Struct cardano_serialization_lib::MultiAsset

pub struct MultiAsset(_);

Implementations

impl MultiAsset

pub fn to_bytes(&self) -> Vec<u8>

impl MultiAsset

pub fn from_bytes(bytes: Vec<u8>) -> Result<MultiAsset, DeserializeError>

impl MultiAsset

pub fn to_hex(&self) -> String

impl MultiAsset

pub fn from_hex(hex_str: &str) -> Result<MultiAsset, DeserializeError>

impl MultiAsset

pub fn to_json(&self) -> Result<String, JsError>

pub fn from_json(json: &str) -> Result<MultiAsset, JsError>

impl MultiAsset

pub fn new() -> Self

Examples found in repository

src/lib.rs (line 3588)

    fn as_multiasset(&self, is_positive: bool) -> MultiAsset {
        self.0.iter().fold(MultiAsset::new(), |res, e : &(PolicyID, MintAssets) | {
            let assets: Assets = (e.1).0.iter().fold(Assets::new(), |res, e| {
                let mut assets = res;
                if e.1.is_positive() == is_positive {
                    let amount = match is_positive {
                        true => e.1.as_positive(),
                        false => e.1.as_negative(),
                    };
                    assets.insert(&e.0, &amount.unwrap());
                }
                assets
            });
            let mut ma = res;
            if !assets.0.is_empty() {
                ma.insert(&e.0, &assets);
            }
            ma
        })
    }

src/tx_builder/batch_tools/asset_categorizer.rs (line 200)

    pub(crate) fn build_value(&self, used_utxos: &HashSet<UtxoIndex>, tx_output_proposal: &TxOutputProposal)
                              -> Result<Value, JsError> {
        let mut value = Value::new(&tx_output_proposal.total_ada);
        if tx_output_proposal.used_assets.is_empty() {
            return Ok(value);
        }
        let mut multiasset = MultiAsset::new();
        for (policy_index, assets) in &tx_output_proposal.grouped_assets {
            for asset_index in assets {
                let mut asset_coins = Coin::zero();
                for utxo in used_utxos {
                    if let Some(coins) = self.assets_amounts[asset_index.0].get(utxo) {
                        asset_coins = asset_coins.checked_add(coins)?;
                    }
                }
                multiasset.set_asset(&self.policies[policy_index.0], &self.assets[asset_index.0].1, asset_coins);
            }
        }

        value.set_multiasset(&multiasset);
        Ok(value)
    }

src/tx_builder.rs (line 1384)

    pub fn add_change_if_needed(&mut self, address: &Address) -> Result<bool, JsError> {
        let fee = match &self.fee {
            None => self.min_fee(),
            // generating the change output involves changing the fee
            Some(_x) => {
                return Err(JsError::from_str(
                    "Cannot calculate change if fee was explicitly specified",
                ))
            }
        }?;

        // note: can't add plutus data or data hash and script to change
        // because we don't know how many change outputs will need to be created
        let plutus_data: Option<DataOption> = None;
        let script_ref: Option<ScriptRef> = None;

        let input_total = self.get_total_input()?;
        let output_total = self.get_total_output()?;

        let shortage = get_input_shortage(&input_total, &output_total, &fee)?;
        if let Some(shortage) = shortage {
            return Err(JsError::from_str(&format!("Insufficient input in transaction. {}", shortage)));
        }

        use std::cmp::Ordering;
        match &input_total.partial_cmp(&output_total.checked_add(&Value::new(&fee))?) {
            Some(Ordering::Equal) => {
                // recall: min_fee assumed the fee was the maximum possible so we definitely have enough input to cover whatever fee it ends up being
                self.set_fee(&input_total.checked_sub(&output_total)?.coin());
                Ok(false)
            }
            Some(Ordering::Less) => Err(JsError::from_str("Insufficient input in transaction")),
            Some(Ordering::Greater) => {
                fn has_assets(ma: Option<MultiAsset>) -> bool {
                    ma.map(|assets| assets.len() > 0).unwrap_or(false)
                }
                let change_estimator = input_total.checked_sub(&output_total)?;
                if has_assets(change_estimator.multiasset()) {
                    fn will_adding_asset_make_output_overflow(
                        output: &TransactionOutput,
                        current_assets: &Assets,
                        asset_to_add: (PolicyID, AssetName, BigNum),
                        max_value_size: u32,
                        data_cost: &DataCost,
                    ) -> Result<bool, JsError> {
                        let (policy, asset_name, value) = asset_to_add;
                        let mut current_assets_clone = current_assets.clone();
                        current_assets_clone.insert(&asset_name, &value);
                        let mut amount_clone = output.amount.clone();
                        let mut val = Value::new(&Coin::zero());
                        let mut ma = MultiAsset::new();

                        ma.insert(&policy, &current_assets_clone);
                        val.set_multiasset(&ma);
                        amount_clone = amount_clone.checked_add(&val)?;

                        // calculate minADA for more precise max value size
                        let mut calc = MinOutputAdaCalculator::new_empty(data_cost)?;
                        calc.set_amount(&val);
                        let min_ada = calc.calculate_ada()?;
                        amount_clone.set_coin(&min_ada);

