Deuri is the URL scheme Open Data Portal [[!ODP]] of the European Union. Once minted, deuris must exist forever, though redirection techniques could be used.
http://data.europa.eu/eurovoc/4532
This document is a draft specification of the Persistent URI Task Force of the European institutions. Send comments to the editor.
The Deuri components are:
http://data.europa.eu/foo/bar
\___________________/\___/\_/
| | |
head | local
collection
The following strings are placeholder names (metasyntactic variables):
foo, and
bar.
Head
is the
scheme
and the
authority.
It is the fix string
http://data.europa.eu.
Any part of this document stating
http
must be read as stating
http
and
https.
Collection is the first path segment. A collection is allocated by the Collection Registrar to a Local Minter. Synonyme of collection id.
Local is the path excluding the collection. Local can be composed of several path segments. Local are minted by Local Minters. Synonyme of local id.
It must conform to the following:
Clients can send deuris in any case combination, but the returned dueris must be in lower case. Note that in URI the scheme and authority are case-insensitive and the path is case-sensitive.
The format and language variants can be indicated in the URI using dot extensions. These and other variants can also be requested using content negotiation.
http://data.europa.eu/foo/bar # Resource - variant as per the negotiation http://data.europa.eu/foo/bar.de.html # German, HTML http://data.europa.eu/foo/bar.de.pdf # German, PDF http://data.europa.eu/foo/bar.en.pdf # English, PDF http://data.europa.eu/foo/bar.de # German - format variant as per the negotiation http://data.europa.eu/foo/bar.html # HTML - language variant as per the negotiation
Collection naming should follow current practices;
for example,
a collection for
EuroVoc should be named
eurovoc.
For new collections, the
Collection Registrar
will allocate by default an
opaque collection name;
Local Minters
could request a
mnemonic collection name.
Reserved collection are the ones reserved for the functioning of the Open Data Portal.
Collection home is the resource associated with a collection.
http://data.europa.eu/foo # this return the collection home for the collection "foo"
Collection home format is the format for collection home. This format must be human and machine friendly: one format covering both functionalities. It should be available in several language variants.
Collection list is the list of collections in the Open Data Portal.
Collection list URI is the URI that returns the collection list. Corollary: some collection identities could be reserved for the functioning of the Open Data Portal.
http://data.europa.eu/list
The Local should be mnemonic, compact, and as non-hierarchal as possible. Future versions of this document should futher specify the Local.
http://data.europa.eu/foo/34 # Publication "34" - non-hierachical - one segment local http://data.europa.eu/foo/2013/34 # Publication "34" of 2013 - hierarchical - two segments local http://data.europa.eu/foo/2014/34 # Publication "34" of 2014 - hierarchical - two segments local http://data.europa.eu/foo/14/34 # Publication "34" of 2014 - hierarchical - two segments local http://data.europa.eu/foo/14/m5 # Publication "m5" of 2014 - hierarchical - two segments local http://data.europa.eu/foo/14m5 # Publication "m5" of 2014 - non-hierarchical - one segments local
The number of local segment(s) is the number of path segment(s) minus one.
Collection Registrar is the entity with the mandate to allocate collections to Local Minters. There is only one Collection Registrar.
Local Minter is an entity with the mandate to mint locals for its collection. Corollary: minting a local means minting a URI. There are many Locals Minters.
Committees and similar entities:
The following should be addressed:
http://data.europa.eu/foo/bar # get the resource "bar" http://data.europa.eu/foo/bar? # get the metadata of the resource "bar"
[[!RFC3986]]
A Uniform Resource Identifier (URI) is a compact sequence of characters that identifies an abstract or physical resource.
the subset of URIs that, in addition to identifying a resource, provide a means of locating the resource by describing its primary access mechanism (e.g., its network "location").
The generic URI syntax consists of a hierarchical sequence of components referred to as the scheme, authority, path, query, and fragment.
foo://example.com:8042/over/there?name=ferret#nose \_/ \______________/\_________/ \_________/ \__/ | | | | | scheme authority path query fragment | _____________________|__ / \ / \ urn:example:animal:ferret:nose
This specification does not limit the scope of what might be a resource; rather, the term "resource" is used in a general sense for whatever might be identified by a URI. Familiar examples include an electronic document, an image, a source of information with a consistent purpose (e.g., "today's weather report for Los Angeles"), a service (e.g., an HTTP-to-SMS gateway), and a collection of other resources. A resource is not necessarily accessible via the Internet; e.g., human beings, corporations, and bound books in a library can also be resources. Likewise, abstract concepts can be resources, such as the operators and operands of a mathematical equation, the types of a relationship (e.g., "parent" or "employee"), or numeric values (e.g., zero, one, and infinity).
Each URI begins with a scheme name that refers to a specification for assigning identifiers within that scheme.
The authority component is preceded by a double slash ("//") and is terminated by the next slash ("/"), question mark ("?"), or number sign ("#") character, or by the end of the URI.
The path component contains data, usually organized in hierarchical form, that, along with data in the non-hierarchical query component, serves to identify a resource within the scope of the URI's scheme and naming authority (if any). The path is terminated by the first question mark ("?") or number sign ("#") character, or by the end of the URI.
A path consists of a sequence of path segments separated by a slash ("/") character.
The query component contains non-hierarchical data that, along with data in the path component (Section 3.3), serves to identify a resource within the scope of the URI's scheme and naming authority (if any). The query component is indicated by the first question mark ("?") character and terminated by a number sign ("#") character or by the end of the URI.
The fragment identifier component of a URI allows indirect identification of a secondary resource by reference to a primary resource and additional identifying information. The identified secondary resource may be some portion or subset of the primary resource, some view on representations of the primary resource, or some other resource defined or described by those representations. A fragment identifier component is indicated by the presence of a number sign ("#") character and terminated by the end of the URI.
[[!RFC2616]]
A network data object or service that can be identified by a URI. Resources may be available in multiple representations (e.g. multiple languages, data formats, size, resolutions) or vary in other ways.
The mechanism for selecting the appropriate representation when servicing a request, as described in section 12. The representation of entities in any response can be negotiated (including error responses).
A resource may have one, or more than one, representation(s) associated with it at any given instant. Each of these representations is termed a 'variant'. Use of the term 'variant' does not necessarily imply that the resource is subject to content negotiation.
A list containing variant descriptions, which can be bound to a transparently negotiable resource.
A machine-readable description of a variant resource, usually found in a variant list. A variant description contains the variant resource URI and various attributes which describe properties of the variant.
A resource from which a variant of a negotiable resource can be retrieved with a normal HTTP/1.x GET request, i.e. a GET request which does not use transparent content negotiation.
A list response returns the variant list of the negotiable resource, but no variant data. It can be generated when the server does not want to, or is not allowed to, return a particular best variant for the request.
[[!COMURI]]
0-9" "a-z" "-_."0-9" "a-z"-_"."/,
php,
jsp,
asp or
cgi.?";
i.e.,
without data.
The function is obtaining the
URI metadata.