cosmos-sdk/x/staking/spec/03_messages.md

6.2 KiB

Messages

In this section we describe the processing of the staking messages and the corresponding updates to the state. All created/modified state objects specified by each message are defined within the state section.

MsgCreateValidator

A validator is created using the MsgCreateValidator message.

type MsgCreateValidator struct {
    Description    Description
    Commission     Commission

    DelegatorAddr  sdk.AccAddress
    ValidatorAddr  sdk.ValAddress
    PubKey         crypto.PubKey
    Delegation     sdk.Coin
}

This message is expected to fail if:

  • another validator with this operator address is already registered
  • another validator with this pubkey is already registered
  • the initial self-delegation tokens are of a denom not specified as the bonding denom
  • the commission parameters are faulty, namely:
    • MaxRate is either > 1 or < 0
    • the initial Rate is either negative or > MaxRate
    • the initial MaxChangeRate is either negative or > MaxRate
  • the description fields are too large

This message creates and stores the Validator object at appropriate indexes. Additionally a self-delegation is made with the initial tokens delegation tokens Delegation. The validator always starts as unbonded but may be bonded in the first end-block.

MsgEditValidator

The Description, CommissionRate of a validator can be updated using the MsgEditCandidacy.

type MsgEditCandidacy struct {
    Description     Description
    ValidatorAddr   sdk.ValAddress
    CommissionRate  sdk.Dec
}

This message is expected to fail if:

  • the initial CommissionRate is either negative or > MaxRate
  • the CommissionRate has already been updated within the previous 24 hours
  • the CommissionRate is > MaxChangeRate
  • the description fields are too large

This message stores the updated Validator object.

MsgDelegate

Within this message the delegator provides coins, and in return receives some amount of their validator's (newly created) delegator-shares that are assigned to Delegation.Shares.

type MsgDelegate struct {
  DelegatorAddr sdk.AccAddress
  ValidatorAddr sdk.ValAddress
  Amount        sdk.Coin
}

This message is expected to fail if:

  • the validator is does not exist
  • the validator is jailed
  • the Amount Coin has a denomination different than one defined by params.BondDenom

If an existing Delegation object for provided addresses does not already exist than it is created as part of this message otherwise the existing Delegation is updated to include the newly received shares.

MsgBeginUnbonding

The begin unbonding message allows delegators to undelegate their tokens from validator.

type MsgBeginUnbonding struct {
  DelegatorAddr sdk.AccAddress
  ValidatorAddr sdk.ValAddress
  Amount         sdk.Coin
}

This message is expected to fail if:

  • the delegation doesn't exist
  • the validator doesn't exist
  • the delegation has less shares than the ones worth of Amount
  • existing UnbondingDelegation has maximum entries as defined by params.MaxEntries
  • the Amount has a denomination different than one defined by params.BondDenom

When this message is processed the following actions occur:

  • validator's DelegatorShares and the delegation's Shares are both reduced by the message SharesAmount
  • calculate the token worth of the shares remove that amount tokens held within the validator
  • with those removed tokens, if the validator is:
    • Bonded - add them to an entry in UnbondingDelegation (create UnbondingDelegation if it doesn't exist) with a completion time a full unbonding period from the current time. Update pool shares to reduce BondedTokens and increase NotBondedTokens by token worth of the shares.
    • Unbonding - add them to an entry in UnbondingDelegation (create UnbondingDelegation if it doesn't exist) with the same completion time as the validator (UnbondingMinTime).
    • Unbonded - then send the coins the message DelegatorAddr
  • if there are no more Shares in the delegation, then the delegation object is removed from the store
    • under this situation if the delegation is the validator's self-delegation then also jail the validator.

MsgBeginRedelegate

The redelegation command allows delegators to instantly switch validators. Once the unbonding period has passed, the redelegation is automatically completed in the EndBlocker.

type MsgBeginRedelegate struct {
  DelegatorAddr    sdk.AccAddress
  ValidatorSrcAddr sdk.ValAddress
  ValidatorDstAddr sdk.ValAddress
  Amount           sdk.Coin
}

This message is expected to fail if:

  • the delegation doesn't exist
  • the source or destination validators don't exist
  • the delegation has less shares than the ones worth of Amount
  • the source validator has a receiving redelegation which is not matured (aka. the redelegation may be transitive)
  • existing Redelegation has maximum entries as defined by params.MaxEntries
  • the Amount Coin has a denomination different than one defined by params.BondDenom

When this message is processed the following actions occur:

  • the source validator's DelegatorShares and the delegations Shares are both reduced by the message SharesAmount
  • calculate the token worth of the shares remove that amount tokens held within the source validator.
  • if the source validator is:
    • Bonded - add an entry to the Redelegation (create Redelegation if it doesn't exist) with a completion time a full unbonding period from the current time. Update pool shares to reduce BondedTokens and increase NotBondedTokens by token worth of the shares (this may be effectively reversed in the next step however).
    • Unbonding - add an entry to the Redelegation (create Redelegation if it doesn't exist) with the same completion time as the validator (UnbondingMinTime).
    • Unbonded - no action required in this step
  • Delegate the token worth to the destination validator, possibly moving tokens back to the bonded state.
  • if there are no more Shares in the source delegation, then the source delegation object is removed from the store
    • under this situation if the delegation is the validator's self-delegation then also jail the validator.