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_pages/create/transforms.md

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 title: Transforms
 permalink: /create/transforms
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+
+Transformations may be required for several reasons:
+
+1. To test the ability of a building block to model information from a particular source (that does not conform to the building block specification).
+
+Accordingly, different types of transformations may be required:
+
+1. Encoding translations (e.g. XML -> JSON)
+2. Schema transformations
+3. Semantic transformations (entailments, equivalent terms)
+4. Content transformations (terminology)
+
+**Note that the Building Blocks viewer application is still being developed to show all types of transformation in appropriate places.**
+
+## Transformation tools
+
+Building Blocks are technology agnostic, however rich support exists for JSON Schema and JSON-LD/RDF:
+
+- SHACL (AF- advances features) SPARQL rules are powerful for schema, semantic and content transformation rules.
+- JQ may be used for pure JSON transformations
+
+Custom code may be used for transformation and validation. (details TBD) 
+
+## Examples
+
+A key example is the mismatch between the GeoJSON geometry model and the GeoSPARQL geometry model. This
+requires the transformation of both structure and vocabulary to convert GeoJSON to valid GeoSPARQL - see this [example](https://ogcincubator.github.io/bblocks-examples/bblock/ogc.bbr.examples.feature.geosparqlFeature)
+
+The transformation specification is here:
+
+https://github.com/ogcincubator/bblocks-examples/blob/master/_sources/feature/geosparqlFeature/bblock.json#L17
+
+## Technical Documentation
+
 TBD