Unstructured changes

Adds an unstructuredChanges array to the Amendment object.

Guidance

In many procurement regimes, it is common to amend a procurement notice by describing the changes in words, rather than by re-publishing the full notice. This is because the process is designed for humans: it is easier for a human to read a description of changes, than to calculate the difference between two full notices.

On the other hand, it is easy for a machine to calculate the difference between two full notices, but difficult or impossible to interpret a description of changes. There are many ways in which a change description can go wrong, which a human can recover from, but which a machine cannot. For example:

• The label of the field that is subject to modification can refer to:
  • a label that doesn't occur on the earlier notice
  • an incorrect or imprecise label on the earlier notice
• The data type of the new value can be inconsistent with the data type of the field.

OCDS is designed to be read by machines. Ideally, the source system from which OCDS data is exported contains the values of each field before and after a change. In that case, you should simply follow the releases and records model.

This extension is intended to be used only in cases where a source system doesn't track the values of fields, but instead tracks a description of changes, like in the EU (see Legal context below). Note: The lack of structure prevents much data analysis.

Legal context

This extension was developed primarily to enable the mapping of the European Union's standard forms for public procurement to OCDS (specifically Form 14 Corrigendum), but it might be useful in non-EU contexts.

See OCDS for the European Union for guidance on how to use it with TED F14 data.

Example

{
  "tender": {
    "amendments": [
      {
        "id": "1",
        "unstructuredChanges": [
          {
            "oldValue": {
              "text": "https://city.example.org/procurement"
            },
            "newValue": {
              "text": "https://procurement.example.org"
            },
            "where": {
              "section": "I.1",
              "label": "Main address"
            }
          },
          {
            "oldValue": {
              "date": "2020-12-15"
            },
            "newValue": {
              "date": "2019-12-15T14:00:00+03:00"
            },
            "where": {
              "section": "I.4",
              "label": "Notice date"
            }
          },
          {
            "oldValue": {
              "classifications": [
                {
                  "scheme": "CPV",
                  "id": "79000000"
                }
              ]
            },
            "newValue": {
              "classifications": [
                {
                  "scheme": "CPV",
                  "id": "79822500"
                }
              ]
            },
            "where": {
              "section": "II.2.2",
              "label": "Main CPV code"
            },
            "relatedLot": "lot-2"
          }
        ]
      }
    ]
  }
}

Issues

Report issues for this extension in the ocds-extensions repository, putting the extension's name in the issue's title.

Changelog

2020-09-16

• Add Guidance section

2020-07-13

• Relax date format to allow either date or datetime

2020-06-04

• Review normative and non-normative words.

2020-04-24

• Add minProperties, minItems and/or minLength properties.

This extension was originally discussed as part of the OCDS for EU profile and in pull requests.