get_path_segment() and is_path_matching() sqlpage functions

[olivierauverlot]

Two new useful functions for building RESTful APIs. They avoid using SQL queries to extract an element from a URL and to check whether a URL matches a pattern. The endpoint code is more readable and more performant. The method is the same regardless of the database.

[lovasoa]

Thanks! Do you have an example of how you would use these functions?

Maybe a regex matching function would be more generally useful, for both matching and extracting components?

[olivierauverlot]

A fake example of how to use these functions. The following code is placed in the /api/v1/users/404.sql file. It allows to manage 3 endpoints.

-- Returns user information (lookup based on UID)
-- GET /api/v1/users/42
SELECT 
    'json' AS component, 
    JSON_OBJECT(
        'name', name,
        'surname', surname
    ) AS contents
FROM users
WHERE   sqlppage.is_path_matching(sqlpage.path(),'/api/v1/users/%') 
   AND  id = sqlpage.get_path_segment(sqlpage.path(),4);

-- Returns all accounts of a user (lookup based on UID)
-- GET /api/v1/users/42/accounts
SELECT
    'json' AS component,
    JSON_OBJECT(
        'uid', sqlpage.get_path_segment(sqlpage.path(),4),
        'logins', (
            SELECT JSON_GROUP_ARRAY(
                JSON_OBJECT(
                    'group', group,
                    'homedir', homedir
                )
            ) FROM accounts
            WHERE accounts.uid = sqlpage.get_path_segment(sqlpage.path(),4)
        )
    ) AS contents
WHERE sqlpage.is_path_matching(sqlpage.path(),'/api/v1/users/%/accounts');

-- Returns detailed account information (lookup based on UID and login)
-- GET /api/v1/users/42/accounts/jdoe
SELECT
    'json' AS component,
    JSON_OBJECT(
        'uid', uid,
        'group', group
        'homedir', homedir
    ) AS contents
FROM
    accounts
WHERE  sqlppage.is_path_matching(sqlpage.path(),'/api/v1/users/%/accounts/%') 
  AND  accounts.uid = sqlpage.get_path_segment(sqlpage.path(),4)
  AND  accounts.login = sqlpage.get_path_segment(sqlpage.path(),6);