typescript-migration

import { Migration } from 'typescript-migration'; import { SourceFile } from 'ts-morph'; import * as path from 'path'; import * as fs from 'fs'; // 1. Define your migration in a file, e.g., 'src/migrations/001-rename-user-interface.ts' // This migration renames an interface from 'IUser' to 'User'. class RenameUserInterface extends Migration { name = 'Rename IUser to User Interface'; async up(sourceFile: SourceFile): Promise<void> { const oldInterface = sourceFile.getInterface('IUser'); if (oldInterface) { oldInterface.rename('User'); this.log(`Renamed IUser to User in ${sourceFile.getFilePath()}`); } } async down(sourceFile: SourceFile): Promise<void> { const newInterface = sourceFile.getInterface('User'); if (newInterface) { newInterface.rename('IUser'); this.log(`Renamed User back to IUser in ${sourceFile.getFilePath()}`); } } } // For demonstration, create a dummy TypeScript file to migrate. const dummyFilePath = path.join(process.cwd(), 'temp-source.ts'); const dummyContent = `interface IUser { id: string; name: string; }\nconst user: IUser = { id: '1', name: 'Alice' };`; // For CLI usage, you would place this migration file in a designated migrations directory. // For programmatic usage (shown here for simplicity): async function runMigrationProgrammatically() { // Ensure temp-source.ts exists for the demo fs.writeFileSync(dummyFilePath, dummyContent); console.log('Created temp-source.ts'); // To run this via the CLI, you would save RenameUserInterface to a file // and execute: npx typescript-migration run --up path/to/migrations_folder // Programmatic execution example: const { Migrator } = await import('typescript-migration'); const migrator = new Migrator(); // Instantiate your migration const migrationInstance = new RenameUserInterface(); // Apply the 'up' migration to the dummy file console.log('\n--- Running UP migration ---'); await migrator.run([migrationInstance], [dummyFilePath], 'up'); console.log('Migration UP finished.'); // Verify changes (read the file content after migration) const updatedContent = fs.readFileSync(dummyFilePath, 'utf8'); console.log('\nUpdated temp-source.ts content:\n', updatedContent); // Revert the 'down' migration console.log('\n--- Running DOWN migration ---'); await migrator.run([migrationInstance], [dummyFilePath], 'down'); console.log('Migration DOWN finished.'); const revertedContent = fs.readFileSync(dummyFilePath, 'utf8'); console.log('\nReverted temp-source.ts content:\n', revertedContent); // Clean up fs.unlinkSync(dummyFilePath); console.log('\nCleaned up temp-source.ts'); } runMigrationProgrammatically().catch(console.error);