url_trim_query.sqlx

config { hasOutput: true }
/*
 * Copyright 2022 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

CREATE OR REPLACE FUNCTION ${self()}(url STRING, keys_to_trim ARRAY<STRING>) AS ((
SELECT
    url_base || IF(keys IS NULL, '', '?' || keys) || IF(url_hash IS NULL, '', '#' || url_hash)
FROM(
    SELECT
        url_base,
        url_hash,
        STRING_AGG(
            IF(LOWER(SPLIT(url_key, '=')[SAFE_OFFSET(0)]) NOT IN(SELECT LOWER(key) FROM UNNEST(keys_to_trim) AS key),
                url_key,
                NULL),
            '&') AS keys
    FROM(
        SELECT
            SPLIT(url, '?')[SAFE_OFFSET(0)] AS url_base,
            SPLIT(url, '#')[SAFE_OFFSET(1)] AS url_hash,
            IFNULL(SPLIT(SPLIT(SPLIT(url, '?')[SAFE_OFFSET(1)], '#')[SAFE_OFFSET(0)], '&'), [CAST(NULL AS STRING)]) AS url_keys
    ), UNNEST(url_keys) AS url_key
    GROUP BY 1,2)
));