ChainBridge¶

Calls¶

acknowledge_proposal¶

Commits a vote in favour of the provided proposal.

If a proposal with the given nonce and source chain ID does not already exist, it will be created with an initial vote in favour from the caller.

# <weight> - weight of proposed call, regardless of whether execution is performed # </weight>

Attributes¶

Name	Type
nonce	`DepositNonce`
src_id	`ChainId`
r_id	`ResourceId`
call	`Box<<T as Config>::Proposal>`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'acknowledge_proposal', {
    'call': 'Call',
    'nonce': 'u64',
    'r_id': '[u8; 32]',
    'src_id': 'u8',
}
)

add_relayer¶

Adds a new relayer to the relayer set.

# <weight> - O(1) lookup and insert # </weight>

Attributes¶

Name	Type
v	`T::AccountId`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'add_relayer', {'v': 'AccountId'}
)

eval_vote_state¶

Evaluate the state of a proposal given the current vote threshold.

A proposal with enough votes will be either executed or cancelled, and the status will be updated accordingly.

# <weight> - weight of proposed call, regardless of whether execution is performed # </weight>

Attributes¶

Name	Type
nonce	`DepositNonce`
src_id	`ChainId`
proposal	`Box<<T as Config>::Proposal>`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'eval_vote_state', {
    'nonce': 'u64',
    'proposal': 'Call',
    'src_id': 'u8',
}
)

reject_proposal¶

Commits a vote against a provided proposal.

# <weight> - Fixed, since execution of proposal should not be included # </weight>

Attributes¶

Name	Type
nonce	`DepositNonce`
src_id	`ChainId`
r_id	`ResourceId`
call	`Box<<T as Config>::Proposal>`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'reject_proposal', {
    'call': 'Call',
    'nonce': 'u64',
    'r_id': '[u8; 32]',
    'src_id': 'u8',
}
)

remove_relayer¶

Removes an existing relayer from the set.

# <weight> - O(1) lookup and removal # </weight>

Attributes¶

Name	Type
account_id	`T::AccountId`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'remove_relayer', {'account_id': 'AccountId'}
)

remove_resource¶

Removes a resource ID from the resource mapping.

After this call, bridge transfers with the associated resource ID will be rejected.

# <weight> - O(1) removal # </weight>

Attributes¶

Name	Type
id	`ResourceId`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'remove_resource', {'id': '[u8; 32]'}
)

set_resource¶

Stores a method name on chain under an associated resource ID.

# <weight> - O(1) write # </weight>

Attributes¶

Name	Type
id	`ResourceId`
method	`Vec<u8>`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'set_resource', {'id': '[u8; 32]', 'method': 'Bytes'}
)

set_threshold¶

Sets the vote threshold for proposals.

This threshold is used to determine how many votes are required before a proposal is executed.

# <weight> - O(1) lookup and insert # </weight>

Attributes¶

Name	Type
threshold	`u32`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'set_threshold', {'threshold': 'u32'}
)

whitelist_chain¶

Enables a chain ID as a source or destination for a bridge transfer.

# <weight> - O(1) lookup and insert # </weight>

Attributes¶

Name	Type
id	`ChainId`

Python¶

call = substrate.compose_call(
    'ChainBridge', 'whitelist_chain', {'id': 'u8'}
)

Events¶

ChainWhitelisted¶

Chain now available for transfers (chain_id)

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`

FungibleTransfer¶

FunglibleTransfer is for relaying fungibles (dest_id, nonce, resource_id, amount, recipient, metadata)

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`
None	`ResourceId`	`[u8; 32]`
None	`U256`	`scale_info::131`
None	`Vec<u8>`	`Bytes`

GenericTransfer¶

GenericTransfer is for a generic data payload (dest_id, nonce, resource_id, metadata)

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`
None	`ResourceId`	`[u8; 32]`
None	`Vec<u8>`	`Bytes`

NonFungibleTransfer¶

NonFungibleTransfer is for relaying NFTS (dest_id, nonce, resource_id, token_id, recipient, metadata)

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`
None	`ResourceId`	`[u8; 32]`
None	`Vec<u8>`	`Bytes`
None	`Vec<u8>`	`Bytes`
None	`Vec<u8>`	`Bytes`

