| Version 16 (modified by , 12 years ago) ( diff ) |
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UUID conventions
General
All records in Sahana Eden which shall be shared with other instances or applications must have a universally unique identifier (UUID).
In Sahana Eden, these record UUIDs must be ASCII strings.
Eden automatically generates a UUID for each record according to the specifications in RFC4122:
All record UUIDs generated by Sahana Eden are strings in URN notation:
urn:uuid:a46c1b3b-35c0-44c6-9142-bbe3a013039a
If a record is imported into Sahana Eden and it already has a UUID, then Eden will retain this UUID as-is (exception: local domain prefix, see below) - without any syntax validation (i.e. no specific UUID schema is required). However, for consistency reasons, we recommend to use URNs.
Some data formats (e.g. PFIF) may require a domain prefix for a UUID, followed by a slash:
sahanafoundation.org/urn:uuid:a46c1b3b-35c0-44c6-9142-bbe3a013039a
Where such a domain prefix is used and it matches the local domain of the importing Sahana instance, it will be removed during import.
Mapping
We need an agreed set of UUIDs for GIS Data so that we can share data more easily across systems, such as the current Pakistan data
- OpenStreetMap IDs can change over time if records are deleted/recreated
- They can hold additional uid/uuid fields though
- Geonames data isn't free enough for OSM: http://wiki.openstreetmap.org/wiki/Geonames
- Geonet can be: http://wiki.openstreetmap.org/wiki/GEOnet_Names_Server
- Yahoo WoE data is in the public domain:
- Ushahidi doesn't have a common set of IDs across instances
- No space for a UUID either?
- Longer-term we need a common central repository of UUIDs that is held for the common good.
- Propose that Sahana start this off & then give up ownership/branding later:
- Sahana can use UUIDs of format: http://geo.sahanafoundation.org/<ID>
- These are associated with an OSM ID & Geonames ID for cross-correlation
- The Source ID field shows the source, so that OSM export can filter out sources like Geonames
- IDs from Ushahidi instances can be appended to the comments field in Sahana
