cosmos-sdk/examples/democoin/x/oracle/handler.go

107 lines
2.6 KiB
Go

package oracle
import (
"bytes"
sdk "github.com/cosmos/cosmos-sdk/types"
)
// Handler handles payload after it passes voting process
type Handler func(ctx sdk.Context, p Payload) sdk.Error
func (keeper Keeper) update(ctx sdk.Context, val sdk.Validator, valset sdk.ValidatorSet, p Payload, info Info) Info {
info.Power = info.Power.Add(val.GetPower())
// Return if the voted power is not bigger than required power
totalPower := valset.TotalPower(ctx)
requiredPower := totalPower.Mul(keeper.supermaj)
if !info.Power.GT(requiredPower) {
return info
}
// Check if the validators hash has been changed during the vote process
// and recalculate voted power
hash := ctx.BlockHeader().ValidatorsHash
if !bytes.Equal(hash, info.Hash) {
info.Power = sdk.ZeroDec()
info.Hash = hash
prefix := GetSignPrefix(p, keeper.cdc)
store := ctx.KVStore(keeper.key)
iter := sdk.KVStorePrefixIterator(store, prefix)
defer iter.Close()
for ; iter.Valid(); iter.Next() {
if valset.Validator(ctx, iter.Value()) != nil {
store.Delete(iter.Key())
continue
}
info.Power = info.Power.Add(val.GetPower())
}
if !info.Power.GT(totalPower.Mul(keeper.supermaj)) {
return info
}
}
info.Status = Processed
return info
}
// Handle is used by other modules to handle Msg
func (keeper Keeper) Handle(h Handler, ctx sdk.Context, o Msg, codespace sdk.CodespaceType) sdk.Result {
valset := keeper.valset
signer := o.Signer
payload := o.Payload
// Check the oracle is not in process
info := keeper.Info(ctx, payload)
if info.Status != Pending {
return ErrAlreadyProcessed(codespace).Result()
}
// Check if it is reporting timeout
now := ctx.BlockHeight()
if now > info.LastSigned+keeper.timeout {
info = Info{Status: Timeout}
keeper.setInfo(ctx, payload, info)
keeper.clearSigns(ctx, payload)
return sdk.Result{}
}
info.LastSigned = ctx.BlockHeight()
// check the signer is a validator
val := valset.Validator(ctx, sdk.ValAddress(signer))
if val == nil {
return ErrNotValidator(codespace, signer).Result()
}
// Check double signing
if keeper.signed(ctx, payload, signer) {
return ErrAlreadySigned(codespace).Result()
}
keeper.sign(ctx, payload, signer)
info = keeper.update(ctx, val, valset, payload, info)
if info.Status == Processed {
info = Info{Status: Processed}
}
keeper.setInfo(ctx, payload, info)
if info.Status == Processed {
keeper.clearSigns(ctx, payload)
cctx, write := ctx.CacheContext()
err := h(cctx, payload)
if err != nil {
return sdk.Result{
Code: sdk.ABCICodeOK,
Log: err.ABCILog(),
}
}
write()
}
return sdk.Result{}
}