tsgonest migrate

tsgonest migrate is an AST-based codemod that rewrites your NestJS project to use tsgonest in a single command. It handles decorator replacement, class-to-interface conversion, branded type insertion, import cleanup, and dependency management.

Usage

# Preview changes (dry-run, no files modified)
npx tsgonest migrate

# Apply changes (interactive)
npx tsgonest migrate --apply

# Apply changes (non-interactive, accept all defaults)
npx tsgonest migrate --apply --yes

Flags

Flag	Description	Default
`--apply`	Write changes to disk	`false` (dry-run preview)
`--include <glob>`	Glob pattern for files to migrate (repeatable)	`src/*/.ts`
`--tsconfig <path>`	Path to tsconfig.json	`tsconfig.json`
`--cwd <path>`	Working directory	current directory
`--force`	Run even if git working directory has uncommitted changes	`false`
`--yes`, `-y`	Accept all prompts (non-interactive mode)	`false`

Supported Sources

Source	What gets migrated
class-validator	Class DTOs to interfaces with branded types (`tags.Email`, `tags.MinLength<N>`, etc.)
class-transformer	`@Type(() => Number)` to `tags.Coerce`, `@Transform` trim/case to `tags.Trim`/`tags.ToLowerCase`
@nestjs/swagger	Removes redundant decorators (`@ApiProperty`, `@ApiTags`, etc.), auto-detects security schemes
Nestia	`@TypedRoute.Get()` to `@Get()`, `@TypedBody()` to `@Body()`, `@TypedFormData.Body()` to `@FormDataBody()`
Typia	`import { tags } from 'typia'` to `import { tags } from '@tsgonest/types'`, removes `typia.assert<T>()` calls

What Happens

Git check — Requires a clean working directory (use --force to skip)
Detection — Scans imports to determine which migration sources are present
Migration plan — In interactive mode, asks for confirmation on each step
baseUrl import rewriting — If tsconfig.json has baseUrl, bare imports are rewritten to relative paths before baseUrl is removed
Source transforms — Runs AST codemods for each detected source
Import cleanup — Removes empty/unused imports left by transforms
Dependency management — Removes old packages, adds tsgonest packages
Script updates — Updates build and dev scripts in package.json
Config generation — Creates tsgonest.config.ts with auto-detected settings
tsconfig cleanup — Removes baseUrl and compiler plugins

Migration Report

After --apply, a tsgonest-migrate-report.md file is written to your project root containing:

Summary — Transform counts by category
Auto-generated changes — Config files created, tsconfig modifications
Package changes — Dependencies added/removed, scripts updated
Manual TODOs — Items needing human review (custom validators, @Exclude, SwaggerModule, etc.)
Warnings — Non-critical issues (packages still imported, parse errors)

Examples

# Migrate only DTO files
npx tsgonest migrate --apply --include "src/**/*.dto.ts"

# Migrate with a custom tsconfig
npx tsgonest migrate --apply --tsconfig tsconfig.build.json

# CI-friendly: non-interactive, force run
npx tsgonest migrate --apply --yes --force

Detailed Guides

For source-specific migration details: