cosmos-sdk/x/gov/spec/02_state.md

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# State
## Parameters and base types
`Parameters` define the rules according to which votes are run. There can only
be one active parameter set at any given time. If governance wants to change a
parameter set, either to modify a value or add/remove a parameter field, a new
parameter set has to be created and the previous one rendered inactive.
```go
type DepositParams struct {
MinDeposit sdk.Coins // Minimum deposit for a proposal to enter voting period.
MaxDepositPeriod time.Time // Maximum period for Atom holders to deposit on a proposal. Initial value: 2 months
}
```
```go
type VotingParams struct {
VotingPeriod time.Time // Length of the voting period. Initial value: 2 weeks
}
```
```go
type TallyParams struct {
Quorum sdk.Dec // Minimum percentage of stake that needs to vote for a proposal to be considered valid
Threshold sdk.Dec // Minimum proportion of Yes votes for proposal to pass. Initial value: 0.5
Veto sdk.Dec // Minimum proportion of Veto votes to Total votes ratio for proposal to be vetoed. Initial value: 1/3
}
```
Parameters are stored in a global `GlobalParams` KVStore.
Additionally, we introduce some basic types:
```go
type Vote byte
const (
VoteYes = 0x1
VoteNo = 0x2
VoteNoWithVeto = 0x3
VoteAbstain = 0x4
)
type ProposalType string
const (
ProposalTypePlainText = "Text"
ProposalTypeSoftwareUpgrade = "SoftwareUpgrade"
)
type ProposalStatus byte
const (
StatusNil ProposalStatus = 0x00
StatusDepositPeriod ProposalStatus = 0x01 // Proposal is submitted. Participants can deposit on it but not vote
StatusVotingPeriod ProposalStatus = 0x02 // MinDeposit is reached, participants can vote
StatusPassed ProposalStatus = 0x03 // Proposal passed and successfully executed
StatusRejected ProposalStatus = 0x04 // Proposal has been rejected
StatusFailed ProposalStatus = 0x05 // Proposal passed but failed execution
)
```
## Deposit
```go
type Deposit struct {
Amount sdk.Coins // Amount of coins deposited by depositor
Depositor crypto.address // Address of depositor
}
```
## ValidatorGovInfo
This type is used in a temp map when tallying
```go
type ValidatorGovInfo struct {
Minus sdk.Dec
Vote Vote
}
```
## Proposals
`Proposal` objects are used to account votes and generally track the proposal's state. They contain `Content` which denotes
what this proposal is about, and other fields, which are the mutable state of
the governance process.
```go
type Proposal struct {
Content // Proposal content interface
ProposalID uint64
Status ProposalStatus // Status of the Proposal {Pending, Active, Passed, Rejected}
FinalTallyResult TallyResult // Result of Tallies
SubmitTime time.Time // Time of the block where TxGovSubmitProposal was included
DepositEndTime time.Time // Time that the Proposal would expire if deposit amount isn't met
TotalDeposit sdk.Coins // Current deposit on this proposal. Initial value is set at InitialDeposit
VotingStartTime time.Time // Time of the block where MinDeposit was reached. -1 if MinDeposit is not reached
VotingEndTime time.Time // Time that the VotingPeriod for this proposal will end and votes will be tallied
}
```
```go
type Content interface {
GetTitle() string
GetDescription() string
ProposalRoute() string
ProposalType() string
ValidateBasic() sdk.Error
String() string
}
```
The `Content` on a proposal is an interface which contains the information about
the `Proposal` such as the tile, description, and any notable changes. Also, this
`Content` type can by implemented by any module. The `Content`'s `ProposalRoute`
returns a string which must be used to route the `Content`'s `Handler` in the
governance keeper. This allows the governance keeper to execute proposal logic
implemented by any module. If a proposal passes, the handler is executed. Only
if the handler is successful does the state get persisted and the proposal finally
passes. Otherwise, the proposal is rejected.
