traxxx/src/utils/upsert.js

'use strict';

async function upsert(table, items, identifier = 'id', knex) {
    const duplicates = await knex(table).whereIn(identifier, items.map(item => item[identifier]));
    const duplicatesByIdentifier = duplicates.reduce((acc, item) => ({ ...acc, [item[identifier]]: item }), {});

    const { insert, update } = items.reduce((acc, item) => {
        if (duplicatesByIdentifier[item[identifier]]) {
            acc.update.push(item);
            return acc;
        }

        acc.insert.push(item);
        return acc;
    }, {
        insert: [],
        update: [],
    });

    if (knex) {
        console.log(`${table}: Inserting ${insert.length}`);
        console.log(`${table}: Updating ${update.length}`);

        const [inserted, updated] = await Promise.all([
            knex(table).returning('*').insert(insert),
            knex.transaction(async trx => Promise.all(update.map(item => trx
                .where({ [identifier]: item[identifier] })
                .update(item)
                .into(table)
                .returning('*')))),
        ]);

        return {
            inserted: Array.isArray(inserted) ? inserted : [],
            updated: updated.reduce((acc, updatedItems) => acc.concat(updatedItems), []),
        };
    }

    return { insert, update };
}

module.exports = upsert;