Windshaft-cartodb/lib/cartodb/utils/date-wrapper.js

const DATE_OIDS = Object.freeze({
    1082: 'DATE',
    1083: 'TIME',
    1114: 'TIMESTAMP',
    1184: 'TIMESTAMPTZ',
    1266: 'TIMETZ'
});

/**
 * Wrap a query transforming all date columns into a unix epoch
 * @param {*} originalQuery
 * @param {*} fields
 */
function wrapDates(originalQuery, fields) {
    return `
        SELECT
            ${fields.map(field =>  _isDateType(field) ? _castColumnToEpoch(field.name) : `${field.name}`).join(',')}
        FROM
            (${originalQuery}) _cdb_epoch_transformation `;
}

/**
 * @param {object} field
 */
function _isDateType(field) {
    return DATE_OIDS.hasOwnProperty(field.dataTypeID);
}

/**
 * Return a sql query to transform a date column into a unix epoch
 * @param {string} column - The name of the date column
 */
function _castColumnToEpoch(columnName) {
    return `date_part('epoch', "${columnName}") as "${columnName}"`;
}

function getColumnsWithWrappedDates(query) {
    if (query) {
        if (query.match(/\b_cdb_epoch_transformation\b/)) {
            const columns = [];
            const fieldMatcher = /\bdate_part\('epoch', "([^"]+)"\) as "([^"]+)"/gmi;
            let match;
            do {
                match = fieldMatcher.exec(query);
                if (match && match[1] === match[2]) {
                    columns.push(match[1]);
                }
            } while (match);
            return columns;
        }
    }
}

module.exports = {
    wrapDates,
    getColumnsWithWrappedDates
};