                        Ok(amount_clone.to_bytes().len() > max_value_size as usize)
                    }
                    fn pack_nfts_for_change(
                        max_value_size: u32,
                        data_cost: &DataCost,
                        change_address: &Address,
                        change_estimator: &Value,
                        plutus_data: &Option<DataOption>,
                        script_ref: &Option<ScriptRef>,
                    ) -> Result<Vec<MultiAsset>, JsError> {
                        // we insert the entire available ADA temporarily here since that could potentially impact the size
                        // as it could be 1, 2 3 or 4 bytes for Coin.
                        let mut change_assets: Vec<MultiAsset> = Vec::new();

                        let mut base_coin = Value::new(&change_estimator.coin());
                        base_coin.set_multiasset(&MultiAsset::new());
                        let mut output = TransactionOutput {
                            address: change_address.clone(),
                            amount: base_coin.clone(),
                            plutus_data: plutus_data.clone(),
                            script_ref: script_ref.clone(),
                        };
                        // If this becomes slow on large TXs we can optimize it like the following
                        // to avoid cloning + reserializing the entire output.
                        // This would probably be more relevant if we use a smarter packing algorithm
                        // which might need to compare more size differences than greedy
                        //let mut bytes_used = output.to_bytes().len();

                        // a greedy packing is done here to avoid an exponential bin-packing
                        // which in most cases likely shouldn't be the difference between
                        // having an extra change output or not unless there are gigantic
                        // differences in NFT policy sizes
                        for (policy, assets) in change_estimator.multiasset().unwrap().0.iter() {
                            // for simplicity we also don't split assets within a single policy since
                            // you would need to have a very high amoun of assets (which add 1-36 bytes each)
                            // in a single policy to make a difference. In the future if this becomes an issue
                            // we can change that here.

                            // this is the other part of the optimization but we need to take into account
                            // the difference between CBOR encoding which can change which happens in two places:
                            // a) length within assets of one policy id
                            // b) length of the entire multiasset
                            // so for simplicity we will just do it the safe, naive way unless
                            // performance becomes an issue.
                            //let extra_bytes = policy.to_bytes().len() + assets.to_bytes().len() + 2 + cbor_len_diff;
                            //if bytes_used + extra_bytes <= max_value_size as usize {
                            let mut old_amount = output.amount.clone();
                            let mut val = Value::new(&Coin::zero());
                            let mut next_nft = MultiAsset::new();

                            let asset_names = assets.keys();
                            let mut rebuilt_assets = Assets::new();
                            for n in 0..asset_names.len() {
                                let asset_name = asset_names.get(n);
                                let value = assets.get(&asset_name).unwrap();

                                if will_adding_asset_make_output_overflow(
                                    &output,
                                    &rebuilt_assets,
                                    (policy.clone(), asset_name.clone(), value),
                                    max_value_size,
                                    data_cost,
                                )? {
                                    // if we got here, this means we will run into a overflow error,
                                    // so we want to split into multiple outputs, for that we...

                                    // 1. insert the current assets as they are, as this won't overflow
                                    next_nft.insert(policy, &rebuilt_assets);
                                    val.set_multiasset(&next_nft);
                                    output.amount = output.amount.checked_add(&val)?;
                                    change_assets.push(output.amount.multiasset().unwrap());

                                    // 2. create a new output with the base coin value as zero
                                    base_coin = Value::new(&Coin::zero());
                                    base_coin.set_multiasset(&MultiAsset::new());
                                    output = TransactionOutput {
                                        address: change_address.clone(),
                                        amount: base_coin.clone(),
                                        plutus_data: plutus_data.clone(),
                                        script_ref: script_ref.clone(),
                                    };

                                    // 3. continue building the new output from the asset we stopped
                                    old_amount = output.amount.clone();
                                    val = Value::new(&Coin::zero());
                                    next_nft = MultiAsset::new();

                                    rebuilt_assets = Assets::new();
                                }

                                rebuilt_assets.insert(&asset_name, &value);
                            }

                            next_nft.insert(policy, &rebuilt_assets);
                            val.set_multiasset(&next_nft);
                            output.amount = output.amount.checked_add(&val)?;

                            // calculate minADA for more precise max value size
                            let mut amount_clone = output.amount.clone();
                            let mut calc = MinOutputAdaCalculator::new_empty(data_cost)?;
                            calc.set_amount(&val);
                            let min_ada = calc.calculate_ada()?;
                            amount_clone.set_coin(&min_ada);

