The preview command starts a local preview server for a Redocly project with the @redocly/framework package. A project whose package.json lists a legacy product package, such as @redocly/realm, previews with that package instead. Use the preview server to develop your project locally before deployment.
redocly preview
redocly preview --plan=pro
redocly preview --plan=scale --project-dir=./my-docs-project --port=4001
| Option | Type | Description |
|---|---|---|
| --help | boolean | Show help. |
| --plan | string | Plan whose features the preview enables. Possible values: pro, scale, enterprise. The default value is enterprise. For more details, see plans. |
| --project-dir, -d | string | Path to the project directory. The default value is . (current directory). |
| --port, -p | number | The port to run the preview server on. The default value is 4000. |
By default, previews run in enterprise plan mode, which makes every feature available. Switch the preview to the Pro or Scale plan by setting the --plan option, so you see exactly what that plan includes:
redocly preview --plan=pro
By default, the preview command uses the current directory. To specify another directory, provide a path relative to the current directory using the --project-dir option:
redocly preview --project-dir=./path/to/my/docs/
By default, the preview starts on port 4000, so you can access the docs at http://localhost:4000 or http://127.0.0.1:4000.
To specify a custom port for the preview, pass the desired value using the port option:
redocly preview --port=8888
This command starts the preview on port 8888, so you can access the docs at http://localhost:8888 or http://127.0.0.1:8888.
An Internal Server Error page when running the preview command is often caused by a corrupted or outdated npx cache. The preview command uses npx internally to launch @redocly/framework, and a cached package can sometimes cause issues.
Clear the npx cache:
npm cache clean --force
After clearing the cache, try running the preview command again.
Install Redocly CLI globally to avoid cache-related issues:
npm install -g @redocly/cli@latest
After installation, the redocly command is available globally, which helps avoid npx cache issues.