Search public functions

-- load into db as superuser
CREATE OR REPLACE FUNCTION search_public_functions(p_search_strings TEXT, p_case_insensitive BOOLEAN, OUT function_name TEXT, OUT matching_terms TEXT) RETURNS SETOF RECORD AS
$body$
DECLARE
        x                       RECORD;
        qry                     TEXT;
        v_match                 BOOLEAN := 'false';
        v_matches               TEXT;
        v_search_strings        TEXT := p_search_strings;
        v_case_insensitive      BOOLEAN := p_case_insensitive;
        v_funcdef               TEXT;
BEGIN
        /* v_search_strings is a list, pipe-separated, exactly what we want to search against.
           NOTE: works on postgresql v8.4
           example:
           select function_name,matching_terms from search_public_functions('crosstab|intersect|except|ctid',true);
        */
 
        IF (v_case_insensitive IS NOT FALSE) THEN
                v_case_insensitive := TRUE;
        END IF;
 
        qry :=  'SELECT n.nspname||''.''||p.proname||'' (''||pg_catalog.pg_get_function_arguments(p.oid)||'')''::TEXT as funcname,
                        (select pg_catalog.pg_get_functiondef(p.oid)) as funcdef,
                        p.oid as funcoid
                FROM pg_catalog.pg_proc p
                     LEFT JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace
                WHERE pg_catalog.pg_function_is_visible(p.oid)
                AND n.nspname <> ''pg_catalog''
                AND n.nspname <> ''information_schema''
                AND NOT p.proisagg
                ORDER BY 1';
 
        IF (p_case_insensitive IS TRUE) THEN
                v_search_strings := LOWER(v_search_strings);
        END IF;
 
        FOR x IN EXECUTE qry LOOP
                v_match := 'false';
                function_name := NULL;
                v_funcdef := NULL;
 
                SELECT INTO v_match x.funcdef ~* v_search_strings;
 
                IF ( v_match IS TRUE ) THEN
                        v_matches := NULL;
                        v_funcdef := x.funcdef;
                        IF (p_case_insensitive IS TRUE) THEN
                                v_funcdef := LOWER(v_funcdef);
                        END IF;
                        SELECT array_to_string(array_agg(val),',') INTO v_matches FROM (SELECT DISTINCT array_to_string(regexp_matches(v_funcdef, v_search_strings ,'g'),',') AS val) AS y2;
 
                        function_name := x.funcname;
                        matching_terms := v_matches;
                        RETURN NEXT;
                END IF;
        END LOOP;
END;
$body$ language plpgsql SECURITY DEFINER;