                            if amount_clone.to_bytes().len() > max_value_size as usize {
                                output.amount = old_amount;
                                break;
                            }
                        }
                        change_assets.push(output.amount.multiasset().unwrap());
                        Ok(change_assets)
                    }
                    let mut change_left = input_total.checked_sub(&output_total)?;
                    let mut new_fee = fee.clone();
                    // we might need multiple change outputs for cases where the change has many asset types
                    // which surpass the max UTXO size limit
                    let utxo_cost = self.config.utxo_cost();
                    let mut calc = MinOutputAdaCalculator::new_empty(&utxo_cost)?;
                    if let Some(data) = &plutus_data {
                        match data {
                            DataOption::DataHash(data_hash) => calc.set_data_hash(data_hash),
                            DataOption::Data(datum) => calc.set_plutus_data(datum),
                        };
                    }
                    if let Some(script_ref) = &script_ref {
                        calc.set_script_ref(script_ref);
                    }
                    let minimum_utxo_val = calc.calculate_ada()?;
                    while let Some(Ordering::Greater) = change_left
                        .multiasset
                        .as_ref()
                        .map_or_else(|| None, |ma| ma.partial_cmp(&MultiAsset::new()))
                    {
                        let nft_changes = pack_nfts_for_change(
                            self.config.max_value_size,
                            &utxo_cost,
                            address,
                            &change_left,
                            &plutus_data.clone(),
                            &script_ref.clone(),
                        )?;
                        if nft_changes.len() == 0 {
                            // this likely should never happen
                            return Err(JsError::from_str("NFTs too large for change output"));
                        }
                        // we only add the minimum needed (for now) to cover this output
                        let mut change_value = Value::new(&Coin::zero());
                        for nft_change in nft_changes.iter() {
                            change_value.set_multiasset(&nft_change);
                            let mut calc = MinOutputAdaCalculator::new_empty(&utxo_cost)?;
                            //TODO add precise calculation
                            let mut fake_change = change_value.clone();
                            fake_change.set_coin(&change_left.coin);
                            calc.set_amount(&fake_change);
                            if let Some(data) = &plutus_data {
                                match data {
                                    DataOption::DataHash(data_hash) => {
                                        calc.set_data_hash(data_hash)
                                    }
                                    DataOption::Data(datum) => calc.set_plutus_data(datum),
                                };
                            }
                            if let Some(script_ref) = &script_ref {
                                calc.set_script_ref(script_ref);
                            }
                            let min_ada = calc.calculate_ada()?;
                            change_value.set_coin(&min_ada);
                            let change_output = TransactionOutput {
                                address: address.clone(),
                                amount: change_value.clone(),
                                plutus_data: plutus_data.clone(),
                                script_ref: script_ref.clone(),
                            };

                            // increase fee
                            let fee_for_change = self.fee_for_output(&change_output)?;
                            new_fee = new_fee.checked_add(&fee_for_change)?;
                            if change_left.coin() < min_ada.checked_add(&new_fee)? {
                                return Err(JsError::from_str("Not enough ADA leftover to include non-ADA assets in a change address"));
                            }
                            change_left = change_left.checked_sub(&change_value)?;
                            self.add_output(&change_output)?;
                        }
                    }
                    change_left = change_left.checked_sub(&Value::new(&new_fee))?;
                    // add potentially a separate pure ADA change output
                    let left_above_minimum = change_left.coin.compare(&minimum_utxo_val) > 0;
                    if self.config.prefer_pure_change && left_above_minimum {
                        let pure_output = TransactionOutput {
                            address: address.clone(),
                            amount: change_left.clone(),
                            plutus_data: plutus_data.clone(),
                            script_ref: script_ref.clone(),
                        };
                        let additional_fee = self.fee_for_output(&pure_output)?;
                        let potential_pure_value =
                            change_left.checked_sub(&Value::new(&additional_fee))?;
                        let potential_pure_above_minimum =
                            potential_pure_value.coin.compare(&minimum_utxo_val) > 0;
                        if potential_pure_above_minimum {
                            new_fee = new_fee.checked_add(&additional_fee)?;
                            change_left = Value::zero();
                            self.add_output(&TransactionOutput {
                                address: address.clone(),
                                amount: potential_pure_value.clone(),
                                plutus_data: plutus_data.clone(),
                                script_ref: script_ref.clone(),
                            })?;
                        }
                    }
                    self.set_fee(&new_fee);
                    // add in the rest of the ADA
                    if !change_left.is_zero() {
                        self.outputs.0.last_mut().unwrap().amount = self
                            .outputs
                            .0
                            .last()
                            .unwrap()
                            .amount
                            .checked_add(&change_left)?;
                    }
                    Ok(true)
                } else {
                    let mut calc = MinOutputAdaCalculator::new_empty(&self.config.utxo_cost())?;
                    calc.set_amount(&change_estimator);
                    if let Some(data) = &plutus_data {
                        match data {
                            DataOption::DataHash(data_hash) => calc.set_data_hash(data_hash),
                            DataOption::Data(datum) => calc.set_plutus_data(datum),
                        };
                    }
                    if let Some(script_ref) = &script_ref {
                        calc.set_script_ref(script_ref);
                    }
                    let min_ada = calc.calculate_ada()?;

