...

1. Username---*Present in RDF as well, this is the common key.  Since it is the permanent description of a user this is *{*}immutable*.
2. Password---Only in RDBMS.
3. Membership in Superuser role.  No other roles.

...

An Administrator (superuser)  can become documented by logging in, and either running the /whoami service with create=true or using the Admin UI to edit their own user info and saving it. An Administrator can fix an ordinary undocumented user by using the Admin UI to save their descriptive metadata; even if it is all blank, a user record will be created.  Importing users also straightens out the mapping automatically.

About Roles

Roles are  are a way to characterize a group of users, for example,   to grant them some access rights in the access-control system.   Functionally, the role is part of a user's authentication, i.e., "who" they are.
A role is defined by a URI, the subject of a :Role instance. It should also have a locally unique, short text-string name (the rdfs:label of its :Role instance). 

Each Role is independent of other Roles.  Roles cannot be "nested".  __ _This is a _necessary limitation that simplified the implementation considerably. 

The Superuser role is built into the system because its privileges are hardcoded.

...

This is just an outline of the access control system.   It is implemented as statements stored in the internal metadata graph.   The access controls applying to an instance or other object are not to be directly visible in the repository API, execpt through administrative UI. 

These types of access can be granted:

• Read---in context of named graph, allows the graph to be included in dataset of a query; for workflow transitions and hidden/contact property groups, this is the only relevant access grant.
• Add---add triples to a graph or instance.
• Remove---remove triples from a graph or instance.
• Admin---change the access controls on a resource. (Not really used in practice; only the Superuser role can change access.)

...

• Named Graphs, including workspaces.
  • Read lets people download and run queries against the graph.
  • Add, Remove let lets you modify it with /graph - this is usually Usually reserved for admins.
• Resource Instances (ignores explicit Read access; that comes from it's home named graph.)
  • Add, Remove let you modify it with /update, this is usually granted temporarily to a specific user as part of the workflow process.
  • ignores Read grants,  read access reverts to its home graph.
• Property Groups - sets of properties on a resource instance identified by statements in the data model ontology, see the data model configuration manual, particularly datamodel.hideProperty.predicate, datamodel.hideProperty.object.
  • Read lets the Dissemination and Harvest service report on these properties.
  • All other access types are ignored.
• Workflow Transitions
  • Read gives access to take (push) the transition.
  • All other access types are ignored.

Access control statements  grant access to either a specific user, or to a Role, which applies to all users holding that role.

...

Access control is implemented by statements of the form: 

• Subject:* resource, Predicate: access-type,

...

• Object: accessor

The resource is the URI of the instance, named graph, or workflow transition of interest.   The access-type names one of the four types of access described above: read, add, remove, admin.   Finally, the accessor  is the URI of the Principal to be granted the access, either a Role or an Agent (user).

We anticipate having a relatively small number of these access grants.   Although named graphs and workflow transitions need elaborate access descriptions, there are only a few of those -- on the order of dozens.   Resource instances are of course more numerous but most of them have no access grants, deriving their read/query access from the named graph they reside in.   The workflow claim service adds temporary grants to give the claim owner read/write access to be able to edit the instance while it is claimed.

...

The repository automatically records provenance metadata about objects when they are created and modified by users' actions.   Provenance means information about the history and origin of the data, in this case the authenticated identity responsible and time of the latest change. The following properties are recorded for these types of objects, and can be obtained by querying with a view or dataset that includes the named graph containing public administrative metadata.

Note that the there is at most one value of any of these properties for each subject.   That means the "modified" properties are updated whenever a subject is modified and the record of the previous modification is lost.   This is a simplification that may be remedied at some point in the future if we add versioning of data to the repository.

