OpenZeppelin Nile ⛵

Navigate your StarkNet projects written in Cairo.

Getting started

Create a folder for your project and cd into it:

mkdir myproject
cd myproject

Create a virtualenv and activate it:

python3 -m venv env
source env/bin/activate

Install nile:

pip install cairo-nile

Use nile to quickly set up your development environment:

nile init
...
✨  Cairo successfully installed!
...
✅ Dependencies successfully installed
🗄  Creating project directory tree
⛵️ Nile project ready! Try running:

This command creates the project directory structure and installs cairo-lang, starknet-devnet, pytest, and pytest-asyncio for you. The template includes a makefile to build the project (make build) and run tests (make test).

Usage

node

Run a local starknet-devnet node:

nile node

 * Serving Flask app 'starknet_devnet.server' (lazy loading)
 * Environment: production
   WARNING: This is a development server. Do not use it in a production deployment.
   Use a production WSGI server instead.
 * Debug mode: off
 * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)

compile

Compile Cairo contracts. Compilation artifacts are written into the artifacts/ directory.

nile compile # compiles all contracts under contracts/
nile compile --directory my_contracts # compiles all contracts under my_contracts/
nile compile contracts/MyContract.cairo # compiles single contract
nile compile contracts/MyContract.cairo --disable-hint-validation # compiles single contract with unwhitelisted hints

As of cairo-lang v0.8.0, account contracts (contracts with the __execute__ method) must be compiled with the --account_contract flag. Nile automatically inserts the flag if the contract's name ends with Account i.e. Account.cairo, EthAccount.cairo. Otherwise, the flag must be included by the user.

nile compile contracts/NewAccountType.cairo --account_contract # compiles account contract

Example output:

$ nile compile
Creating artifacts/abis/ to store compilation artifacts
🤖 Compiling all Cairo contracts in the contracts/ directory
🔨 Compiling contracts/Account.cairo
🔨 Compiling contracts/Initializable.cairo
🔨 Compiling contracts/Ownable.cairo
✅ Done

deploy

nile deploy contract --alias my_contract

🚀 Deploying contract
🌕 artifacts/contract.json successfully deployed to 0x07ec10eb0758f7b1bc5aed0d5b4d30db0ab3c087eba85d60858be46c1a5e4680
📦 Registering deployment as my_contract in localhost.deployments.txt

A few things to notice here:

1. nile deploy <contract_name> looks for an artifact with the same name
2. This created a localhost.deployments.txt file storing all data related to my deployment
3. The --alias parameter lets me create an unique identifier for future interactions, if no alias is set then the contract's address can be used as identifier
4. By default Nile works on local, but you can use the --network parameter to interact with mainnet, goerli, and the default localhost.

setup

Deploy an Account associated with a given private key.

To avoid accidentally leaking private keys, this command takes an alias instead of the actual private key. This alias is associated with an environmental variable of the same name, whose value is the actual private key.

You can find an example .env file in example.env. These are private keys only to be used for testing and never in production.

nile setup <private_key_alias>

🚀 Deploying Account
🌕 artifacts/Account.json successfully deployed to 0x07db6b52c8ab888183277bc6411c400136fe566c0eebfb96fffa559b2e60e794
📦 Registering deployment as account-0 in localhost.deployments.txt
Invoke transaction was sent.
Contract address: 0x07db6b52c8ab888183277bc6411c400136fe566c0eebfb96fffa559b2e60e794
Transaction hash: 0x17

A few things to notice here:

1. nile setup <private_key_alias> looks for an environment variable with the name of the private key alias
2. This creates a localhost.accounts.json file storing all data related to accounts management

send

Execute a transaction through the Account associated with the private key provided. The syntax is:

nile send <private_key_alias> <contract_identifier> <method> [PARAM_1, PARAM2...]

For example:

nile send <private_key_alias> ownable0 transfer_ownership 0x07db6...60e794

Invoke transaction was sent.
Contract address: 0x07db6b52c8ab888183277bc6411c400136fe566c0eebfb96fffa559b2e60e794
Transaction hash: 0x1c

call and invoke

Using call and invoke, we can perform read and write operations against our local node (or public one using the --network mainnet parameter). The syntax is:

nile <command> <contract_identifier> <method> [PARAM_1, PARAM2...]

Where <command> is either call or invoke and <contract_identifier> is either our contract address or alias, as defined on deploy.

nile invoke my_contract increase_balance 1

Invoke transaction was sent.
Contract address: 0x07ec10eb0758f7b1bc5aed0d5b4d30db0ab3c087eba85d60858be46c1a5e4680
Transaction hash: 0x1

nile call my_contract get_balance

1

run

Execute a script in the context of Nile. The script must implement a run(nre) function to receive a NileRuntimeEnvironment object exposing Nile's scripting API.

