eXist Interface: User annotations

User annotations are maintained by the interface function /mpdl/interface/external/object.xql. This function has 3 parameters:

• operation (possible values: read, create, update, delete)
• type (possible values: element, query)
• object (see examples below)
  • attributes
    • uid: user id (normally email address) of the operation (e.g. andy@…)
    • documentId: the eXist document identifier (e.g. /tei/en/Test_1789.xml)
    • xpointer: the xpointer to the position in that document (e.g.: id('page2')/TEI[1]/text[1]/body[1]/p[1]/s[3]/point(4)); see XPointer specification; it consists of 3 parts:
      • page number: (e.g. id('page2'))
      • XPath identifier of the XML page node (e.g.: /TEI[1]/text[1]/body[1]/p[1]/s[3])
      • text point within that node (e.g: /point(4))
  • value: if operation is create or update: the new object (e.g. <note>This is an annotation of Andy</note>)

To maintain a user annotation "at the HTML side" one needs the XPath identifier of the XML page node at which the annotation should be created/updated/deleted. This identifier is displayed by the parameter "options=withXmlNodeIds" in the interface function /mpdl/interface/page-fragment.xql. Then the output HTML document page contains an additional attribute "xmlNodeId" in all HTML nodes which are XML nodes (e.g. <span class="s" xmlNodeId="/TEI[1]/text[1]/body[1]/p[1]/s[1]">This is the first sentence of the first paragraph.</s>)

Limitations

• Interface
  • Java: no real user test done
  • Display of a document page with external objects (insertExternalElements.xsl): full redesign and new implementation
• Bugs
  • at one position there could be only one external user annotation so far (bug in XSL script)

Open questions

• Versioning of annotations
• Discussion / Blog of each document page

Examples

Example document

• ​Test document: Display of page 1 with XPath identifiers for all XML nodes
• ​Test document: Display of page 2 with external user annotations

Read annotations

  http://mpdl-test.mpiwg-berlin.mpg.de:30030/mpdl/interface/external/object.xql?
    operation=read&
    type=element&
    object=<object documentId="/tei/en/Test_1789.xml" xpointer="id('page2')"></object>

​Read annotations

Create annotation

  http://mpdl-test.mpiwg-berlin.mpg.de:30030/mpdl/interface/external/object.xql?
    operation=create&
    type=element&
    object=<object uid="andy@mpiwg-berlin.mpg.de" documentId="/tei/en/Test_1789.xml" xpointer="id('page2')/TEI[1]/text[1]/body[1]/p[1]/s[3]/point(4)"><note>This is an annotation of Andy</note></object>

​Create annotation

Update annotation

  http://mpdl-test.mpiwg-berlin.mpg.de:30030/mpdl/interface/external/object.xql?
    operation=update&
    type=element&
    object=<object uid="andy@mpiwg-berlin.mpg.de" documentId="/tei/en/Test_1789.xml" xpointer="id('page2')/TEI[1]/text[1]/body[1]/p[1]/s[3]/point(4)"><note>This is an annotation of Andy</note></object>

​Update annotation

Delete annotation

  http://mpdl-test.mpiwg-berlin.mpg.de:30030/mpdl/interface/external/object.xql?
    operation=delete&
    type=element&
    object=<object uid="andy@mpiwg-berlin.mpg.de" documentId="/tei/en/Test_1789.xml" xpointer="id('page2')/TEI[1]/text[1]/body[1]/p[1]/s[3]"></object>

​Delete annotation