```go
type Handler func(ctx sdk.Context, content Content) sdk.Error
```
The `Handler` is responsible for actually executing the proposal and processing
any state changes specified by the proposal. It is executed only if a proposal
passes during `EndBlock`.
We also mention a method to update the tally for a given proposal:
```go
func (proposal Proposal) updateTally(vote byte, amount sdk.Dec)
```
## Stores
_Stores are KVStores in the multi-store. The key to find the store is the first
parameter in the list_`
We will use one KVStore `Governance` to store two mappings:
- A mapping from `proposalID|'proposal'` to `Proposal`.
- A mapping from `proposalID|'addresses'|address` to `Vote`. This mapping allows
us to query all addresses that voted on the proposal along with their vote by
doing a range query on `proposalID:addresses`.
For pseudocode purposes, here are the two function we will use to read or write in stores:
- `load(StoreKey, Key)`: Retrieve item stored at key `Key` in store found at key `StoreKey` in the multistore
- `store(StoreKey, Key, value)`: Write value `Value` at key `Key` in store found at key `StoreKey` in the multistore
## Proposal Processing Queue
**Store:**
- `ProposalProcessingQueue`: A queue `queue[proposalID]` containing all the
`ProposalIDs` of proposals that reached `MinDeposit`. During each `EndBlock`,
all the proposals that have reached the end of their voting period are processed.
To process a finished proposal, the application tallies the votes, computes the
votes of each validator and checks if every validator in the validator set has
voted. If the proposal is accepted, deposits are refunded. Finally, the proposal
content `Handler` is executed.
And the pseudocode for the `ProposalProcessingQueue`:
```go
in EndBlock do
for finishedProposalID in GetAllFinishedProposalIDs(block.Time)
proposal = load(Governance, <proposalID|'proposal'>) // proposal is a const key
validators = Keeper.getAllValidators()
tmpValMap := map(sdk.AccAddress)ValidatorGovInfo
// Initiate mapping at 0. This is the amount of shares of the validator's vote that will be overridden by their delegator's votes
for each validator in validators
tmpValMap(validator.OperatorAddr).Minus = 0
// Tally
voterIterator = rangeQuery(Governance, <proposalID|'addresses'>) //return all the addresses that voted on the proposal
for each (voterAddress, vote) in voterIterator
delegations = stakingKeeper.getDelegations(voterAddress) // get all delegations for current voter
for each delegation in delegations
// make sure delegation.Shares does NOT include shares being unbonded
tmpValMap(delegation.ValidatorAddr).Minus += delegation.Shares
proposal.updateTally(vote, delegation.Shares)
_, isVal = stakingKeeper.getValidator(voterAddress)
if (isVal)
tmpValMap(voterAddress).Vote = vote
tallyingParam = load(GlobalParams, 'TallyingParam')
// Update tally if validator voted they voted
for each validator in validators
if tmpValMap(validator).HasVoted
proposal.updateTally(tmpValMap(validator).Vote, (validator.TotalShares - tmpValMap(validator).Minus))
// Check if proposal is accepted or rejected
totalNonAbstain := proposal.YesVotes + proposal.NoVotes + proposal.NoWithVetoVotes
if (proposal.Votes.YesVotes/totalNonAbstain > tallyingParam.Threshold AND proposal.Votes.NoWithVetoVotes/totalNonAbstain < tallyingParam.Veto)
// proposal was accepted at the end of the voting period
// refund deposits (non-voters already punished)
for each (amount, depositor) in proposal.Deposits
depositor.AtomBalance += amount
stateWriter, err := proposal.Handler()
if err != nil
// proposal passed but failed during state execution
proposal.CurrentStatus = ProposalStatusFailed
else
// proposal pass and state is persisted
proposal.CurrentStatus = ProposalStatusAccepted
stateWriter.save()
else
// proposal was rejected
proposal.CurrentStatus = ProposalStatusRejected
store(Governance, <proposalID|'proposal'>, proposal)
```