# path/to/script.py

def run(nre):
    address, abi = nre.deploy("contract", alias="my_contract")
    print(abi, address)

Then run the script:

nile run path/to/script.py

clean

Deletes the artifacts/ directory for a fresh start ❄️

nile clean

🚮 Deleting localhost.deployments.txt
🚮 Deleting artifacts directory
✨ Workspace clean, keep going!

install

Install the latest version of the Cairo language and the starknet-devnet local node.

nile install

version

Print out the Nile version

nile version

debug

Use locally available contracts to make error messages from rejected transactions more explicit.

nile debug <transaction_hash> [CONTRACTS_FILE, NETWORK]

For example, this transaction returns the very cryptic error message:
An ASSERT_EQ instruction failed: 0 != 1.

starknet tx_status \
  --hash 0x57d2d844923f9fe5ef54ed7084df61f926b9a2a24eb5d7e46c8f6dbcd4baafe \
  --error_message

[...]
Error in the called contract (0x5bf05eece944b360ff0098eb9288e49bd0007e5a9ed80aefcb740e680e67ea4):
Error at pc=0:1360:
An ASSERT_EQ instruction failed: 0 != 1.
Cairo traceback (most recent call last):
Unknown location (pc=0:1384)
Unknown location (pc=0:1369)

This can be made more explicit with:

nile debug 0x57d2d844923f9fe5ef54ed7084df61f926b9a2a24eb5d7e46c8f6dbcd4baafe

⏳ Querying the network to check transaction status and identify contracts...
🧾 Found contracts: ['0x05bf05eece944b360ff0098eb9288e49bd0007e5a9ed80aefcb740e680e67ea4:artifacts/Evaluator.json']
⏳ Querying the network with contracts...
🧾 Error message:

[...]
Error in the called contract (0x5bf05eece944b360ff0098eb9288e49bd0007e5a9ed80aefcb740e680e67ea4):
[path_to_file]:179:5: Error at pc=0:1360:
    assert permission = 1
    ^*******************^
An ASSERT_EQ instruction failed: 0 != 1.
Cairo traceback (most recent call last):
[path_to_file]:184:6
func set_teacher{
     ^*********^
[path_to_file]:189:5
    only_teacher()
    ^************^

In case of pending transaction states, the command will offer to continue probing the network unless it is terminated prematurely. This example also shows how accepted transactions are handled.

⏳ Querying the network to check transaction status and identify contracts...
🕒 Transaction status: NOT_RECEIVED. Trying again in a moment...
🕒 Transaction status: RECEIVED. Trying again in a moment...
🕒 Transaction status: PENDING. Trying again in a moment...
✅ Transaction status: ACCEPTED_ON_L2. No error in transaction.

Finally, the command will use the local network.deployments.txt files to fetch the available contracts.
However, it is also possible to override this by passing a CONTRACTS_FILE argument, formatted as:

CONTRACT_ADDRESS1:PATH_TO_COMPILED_CONTRACT1.json
CONTRACT_ADDRESS2:PATH_TO_COMPILED_CONTRACT2.json
...

Extending Nile with plugins

Nile has the possibility of extending its CLI and NileRuntimeEnvironment functionalities through plugins. For developing plugins for Nile fork this plugin example boilerplate and implement your desired functionality with the provided instructions.

How it works

This implementation takes advantage of the native extensibility features of click. Using click and leveraging the Python entrypoints we have a simple manner of handling extension natively on Python environments through dependencies. The plugin implementation on Nile looks for specific Python entrypoints constraints for adding commands.

In order for this implementation to be functional, it is needed by the plugin developer to follow some development guidelines defined in this simple plugin example extending Nile for a dummy greet extension. In a brief explanation the guidelines are as follows:

1. Define a Python module that implement a click command or group:

   # First, import click dependency
   import click
   
   # Decorate the method that will be the command name with `click.command` 
   @click.command()
   # You can define custom parameters as defined in `click`: https://click.palletsprojects.com/en/7.x/options/
   def my_command():
       # Help message to show with the command
       """
       Subcommand plugin that does something.
       """
       # Done! Now implement your custom functionality in the command
       click.echo("I'm a plugin overiding a command!")

2. Define the plugin entrypoint. In this case using Poetry features in the pyproject.toml file:

   # We need to specify that click commands are Poetry entrypoints of type `nile_plugins`. Do not modify this
   [tool.poetry.plugins."nile_plugins"]
   # Here you specify you command name and location <command_name> = <package_method_location>
   "greet" = "nile_greet.main.greet"

3. Done!

How to decide if I want to use a plugin or not? Just install / uninstall the plugin dependency from your project 😄

Finally, after the desired plugin is installed, it will also be automatically available through the nre. The plugin developer should be aware of this and design the interface accordingly.

Hacking on Nile

Nile uses tox to manage development tasks, you can get a list of available task with tox -av.

• Install a development version of the package with python -m pip install .
• Build the package with tox -e build
• Format all files with tox -e format
• Check files formatting with tox -e lint

Testing

To run tests:

• Install testing dependencies with python -m pip install .[testing]
• Run all tests with tox
• Run unit tests only with tox -e unit
• To run a specific set of tests, point to a module and/or function, e.g. toxtests/test_module.py::test_function
• Other pytest flags must be preceded by --, e.g. tox -- --pdb to runtests in debug mode

License

Nile is released under the MIT License.