BluePrint: Record Merger

Introduction

There are several occasions where records need to be merged manually, e.g.:

• De-duplication
• Synchronization conflict resolution

Description

The idea is to implement a generic merge method for the RESTful API, which responds to URLs like:

/xxx/yyyyyy/25/merge?with=27

• merge record 27 (=merge source) into record 25 (=original record)

Additionally, the low-level API could also accept a Storage of fields from the caller instead of another record.

Requirements

• GET merge returns a form like above:
  • the merge form behaves basically like a normal update form:
    • the user can edit the original record
    • the user can click on <<copy to copy values from the merge source

• POST merge does:
  • update the original record with the data of the form
  • update all links to the merge source into links to the original record
  • mark the merge source deleted (or delete it, if no deletion status)
  • audit update

• PUT merge does:
  • respond with "invalid method" (HTTP/405)

• DELETE merge does:
  • respond with "invalid method" (HTTP/405)

• Errors:
  • original record does not exist => HTTP/404 Not Found
  • merge source does not exist => HTTP/404 Not Found (or redirect to update?)

• Extensions:
  • provide a Copy All button to copy all values from the merge source
  • provide a Undo button to take back all changes
  • Use update_next for default redirection, or do we need a separate merge_next?
  • provide a Replace button to replace the original by the merge source:
    • basically just a link from /xxx/yyy/25/merge?with=27 to /xxx/yyy/27/merge?with=25

Use-Cases

• Primary actor:
  • admin user / editor user

• Merging of duplicate records in the de-duplicator
  • De-duplicator UI presents a list of possible pairs of duplicates: (original, duplicate)
  • List entries are linked to the merge method (action button)
• Merging of conflicting remote records in the synchronization conflict resolution UI
  • Conflict UI presents a list of conflicting updates: (original, conflicting update)
  • List entries are linked to the merge method (action button), or delete

Design

• Implement merge as a subclass of S3Method
• Implement a generic view merge.html (_merge.html) which:
  • renders the form

Implementation

• UserGuidelines/Admin/RecordMerging