test-easy-psql/dist/migrations.js

Welcome to the test-easy-psql documentation! test-easy-psql is a simple intermediary for querying data in PostgreSQL databases. Whether you're a beginner or an experienced developer, this documentation will help you get started with test-easy-psql and lev

"use strict";

const fs = require("fs");
const path = require("path");
const prompt = require("prompt-sync")({
  sigint: true
});
const DBManager = require("./DBManager");
const {
  Query
} = require("pg");
const {
  v4
} = require("uuid");
class Migrations {
  static migrationsFolder = "migrations";
  static migrationsFolderExists() {
    return fs.existsSync(Migrations.resolvePath(Migrations.migrationsFolder));
  }
  static resolvePath(...entries) {
    return path.join(process.cwd(), ...entries);
  }
  static createMigrationsFolder() {
    if (Migrations.migrationsFolderExists()) {
      return;
    }
    fs.mkdirSync(Migrations.resolvePath(Migrations.migrationsFolder));
  }
  static setMigrationsFolder(name) {
    Migrations.migrationsFolder = name;
  }
  static async runNewMigration(cb) {
    const {
      up,
      down,
      args = []
    } = await cb();
    const filename = `${new Date().getTime()}__migration.json`;
    fs.writeFileSync(Migrations.resolvePath(Migrations.migrationsFolder, filename), JSON.stringify({
      filename,
      up,
      down,
      timestamp: new Date().toUTCString(),
      id: v4(),
      applied: true,
      args
    }));
  }
  static readMigrationFiles() {
    const files = [];
    fs.readdirSync(Migrations.resolvePath(Migrations.migrationsFolder)).forEach(file => {
      files.push(Migrations.resolvePath(Migrations.migrationsFolder, file));
    });
    return files.map(file => JSON.parse(fs.readFileSync(file, {
      encoding: "utf8"
    }).toString()));
  }
  static async applyMigrations() {
    Migrations.createMigrationsFolder();
    const notApplied = Migrations.readMigrationFiles().filter(x => !x.applied);
    for (const migration of notApplied) {
      await DBManager.exec(migration.up, migration.args);
      fs.writeFileSync(Migrations.resolvePath(Migrations.migrationsFolder, migration.filename), JSON.stringify({
        ...migration,
        applied: true
      }));
    }
  }
  static async rollbackToMigration(id) {
    const files = Migrations.readMigrationFiles();
    const migrationIndex = files.findIndex(file => file.id === id);
    if (migrationIndex === -1) {
      console.log(`No such migration: ${id}`);
      return;
    }
    const rollbackItems = files.slice(migrationIndex);
    for (let i = rollbackItems.length - 1; i >= 0; i--) {
      await DBManager.exec(rollbackItems[i].down);
      fs.writeFileSync(Migrations.resolvePath(Migrations.migrationsFolder, rollbackItems[i].filename), JSON.stringify({
        ...rollbackItems[i],
        applied: false
      }));
    }
  }
  static async createMigration({
    up,
    down
  }) {
    await Migrations.runNewMigration(async () => {
      new Query(up);
      new Query(down);
      await DBManager.exec(up);
      return {
        up,
        down
      };
    });
  }
  static async bashMigrationInput() {
    const up = prompt("Enter New SQL Statement: ");
    const down = prompt("Enter The opposite SQL Action: ");
    if (!up || !down) {
      console.log("please provide up and  down properties!");
      process.exit(1);
    }
    await Migrations.runNewMigration(async () => {
      new Query(up);
      new Query(down);
      await DBManager.exec(up);
      return {
        up,
        down
      };
    });
    console.log("completed!!");
    const continueMig = prompt("Press 1 to continue");
    if (continueMig.trim() !== "1") {
      console.log("BYE!");
      process.exit(0);
    }
    await Migrations.bashMigrationInput();
  }
}
module.exports = Migrations;