• Named Graphs:
  • dcterms:modified - literal date of last modification, encoded as xsd:dateTime
  • dcterms:contributor ---the URI of the Agent (authenticated user) who last modified it  it
  • dcterms:source ---description of file or URI last loaded into this NG, if that is how it was created.  This record is used to compare it against the source later to decide whether an updaet is necessary. It is a node (possibly blank node) with the following properties:
    • dcterms:identifier ---the resolvable URI of the resource loaded, most likely a URL in either the file or http scheme.
    • dcterms:modified ---last-modification date of the resource, for later comparison when deciding whether to decache the repository copy of an external file, a literal xsd:dateTime.
• Resource Instance:

  • Wiki Markup
    *dcterms:created* \---literal date when resource was created, encoded as \[xsd:dateTime

    <ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="ab62d9ed-4023-470c-94ec-99f74a083580"><ac:plain-text-body><![CDATA[

    [http://www.google.com/url?q=http%3A%2F%2Fwww.w3.org%2FTR%2Fxmlschema-http://www.google.com/url?q=http%3A%2F%2Fwww.w3.org%2FTR%2Fxmlschema-2%2F%23dateTime&sa=D&sntz=1&usg=AFrqEzfRDUuCfWjkGIj5ZuqOGGVPGBo7ZQ]]

    ]]></ac:plain-text-body></ac:structured-macro>

    • Set automatically by the Repository.
  • dcterms:creator ---the URI of the Agent (should be an auth'd user) who created teh instance.
    • The true meaning is the user who authored the data in the inital version of tihs instance.
    • Usually, this is the same as the user directly responsible for creating the instance.
    • However, when a different user uploads e.g. a spreadsheet created by other RNAVs, the Repository user is a mediator.   The actual value of dcterms:creator comes from the uploaded data.
  • (optional) dcterms:mediator - ONLY when dcterms:creator does not refer to the authenticated user who created the data, this is the URI of the Agent (authenticated user) who created this instance in the Repository.
    • Set automatically by the Repository.

  • Wiki Markup
    *dcterms:modified* \---literal date when resource was last modified, encoded as \[xsd:dateTime

    <ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="5c23d771-6214-4705-a120-fe35849d8fc3"><ac:plain-text-body><![CDATA[

    [http://www.google.com/url?q=http%3A%2F%2Fwww.w3.org%2FTR%2Fxmlschema-2%2F%23dateTime&sa=D&sntz=1&usg=AFrqEzfRDUuCfWjkGIj5ZuqOGGVPGBo7ZQ]]

    ]]></ac:plain-text-body></ac:structured-macro>

    • Set automatically by the Repository.
  • dcterms:contributor ---the URI of the Agent (authenticated user) who last modified this instance.
    • Set automatically by the Repository.

...

Some repository features are implemented as extensions to the Sesame RDF database (aka triplestore).   This means they are available both internally to the repository implementation and externally whenever an API to Sesame (e.g. its SPARQL query engine) is exposed.

...

Additional output formats for both RDF serialization and SPARQL tuple query results allow output in:

• *HTML,   *media type text/html
• *plain text,    *media type text/plain (for SPARQL)
• N-Quads, RDF only, for comparing serialized RDF including context (graph).

2. SPARQL Query Function

The  repo The repository adds a custom function to Sesame's query engine: repo :upperCaseStr.   It returns the toUpperCase() version of of hte the string value of an RDF value.   Use it to sort values ignoring  whether (a) the case of characters differs, (b) they are datatyped-literals or untyped literals (or other terms).

To invoke it you must have the repository's URI namespace defined as a
prefix, e.g.  

 PREFIXrepo:<[http://eagle-i.org/ont/repo/1.0/

...

]>   ..query text...

...

 ORDER BYrepo:upperCaseStr(?label) 

Workflow

The repository includes a "workflow" control system that directs the complete lifecycle life cycle of each resource instance, and mediates access by users at each lifecycle life cycle stage.   The word "workflow" is often used to describe process-management and administration systems, but in this case it is really just a minimal implementation of states and extended access control.

It was implemented in the repository because it depends on persistent data and access control which are already available in the repository.   It is also closely integrated with the access control system, which is easier to accomplish securely from within the repository codebase.

