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preswald run <file_name>

The preswald run command launches a local development server for your application, enabling you to test and interact with your app in a browser.

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Arguments

• file_name (str):
  The path to the Python script that contains your application code. This is the script the development server will execute.

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Example Usage

To launch the development server for your app:

preswald run hello.py

After running the command, your application will be available locally at:

http://localhost:8501

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Detailed Explanation

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1. Launching the Server

When you run the command, preswald starts a local development server using the specified Python script. This allows you to quickly preview and debug your app in a controlled environment.

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2. Supported Script Format

Any Python file containing valid application logic can be used.

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3. Localhost Access

The app is hosted on localhost, which is a local server accessible only from your machine. Use the provided URL to interact with your app through a browser.

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4. Stopping the Server

To stop the server, press Ctrl+C in the terminal where the command is running.

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5. Error Handling

If the script cannot be executed (e.g., due to missing dependencies or syntax errors), preswald will provide helpful error messages to guide you.

Use the preswald run command to test, iterate, and debug your app effortlessly in a local environment.