes between separate VOSpace services should be handled by the client, using the import, export and delete methods.

When the source is a ContainerNode, all its children (the contents of the container) SHALL also be moved to the new destination.

When the destination is an existing ContainerNode, the source SHALL be placed under it (i.e. within the container).

5.2.5.1 Parameters

� source: The URI of an existing Node

� destination: A template describing the new Node (as defined in section 3.1).

.auto is a reserved URI to indicate an autogenerated URI for the destination, i.e. vos://service/path/.auto SHALL cause a new unique URI for the node within vos://service/path to be generated.

The Properties from the source Node SHALL be combined with the Properties from the

destination to create the new Node.

The Node type cannot be changed using this method.

The value of the xsi:type attribute on the destination SHALL be ignored and the new Node

SHALL inherit the same type as the original.

The accepts and provides lists of Views for the new Node cannot be set using this method.

5.2.5.2 Returns

� node: Details of the Node in its new location

5.2.5.3 Faults

� The service shall throw an InternalFault fault if the operation fails

� The service SHALL throw a PermissionDenied fault if the user does not have permissions to perform the operation

� The service shall throw a NodeNotFound fault if the source Node does not exist

� The service shall throw a DuplicateNode fault if a Node already exists at the destination

� The service shall throw an InvalidURI fault if a specified URI is invalid

� The service shall throw an InvalidArgument fault if a specified value is invalid

The service shall throw an InvalidArgument fault if request attempts to change the node type.

� If a parent node in the source URI path does not exist then the service must throw a ContainerNotFound fault.

o For example, given the source URI path /a/b/c, the service must throw a ContainerNotFound fault if either /a or /a/b do not exist.

� If a parent node in the source URI path is a LinkNode, the service must throw a LinkFound fault.

o For example, given the source URI path /a/b/c, the service must throw a LinkFound fault if either /a or /a/b are LinkNodes.

� If the source node does not exist, the service must throw a NodeNotFound fault.

o For example, given the source URI /a/b/c, the service must throw a NodeNotFound fault if /a/b/c does not exist.

� If a parent node in the destination URI path does not exist then the service must throw a ContainerNotFound fault.

o For example, given the destination URI /x/y/z, the service must throw a ContainerNotFound fault if either /x or /x/y do not exist.

� If a parent node in the destination URI is a LinkNode, the service must throw a LinkFound fault.

o For example, given the destination URI /x/y/z, the service must throw a LinkFound fault if either /x or /x/y are LinkNodes.

� If the destination URI points to an existing DataNode, the service must throw a DuplicateNode fault.

o For example, given the destination URI /x/y/z, the service must throw a DuplicateNode fault if /x/y/z is a DataNode.

If the destination URI points to an existing LinkNode, the service must throw a LinkFound fault.

For example, given the destination URI /x/y/z, the service must throw a LinkFound fault of /x/y/z is a LinkNode.

5.2.6 copyNode

Copy a node with a VOSpace service.

Note that this does not cover copying data between two separate VOSpace services.

Copying nodes between separate VOSpace services should be handled by the client, using the import and export methods.

When the source is a ContainerNode, all its children (the full contents of the container) SHALL get copied, i.e. this is a deep recursive copy.

When the destination is an existing ContainerNode, the copy SHALL be placed under it (i.e. within the container).

5.2.6.1 Parameters

� source: The URI of an existing Node

� destination: A template Node (as defined in section 3.1) describing the new Node

.auto is the reserved URI to indicate an auto-generated URI for the destination, i.e. vos://service/path/.auto SHALL cause a new unique URI for the node within vos://service/path to be generated.

The Properties from the source Node SHALL be combined with the Properties from request to

create the new Node.

The Node type cannot be changed using this method.

The value of the xsi:type attribute on the destination SHALL be ignored and the new Node

SHALL inherit the same type as the original.

The accepts and provides lists of Views for the new Node cannot be set using this method.

5.2.6.2 Returns

� node: Details of the new Node

5.2.6.3 Faults

� The service shall throw an InternalFault fault if the operation fails

� The service shall throw a PermissionDenied fault if the user does not have permissions to perform the operation

� The service shall throw a NodeNotFound fault if the source Node does not exist

� The service shall throw a DuplicateNode fault if a Node already exists at the destination

� The service shall throw an InvalidURI fault if a specified URI is invalid

� The service shall throw an InvalidArgument fault if a specified value is invalid

The service shall throw an InvalidArgument fault if request attempts to change the node type.