Workflow is manifested in   RDF statements (of course) in the internal metadata graph.   Although the Web API exposes some URIs and names of workflow objects, the ontology and access control details are intentionally hidden.   There is no need for applications using workflow to see the model, all their access is through the API.

The model is a state map, with nodes and transitions between them.   elements Elements of workflow are:

1. Workflow State---A node on the state map.  Every resource instance has exactly one current state.  A newly created resource is initialized to a fixed "New" state.
2. *Transition---*Description of an arc on the map, or a transition from an initial state to a final state.
3. *Claim---*Assertion on a resource instance that a specific user (the claimant) has taken possession of it, in order to prepare it for the next workflow transition.  
   • Claiming typically causes some side-effects such as changing access controls. 
   • A claim may be resolved by taking a transition to another state, or by releasing it.
4. Pool---The set of resource instances available for claiming to a specific user.   A pool is always computed by a query, it is not materialized.

Bootstrapping and Configuration

Bootstrapping refers to how a new repository node first starts up. The process is not trivial, since so much of its operation depends on the RDF database (triple-store, actually a quad-store) which is completely empty when a new repository is launched.

The repository must be simple (ideally "foolproof", although that only breeds more destructive fools) to install and manage, since it is intended to be deployed at dozens or hundreds of sites, managed by administrators with varying experience levels.  Al the while, it must still maintain adequate security and data integrity.

The bootstrap process:

1. Install the webapp by dropping the WAR file into place, and adding configuration:
   1. Add one system property to the Web server's JVM to indicate the configuration properties
   2. Create configuration properties file with at least the minimum required properties.
2. Create authentication DB and add the initial Administrator user.
3. Start the servlet container---the repository webapp automatically initializes the following named graphs if they are found to be empty:
   1. The internal Repository ontology (read-only)
   2. Internal Repository administrative metadata (e.g. Roles, Named Graphs, WF Transitions, etc.)
   3. SPARQL Query macros.
4. Create an RDF metadata wrapper for the initial adminstrator user - this is done automatically by the post-install procedure, finish-install.sh. See Admin Guide for Data Repository
5. Load the eagle-i data model ontology.  Although this is not necessary for any of the Repository's internal functions, the eagle-i apps will expect it to be there.
6. Browse to the Admin UI and log in as the Administrator user. You can create user logins and assign roles; modulo any customizations of workflow, workspaces and such. With that, the repository is open for business.

Configuration properties

The configuration properties are loaded from the file configuration.properties in the repository home directory. It is read by Apache Commons Configuration, which allows system properties and other variables to be interpolated into the values. See the Apached Web site for complete documentation.

See the Configuration section in the Administrator Guide for a complete list of configuration properties.

Basic Repository REST API

These are the possible HTTP requests in the repository API.

Webapp Mount Point

The repository's webapp must be mounted at the web server's root, so that it can resolve the canonical URI of resource data instances.

Format Identifiers and MIME Types

This section lists the formats that the repo can use for output and, in some cases, input, of data. The MIME type is how you describe it in the API, whether through explicit args or HTTP headers.

In a request, you can usually specify input format in two ways:

Explicitly through the format arg, which takes precedence.
As the HTTP Content-Type header on the request body or arg entity (this only takes precedence in a request like /update which has multiple text entities with a possible content-type)

You can ask for an output format in two ways as well:

Explicitly through the format arg, which takes precedence.
As the HTTP Accept header in the request headers, which may be a list of formats and qualifiers; the repo implements full HTTP 1.1 content negotiation.

Note that the tabular (tuple) and boolean query result formats are output-only. There are no requests that take them as input formats.

RDF Serialization formats:

    
¹ The Context-NTriples format is not an official RDF serialization; it was added for this repository, as a convenient way to export quads for testing. Note that it was formerly named NQuads, but there is already a different unofficial format known to the RDF community that is called "NQuads".
² This format only supports output, it cannot be read by the repository.
^3^HTML is for interactive viewing only, it cannot be parsed.

