[#3556] populate_full_text_trigger + migration

ckanext/datastore/set_permissions.sql

@@ -49,6 +49,7 @@ GRANT SELECT ON ALL TABLES IN SCHEMA public TO {readuser};
 ALTER DEFAULT PRIVILEGES FOR USER {writeuser} IN SCHEMA public
    GRANT SELECT ON TABLES TO {readuser};
 
+-- a view for listing valid table (resource id) and view names
 CREATE OR REPLACE VIEW "_table_metadata" AS
     SELECT DISTINCT
         substr(md5(dependee.relname || COALESCE(dependent.relname, '')), 0, 17) AS "_id",
@@ -62,11 +63,45 @@ CREATE OR REPLACE VIEW "_table_metadata" AS
         LEFT OUTER JOIN pg_class AS dependent ON d.refobjid = dependent.oid
     WHERE
         (dependee.oid != dependent.oid OR dependent.oid IS NULL) AND
-	-- is a table (from pg_tables view definition)
-	-- or is a view (from pg_views view definition)
+        -- is a table (from pg_tables view definition)
+        -- or is a view (from pg_views view definition)
         (dependee.relkind = 'r'::"char" OR dependee.relkind = 'v'::"char")
-	AND dependee.relnamespace = (
-	    SELECT oid FROM pg_namespace WHERE nspname='public')
+        AND dependee.relnamespace = (
+            SELECT oid FROM pg_namespace WHERE nspname='public')
     ORDER BY dependee.oid DESC;
 ALTER VIEW "_table_metadata" OWNER TO {writeuser};
 GRANT SELECT ON "_table_metadata" TO {readuser};
+
+-- _full_text fields are now updated by a trigger when set to NULL
+CREATE OR REPLACE FUNCTION populate_full_text_trigger() RETURNS trigger
+AS $body$
+    BEGIN
+        IF NEW._full_text IS NOT NULL THEN
+            RETURN NEW;
+        END IF;
+        NEW._full_text := (
+            SELECT to_tsvector(string_agg(value, ' '))
+            FROM json_each_text(row_to_json(NEW.*))
+            WHERE key NOT LIKE '\_%');
+        RETURN NEW;
+    END;
+$body$ LANGUAGE plpgsql;
+
+-- migrate existing tables that don't have full text trigger applied
+DO $body$
+    BEGIN
+        EXECUTE coalesce(
+            (SELECT string_agg(
+                'CREATE TRIGGER zfulltext BEFORE INSERT OR UPDATE ON ' ||
+                quote_ident(relname) || 'FOR EACH ROW EXECUTE PROCEDURE ' ||
+                'populate_full_text_trigger();', ' ')
+            FROM pg_class
+            LEFT OUTER JOIN pg_trigger AS t
+                ON t.tgrelid = relname::regclass AND t.tgname = 'zfulltext'
+            WHERE relkind = 'r'::"char" AND t.tgname IS NULL
+                AND relnamespace = (
+                    SELECT oid FROM pg_namespace WHERE nspname='public')),
+            'SELECT 1;');
+    END;
+$body$;
+