                    // no-asset case so we have no problem burning the rest if there is no other option
                    fn burn_extra(
                        builder: &mut TransactionBuilder,
                        burn_amount: &BigNum,
                    ) -> Result<bool, JsError> {
                        // recall: min_fee assumed the fee was the maximum possible so we definitely have enough input to cover whatever fee it ends up being
                        builder.set_fee(burn_amount);
                        Ok(false) // not enough input to covert the extra fee from adding an output so we just burn whatever is left
                    }
                    match change_estimator.coin() >= min_ada {
                        false => burn_extra(self, &change_estimator.coin()),
                        true => {
                            // check how much the fee would increase if we added a change output
                            let fee_for_change = self.fee_for_output(&TransactionOutput {
                                address: address.clone(),
                                amount: change_estimator.clone(),
                                plutus_data: plutus_data.clone(),
                                script_ref: script_ref.clone(),
                            })?;

                            let new_fee = fee.checked_add(&fee_for_change)?;
                            match change_estimator.coin()
                                >= min_ada.checked_add(&Value::new(&new_fee).coin())?
                            {
                                false => burn_extra(self, &change_estimator.coin()),
                                true => {
                                    // recall: min_fee assumed the fee was the maximum possible so we definitely have enough input to cover whatever fee it ends up being
                                    self.set_fee(&new_fee);

                                    self.add_output(&TransactionOutput {
                                        address: address.clone(),
                                        amount: change_estimator
                                            .checked_sub(&Value::new(&new_fee.clone()))?,
                                        plutus_data: plutus_data.clone(),
                                        script_ref: script_ref.clone(),
                                    })?;

                                    Ok(true)
                                }
                            }
                        }
                    }
                }
            }
            None => Err(JsError::from_str(
                "missing input or output for some native asset",
            )),
        }
    }

src/utils.rs (line 437)

    pub fn checked_add(&self, rhs: &Value) -> Result<Value, JsError> {
        use std::collections::btree_map::Entry;
        let coin = self.coin.checked_add(&rhs.coin)?;

        let multiasset = match (&self.multiasset, &rhs.multiasset) {
            (Some(lhs_multiasset), Some(rhs_multiasset)) => {
                let mut multiasset = MultiAsset::new();

                for ma in &[lhs_multiasset, rhs_multiasset] {
                    for (policy, assets) in &ma.0 {
                        for (asset_name, amount) in &assets.0 {
                            match multiasset.0.entry(policy.clone()) {
                                Entry::Occupied(mut assets) => {
                                    match assets.get_mut().0.entry(asset_name.clone()) {
                                        Entry::Occupied(mut assets) => {
                                            let current = assets.get_mut();
                                            *current = current.checked_add(&amount)?;
                                        }
                                        Entry::Vacant(vacant_entry) => {
                                            vacant_entry.insert(amount.clone());
                                        }
                                    }
                                }
                                Entry::Vacant(entry) => {
                                    let mut assets = Assets::new();
                                    assets.0.insert(asset_name.clone(), amount.clone());
                                    entry.insert(assets);
                                }
                            }
                        }
                    }
                }

                Some(multiasset)
            }
            (None, None) => None,
            (Some(ma), None) => Some(ma.clone()),
            (None, Some(ma)) => Some(ma.clone()),
        };

        Ok(Value { coin, multiasset })
    }

    pub fn checked_sub(&self, rhs_value: &Value) -> Result<Value, JsError> {
        let coin = self.coin.checked_sub(&rhs_value.coin)?;
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Ok(Value { coin, multiasset })
    }

    pub fn clamped_sub(&self, rhs_value: &Value) -> Value {
        let coin = self.coin.clamped_sub(&rhs_value.coin);
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Value { coin, multiasset }
    }

    /// note: values are only partially comparable
    pub fn compare(&self, rhs_value: &Value) -> Option<i8> {
        match self.partial_cmp(&rhs_value) {
            None => None,
            Some(std::cmp::Ordering::Equal) => Some(0),
            Some(std::cmp::Ordering::Less) => Some(-1),
            Some(std::cmp::Ordering::Greater) => Some(1),
        }
    }
}

impl PartialOrd for Value {
    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
        use std::cmp::Ordering::*;

        fn compare_assets(
            lhs: &Option<MultiAsset>,
            rhs: &Option<MultiAsset>,
        ) -> Option<std::cmp::Ordering> {
            match (lhs, rhs) {
                (None, None) => Some(Equal),
                (None, Some(rhs_assets)) => MultiAsset::new().partial_cmp(&rhs_assets),
                (Some(lhs_assets), None) => lhs_assets.partial_cmp(&MultiAsset::new()),
                (Some(lhs_assets), Some(rhs_assets)) => lhs_assets.partial_cmp(&rhs_assets),
            }
        }

pub fn len(&self) -> usize

the number of unique policy IDs in the multiasset

Examples found in repository

src/tx_builder.rs (line 1368)

                fn has_assets(ma: Option<MultiAsset>) -> bool {
                    ma.map(|assets| assets.len() > 0).unwrap_or(false)
                }

src/utils.rs (line 411)

    pub fn is_zero(&self) -> bool {
        self.coin.is_zero()
            && self
            .multiasset
            .as_ref()
            .map(|m| m.len() == 0)
            .unwrap_or(true)
    }

    pub fn coin(&self) -> Coin {
        self.coin
    }

    pub fn set_coin(&mut self, coin: &Coin) {
        self.coin = coin.clone();
    }