Tuple (Tabular, SPARQL SELECT) Query Result Serialization formats:

Boolean Query Result Serialization formats:
Name Symbol Default MIME type
Additional MIME types
SPARQL/XML SPARQL application/sparql-results+xml
TEXT TEXT text/boolean

Identify and/or "Create" Current User (/whoami)
Returns a tabular report on the current authenticated user's identity to e.g. compose a friendly display in a Web UI. This is really just a SPARQL query wrapped in a servlet to hide the details of the internal data.

This request can also function as a "login" mechanism to establish a session and cache authentication, while at the same time getting the user's displayable name to show in the UI.

Subtle Alternate Function: Note that the POST form of this request has a separate function when create=true: It creates the RDF metadata for a login user account. Normally this is only done as part of the initial bootstrap procedure, by the finish-install.sh script. When users are created through the Admin UI or /import their RDF metadata is created automatically.

NOTE: Perhaps it would be better to implement this as a redirect to the resolvable URI for the person, which would then yield a description compatible with the FOAF standard. That's how the Semantic Web wants us to manage it.

URL: /repository/whoami (GET, POST)

Args:
format - same as for SPARQL result format, same default (SPARQL XML)
create=(true|false) - when true, invokes alternate function of this service to create RDF metadata for current user (see explanation above).
firstname=text - ONLY when create=true, the first name value of the created User instance (optional).
lastname=text - ONLY when create=true, the last name value of the created User instance(optional).
mbox=text - ONLY when create=true, the mbox value of the created User instance(optional).

GET Result:
Response document is a SPARQL tuple result, format determined by the same protocols as for /sparql. It contains the following columns:

uri - resolvable URI of the :Agent instance for this person if any (see below).
username - short user name as given to the login process
firstname - user's first (given) name, and middle names if any
lastname - user's last (family) name
mbox - user's email address

Note that the last 3 fields may be empty if that data is not available.

If there is no :Agent instance for the logged-in user, the URI will revert to their implicitly asserted Role, e.g. :Role_Superuser for an administrator. This is the same URI that appears in provenance metadata entries like dc:creator.

POST Result:
When create=true, the result document is empty, and the status code indicates success:

201 when a new User instance was successfully created.
409 (conflict) when a User instance already exists - THIS SHOULD BE CONSIDERED SUCCESS!
Any other code indicates failure.

Access:
Open to authenticated users.
Create New Instance Identifier(s) (/new)
This call creates one or more globally unique, resolvable, URIs for new resource instances. It does not add any data to the repository; the instances will not exist until a user inserts some statements about them. The URI namespace is the default namespace from the configuration properties, followed immediately by the unique identifier. Note that ETL tools may request thousands of URIs at once so the mechanism to produce unique IDs must be able to handle that.

URL: /repository/new (POST only)

Args:
count - number of URIs to return; optional, default is 1.
format - same as for SPARQL result format, same default (SPARQL XML)

Result:
The requested number of new URIs are returned, packaged as a SPARQL query result for a field named "new". Its encoding is determined by the format parameter or, if none specified, by the Accept header of the HTTP request. Default is SPARQL/XML.

Access: Requires an authenticated user.
Disseminate Instance (/i, /repository/resource)
The disseminate service returns the RDF content of an instance; it is how the URI is resolved to implement the Linked Open Data paradigm of the Semantic Web. Note that there are actually three valid ways to construct a request for any given data instance:

/i/instance-ID - assumes that URI prefix matches Web server's DNS address (i.e. the configured default URI namespace).
/i?uri=instance-URI - retrieves any instance URI whether the prefix matches the default namespaec or not. This allows one repository to resolve multiple domains.
/repository/resource?uri=instance-URI - Just like hte /i form, only with authentication required. This is the recommended URL for programs accessing resource contents through the REST API, since /i might not require or make use of authentication credentials.

