index.js

const knexConstructor = require('knex');

function connect(settings) {
  const knex = knexConstructor(settings);
  const defaultOptions = {
    dateField: 'created_at',
    dbApi: knex,
    limit: 1000,
    offset: 0,
    sortOrder: 'ASC',
  };

  return {
    browse(table, fields, filter, options = {}) {
      const dbApi = options.dbApi || defaultOptions.dbApi || knex;
      const limit = options.limit || defaultOptions.limit;
      const offset = options.offset || defaultOptions.offset;
      const dateField = options.dateField || defaultOptions.dateField;
      const sortOrder = options.sortOrder || defaultOptions.sortOrder;

      let query = dbApi(table)
        .where(filter)
        .select(fields)
        .limit(limit)
        .offset(offset);

      if (options.search_start_date && options.search_end_date) {
        query = query
          .whereBetween(dateField, [options.search_start_date, options.search_end_date]);
      }

      if (options.orderBy) {
        if(Array.isArray(options.orderBy)) {
          options.orderBy.forEach((orderBy, index) => {
            if(Array.isArray(sortOrder)) {
              return query = query.orderBy(orderBy, sortOrder[index]);
            }
            query = query.orderBy(orderBy, sortOrder);
          });
        } else {
          query = query.orderBy(options.orderBy, sortOrder);
        }
      }

      return query;
    },
    read(table, fields, filter, options = {}) {
      const dbApi = options.dbApi || knex;
      return dbApi(table)
        .where(filter)
        .select(fields)
        .then(([row]) => {
          return row;
        });
    },
    add(table, fields, data, options = {}) {
      const dbApi = options.dbApi || knex;
      return dbApi(table)
        .returning(fields)
        .insert(data)
        .then(([row]) => {
          return row;
        });
    },
    edit(table, fields, data, filter, options = {}) {
      const dbApi = options.dbApi || knex;
      return dbApi(table)
        .where(filter)
        .returning(fields)
        .update(data)
        .then(([row]) => {
          return row;
        });
    },
    del(table, filter, options = {}) {
      const dbApi = options.dbApi || knex;
      return dbApi(table)
        .where(filter)
        .del();
    },
    raw(sql, options = {}) {
      const dbApi = options.dbApi || knex;
      return dbApi.raw(sql, options)
        .then(res => res.rows || res);
    }
  };
}

module.exports = connect;