Scripting

You can write scripts that run using the ape run command. The ape run command will register and run Python files defined under the scripts/ directory that do not start with an _ underscore.

CLI Scripts

Place scripts in your project’s scripts/ directory. Follow this guide to learn more about the Ape project structure. If your scripts take advantage of utilities from our ape.cli submodule, you can build a Click command line interface by defining a click.Command or click.Group object called cli in your file: Follow this guide to learn more about what you can do with the utilities found in ape.cli.

import click

@click.command()
def cli():
    print("Hello world!")

Assume we named the script helloworld.py. To execute the script, run the following:

ape run helloworld

You can also execute scripts in subdirectories. For example, assuming we have script <project>/scripts/hello/helloworld.py, we would execute it by running:

ape run hello helloworld

Note: By default, cli scripts do not have ape.cli.network_option installed, giving you more flexibility in how you define your scripts. However, you can add the network_option or ConnectedProviderCommand to your scripts by importing them from the ape.cli namespace:

import click
from ape.cli import ConnectedProviderCommand


@click.command(cls=ConnectedProviderCommand)
def cli(ecosystem, network):
    click.echo(f"You selected a provider on ecosystem '{ecosystem.name}' and {network.name}.")

@click.command(cls=ConnectedProviderCommand)
def cli(network, provider):
    click.echo(f"You are connected to network '{network.name}'.")
    click.echo(provider.chain_id)

@click.command(cls=ConnectedProviderCommand)
def cli_2():
    click.echo(f"Using any network-based argument is completely optional.")

Assume we saved this script as shownet.py and have the ape-alchemy plugin installed. Try changing the network using the --network option:

ape run shownet --network ethereum:mainnet:alchemy

Multi-network Scripting

Because CLI-based scripts do not automatically connect to the provider before executing, they are ideal for multi-chain use-cases because they allow you to delay and manage the connection(s). To learn more about how to control the network-context in Ape Pythonically, see this guide.

Here is an example of a multi-chain script:

import click
from ape.cli import ape_cli_context

@click.command()
@ape_cli_context()
def cli(cli_ctx):        
    # There is no connection yet at this point.
    testnets = {
        "ethereum": ["sepolia", "goerli"],
        "polygon": ["mumbai"]
    }
    nm = cli_ctx.network_manager

    for ecosystem_name, networks in testnets.items():
        ecosystem = nm.ecosystems[ecosystem_name]

        for network_name in networks:
            # Start making connections.
            network = ecosystem.get_network(network_name)

            with network.use_provider("alchemy") as provider:
                print(f"Connected to {provider.network_choice}")

Things to notice:

1. It uses the CLI approach without cls=ConnectedProviderCommand; thus it is not connected before it makes the first call to .use_provider("alchemy").

2. It uses the @ape_cli_context() decorator to get access to Ape instances such as the network_manager.

3. Each network is only active during the context, thus allowing you to switch contexts and control chain-hopping in scripts.

4. You do not need to call .connect() on the provider yourself!

Main Method Scripts

You can also use the main-method approach when defining scripts. To do this, define a method named main() in your script:

def main():
    print("Hello world!")

NOTE: main-method scripts will always provide a --network option and run in a connected-context. Therefore, they are not ideal for multi-chain scripts. main-method scripts work best for quick, single-network, connection-based workflows.

To demonstrate, use the following script:

from ape import networks
import click

def main():
    ecosystem_name = networks.provider.network.ecosystem.name
    network_name = networks.provider.network.name
    provider_name = networks.provider.name
    click.echo(f"You are connected to network '{ecosystem_name}:{network_name}:{provider_name}'.")

Suppose the name of the script is foobar, you can run it via:

ape run foobar

Without specifying --network, the script with connect to your default network. Else, specify the network using the --network flag:

ape run foobar --network polygon:mumbai:alchemy

You can also change networks within the script using the ProviderContextManager (see examples in the CLI-script section above). For multi-chain use-cases, we recommend sticking to the CLI based scripts to avoid the initial connection main-method scripts make.