URL: /i/instance-ID (GET or POST method)
/i
/repository/resource

Args:
uri =uri - optional, only if URI not specified as the tail of the request URI; an alternate way to explicitly specify the complete URI of the resource to disseminate. Allows any URI to be accessed, instead of assuming that the URI's namespace matches the hostname, context, and servlet path ("/i") to whcih the repo's webserver responds.
format=mimetype - optionally override the dissemination format that would be chosen by HTTP content negotiation. Note that choosing text/html results in a special human-readable result.
view=view - optionally choose a different view dataset (see Views in concepts section) from which to select the graph for dissemination. Mutually exclusive with workspace.
workspace=uri - URI of the workspace named graph to take the place of the default graph. Relevant metadata and ontology graphs are included automatically. Mutually exclusive with view.
noinferred (boolean) - Exclusde all inferred statements from the generated results. This really only applies to rdf:type statements; if the noinferred query argument is present (it need not have any value) then inferred types are left out of the results.
forceRDF (boolean) - forces a result of serialized RDF data. When the negotiated result format is text/html, the usual choice is to geneate the human-readable view. This forces an HTML rendering of the RDF statements whcih can be handy for troubleshooting, especially when combined with noinferred. NOTE: This is the only way to see the Embedded Instance statements in an interactive HTML view, e.g. in a web browser, so it is especially handy for generating a clean view for debugging EIs. Default false.
forceXML (boolean) - when an HTML format would be generated, output the intermediate XML document instead of transforming it to XHTML. This is mainly useful for obtaining examples of the intermediate XML for developing new XSLT stylesheets and testing/debugging. Default is, of course, false.

Result:
Returns a serialization, or, optionally, human-readable HTML renderign, of the graph of RDF statements describing the indicated resource instance. Note the deliberate choice of words: This graph includes not only the statements of which the URI is the subject, but also:

Statements describing Embedded Instances in the resource instance, for the same meaning of "describing" (but note that EIs are not recursive, an EI may not have its own EIs.)
Statements about the "Label" properties of all predicates and object-property values of the instance and its EIs. (The exact set of properties used for "label" is configurable.) See the SWAG page for more about label properties.
Provenance and some administrative metadata about the instance.

Note that depending on the authenticated roles of the requesting user and the configured access controls, some properties may be excluded from this result. For example, in some cases, unauthenticated users will not see certain properties which may contain confidential information.

About HTML dissemination:
When the negotiated format is text/html, and unless either of the forceRDF or forceXML args was given, the dissemination process creates an intermediate XML document and transforms it into XHTML with the configured XSLT stylesheet. (See description of the eaglei.repository.instance.xslt in the Admin Guide.)

If no XSLT stylesheet is configured, the intermediate XML document is delivered instead, with a media content type of application/xml. Note that this means, to obtain correct XHTML output, you MUST configure an XSLT stylesheet.

The content of the intermediate XML format is described in a W3C XML Schema document that may be downloaded from a running repository at e.g.https://localhost:8443/repository/schemas/instance.xsd

We provide an example transformation stylesheet that produces very simple HTML, intended to be the basis of custom stylesheets. It is available for download at e.g.:https://localhost:8443/repository/styles/example.xsl

We manaeg the transformation within the repository, instead of adding an xml-stylesheet processing instruction to the XML, for compelling reasons:

Client-side transformation is a relatively new concept and we cannot trust it to be implemented reliably and consistently.
Some user agents, such as Web crawlers, depend on receiving true HTML content and so they should not be given XML. This might be determined by content negotiation but we do not expect that to be reliably implemented either.
Some aspects of the transformation depend on parameters in the stylesheet (see below) that are supplied at run-time from repository configuration values.

The transformation stylesheet is supplied with these parameters when it is invoked. They should be declared with <xsl:param name="..."/> directives in the XSL. Be sure your stylesheet can cope with parameters that are not set, by supplying default values.

__repo_version - string containing Maven version spec of the running repository code. This is always set.
__repo_css - configured value of eaglei.repository.instance.css, may not be set.
__repo_logo - configured value of eaglei.repository.logo, may not be set.
__repo_title - configured value of eaglei.repository.title, may not be set.

