Interact with Katana on Starknet. Deploy a Cairo smart contract using Katana

Welcome to this tutorial where we'll guide you through deploying a raw cairo smart using katana as a local devnet. In order to accomplish this, we have to install the following tools.

Install Starkli, Scarb and Katana

To install Starkli, open a new terminal.

curl https://get.starkli.sh | sh
starkliup

You can check your installation by running starkli --version, then you will get the starkli version.

To install Scarb

curl --proto '=https' --tlsv1.2 -sSf https://docs.swmansion.com/scarb/install.sh | sh

You can check your installation by running scarb --version, then you will get the starkli version.

To install Katana, use the dojoup installer from the command line:

curl -L https://install.dojoengine.org | bash
dojoup

You can check your installation by running katana --version, then you will get the katana version.

Basics of Katana and Starkli

katana sequencer

katana --disable-fee

After starting Katana, a list of accounts will be automatically generated and deployed.

Starkli built-in accounts and configuration

Starkli supports a list of built-in accounts for katana. These built-in accounts are for local development and no one should be using them for anything serious anyways. For example the address of the Katana-0 built-in account is 0x6162896d1d7ab204c7ccac6dd5f8e9e7c25ecd5ae4fcb4ad32e57786bb46e03. You can check the full list of account addresses here.

We will need this katana-0 built-in account later when we define our STARKNET_ACCOUNT. For more details about accounts, please refer to the accounts section on the starkli book.

Contract Deployment and Interaction

Create a Simple Storage project

scarb new simple_storage

Add contract dependencies to scarb.toml

[dependencies]
starknet = "2.5.4"
 
[[target.starknet-contract]]

Copy the simple storage contract to lib.cairo

#[starknet::interface]
trait ISimpleStorage<TContractState> {
    fn set(ref self: TContractState, x: u128);
    fn get(self: @TContractState) -> u128;
}
 
#[starknet::contract]
mod SimpleStorage {
    use starknet::get_caller_address;
    use starknet::ContractAddress;
 
    #[storage]
    struct Storage {
        stored_data: u128
    }
 
    #[abi(embed_v0)]
    impl SimpleStorage of super::ISimpleStorage<ContractState> {
        fn set(ref self: ContractState, x: u128) {
            self.stored_data.write(x);
        }
        fn get(self: @ContractState) -> u128 {
            self.stored_data.read()
        }
    }
}

Compile contract and add environment variables

Compile your contract using scarb

scarb build

Having compiled the smart contract, it's time to declare it with Starkli and katana. For clean enviroment management, place the following environment variables in a .env file within the src/ directory.

export STARKNET_ACCOUNT=katana-0        #A pre-funded account on the local development network.
export STARKNET_RPC=http://0.0.0.0:5050 #To specify the network, targeting the local katana devnet.

Then, ensure your project acknowledges the environment variables:

source .env

These settings significantly streamline Starkli command operations, ensuring a smoother and more efficient workflow.

Declare contract

Make sure Katana is already running in separate terminal. Otherwise launch katana

katana --disable-fee

To declare your contract, execute:

starkli declare target/dev/simple_storage_SimpleStorage.contract_class.json

Upon successful command execution, you'll obtain a contract class hash: This unique hash serves as the identifier for your contract class within Starknet.

Sierra compiler version not specified. Attempting to automatically decide version to use...
Unknown network. Falling back to the default compiler version 2.5.4. Use the --compiler-version flag to choose a different version.
Declaring Cairo 1 class: 0x07ad2516dd66fb2e274e78d4357837cad689c9fffaa347feb9800b231b37b306
Compiling Sierra class to CASM with compiler version 2.5.4...
CASM class hash: 0x016052cc70f7462306aa149bdf0e0df3aecb1876a9b05283d60c493c92aa03f4
Contract declaration transaction: 0x0555ba421c2aef3113f1a2d3866955b762191280092bb73956147f24a2d66aa6
Class hash declared:
0x07ad2516dd66fb2e274e78d4357837cad689c9fffaa347feb9800b231b37b306

Deploy contract

starkli deploy <class_hash_of_the_contract_to_be_deployed>

For this contract we did not specified a constructor function, thus we don't need to pass any constructor argument

starkli deploy 0x07ad2516dd66fb2e274e78d4357837cad689c9fffaa347feb9800b231b37b306

After running, expect an output similar to:

Deploying class 0x07ad2516dd66fb2e274e78d4357837cad689c9fffaa347feb9800b231b37b306 with salt 0x02c93ad00ce6f894729baeafd1fd0456c5a5c540c1caa053ab5392f27ea8f130...
The contract will be deployed at address 0x03da69257a94a06a1101c1413d78551e38d91ca180c0fc26004650a427238f4e
Contract deployment transaction: 0x06817bc837ce4df879fe903ca4700a860ce8165742bd74bdadf379618e89cccd
Contract deployed:
0x03da69257a94a06a1101c1413d78551e38d91ca180c0fc26004650a427238f4e

Call contract [only read state]

The first parameter is the contract address, the second parameter is the function to be called.

starkli call 0x03da69257a94a06a1101c1413d78551e38d91ca180c0fc26004650a427238f4e get

After running, expect an output similar to:

[
    "0x0000000000000000000000000000000000000000000000000000000000000000"
]

It means the vale of stored_data is zero.

Invoke contract [can write state]

The first parameter is the contract address, the second parameter is the function to be invoked, and the third parameter is the function parameter. Let's set the value of stored_data to 42.

starkli invoke 0x03da69257a94a06a1101c1413d78551e38d91ca180c0fc26004650a427238f4e set 42

Let's retrieve the new value of stored_data

starkli call 0x03da69257a94a06a1101c1413d78551e38d91ca180c0fc26004650a427238f4e get

After running, expect an output similar to:

[
    "0x000000000000000000000000000000000000000000000000000000000000002a"
]

Awesome you interacted a deployed a raw Cairo smart contract using katana! You can now build more complex smart contracts and interact with them using the same process.