Layer 1 Linked Data Platform Interface

Layer 1 operates as a Server in the Linked Data Platform protocol. It exposes a set of Linked Data Platform RDF Sources (LDP-RS) and Linked Data Platform Containers (LDPC) that provide clients with an interface for performing CRUD operations on MMS5 primitive objects. These objects include: orgs, projects, branches, locks, users, groups, roles, permissions and policies.

LDP Containers

• /orgs

  • GET - enumerates orgs

• /projects

  • GET - enumerates all projects user has access to

• /projects/{PROJECT_ID}/branches

  • GET - enumerates all branches within a project that a user has access to

• /projects/{PROJECT_ID}/branches/{BRANCH_ID}/commits

  • GET - enumerates all ancestor commits given the project and branch id

• /projects/{PROJECT_ID}/locks

  • GET - enumerates all branches within a project that a user has access to

LDP Resources:

• /orgs/{ORG_ID}

  • GET - returns 1-degree triples for the given org

  • PUT - creates a new organization

  • POST - modifies an existing organization

  • DELETE - deletes an existing organization

• /projects/{PROJECT_ID}

  • GET - returns 1-degree triples for the given project

  • PUT - creates a new project

  • POST - modifies an existing project

  • DELETE - deletes an existing project

• /projects/{PROJECT_ID}/branches/{BRANCH_ID}

  • GET - returns 1-degree triples for the given branch

  • PUT - creates a new branch

    • required triples: <#> mms:commit ?commit .

  • POST - modifies attributes of existing branch

  • DELETE - deletes an existing branch

• /projects/{PROJECT_ID}/locks/{LOCK_ID}

  • GET - returns 1-degree triples for the given lock

  • PUT - creates a new lock

  • DELETE - deletes an existing lock

Possible response codes:

• 200 - Success

• 201 - Resource created (response to PUT)

• 400 - Bad request, including but not limited to: non-RDF content-type, unsupported content-type, malformed RDF syntax

• 401 - Unauthorized

• 403 - Forbidden

• 404 - Not found

• 405 - Method not allowed

• 406 - Invalid Accept headers

• 412 - Precondition failed (reserved for conditional headers)

• 422 - RDF body of the request missing required triple(s)

• 5xx - Network errors communicating with the underlying triplestore, and wrapped non-2xx HTTP responses from the triplestore

Example: Creating a new branch

HTTP request sent from ‘client’ to Layer 1:

PUT /projects/TMT/branches/develop
Content-Type: text/turtle

prefix mms: <https://openmbee.org/rdf/mms/ontology/>
base <../../>
prefix mp-commit: <./commit/>

<#> a mms:Branch ;
  mms:commit mp-commit:e4a1c .

SPARQL query sent from Layer 1 to the triplestore:

prefix mms: <https://openmbee.org/rdf/mms5/ontology/>
prefix mms-datatype: <https://openmbee.org/rdf/mms5/datatype/>

base <https://example.org/mms5/>
prefix m-user: <./user>

base <./projects/TMT/>
prefix mp: <./>
prefix mp-branch: <./branches/>
prefix mp-commit: <./commits/>
prefix mp-graph: <./graphs/>

insert {
  graph mp-graph:Metadata {
    mp-branch:develop a mms:Branch ;
      mms:name "develop" ;
      mms:commit mp-commit:e4a1c ;
      mms:creator m-user:jdoe ;
      mms:created "2021-01-01T02:03:04.0506Z"^^xsd:dateTime ;
      mms:modified "2021-01-01T02:03:04.0506Z"^^xsd:dateTime ;
      .
    
    mp-snapshot:develop.e4a1c a mms:Snapshot ;
      mms:materializes mp-branch:develop ;
      mms:graph mp-graph:Model.develop.e4a1c ;
      .
  }
}
where {
  graph mp-graph:Metadata {
    filter not exists {
      {
        mp-branch:develop a mms:Branch .
      } union {
        ?branch a mms:Branch ;
          mms:name "develop" .
      }
    }
  }
};

move mp-graph:Staging_0.master.e4a1c to mp-graph:Model.develop.e4a1c ;

HTTP response returned from Layer 1 back to ‘client’:

201 Created
Content-Type: text/turtle

@prefix mms: <https://openmbee.org/rdf/mms/ontology/> .
@prefix mp: <https://example.org/mms/projects/TMT/> .
@prefix mp-branch: <https://example.org/mms/projects/TMT/branches/> .
@prefix mp-commit: <https://example.org/mms/projects/TMT/commits/> .

mp-branch:develop a mms:Branch ;
  mms:name "develop" ;
  mms:commit mp-commit:e4a1c ;
  mms:creator m-user:jdoe ;
  mms:created "2021-01-01T02:03:04.0506Z"^^xsd:dateTime ;
  mms:modified "2021-01-01T02:03:04.0506Z"^^xsd:dateTime .