Property Filtering
The set of properties returned in the HTML view is based on the same result as RDF disseminations, which is automatically filtered as necessary for the requesting user's access level.
Access:
Requires read permission on all named graphs in the query's chosen view. Note that this is the ONLY service available to unauthenticated users, so it must be able to gather a useful result from named graphs readable by the Anonymous role. If you do access this service with credentials, you will be able to see instances and properties that would be invisible to an unauthenticated user, e.g. instances in private workspaces that are still in unpublished workflow states.

Note that when the requesting user does not have read access to the requested instance, it will appear to him/her that it does not exist; the error returned is identical to one for a nonexistent resource, since it is essentially the same case.

There is also access control on some indivdual properties of the resource: those properties identified as hidden and contact properties by the data model ontology (and its configuration, see that separate document). The access controls on the resource URI configured as datamodel.hideProperty.object regulate hidden proerties, and datamodel.contactProperty.object regulates contact properties.

Anyone with READ access on the URI gets to see the properties, so e.g. to expose them to the world you'd give access to the Anonymous role. Normally only Curator, RNAV, and Lab User roles would be granted access to hidden and contact properties since they have to see and manipulate them through the dta tools.
Update a Single Instance (/update)
This service actually implements three different kinds of request:

Create a new resource instance (including embedded instances) - must specify its home graph.
Obtain the edit token with which to modify an existing resource instance.
Modify ("update") the properties of a resource instance, both delete and add in one transaction. This includes adding, deleting, and modifying any embedded instances.

Update operation does all its work in the instance's home named graph. For an existing instance being modified, it is computed as the named graph in which the asserted rdf:type statement(s) are found.

When creating new resources: Since the create operation hasn't got an instance from which to derive its home graph, its home graph must be specified as the workspace arg.

Workflow Implications of Creating New Resources: Since the /update action that creates a new resource instance is effectively performing a transition from the New workflow state, the current user must have permission to make such a transition to the destination workspace; if there are multiple transitions, one is chosen arbitrarily.

On the Acquiring and Use of Edit Tokens: The edit token is intended to "protect" the read-only copy of the instance that you (presumably) download as a basis for edits. The correct sequence of operations when modifying an instance is:

Obtain the edit token.
Get RDF for the resource instance.
Submit an /update request to modify the resource instance, with token (1).

This ensures that no matter how much time passes between (2) and (3), e.g. if a user dawdles over an interactive edit or forgets and leaves it overnight, the edit token is already in place to indicate his/her intention to make a change. It does not prevent another user from coming along and grabbing the token to make a change, but it will indicate that there is an edit in progress, and it will prevent a stale copy from being checked in.

Comparison with SPARQL/UPDATE: In case you are wondering why we chose to implement this complex special-purpose service instead of a general protocol like SPARQL/UPDATE - there were some compelling reasons:

Too difficult to impose the necessary fine-grained access controls on SPARQL/UPDATE. This service is defined to be a transaction that only affects one resource instance (and its embedded instances).
Major benefit of S/U protocol is accepting a list of deletes and a list of inserts, which we do here.
SPARQL/UPDATE is still not a recognized standard, and implementations are poor.

When action=create, there must be no existing statements in the repo with the given URI as a subject. The request must include an insert arg containing one or more statements whose predicate is rdf:type. (All of the subjects must match the request URI). It is an error to specify a delete arg.

When action=gettoken, an edit token is created if necessary, and returned along with the user who created it, time it was created, and a boolean value that is true if it was newly created by this request. This information is intended to help a UI service advise the user when there might be an edit in progress, i.e. if the boolean was false and the timestamp on the token is recent.

When action=update, there must be an existing instance matching the URI of the request. DO NOT specify the workspace arg, since the repository automatically finds the instance's home graph and makes all changes there.