    pub fn multiasset(&self) -> Option<MultiAsset> {
        self.multiasset.clone()
    }

    pub fn set_multiasset(&mut self, multiasset: &MultiAsset) {
        self.multiasset = Some(multiasset.clone());
    }

    pub fn checked_add(&self, rhs: &Value) -> Result<Value, JsError> {
        use std::collections::btree_map::Entry;
        let coin = self.coin.checked_add(&rhs.coin)?;

        let multiasset = match (&self.multiasset, &rhs.multiasset) {
            (Some(lhs_multiasset), Some(rhs_multiasset)) => {
                let mut multiasset = MultiAsset::new();

                for ma in &[lhs_multiasset, rhs_multiasset] {
                    for (policy, assets) in &ma.0 {
                        for (asset_name, amount) in &assets.0 {
                            match multiasset.0.entry(policy.clone()) {
                                Entry::Occupied(mut assets) => {
                                    match assets.get_mut().0.entry(asset_name.clone()) {
                                        Entry::Occupied(mut assets) => {
                                            let current = assets.get_mut();
                                            *current = current.checked_add(&amount)?;
                                        }
                                        Entry::Vacant(vacant_entry) => {
                                            vacant_entry.insert(amount.clone());
                                        }
                                    }
                                }
                                Entry::Vacant(entry) => {
                                    let mut assets = Assets::new();
                                    assets.0.insert(asset_name.clone(), amount.clone());
                                    entry.insert(assets);
                                }
                            }
                        }
                    }
                }

                Some(multiasset)
            }
            (None, None) => None,
            (Some(ma), None) => Some(ma.clone()),
            (None, Some(ma)) => Some(ma.clone()),
        };

        Ok(Value { coin, multiasset })
    }

    pub fn checked_sub(&self, rhs_value: &Value) -> Result<Value, JsError> {
        let coin = self.coin.checked_sub(&rhs_value.coin)?;
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Ok(Value { coin, multiasset })
    }

    pub fn clamped_sub(&self, rhs_value: &Value) -> Value {
        let coin = self.coin.clamped_sub(&rhs_value.coin);
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Value { coin, multiasset }
    }

pub fn insert(&mut self, policy_id: &PolicyID, assets: &Assets) -> Option<Assets>

set (and replace if it exists) all assets with policy {policy_id} to a copy of {assets}

Examples found in repository

src/lib.rs (line 3602)

    fn as_multiasset(&self, is_positive: bool) -> MultiAsset {
        self.0.iter().fold(MultiAsset::new(), |res, e : &(PolicyID, MintAssets) | {
            let assets: Assets = (e.1).0.iter().fold(Assets::new(), |res, e| {
                let mut assets = res;
                if e.1.is_positive() == is_positive {
                    let amount = match is_positive {
                        true => e.1.as_positive(),
                        false => e.1.as_negative(),
                    };
                    assets.insert(&e.0, &amount.unwrap());
                }
                assets
            });
            let mut ma = res;
            if !assets.0.is_empty() {
                ma.insert(&e.0, &assets);
            }
            ma
        })
    }

src/tx_builder.rs (line 1386)

                    fn will_adding_asset_make_output_overflow(
                        output: &TransactionOutput,
                        current_assets: &Assets,
                        asset_to_add: (PolicyID, AssetName, BigNum),
                        max_value_size: u32,
                        data_cost: &DataCost,
                    ) -> Result<bool, JsError> {
                        let (policy, asset_name, value) = asset_to_add;
                        let mut current_assets_clone = current_assets.clone();
                        current_assets_clone.insert(&asset_name, &value);
                        let mut amount_clone = output.amount.clone();
                        let mut val = Value::new(&Coin::zero());
                        let mut ma = MultiAsset::new();

                        ma.insert(&policy, &current_assets_clone);
                        val.set_multiasset(&ma);
                        amount_clone = amount_clone.checked_add(&val)?;

                        // calculate minADA for more precise max value size
                        let mut calc = MinOutputAdaCalculator::new_empty(data_cost)?;
                        calc.set_amount(&val);
                        let min_ada = calc.calculate_ada()?;
                        amount_clone.set_coin(&min_ada);

                        Ok(amount_clone.to_bytes().len() > max_value_size as usize)
                    }
                    fn pack_nfts_for_change(
                        max_value_size: u32,
                        data_cost: &DataCost,
                        change_address: &Address,
                        change_estimator: &Value,
                        plutus_data: &Option<DataOption>,
                        script_ref: &Option<ScriptRef>,
                    ) -> Result<Vec<MultiAsset>, JsError> {
                        // we insert the entire available ADA temporarily here since that could potentially impact the size
                        // as it could be 1, 2 3 or 4 bytes for Coin.
                        let mut change_assets: Vec<MultiAsset> = Vec::new();

