Used only recursive queries to map ltree paths to vos paths and added custom...

-- View that maps node_id to os_path (relative path of file on disk)

CREATE VIEW node_os_path AS 

SELECT n.node_id, '/' || STRING_AGG(j.name, '/' ORDER BY t.ord) AS os_path

WITH RECURSIVE r_os_path AS (

    SELECT node_id, relative_path, COALESCE(os_name, name) AS os_path

    FROM node

    WHERE name = ''

  UNION ALL

    SELECT n.node_id, n.relative_path, p.os_path || '/' || COALESCE(os_name, name)

    FROM node n

JOIN REGEXP_SPLIT_TO_TABLE((CASE WHEN relative_path = '' THEN '1' ELSE '1.' || path::text END), '[.]') WITH ORDINALITY t(node_id, ord) ON true

JOIN node j ON j.node_id = t.node_id::int

WHERE j.relative_path IS NOT NULL AND j.relative_path <> ''

GROUP BY n.node_id;

    JOIN r_os_path p ON p.relative_path = n.parent_relative_path

    WHERE n.parent_relative_path IS NOT NULL

)

SELECT node_id, (CASE WHEN os_path = '' THEN '/' ELSE os_path END) AS os_path FROM r_os_path;

-- View that maps node_id to vos_path (path in VOSpace)

CREATE VIEW node_vos_path AS

SELECT n.node_id, COALESCE(NULLIF(STRING_AGG(j.name, '/' ORDER BY t.ord), ''), '/') AS vos_path

WITH RECURSIVE r_vos_path AS (

    SELECT node_id, path, name AS vos_path

    FROM node

    WHERE name = ''

  UNION ALL

    SELECT n.node_id, n.path, p.vos_path || '/' || name

    FROM node n

JOIN REGEXP_SPLIT_TO_TABLE((CASE WHEN path = '' THEN '1' ELSE '1.' || path::text END), '[.]') WITH ORDINALITY t(node_id, ord) ON true

JOIN node j ON j.node_id = t.node_id::int

GROUP BY n.node_id;

    JOIN r_vos_path p ON p.path = n.parent_path

)

SELECT node_id, (CASE WHEN path = '' THEN '/' ELSE vos_path END) AS vos_path FROM r_vos_path;

-- View that combines the two previous views to obtain the os_path from the vos_path and vice versa

)

SELECT node_id FROM r_vos_path WHERE vos_path = vos_path_input

$func$ LANGUAGE sql;

-- Returns vos_path from node_id

CREATE OR REPLACE FUNCTION get_vos_path(input_id BIGINT) RETURNS VARCHAR AS

$func$

SELECT string_agg(name, '/') FROM (

    WITH RECURSIVE paths AS (

            SELECT node_id, name, path, parent_path, 1 AS level

            FROM node

            WHERE node_id = input_id

        UNION ALL

            SELECT f.node_id, f.name, f.path, f.parent_path, p.level + 1

            FROM node f

            INNER JOIN paths p ON p.parent_path = f.path

    ) SELECT name FROM paths ORDER BY LEVEL DESC

) AS names

$func$ LANGUAGE sql;

-- Returns os_path from node_id

CREATE OR REPLACE FUNCTION get_os_path(input_id BIGINT) RETURNS VARCHAR AS

$func$

SELECT '/' || string_agg(name, '/') FROM (

    WITH RECURSIVE paths AS (

            SELECT node_id, COALESCE(os_name, name) AS name, relative_path, parent_relative_path, 1 AS level

            FROM node

            WHERE node_id = input_id

        UNION ALL

            SELECT f.node_id, COALESCE(f.os_name, f.name) AS name, f.relative_path, f.parent_relative_path, p.level + 1

            FROM node f

            INNER JOIN paths p ON p.parent_relative_path = f.relative_path

            WHERE f.parent_relative_path IS NOT NULL

    ) SELECT name FROM paths ORDER BY LEVEL DESC

) AS names

$func$ LANGUAGE sql;