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

Lowest Common Denominator API to supported Databases

import { Readable } from 'node:stream';
import { commonKeyValueDBFullSupport } from '../kv/commonKeyValueDB.js';
export class InMemoryKeyValueDB {
    cfg;
    constructor(cfg = {}) {
        this.cfg = cfg;
    }
    support = {
        ...commonKeyValueDBFullSupport,
    };
    // data[table][id] => any (can be Buffer, or number)
    data = {};
    async ping() { }
    async createTable(_table, _opt) { }
    async deleteByIds(table, ids) {
        this.data[table] ||= {};
        ids.forEach(id => delete this.data[table][id]);
    }
    async getByIds(table, ids) {
        this.data[table] ||= {};
        return ids.map(id => [id, this.data[table][id]]).filter(e => e[1]);
    }
    async saveBatch(table, entries) {
        this.data[table] ||= {};
        entries.forEach(([id, v]) => (this.data[table][id] = v));
    }
    streamIds(table, limit) {
        return Readable.from(Object.keys(this.data[table] || {}).slice(0, limit));
    }
    streamValues(table, limit) {
        return Readable.from(Object.values(this.data[table] || {}).slice(0, limit));
    }
    streamEntries(table, limit) {
        return Readable.from(Object.entries(this.data[table] || {}).slice(0, limit));
    }
    async count(table) {
        this.data[table] ||= {};
        return Object.keys(this.data[table]).length;
    }
    async incrementBatch(table, entries) {
        this.data[table] ||= {};
        return entries.map(([id, by]) => {
            const newValue = Number(this.data[table][id] || 0) + by;
            this.data[table][id] = newValue;
            return [id, newValue];
        });
    }
}