0g-chain/x/committee/keeper/proposal.go
2020-04-27 19:19:05 +01:00

180 lines
6.1 KiB
Go

package keeper
import (
"fmt"
sdk "github.com/cosmos/cosmos-sdk/types"
sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
"github.com/kava-labs/kava/x/committee/types"
)
// SubmitProposal adds a proposal to a committee so that it can be voted on.
func (k Keeper) SubmitProposal(ctx sdk.Context, proposer sdk.AccAddress, committeeID uint64, pubProposal types.PubProposal) (uint64, error) {
// Limit proposals to only be submitted by committee members
com, found := k.GetCommittee(ctx, committeeID)
if !found {
return 0, sdkerrors.Wrapf(types.ErrUnknownCommittee, "%d", committeeID)
}
if !com.HasMember(proposer) {
return 0, sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "proposer not member of committee")
}
// Check committee has permissions to enact proposal.
if !com.HasPermissionsFor(pubProposal) {
return 0, sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "committee does not have permissions to enact proposal")
}
// Check proposal is valid
if err := k.ValidatePubProposal(ctx, pubProposal); err != nil {
return 0, err
}
// Get a new ID and store the proposal
deadline := ctx.BlockTime().Add(com.ProposalDuration)
proposalID, err := k.StoreNewProposal(ctx, pubProposal, committeeID, deadline)
if err != nil {
return 0, err
}
ctx.EventManager().EmitEvent(
sdk.NewEvent(
types.EventTypeProposalSubmit,
sdk.NewAttribute(types.AttributeKeyCommitteeID, fmt.Sprintf("%d", com.ID)),
sdk.NewAttribute(types.AttributeKeyProposalID, fmt.Sprintf("%d", proposalID)),
),
)
return proposalID, nil
}
// AddVote submits a vote on a proposal.
func (k Keeper) AddVote(ctx sdk.Context, proposalID uint64, voter sdk.AccAddress) error {
// Validate
pr, found := k.GetProposal(ctx, proposalID)
if !found {
return sdkerrors.Wrapf(types.ErrUnknownProposal, "%d", proposalID)
}
if pr.HasExpiredBy(ctx.BlockTime()) {
return sdkerrors.Wrapf(types.ErrProposalExpired, "%s ≥ %s", ctx.BlockTime(), pr.Deadline)
}
com, found := k.GetCommittee(ctx, pr.CommitteeID)
if !found {
return sdkerrors.Wrapf(types.ErrUnknownCommittee, "%d", pr.CommitteeID)
}
if !com.HasMember(voter) {
return sdkerrors.Wrap(sdkerrors.ErrUnauthorized, "voter must be a member of committee")
}
// Store vote, overwriting any prior vote
k.SetVote(ctx, types.Vote{ProposalID: proposalID, Voter: voter})
ctx.EventManager().EmitEvent(
sdk.NewEvent(
types.EventTypeProposalVote,
sdk.NewAttribute(types.AttributeKeyCommitteeID, fmt.Sprintf("%d", com.ID)),
sdk.NewAttribute(types.AttributeKeyProposalID, fmt.Sprintf("%d", pr.ID)),
),
)
return nil
}
// GetProposalResult calculates if a proposal currently has enough votes to pass.
func (k Keeper) GetProposalResult(ctx sdk.Context, proposalID uint64) (bool, error) {
pr, found := k.GetProposal(ctx, proposalID)
if !found {
return false, sdkerrors.Wrapf(types.ErrUnknownProposal, "%d", proposalID)
}
com, found := k.GetCommittee(ctx, pr.CommitteeID)
if !found {
return false, sdkerrors.Wrapf(types.ErrUnknownCommittee, "%d", pr.CommitteeID)
}
numVotes := k.TallyVotes(ctx, proposalID)
proposalResult := sdk.NewDec(numVotes).GTE(com.VoteThreshold.MulInt64(int64(len(com.Members))))
return proposalResult, nil
}
// TallyVotes counts all the votes on a proposal
func (k Keeper) TallyVotes(ctx sdk.Context, proposalID uint64) int64 {
votes := k.GetVotesByProposal(ctx, proposalID)
return int64(len(votes))
}
// EnactProposal makes the changes proposed in a proposal.
func (k Keeper) EnactProposal(ctx sdk.Context, proposalID uint64) error {
pr, found := k.GetProposal(ctx, proposalID)
if !found {
return sdkerrors.Wrapf(types.ErrUnknownProposal, "%d", proposalID)
}
if err := k.ValidatePubProposal(ctx, pr.PubProposal); err != nil {
return err
}
handler := k.router.GetRoute(pr.ProposalRoute())
if err := handler(ctx, pr.PubProposal); err != nil {
// the handler should not error as it was checked in ValidatePubProposal
panic(fmt.Sprintf("unexpected handler error: %s", err))
}
return nil
}
// CloseExpiredProposals removes proposals (and associated votes) that have past their deadline.
func (k Keeper) CloseExpiredProposals(ctx sdk.Context) {
k.IterateProposals(ctx, func(proposal types.Proposal) bool {
if !proposal.HasExpiredBy(ctx.BlockTime()) {
return false
}
k.DeleteProposalAndVotes(ctx, proposal.ID)
ctx.EventManager().EmitEvent(
sdk.NewEvent(
types.EventTypeProposalClose,
sdk.NewAttribute(types.AttributeKeyCommitteeID, fmt.Sprintf("%d", proposal.CommitteeID)),
sdk.NewAttribute(types.AttributeKeyProposalID, fmt.Sprintf("%d", proposal.ID)),
sdk.NewAttribute(types.AttributeKeyProposalCloseStatus, types.AttributeValueProposalTimeout),
),
)
return false
})
}
// ValidatePubProposal checks if a pubproposal is valid.
func (k Keeper) ValidatePubProposal(ctx sdk.Context, pubProposal types.PubProposal) (returnErr error) {
if pubProposal == nil {
return sdkerrors.Wrap(types.ErrInvalidPubProposal, "pub proposal cannot be nil")
}
if err := pubProposal.ValidateBasic(); err != nil {
return err
}
if !k.router.HasRoute(pubProposal.ProposalRoute()) {
return sdkerrors.Wrapf(types.ErrNoProposalHandlerExists, "%T", pubProposal)
}
// Run the proposal's changes through the associated handler using a cached version of state to ensure changes are not permanent.
cacheCtx, _ := ctx.CacheContext()
handler := k.router.GetRoute(pubProposal.ProposalRoute())
// Handle an edge case where a param change proposal causes the proposal handler to panic.
// A param change proposal with a registered subspace value but unregistered key value will cause a panic in the param change proposal handler.
// This defer will catch panics and return a normal error: `recover()` gets the panic value, then the enclosing function's return value is swapped for an error.
// reference: https://stackoverflow.com/questions/33167282/how-to-return-a-value-in-a-go-function-that-panics?noredirect=1&lq=1
defer func() {
if r := recover(); r != nil {
returnErr = sdkerrors.Wrapf(types.ErrInvalidPubProposal, "proposal handler panicked: %s", r)
}
}()
if err := handler(cacheCtx, pubProposal); err != nil {
return err
}
return nil
}