@rep-protocol/codemod

Codemod for migrating frontend codebases to the Runtime Environment Protocol.

Transforms framework-specific env var access (import.meta.env.*, process.env.*) to rep.get() calls using AST transforms — preserving formatting and adding the SDK import automatically.

Install

npm install -D @rep-protocol/codemod

Or run without installing:

npx @rep-protocol/codemod --framework vite src/

Usage

rep-codemod [options] [files or directories...]

Options

| Flag | Default | Description | |---|---|---| | -f, --framework <name> | vite | Framework preset: vite, cra, next | | --dry-run | false | Preview changes without writing files | | --extensions <list> | ts,tsx,js,jsx | Comma-separated file extensions to process |

Transforms

--framework vite

Transforms Vite public environment variables:

// Before
const apiUrl = import.meta.env.VITE_API_URL;
const flag = import.meta.env.VITE_FEATURE_FLAGS;

// After
import { rep } from '@rep-protocol/sdk';
const apiUrl = rep.get('API_URL');
const flag = rep.get('FEATURE_FLAGS');

Note: Vite built-ins (import.meta.env.MODE, import.meta.env.DEV, etc.) are left untouched.

--framework cra

Transforms Create React App public environment variables:

// Before
const apiUrl = process.env.REACT_APP_API_URL;

// After
import { rep } from '@rep-protocol/sdk';
const apiUrl = rep.get('API_URL');

--framework next

Transforms Next.js public environment variables:

// Before
const apiUrl = process.env.NEXT_PUBLIC_API_URL;

// After
import { rep } from '@rep-protocol/sdk';
const apiUrl = rep.get('API_URL');

Examples

# Transform all TS/TSX files in src/ (Vite project)
rep-codemod --framework vite src/

# Dry run — see what would change without writing
rep-codemod --framework cra --dry-run src/components/

# Transform specific files
rep-codemod --framework next src/app/page.tsx src/lib/api.ts

# Transform JavaScript files
rep-codemod --framework vite --extensions js,jsx src/

Behaviour

• Idempotent: Running the codemod twice on the same file produces the same result as running it once.
• Import management: Adds import { rep } from '@rep-protocol/sdk' if absent. If the import already exists but lacks the rep specifier, it is added.
• Non-destructive: Only VITE_*, REACT_APP_*, and NEXT_PUBLIC_* prefixed variables are transformed. All other process.env.* and import.meta.env.* access is left unchanged.
• Format-preserving: Uses jscodeshift with recast — original formatting and comments are preserved.

After Migration

1. Remove framework-specific type augmentations (e.g., vite-env.d.ts ImportMeta overrides).
2. Run rep typegen to generate typed overloads for rep.get().
3. Update your container config to set REP_PUBLIC_* environment variables.

Specification

Implements REP-RFC-0001 §10.2 — Migration Path.

License

Apache 2.0