                        let mut base_coin = Value::new(&change_estimator.coin());
                        base_coin.set_multiasset(&MultiAsset::new());
                        let mut output = TransactionOutput {
                            address: change_address.clone(),
                            amount: base_coin.clone(),
                            plutus_data: plutus_data.clone(),
                            script_ref: script_ref.clone(),
                        };
                        // If this becomes slow on large TXs we can optimize it like the following
                        // to avoid cloning + reserializing the entire output.
                        // This would probably be more relevant if we use a smarter packing algorithm
                        // which might need to compare more size differences than greedy
                        //let mut bytes_used = output.to_bytes().len();

                        // a greedy packing is done here to avoid an exponential bin-packing
                        // which in most cases likely shouldn't be the difference between
                        // having an extra change output or not unless there are gigantic
                        // differences in NFT policy sizes
                        for (policy, assets) in change_estimator.multiasset().unwrap().0.iter() {
                            // for simplicity we also don't split assets within a single policy since
                            // you would need to have a very high amoun of assets (which add 1-36 bytes each)
                            // in a single policy to make a difference. In the future if this becomes an issue
                            // we can change that here.

                            // this is the other part of the optimization but we need to take into account
                            // the difference between CBOR encoding which can change which happens in two places:
                            // a) length within assets of one policy id
                            // b) length of the entire multiasset
                            // so for simplicity we will just do it the safe, naive way unless
                            // performance becomes an issue.
                            //let extra_bytes = policy.to_bytes().len() + assets.to_bytes().len() + 2 + cbor_len_diff;
                            //if bytes_used + extra_bytes <= max_value_size as usize {
                            let mut old_amount = output.amount.clone();
                            let mut val = Value::new(&Coin::zero());
                            let mut next_nft = MultiAsset::new();

                            let asset_names = assets.keys();
                            let mut rebuilt_assets = Assets::new();
                            for n in 0..asset_names.len() {
                                let asset_name = asset_names.get(n);
                                let value = assets.get(&asset_name).unwrap();

                                if will_adding_asset_make_output_overflow(
                                    &output,
                                    &rebuilt_assets,
                                    (policy.clone(), asset_name.clone(), value),
                                    max_value_size,
                                    data_cost,
                                )? {
                                    // if we got here, this means we will run into a overflow error,
                                    // so we want to split into multiple outputs, for that we...

                                    // 1. insert the current assets as they are, as this won't overflow
                                    next_nft.insert(policy, &rebuilt_assets);
                                    val.set_multiasset(&next_nft);
                                    output.amount = output.amount.checked_add(&val)?;
                                    change_assets.push(output.amount.multiasset().unwrap());

                                    // 2. create a new output with the base coin value as zero
                                    base_coin = Value::new(&Coin::zero());
                                    base_coin.set_multiasset(&MultiAsset::new());
                                    output = TransactionOutput {
                                        address: change_address.clone(),
                                        amount: base_coin.clone(),
                                        plutus_data: plutus_data.clone(),
                                        script_ref: script_ref.clone(),
                                    };

                                    // 3. continue building the new output from the asset we stopped
                                    old_amount = output.amount.clone();
                                    val = Value::new(&Coin::zero());
                                    next_nft = MultiAsset::new();

                                    rebuilt_assets = Assets::new();
                                }

                                rebuilt_assets.insert(&asset_name, &value);
                            }

                            next_nft.insert(policy, &rebuilt_assets);
                            val.set_multiasset(&next_nft);
                            output.amount = output.amount.checked_add(&val)?;

                            // calculate minADA for more precise max value size
                            let mut amount_clone = output.amount.clone();
                            let mut calc = MinOutputAdaCalculator::new_empty(data_cost)?;
                            calc.set_amount(&val);
                            let min_ada = calc.calculate_ada()?;
                            amount_clone.set_coin(&min_ada);

                            if amount_clone.to_bytes().len() > max_value_size as usize {
                                output.amount = old_amount;
                                break;
                            }
                        }
                        change_assets.push(output.amount.multiasset().unwrap());
                        Ok(change_assets)
                    }

pub fn get(&self, policy_id: &PolicyID) -> Option<Assets>

all assets under {policy_id}, if any exist, or else None (undefined in JS)

Examples found in repository

src/lib.rs (line 3433)

        fn amount_or_zero(ma: &MultiAsset, pid: &PolicyID, aname: &AssetName) -> Coin {
            ma.get(&pid)
                .and_then(|assets| assets.get(aname))
                .unwrap_or(to_bignum(0u64)) // assume 0 if asset not present
        }

src/tx_builder.rs (line 461)

