@ocap/statedb-qldb/lib/table/base.js

OCAP statedb adapter that uses amazon qldb as backend statedb

/* eslint-disable no-underscore-dangle */
const { StateDBTable } = require('@ocap/statedb');
const omit = require('lodash/omit');

const debug = require('debug')(require('../../package.json').name);

class QLDBTable extends StateDBTable {
  constructor(name, driver, uniqIndex) {
    super();

    this.name = name;
    this.driver = driver;
    this.uniqIndex = uniqIndex;
    this.indexes = [];
  }

  // TODO: we should support get record history:
  // - https://docs.aws.amazon.com/qldb/latest/developerguide/working.metadata.html
  // - https://docs.aws.amazon.com/qldb/latest/developerguide/working.history.html

  initialize() {
    return this.driver.executeLambda(async (txn) => {
      await txn.execute(`CREATE TABLE ${this.name}`);
      await txn.execute(`CREATE INDEX ON ${this.name} (${this.uniqIndex})`);
      for (let i = 0; i < this.indexes.length; i++) {
        // eslint-disable-next-line no-await-in-loop
        await txn.execute(`CREATE INDEX ON ${this.name} ("${this.indexes[i]}")`);
      }
      debug('create table and index', { name: this.name, index: this.uniqIndex });
      this.markReady();
    });
  }

  async _create(key, attrs, { txn }) {
    const data = { [this.uniqIndex]: key, ...attrs };
    debug(`insert ${this.name}`, data);
    const result = await txn.execute(`INSERT INTO ${this.name} ?`, data);
    debug(`insert ${this.name}`, key, result.getResultList());

    return data;
  }

  async _get(key, { txn }) {
    if (!key) {
      return null;
    }

    const result = await txn.execute(`SELECT * FROM ${this.name} WHERE ${this.uniqIndex} = ?`, key);
    const item = result.getResultList().shift();
    return item ? JSON.parse(JSON.stringify(item)) : null;
  }

  async _history(key, { txn }) {
    if (!key) {
      return [];
    }

    const metaResult = await txn.execute(
      `SELECT metadata FROM _ql_committed_${this.name} WHERE data.${this.uniqIndex} = ?`,
      key
    );
    const item = metaResult.getResultList().shift();
    if (!item) {
      return [];
    }

    const { metadata } = JSON.parse(JSON.stringify(item));
    // TODO: since qldb does not support pagination, we may hit timeout here before retrieved all data
    const historyResult = await txn.execute(`SELECT * FROM history(${this.name}) WHERE metadata.id = ?`, metadata.id);
    return historyResult.getResultList().map((x) => JSON.parse(JSON.stringify(x)));
  }

  async _update(key, updates, { txn }) {
    // Each time we are doing an override
    const data = { [this.uniqIndex]: key, ...updates };
    debug(`update ${this.name}`, data);
    const result = await txn.execute(`UPDATE ${this.name} AS t SET t = ? WHERE ${this.uniqIndex} = ?`, data, key);
    debug(`update ${this.name}`, key, result.getResultList());

    return data;
  }

  async _reset({ txn }) {
    if (process.env.CI) {
      await txn.execute(`DELETE FROM ${this.name}`);
    }
  }

  updateOrCreate(exist, state, ctx) {
    if (!state[this.uniqIndex]) {
      throw new Error('Cannot update or create without uniq index');
    }

    if (exist) {
      return this.update(state[this.uniqIndex], omit(state, [this.uniqIndex]), ctx);
    }

    return this.create(state[this.uniqIndex], omit(state, [this.uniqIndex]), ctx);
  }
}

module.exports = QLDBTable;