typer command

The typer command provides ✨ completion ✨ in the Terminal for your own small scripts. Even if they don't use Typer internally. Of course, it works better if you use Typer in your script.

It's probably most useful if you have a small custom Python script using Typer (maybe as part of some project), for some small tasks, and it's not complex/important enough to create a whole installable Python package for it (something to be installed with pip).

In that case, you can run your program with the typer command in your Terminal, and it will provide completion for your script.

The typer command also has functionality to generate Markdown documentation for your own Typer programs 📝.

Install

When you install Typer with:

pip install typer

...it includes the typer command.

If you don't want to have the typer command, you can install instead:

pip install typer-slim

You can still use it by calling the Typer library as a module with:

python -m typer

Install completion

You can then install completion for the typer command with:

fast →typer --install-completion
bash completion installed in /home/user/.bashrc.
Completion will take effect once you restart the terminal.

restart ↻

Sample script

Let's say you have a script that uses Typer in my_custom_script.py:

from typing import Optional

import typer

app = typer.Typer()


@app.command()
def hello(name: Optional[str] = None):
    if name:
        typer.echo(f"Hello {name}")
    else:
        typer.echo("Hello World!")


@app.command()
def bye(name: Optional[str] = None):
    if name:
        typer.echo(f"Bye {name}")
    else:
        typer.echo("Goodbye!")


if __name__ == "__main__":
    app()

For it to work, you would also install Typer:

fast →python -m pip install typerSuccessfully installed typer

restart ↻

Run with Python

Then you could run your script with normal Python:

fast →python my_custom_script.py hello
Hello World!

python my_custom_script.py hello --name Camila
Hello Camila!

python my_custom_script.py bye --name Camila
Bye Camila

restart ↻

There's nothing wrong with using Python directly to run it. And, in fact, if some other code or program uses your script, that would probably be the best way to do it.

⛔️ But in your terminal, you won't get completion when hitting TAB for any of the subcommands or options, like hello, bye, and --name.

Run with the typer command.

You can also run the same script with the typer command:

fast →typer my_custom_script.py run hello
Hello World!

typer my_custom_script.py run hello --name Camila
Hello Camila!

typer my_custom_script.py run bye --name Camila
Bye Camila

restart ↻

• Instead of using python directly you use the typer command.
• After the name of the file, add the subcommand run.

✔️ If you installed completion for the typer command as described above, when you hit TAB you will have ✨ completion for everything ✨, including all the subcommands and options of your script, like hello, bye, and --name 🚀.

If main

Because the typer command won't use the block with:

if __name__ == "__main__":
    app()

...you can also remove it if you are calling that script only with the typer command.

Run other files

The typer command can run any script with Typer, but the script doesn't even have to use Typer at all.

You could even run a file with a function that could be used with typer.run(), even if the script doesn't use typer.run() or anything else.

For example, a file main.py like this will still work:

def main(name: str = "World"):
    """
    Say hi to someone, by default to the World.
    """
    print(f"Hello {name}")

Then you can call it with:

fast →typer main.py run --helpUsage: typer run [OPTIONS]

  Say hi to someone, by default to the World.

Options:
  --name TEXT
  --help       Show this message and exit.

typer main.py run --name Camila
Hello Camila

restart ↻

And it will also have completion for things like the --name CLI Option.

Run a package or module

Instead of a file path you can pass a module (possibly in a package) to import.

For example:

fast →typer my_package.main run --helpUsage: typer run [OPTIONS]

Options:
  --name TEXT
  --help       Show this message and exit.

typer my_package.main run --name Camila
Hello Camila

restart ↻

Options

You can specify one of the following CLI options:

• --app: the name of the variable with a Typer() object to run as the main app.
• --func: the name of the variable with a function that would be used with typer.run().

Defaults

When your run a script with the typer command it will use the app from the following priority:

• An app object from the --app CLI Option.
• A function to convert to a Typer app from --func CLI Option (like when using typer.run()).
• A Typer app in a variable with a name of app, cli, or main.
• The first Typer app available in the file, with any name.
• A function in a variable with a name of main, cli, or app.
• The first function in the file, with any name.

Generate docs

You can also use the typer command to generate Markdown documentation for your Typer application.

Sample script with docs

For example, you could have a script like:

import typer

app = typer.Typer(help="Awesome CLI user manager.")


@app.command()
def create(username: str):
    """
    Create a new user with USERNAME.
    """
    print(f"Creating user: {username}")


@app.command()
def delete(
    username: str,
    force: bool = typer.Option(
        ...,
        prompt="Are you sure you want to delete the user?",
        help="Force deletion without confirmation.",
    ),
):
    """
    Delete a user with USERNAME.

    If --force is not used, will ask for confirmation.
    """
    if force:
        print(f"Deleting user: {username}")
    else:
        print("Operation cancelled")


@app.command()
def delete_all(
    force: bool = typer.Option(
        ...,
        prompt="Are you sure you want to delete ALL users?",
        help="Force deletion without confirmation.",
    ),
):
    """
    Delete ALL users in the database.

    If --force is not used, will ask for confirmation.
    """
    if force:
        print("Deleting all users")
    else:
        print("Operation cancelled")


@app.command()
def init():
    """
    Initialize the users database.
    """
    print("Initializing user database")


if __name__ == "__main__":
    app()

Generate docs with the typer command

Then you could generate docs for it with the typer command.

You can use the subcommand utils.

And then the subcommand docs.

fast →typer some_script.py utils docs
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Tip

If you installed only typer-slim and you don't have the typer command, you can still generate docs with:

$ python -m typer some_script.py utils docs

Options:

• --name TEXT: The name of the CLI program to use in docs.
• --output FILE: An output file to write docs to, like README.md.
• --title TEXT: A title to use in the docs, by default the name of the command.

For example:

fast →typer my_package.main utils docs --name awesome-cli --output README.md
Docs saved to: README.md

restart ↻

Sample docs output

For example, for the previous script, the generated docs would look like:

---

awesome-cli

Awesome CLI user manager.

Usage:

$ awesome-cli [OPTIONS] COMMAND [ARGS]...

Options:

• --install-completion: Install completion for the current shell.
• --show-completion: Show completion for the current shell, to copy it or customize the installation.
• --help: Show this message and exit.

Commands:

• create: Create a new user with USERNAME.
• delete: Delete a user with USERNAME.
• delete-all: Delete ALL users in the database.
• init: Initialize the users database.

awesome-cli create

Create a new user with USERNAME.

Usage:

$ awesome-cli create [OPTIONS] USERNAME

Options:

• --help: Show this message and exit.

awesome-cli delete

Delete a user with USERNAME.

If --force is not used, will ask for confirmation.

Usage:

$ awesome-cli delete [OPTIONS] USERNAME

Options:

• --force / --no-force: Force deletion without confirmation. [required]
• --help: Show this message and exit.

awesome-cli delete-all

Delete ALL users in the database.

If --force is not used, will ask for confirmation.

Usage:

$ awesome-cli delete-all [OPTIONS]

Options:

• --force / --no-force: Force deletion without confirmation. [required]
• --help: Show this message and exit.

awesome-cli init

Initialize the users database.

Usage:

$ awesome-cli init [OPTIONS]

Options:

• --help: Show this message and exit.