Updating a resource instance's properties requires an edit token. The token lets the server check that your edits are based on the current valid state of the resource; if another update occurs before yours, its changes could be corrupted or lost. To update, first, run the /repository/update request with the arg, action=gettoken to obtain the current edit token, creating one if necessary. Then, get the content properties as before. When calling /repository/update again with action=update add the token=token-uri arg.

Note on File Format and Character Set: The request specifies the file format and/or character set of the serialized RDF data as a Content-Type header value in the entity bodies of insert and delete args, e.g. text/rdf+n3; charset="ISO-8859-1". The character set defaults to Unicode UTF-8, so if your source data is not in that character set you must declare it. The content-type can be provided in two different places – they are searched in this order of priority, and hte first one found is the only one considered:

Content-Type header on the value of the content entity in a POST request. This takes precedence because it allows for different content-types in insert and delete args.
format query argument value.

URL: /repository/update \[ /instance-ID  \] (POST only)

Args:
uri - optional way to explicitly specify the complete URI, instead of assuming that the URI's namespace matches the hostname, context, and servlet path ("/i") of this webserver.
format - the default expected format for insert and delete graphs. If the args specify a content-type header, that overrides this value. Only recognizes triples even if the format supports quads.
action=(update|create|gettoken) - Update to modify an existing instance, create adds a new one. See below for details about gettoken.
token=uri - When action is update or create, this must be supplied. The value is the URI returned by the last gettoken request.
workspace=uri - Choose workspace named graph where new instance is created. Only necessary when action=create. Optional, default is the default workspace. DO NOT specify a workspace when action=update.
delete - graph of statements to remove from the instance; subject must be the instance URI. Deletes are done before inserts. Graph may include wildcard URIs in predicate and/or object to match all values in that part of a statement.
insert - graph of statements to add to instance; subject must be the instance URI.
bypassSanity - (boolean, default false, deprecated) - NOTE: It is best if you pretend this option does not exist. When true, it skips some of the sanity tests on the resulting instance graph, mostly the ones checking the integrity of Embedded instances. Requires Administrator privilege. This was added to make the data migration from broken old EI data possible, it should rarely if ever be needed now.

The delete wildcard URI is http://eagle-i.org/ont/repo/1.0/MatchAnything

Result:
HTTP status indicates success or failure. Any modifications are transactional; on success the entire change was made, and upon failure nothing gets changed.

When action=update is used to effect a change to a resource instance, this service automatically optimizes the requested change so the fewest actual statements are modified. For example, if the request deletes all statements by using the wildcard URI in the position of predicate and value, and then inserts all of the statements that were there before along with an additional new statement, the only change actually made is to add that new statement. Since a gratuitous change to an rdf:type statement results in extra time spent inferencing, it is best to avoid it when possible.

When an update fails because the edit token is stale, the HTTP status is always 409 (Conflict). If this occurs, the only solution is to get a fresh token and re-do the update. It is NOT advisable to have a client simply retry the update with the same data – at least inform the user that there has been an intervening edit and updating now would destroy somebody else's changes.

When action=gettoken, the response includes a document formatted (according to the chosen format) as a SPARQL tuple result. It includes the columns:

token - URI of the edit token. It has no meaning other than its use in an update transaction. This is the last edit token created (and not yet "used up" by an update) on this instance; or else a new one that was created if there wasn't one available.
created - literal timestamp at which the token was created. It may be useful to display the date to the user if there was an existing token of recent vintage.
creator - URI of the user who created the token
new - boolean literal that is true if this gettoken operation created a new token. when false, taht means the token already existed, which indicates there MAY already be another user's update in progress which might conflict with yours. (see the created and creator values)
creatorLabel - rdfs:label of the creator if available.

Access:
Requires ADD access to the either the instance itself or the its home named graph if the insert argument was given, and REMOVE access on the instance or the graph if the delete argument was given. When action=create, requires READ access on an appropriate Workflow Transition - out of the New state.

We may eventually decide to implement a quota on the count of statements that may be added or deleted, as a protection against DOS attacks and runaway clients.