This page is non-normative, which means that it doesn’t form part of the standard; if there is any ambiguity, the standard takes precedence. This page may be updated at any time in response to community demand.
HSDS provides a common core for describing services, and includes a range of common fields, many of which are optional.
However, service provision is usually local, and so in a particular context there’s likely to be fields that aren’t relevant, and information that’s important but isn’t included in HSDS.
HSDS doesn’t have a formal extension mechanism, but does suggest several patterns in which communities wanting to share information among themselves can use HSDS as a starting point
Using the “constrain” pattern, a community can decide on certain fields or tables to not use at all.
Using the “extend” pattern, a community can decide on a common approach to including information that the schema doesn’t accomodate.
If a community chooses to extend the standard, then we encourage them to share their work with the wider OpenReferral community so that others facing similar issues can learn from them and provide feedback.
Constrain & Extend
The “constrain & extend” pattern combines the two previous patterns.
When extending, implementations should try to follow the design of HSDS as closely as possible.
If a field exists that’s close to one that you need, then it’s better to use it and describe how it’s used in your documentation.
Engaging the Community
The Open Referral community includes many people who’ve used HSDS in a range of contexts, from developing national ecosystems for sharing data, to deploying simple systems for use in low-tech community environments. They’re always happen to share their experience.
Developing the Standard
Extending the standard is a way to try out potential changes to the standard, so extensions play an important part in preparing for future releases.