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PyWPS is used to communicate all the necessary information to the presentation tier. This python open-source implementation of the OGC WPS protocol makes use of owslib and GDAL libraries to retrieve data values via WCS with the GeoServer instance that holds the layer data. For the expert mode, PyWPS queries a PostgreSQL/PostGIS database in order to obtain the XBeach wave propagation results for the sites. XBeach is a two-dimensional community driven model for wave propagation, long waves and mean flow, sediment transport and morphological changes of the near shore area, beaches, dunes and back barrier during storms.
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2.3 Data tier (GeoNetwork, GeoServer and PostGIS)
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