Fix enum statements in TypeORM migration

fix-enum.mjs

#!/usr/bin/env node

// This fix TypeORM enum creation, which generate multiple CREATE TYPE statement
// when an enum is used in multiple columns.
// The solution is taken from this SO answer: https://stackoverflow.com/a/48382296
// which gracefully handle the exception
// - https://github.com/typeorm/typeorm/issues/5648
// - https://github.com/typeorm/typeorm/issues/5738
// - https://github.com/typeorm/typeorm/issues/7501

import { existsSync, readFileSync, writeFileSync } from 'node:fs';
import { resolve } from 'node:path';
import { argv, cwd, exit } from 'node:process';

/**
 * Extract arguments from `argv`, validate filePath exists
 *
 * @returns {object} Contains `filePath`
 */
function extractArguments() {
  // Validate argv
  if (argv.length !== 3) {
    console.log('Usage: yarn run db:migration:fix-enum <RELATIVE_FILE_PATH>');
    exit(1);
  }

  // Extract arguments
  const [, , filePath] = argv;

  // Validate filePath exists
  const absoluteFilePath = resolve(cwd(), filePath);
  if (!existsSync(absoluteFilePath)) {
    console.log(`file at ${absoluteFilePath} doesn't exists`);
    exit(1);
  }

  console.log('arguments:');
  console.log(`- filePath=${filePath}`);

  return { absoluteFilePath };
}

/**
 * Wrap all CREATE TYPE statement in `content` with DO/EXCEPTION
 * to ignore exception when the type already exists
 *
 * @see https://stackoverflow.com/a/48382296
 * @param {String} content
 * @returns {String}
 */
function fixEnumCreateStatement(content) {
  const regex =
    /await queryRunner.query\(`\s+(CREATE TYPE ["',a-zA-Z_\s\(\.]+\))\s+`\);/g;

  console.log(`Fix CREATE statement:`);

  const replaceCreateTypeStatement = (match, createStatement) => {
    console.log(`  ${createStatement.trim().replaceAll(/\s+/g, ' ')}`);
    return `await queryRunner.query(\`
      DO $$ BEGIN
        ${createStatement};
      EXCEPTION
        WHEN duplicate_object THEN null;
      END $$;
    \`);`;
  };

  const fixed = content.replaceAll(regex, replaceCreateTypeStatement);

  return fixed;
}

/**
 * Wrap all ALTER TYPE statement in `content` with DO/EXCEPTION
 * to ignore exception when the type name already exists
 *
 * @param {String} content
 * @returns {String}
 */
function fixEnumAlterStatement(content) {
  const regex =
    /await queryRunner.query\(`\s+(ALTER TYPE ["a-zA-Z_\s\.]+)\s+`\);/g;

  console.log(`Fix ALTER statement:`);

  const replaceCreateTypeStatement = (match, alterStatement) => {
    console.log(`  ${alterStatement.trim().replaceAll(/\s+/g, ' ')}`);
    return `await queryRunner.query(\`
      DO $$ BEGIN
        ${alterStatement};
      EXCEPTION
        WHEN duplicate_object THEN null;
      END $$;
    \`);`;
  };

  const fixed = content.replaceAll(regex, replaceCreateTypeStatement);

  return fixed;
}

/**
 * Wrap all DROP TYPE statement in `content` with DO/EXCEPTION
 * to ignore exception when the type is used in other table
 *
 * @param {String} content
 * @returns {String}
 */
function fixEnumDropStatement(content) {
  const regex =
    /await queryRunner.query\(`\s+(DROP TYPE ["a-zA-Z_\s\.]+)\s+`\);/g;

  console.log(`Fix DROP statement:`);

  const replaceCreateTypeStatement = (match, dropStatement) => {
    console.log(`  ${dropStatement.trim()}`);
    return `await queryRunner.query(\`
      DO $$ BEGIN
        ${dropStatement};
      EXCEPTION
        WHEN dependent_objects_still_exist THEN null;
      END $$;
    \`);`;
  };

  const fixed = content.replaceAll(regex, replaceCreateTypeStatement);

  return fixed;
}

// RUN
const { absoluteFilePath } = extractArguments();

let content = readFileSync(absoluteFilePath, { encoding: 'utf-8' });
content = fixEnumCreateStatement(content);
content = fixEnumAlterStatement(content);
content = fixEnumDropStatement(content);
writeFileSync(absoluteFilePath, content);