    pub fn add_inputs_from(
        &mut self,
        inputs: &TransactionUnspentOutputs,
        strategy: CoinSelectionStrategyCIP2,
    ) -> Result<(), JsError> {
        let available_inputs = &inputs.0.clone();
        let mut input_total = self.get_total_input()?;
        let mut output_total = self
            .get_total_output()?
            .checked_add(&Value::new(&self.min_fee()?))?;
        match strategy {
            CoinSelectionStrategyCIP2::LargestFirst => {
                if self
                    .outputs
                    .0
                    .iter()
                    .any(|output| output.amount.multiasset.is_some())
                {
                    return Err(JsError::from_str("Multiasset values not supported by LargestFirst. Please use LargestFirstMultiAsset"));
                }
                self.cip2_largest_first_by(
                    available_inputs,
                    &mut (0..available_inputs.len()).collect(),
                    &mut input_total,
                    &mut output_total,
                    |value| Some(value.coin),
                )?;
            }
            CoinSelectionStrategyCIP2::RandomImprove => {
                if self
                    .outputs
                    .0
                    .iter()
                    .any(|output| output.amount.multiasset.is_some())
                {
                    return Err(JsError::from_str("Multiasset values not supported by RandomImprove. Please use RandomImproveMultiAsset"));
                }
                use rand::Rng;
                let mut rng = rand::thread_rng();
                let mut available_indices =
                    (0..available_inputs.len()).collect::<BTreeSet<usize>>();
                self.cip2_random_improve_by(
                    available_inputs,
                    &mut available_indices,
                    &mut input_total,
                    &mut output_total,
                    |value| Some(value.coin),
                    &mut rng,
                    true,
                )?;
                // Phase 3: add extra inputs needed for fees (not covered by CIP-2)
                // We do this at the end because this new inputs won't be associated with
                // a specific output, so the improvement algorithm we do above does not apply here.
                while input_total.coin < output_total.coin {
                    if available_indices.is_empty() {
                        return Err(JsError::from_str("UTxO Balance Insufficient[x]"));
                    }
                    let i = *available_indices
                        .iter()
                        .nth(rng.gen_range(0..available_indices.len()))
                        .unwrap();
                    available_indices.remove(&i);
                    let input = &available_inputs[i];
                    let input_fee = self.fee_for_input(
                        &input.output.address,
                        &input.input,
                        &input.output.amount,
                    )?;
                    self.add_input(&input.output.address, &input.input, &input.output.amount);
                    input_total = input_total.checked_add(&input.output.amount)?;
                    output_total = output_total.checked_add(&Value::new(&input_fee))?;
                }
            }
            CoinSelectionStrategyCIP2::LargestFirstMultiAsset => {
                // indices into {available_inputs} for inputs that contain {policy_id}:{asset_name}
                let mut available_indices = (0..available_inputs.len()).collect::<Vec<usize>>();
                // run largest-fist by each asset type
                if let Some(ma) = output_total.multiasset.clone() {
                    for (policy_id, assets) in ma.0.iter() {
                        for (asset_name, _) in assets.0.iter() {
                            self.cip2_largest_first_by(
                                available_inputs,
                                &mut available_indices,
                                &mut input_total,
                                &mut output_total,
                                |value| value.multiasset.as_ref()?.get(policy_id)?.get(asset_name),
                            )?;
                        }
                    }
                }
                // add in remaining ADA
                self.cip2_largest_first_by(
                    available_inputs,
                    &mut available_indices,
                    &mut input_total,
                    &mut output_total,
                    |value| Some(value.coin),
                )?;
            }
            CoinSelectionStrategyCIP2::RandomImproveMultiAsset => {
                use rand::Rng;
                let mut rng = rand::thread_rng();
                let mut available_indices =
                    (0..available_inputs.len()).collect::<BTreeSet<usize>>();
                // run random-improve by each asset type
                if let Some(ma) = output_total.multiasset.clone() {
                    for (policy_id, assets) in ma.0.iter() {
                        for (asset_name, _) in assets.0.iter() {
                            self.cip2_random_improve_by(
                                available_inputs,
                                &mut available_indices,
                                &mut input_total,
                                &mut output_total,
                                |value| value.multiasset.as_ref()?.get(policy_id)?.get(asset_name),
                                &mut rng,
                                false,
                            )?;
                        }
                    }
                }
                // add in remaining ADA
                self.cip2_random_improve_by(
                    available_inputs,
                    &mut available_indices,
                    &mut input_total,
                    &mut output_total,
                    |value| Some(value.coin),
                    &mut rng,
                    false,
                )?;
                // Phase 3: add extra inputs needed for fees (not covered by CIP-2)
                // We do this at the end because this new inputs won't be associated with
                // a specific output, so the improvement algorithm we do above does not apply here.
                while input_total.coin < output_total.coin {
                    if available_indices.is_empty() {
                        return Err(JsError::from_str("UTxO Balance Insufficient[x]"));
                    }
                    let i = *available_indices
                        .iter()
                        .nth(rng.gen_range(0..available_indices.len()))
                        .unwrap();
                    available_indices.remove(&i);
                    let input = &available_inputs[i];
                    let input_fee = self.fee_for_input(
                        &input.output.address,
                        &input.input,
                        &input.output.amount,
                    )?;
                    self.add_input(&input.output.address, &input.input, &input.output.amount);
                    input_total = input_total.checked_add(&input.output.amount)?;
                    output_total = output_total.checked_add(&Value::new(&input_fee))?;
                }
            }
        }

        Ok(())
    }

pub fn set_asset(
    &mut self,
    policy_id: &PolicyID,
    asset_name: &AssetName,
    value: BigNum
) -> Option<BigNum>

sets the asset {asset_name} to {value} under policy {policy_id} returns the previous amount if it was set, or else None (undefined in JS)

