Marlowe Lang

An experimental Rust implementation of the Marlowe DSL for Cardano smart (financial) contracts.

Warning: This crate should not (yet) be used anywhere near a production environment.

Notes regarding marlowe version changes

• The Marlowe playground does not yet support using using address for parties, so if you want to parse contracts created from there, you need to use v 1.12 or convert them manually.

• Not all example data for datums, redeemers or contracts in the iohk cardano-marlowe lib has been updated to use address but still uses PK for parties: if you want to parse those, use v 1.12.

• Same with old marlowe instances on-chain: will not be possible to parse datum or redeemer using v 1.13+.

Main Features

• Encode/Decode Marlowe types between: MarloweDSL/Rust/Json/CborHex
• List contract parameters used in a contract (extended marlowe)
• Initialization of contract parameters (extended-marlowe).

Unstable features

• enabled via the 'unstable' feature.
• Contract simulation (semantics::ContractInstance)
• List expected input actions (semantics::ContractInstance)

To do's

• Add marlowe-spec-test to build pipeline when it has been properly packaged.

Example usages

// Describing a contract in Rust ```rust pub fn basic_example() {

use crate::types::marlowe_without_holes::*;

let p1 = Party::Role { role_token: "P1".into() };
let p2 = Party::Role { role_token: "P2".into() };
let tok = Token::ada();
let quantity = Value::ConstantValue(42000000);

let contract = Contract::When { 
    when: vec![
        Case { 
            case: Action::Deposit { 
                into_account: p2.clone(), 
                party: p1.clone(), 
                of_token: tok, 
                deposits: quantity
            }, 
            then: 
                Contract::Pay { 
                    from_account: p1, 
                    to: Payee::Party(p2), 
                    token: Token::ada(), 
                    pay: Value::ConstantValue(42), 
                    then: Contract::Close.into()
                } 
        }
    ], 
    timeout: Timeout::TimeConstant(999999999), 
    timeout_continuation: Contract::Close.into()
};

println!("{}",crate::parsing::serialization::marlowe::serialize(contract.into()));

} ```

CLI Tool:

Installation:

bash rustup default nightly cargo install marlowe_lang

Examples

marlowelangcli -h

```text Usage: marlowelangcli

Commands: datum Tools for working with datums state Tools for working with state redeemer Tools for working with inputs/redeemers (marlowe actions) contract Tools for working with contracts plutus-data Tools for working with unknown plutus data help Print this message or the help of the given subcommand(s)

Options: -h, --help Print help information -V, --version Print version information ```

marlowelangcli decoding a datum

``text ./marlowe_lang datum from-string 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 cbor-hex detailed-text

State: (MarloweDatumState Accounts([{ (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx"),(Token "" ""),3000000 },]) Bound_Values({}) Choices({}) MinTime(1))

Continuation: Contract (Marlowe-DSL): When [ (Case (Deposit (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx") (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx") (Token "a7f7e57db27c9e2f80c205ccb30f73e57f0ee8fc21aff7b86b5daf78" "Globe") (Constant 300)) (When [ (Case (Deposit (Address "addr1v87n0zzth5zycuh972w7rdmh48qur4f3wu6ntn2m2h30dlchhlqt3") (Address "addr1v87n0zzth5zycuh972w7rdmh48qur4f3wu6ntn2m2h30dlchhlqt3") (Token "ecc8ad61b973946ee1cc666b259acabb3edf38a73f1b8779d93ba28a" "Swan") (Constant 500)) (Pay (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx") (Party (Address "addr1v87n0zzth5zycuh972w7rdmh48qur4f3wu6ntn2m2h30dlchhlqt3")) (Token "a7f7e57db27c9e2f80c205ccb30f73e57f0ee8fc21aff7b86b5daf78" "Globe") (Constant 300) (Pay (Address "addr1v87n0zzth5zycuh972w7rdmh48qur4f3wu6ntn2m2h30dlchhlqt3") (Party (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx")) (Token "ecc8ad61b973946ee1cc666b259acabb3edf38a73f1b8779d93ba28a" "Swan") (Constant 500) Close))) ] 1664414983000 Close)) ] 1664371783000 Close ```

marlowelangcli decoding redeemer / input actions

```text ./marlowe_lang redeemer from-string 9fd8799fd8799fd8799fd87a80d8799fd8799f581c1cb51be3ab4e4b540e86bd4c9be02682db8150f69c3cded2422cc1bfffd87a80ffffd8799fd87a80d8799fd8799f581c1cb51be3ab4e4b540e86bd4c9be02682db8150f69c3cded2422cc1bfffd87a80ffffd8799f581ca7f7e57db27c9e2f80c205ccb30f73e57f0ee8fc21aff7b86b5daf7845476c6f6265ff19012cffffff cbor-hex marlowe-dsl

RESULT: (Deposit (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx") (Address "addr1vywt2xlr4d8yk4qws675exlqy6pdhq2s76wrehkjggkvr0czta9gx") (Token "a7f7e57db27c9e2f80c205ccb30f73e57f0ee8fc21aff7b86b5daf78" "Globe") 300) ```

marlowelangcli query contract for expected inputs

marlowe_lang_clicontract from-file .\test_data\swap.marlowe marlowe-dsl expected-actions -i "Timeout for Ada deposit=9999999999,Amount of Ada=4994,Amount of dollars=99,Timeout for dollar deposit=994"`

Log output:
--> INITIALIZED BY MARLOWE LANG STATE MACHINE AT 1672581873
--> Processing When contract

Result (current contract state): json { "WaitingForInput": [ { "Deposit": { "who_is_expected_to_pay": { "role_token": "Ada provider" }, "expected_asset_type": { "token_name": "", "currency_symbol": "" }, "expected_amount": { "and": 4994, "add": 1000000 }, "expected_target_account": { "account": { "role_token": "Ada provider" } }, "continuation": { "when": [ ... // removed from example output for brevity ], "timeout_continuation": "close", "timeout": 994 } } } ] }