ProposalApproved¶

Voting successful for a proposal

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`

ProposalFailed¶

Execution of call failed

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`

ProposalRejected¶

Voting rejected a proposal

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`

ProposalSucceeded¶

Execution of call succeeded

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`

RelayerAdded¶

Relayer added to set

Attributes¶

Name	Type	Composition
None	`T::AccountId`	`AccountId`

RelayerRemoved¶

Relayer removed from set

Attributes¶

Name	Type	Composition
None	`T::AccountId`	`AccountId`

RelayerThresholdChanged¶

Vote threshold has changed (new_threshold)

Attributes¶

Name	Type	Composition
None	`u32`	`u32`

VoteAgainst¶

Vot submitted against proposal

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`
None	`T::AccountId`	`AccountId`

VoteFor¶

Vote submitted in favour of proposal

Attributes¶

Name	Type	Composition
None	`ChainId`	`u8`
None	`DepositNonce`	`u64`
None	`T::AccountId`	`AccountId`

Storage functions¶

ChainNonces¶

All whitelisted chains and their respective transaction counts

Python¶

result = substrate.query(
    'ChainBridge', 'ChainNonces', ['u8']
)

Return value¶

'u64'

RelayerCount¶

Number of relayers in set

Python¶

result = substrate.query(
    'ChainBridge', 'RelayerCount', []
)

Return value¶

'u32'

RelayerVoteThreshold¶

Number of votes required for a proposal to execute

Python¶

result = substrate.query(
    'ChainBridge', 'RelayerVoteThreshold', []
)

Return value¶

'u32'

Relayers¶

Tracks current relayer set

Python¶

result = substrate.query(
    'ChainBridge', 'Relayers', ['AccountId']
)

Return value¶

'bool'

Resources¶

Utilized by the bridge software to map resource IDs to actual methods

Python¶

result = substrate.query(
    'ChainBridge', 'Resources', ['[u8; 32]']
)

Return value¶

'Bytes'

Votes¶

All known proposals. The key is the hash of the call and the deposit ID, to ensure it's unique.

Python¶

result = substrate.query(
    'ChainBridge', 'Votes', ['u8', ('u64', 'Call')]
)

Return value¶

{
    'expiry': 'u32',
    'status': ('Initiated', 'Approved', 'Rejected'),
    'votes_against': ['AccountId'],
    'votes_for': ['AccountId'],
}

Constants¶

ChainId¶

The identifier for this chain. This must be unique and must not collide with existing IDs within a set of bridged chains.

Value¶

Python¶

constant = substrate.get_constant('ChainBridge', 'ChainId')

PalletId¶

Constant configuration parameter to store the module identifier for the pallet.

The module identifier may be of the form PalletId(*b"chnbrdge") and set using the parameter_types

Value¶

'0x63686e6272646765'

Python¶

constant = substrate.get_constant('ChainBridge', 'PalletId')

ProposalLifetime¶

Value¶

Python¶

constant = substrate.get_constant('ChainBridge', 'ProposalLifetime')

RelayerVoteThreshold¶

Type for setting initial number of votes required for a proposal to be executed (see [RelayerVoteThreshold] in storage section).

Value¶

Python¶

constant = substrate.get_constant('ChainBridge', 'RelayerVoteThreshold')

Errors¶

ChainAlreadyWhitelisted¶

Chain has already been enabled

ChainNotWhitelisted¶

Interactions with this chain is not permitted

InvalidChainId¶

Provided chain Id is not valid

InvalidThreshold¶

Relayer threshold cannot be 0

MustBeRelayer¶

Protected operation, must be performed by relayer

ProposalAlreadyComplete¶

Proposal has either failed or succeeded

ProposalAlreadyExists¶

A proposal with these parameters has already been submitted

ProposalDoesNotExist¶

No proposal with the ID was found

ProposalExpired¶

Lifetime of proposal has been exceeded

ProposalNotComplete¶

Cannot complete proposal, needs more votes

RelayerAlreadyExists¶

Relayer already in set

RelayerAlreadyVoted¶

Relayer has already submitted some vote for this proposal

RelayerInvalid¶

Provided accountId is not a relayer

ResourceDoesNotExist¶

Resource ID provided isn't mapped to anything

ThresholdNotSet¶

Relayer threshold not set