@naturalcycles/db-lib/dist/inmemory/queryInMemory.js

Lowest Common Denominator API to supported Databases

import { _get, _pick } from '@naturalcycles/js-lib/object/object.util.js';
const FILTER_FNS = {
    '==': (v, val) => v === val,
    '!=': (v, val) => v !== val,
    '<': (v, val) => v < val,
    '<=': (v, val) => v <= val,
    '>': (v, val) => v > val,
    '>=': (v, val) => v >= val,
    in: (v, val) => (val || []).includes(v),
    'not-in': (v, val) => !(val || []).includes(v),
    'array-contains': (v, val) => (v || []).includes(val),
    'array-contains-any': (v, val) => (v && val && v.some(item => val.includes(item))) || false,
};
// Important: q.table is not used in this function, so tablesPrefix is not needed.
// But should be careful here..
export function queryInMemory(q, rows = []) {
    // .filter
    // oxlint-disable-next-line unicorn/no-array-reduce
    rows = q._filters.reduce((rows, filter) => {
        return rows.filter(row => {
            const value = _get(row, filter.name);
            return FILTER_FNS[filter.op](value, filter.val);
        });
    }, rows);
    // .select(fieldNames)
    if (q._selectedFieldNames) {
        rows = rows.map(row => _pick(row, q._selectedFieldNames));
    }
    // todo: only one order is supported (first)
    const [order] = q._orders;
    if (order) {
        const { name, descending } = order;
        rows = rows.sort((a, b) => {
            // oxlint-disable-next-line eqeqeq
            if (a[name] == b[name])
                return 0;
            if (descending) {
                return a[name] < b[name] ? 1 : -1;
            }
            return a[name] > b[name] ? 1 : -1;
        });
    }
    // .offset()
    if (q._offsetValue) {
        rows = rows.slice(q._offsetValue);
    }
    // .limit()
    if (q._limitValue) {
        rows = rows.slice(0, Math.min(q._limitValue, rows.length));
    }
    return rows;
}