Extract facet code out into a new plugin hook, closes #427 (#445)

Datasette previously only supported one type of faceting: exact column value counting.

With this change, faceting logic is extracted out into one or more separate classes which can implement other patterns of faceting - this is discussed in #427, but potential upcoming facet types include facet-by-date, facet-by-JSON-array, facet-by-many-2-many and more.

A new plugin hook, register_facet_classes, can be used by plugins to add in additional facet classes.

Each class must implement two methods: suggest(), which scans columns in the table to decide if they might be worth suggesting for faceting, and facet_results(), which executes the facet operation and returns results ready to be displayed in the UI.
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Simon Willison 2019-05-02 17:11:26 -07:00 committed by GitHub
commit ea66c45df9
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10 changed files with 600 additions and 132 deletions

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@ -3,7 +3,11 @@ import pluggy
import sys
from . import hookspecs
DEFAULT_PLUGINS = ("datasette.publish.heroku", "datasette.publish.now")
DEFAULT_PLUGINS = (
"datasette.publish.heroku",
"datasette.publish.now",
"datasette.facets",
)
pm = pluggy.PluginManager("datasette")
pm.add_hookspecs(hookspecs)