Examples found in repository

src/tx_builder/batch_tools/asset_categorizer.rs (line 209)

    pub(crate) fn build_value(&self, used_utxos: &HashSet<UtxoIndex>, tx_output_proposal: &TxOutputProposal)
                              -> Result<Value, JsError> {
        let mut value = Value::new(&tx_output_proposal.total_ada);
        if tx_output_proposal.used_assets.is_empty() {
            return Ok(value);
        }
        let mut multiasset = MultiAsset::new();
        for (policy_index, assets) in &tx_output_proposal.grouped_assets {
            for asset_index in assets {
                let mut asset_coins = Coin::zero();
                for utxo in used_utxos {
                    if let Some(coins) = self.assets_amounts[asset_index.0].get(utxo) {
                        asset_coins = asset_coins.checked_add(coins)?;
                    }
                }
                multiasset.set_asset(&self.policies[policy_index.0], &self.assets[asset_index.0].1, asset_coins);
            }
        }

        value.set_multiasset(&multiasset);
        Ok(value)
    }

pub fn get_asset(&self, policy_id: &PolicyID, asset_name: &AssetName) -> BigNum

returns the amount of asset {asset_name} under policy {policy_id} If such an asset does not exist, 0 is returned.

Examples found in repository

src/utils.rs (line 1684)

pub(crate) fn get_input_shortage(all_inputs_value: &Value, all_outputs_value: &Value, fee: &Coin)
    -> Result<Option<ValueShortage>, JsError> {
    let mut shortage = ValueShortage{
        ada_shortage: None,
        asset_shortage: Vec::new()};
    if all_inputs_value.coin < all_outputs_value.coin.checked_add(fee)? {
        shortage.ada_shortage = Some((
            all_inputs_value.coin.clone(),
            all_outputs_value.coin.clone(),
            fee.clone()));
    }

    if let Some(policies) = &all_outputs_value.multiasset {
        for (policy_id, assets) in &policies.0 {
            for (asset_name, coins) in &assets.0 {
                let inputs_coins = match &all_inputs_value.multiasset {
                    Some(multiasset) => multiasset.get_asset(policy_id, asset_name),
                    None => Coin::zero()
                };

                if inputs_coins < *coins {
                    shortage.asset_shortage.push((policy_id.clone(), asset_name.clone(), inputs_coins, coins.clone()));
                }
            }
        }
    }

    if shortage.ada_shortage.is_some() || shortage.asset_shortage.len() > 0 {
        Ok(Some(shortage))
    } else {
        Ok(None)
    }
}

pub fn keys(&self) -> PolicyIDs

returns all policy IDs used by assets in this multiasset

pub fn sub(&self, rhs_ma: &MultiAsset) -> MultiAsset

removes an asset from the list if the result is 0 or less does not modify this object, instead the result is returned

Examples found in repository

src/utils.rs (line 477)

    pub fn checked_sub(&self, rhs_value: &Value) -> Result<Value, JsError> {
        let coin = self.coin.checked_sub(&rhs_value.coin)?;
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Ok(Value { coin, multiasset })
    }

    pub fn clamped_sub(&self, rhs_value: &Value) -> Value {
        let coin = self.coin.clamped_sub(&rhs_value.coin);
        let multiasset = match (&self.multiasset, &rhs_value.multiasset) {
            (Some(lhs_ma), Some(rhs_ma)) => match lhs_ma.sub(rhs_ma).len() {
                0 => None,
                _ => Some(lhs_ma.sub(rhs_ma)),
            },
            (Some(lhs_ma), None) => Some(lhs_ma.clone()),
            (None, Some(_rhs_ma)) => None,
            (None, None) => None,
        };

        Value { coin, multiasset }
    }

Trait Implementations

impl Clone for MultiAsset

fn clone(&self) -> MultiAsset

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MultiAsset

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for MultiAsset

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>where
    __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Deserialize for MultiAsset

fn deserialize<R: BufRead + Seek>(
    raw: &mut Deserializer<R>
) -> Result<Self, DeserializeError>

impl JsonSchema for MultiAsset

fn schema_name() -> String

The name of the generated JSON Schema.

fn json_schema(gen: &mut SchemaGenerator) -> Schema

Generates a JSON Schema for this type.

fn is_referenceable() -> bool

Whether JSON Schemas generated for this type should be re-used where possible using the $ref keyword.

impl Ord for MultiAsset

fn cmp(&self, other: &MultiAsset) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Selfwhere
    Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Selfwhere
    Self: Sized + PartialOrd<Self>,

Restrict a value to a certain interval.

impl PartialEq<MultiAsset> for MultiAsset

fn eq(&self, other: &MultiAsset) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd<MultiAsset> for MultiAsset

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for MultiAsset

fn serialize<'se, W: Write>(
    &self,
    serializer: &'se mut Serializer<W>
) -> Result<&'se mut Serializer<W>>

impl Serialize for MultiAsset

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>where
    __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for MultiAsset

impl StructuralEq for MultiAsset

impl StructuralPartialEq for MultiAsset