A function to be used with Ember Mirage to handle requests with query params

config.js

export default function() {
  this.get('foo', queryParamHandler('foo'));
}

mirage-query-param-handler.js

const queryParamHandler = (model) => {
  return function(db, req) {
    const query = _.omit(req.queryParams, 'sortBy', 'sortDir', 'offset', 'limit');
    const sortBy = req.queryParams.sortBy || 'id';
    const sortDir = req.queryParams.sortBy || 'asc';
    const offset = parseInt(req.queryParams.offset || 0);
    const limit = parseInt(req.queryParams.limit || 20);

    const filter = (item) => {
      for (const k in query) {
        const val = query[k];

        if (!_.includes(k, 'filter')) {
          if (_.isArray(val)) {
            if (!_.contains(val, item[k])) {
              return false;
            }
          } else if (val !== item[k]) {
            return false;
          }
        }
      }

      return true;
    };

    const multiple = sortDir === 'asc' ? 1 : -1;
    const sort = (a, b) => {
      const aVal = a[sortBy];
      const bVal = b[sortBy];

      if (aVal === bVal) {
        return 0;
      }

      if (aVal < bVal) {
        return multiple * -1;
      }

      return multiple * 1;
    };

    const items = db[model].all().filter(filter).sort(sort);

    const resp = this.serialize(items.slice(offset, offset + limit));
    resp.meta = { pagination: { total: items.length, offset, limit } };

    return resp;
  };
};