State

State Objects

The x/epochs module keeps the following objects in state:

State Object	Description	Key	Value	Store
EpochInfo	Epoch info bytecode	[]byte{identifier}	[]byte{epochInfo}	KV

EpochInfo

An EpochInfo defines several variables:

1. identifier keeps an epoch identification string

2. start_time keeps the start time for epoch counting: if block height passes start_time, then epoch_counting_started is set

3. duration keeps the target epoch duration

4. current_epoch keeps the current active epoch number

5. current_epoch_start_time keeps the start time of the current epoch

6. epoch_counting_started is a flag set with start_time, at which point epoch_number will be counted

7. current_epoch_start_height keeps the start block height of the current epoch

message EpochInfo {
    string identifier = 1;
    google.protobuf.Timestamp start_time = 2 [
        (gogoproto.stdtime) = true,
        (gogoproto.nullable) = false,
        (gogoproto.moretags) = "yaml:\"start_time\""
    ];
    google.protobuf.Duration duration = 3 [
        (gogoproto.nullable) = false,
        (gogoproto.stdduration) = true,
        (gogoproto.jsontag) = "duration,omitempty",
        (gogoproto.moretags) = "yaml:\"duration\""
    ];
    int64 current_epoch = 4;
    google.protobuf.Timestamp current_epoch_start_time = 5 [
        (gogoproto.stdtime) = true,
        (gogoproto.nullable) = false,
        (gogoproto.moretags) = "yaml:\"current_epoch_start_time\""
    ];
    bool epoch_counting_started = 6;
    reserved 7;
    int64 current_epoch_start_height = 8;
}

The epochs module keeps these EpochInfo objects in state, which are initialized at genesis and are modified on begin blockers or end blockers.

Genesis State

The x/epochs module's GenesisState defines the state necessary for initializing the chain from a previously exported height. It contains a slice containing all the EpochInfo objects kept in state:

// Genesis State defines the epoch module's genesis state
type GenesisState struct {
    // list of EpochInfo structs corresponding to all epochs
	Epochs []EpochInfo `protobuf:"bytes,1,rep,name=epochs,proto3" json:"epochs"`
}