Document Storage

Overview

Simplifying assumptions

• V1 won't have namespace support
• Path expressions limited to XPath syntax:
  • [n] - match nth child
  • [path='value'] - only element/attribute value equality
• POST:{path}
  • if path could resolve to multiple sub-trees, insertion happens at end of last
• PUT:{path-expression}
  • if expression has more than one matches, only the first one is affected
• DELETE:{path-expression}
  • f

Alternate approach

• Do not try to map path/filesystem to XPath semantics
  • In Xml a path does not necessarily refer to a single node
• A path has to uniquely identify a document fragment
  • use unique attribute/element mapping to generate unique path
    • i.e. /foo/bar:1234 map map to /foo/bar/@id
  • in lieu of a uniqueness mapping for a path, attach the DB element id as @id in a special namespace

Example

<acl>
    <users>
        <user id="1234>
            <name>Bob</name>
        </user>
    </users>
</acl>

Features