Reserved Attributes

Certain attribute names are reserved exclusively for specific purposes. Please use them only for their intended applications. Attribute names are unique: if the same attribute is set twice, the value will be overwritten.

Static Attributes

The following attributes names are reserved and must be given using ProtocolComponent.static_att. These attributes MUST be immutable.

1. manual_updates

Description

Determines whether the component updates should be manually triggered using the update_marker state attribute. By default, updates occur automatically whenever there is a change indexed for any of the required contracts. For contracts with frequent changes, automatic updates may not be desirable. For instance, a change in Balancer Vault storage should only trigger updates for the specific pools affected by the change, rather than for all pools indiscriminately. The manual_updates field helps to control and prevent unnecessary updates in such cases.

If it's enable, updates on this component are only triggered by emitting an update_marker state attribute (described below).

Type

Set to [1u8]to enable manual updates.

Example Usage

Attribute {
    name: "manual_updates".to_string(),
    value: [1u8],
    change: ChangeType::Creation.into(),
}

2. pool_id

Description

The pool_id static attribute is used to specify the identifier of the pool when it differs from the ProtocolComponent.id. For example, Balancer pools have a component ID that corresponds to their contract address, and a separate pool ID used for registration on the Balancer Vault contract (needed for swaps and simulations).

Notice: In most of the cases, using ProtocolComponent.id is preferred over pool_id and pool_id should only be used if a special identifier is strictly necessary.

Type

This attribute value must be provided as a UTF-8 encoded string in bytes.

Example Usage

Attribute {
    name: "pool_id".to_string(),
    value: format!("0x{}", hex::encode(pool_registered.pool_id)).as_bytes(),
    change: ChangeType::Creation.into(),
}

State Attributes

The following attributes names are reserved and must be given using EntityChanges. Unlike static attributes, state attributes are updatable.

1. stateless_contract_addr

Description

The stateless_contract_addr_{index} field specifies the address of a stateless contract required by the component. Stateless contracts are those where storage is not accessed for the calls made to it during swaps or simulations.

This is particularly useful in scenarios involving DELEGATECALL. If the contract's bytecode can be retrieved in Substreams, provide it using the stateless_contract_code attribute (see below).

Note: If no contract code is given, the consumer of the indexed protocol has to access a chain node to fetch the code. This is considered non-ideal and should be avoided where possible.

An index is used if multiple stateless contracts are needed. This index should start at 0 and increment by 1 for each additional stateless_contract_addr.

The value for stateless_contract_addr_{index} can be provided in two ways:

1. Direct Contract Address: A static contract address can be specified directly.

2. Dynamic Address Resolution: Alternatively, you can define a function or method that dynamically resolves and retrieves the stateless contract address at runtime. This can be particularly useful in complex contract architectures, such as those using a dynamic proxy pattern. It is important to note that the called contract must be indexed by the Substreams module.

Type

This attribute value must be provided as a UTF-8 encoded string in bytes.

Example Usage

1. Direct Contract Address

To specify a direct contract address:

Attribute {
    name: "stateless_contract_addr_0".into(),
    value: format!("0x{}", hex::encode(address)).into_bytes(),
    change: ChangeType::Creation.into(),
}
Attribute {
    name: "stateless_contract_addr_1".into(),
    value: format!("0x{}", hex::encode(other_address)).into_bytes(),
    change: ChangeType::Creation.into(),
}

2. Dynamic Address Resolution

To specify a function that dynamically resolves the address:

Attribute {
    name: "stateless_contract_addr_0".into(),
    // Call views_implementation() on TRICRYPTO_FACTORY
    value: format!("call:0x{}:views_implementation()", hex::encode(TRICRYPTO_FACTORY)).into_bytes(),
    change: ChangeType::Creation.into(),
}

2. stateless_contract_code

Description

The stateless_contract_code_{index} field is used to specify the bytecode for a given stateless_contract_addr. The index used here must match with the index of the related address.

Type

This attribute value must be provided as bytes.

Example Usage

Attribute {
    name: "stateless_contract_code_0".to_string(),
    value: code.to_vec(),
    change: ChangeType::Creation.into(),
}

3. update_marker

Description

The update_marker field is used to indicate that a pool has changed, thereby triggering an update on the protocol component. This is particularly useful for when manual_updates is enabled.

Type

Set to [1u8]to trigger an update.

Example Usage

Attribute {
    name: "update_marker".to_string(),
    value: vec![1u8],
    change: ChangeType::Update.into(),
};

4. balance_owner[deprecated]

Description

The balance_owner field specifies the address of the account that owns the protocol component tokens, when tokens are not owned by the protocol component itself or the multiple contracts are involved. This is particularly useful for protocols that use a vault, for example Balancer.

The use of the balance_owner reserved attribute has been deprecated in favour of tracking contract balances directly. See Tracking Contract Balances.

Type

This attribute value must be provided as bytes.

Example Usage

Attribute {
    name: "balance_owner".to_string(),
    value: VAULT_ADDRESS.to_vec(),
    change: ChangeType::Creation.into(),
}