synapsecns/sanguine

package db

import (
    "context"
    "time"

    "gorm.io/gorm"
)

// ChainListenerDB is the interface for the chain listener database.
type ChainListenerDB interface {
    // PutLatestBlock upserts the latest block on a given chain id to be new height.
    PutLatestBlock(ctx context.Context, chainID, height uint64) error
    // LatestBlockForChain gets the latest block for a given chain id.
    // will return ErrNoLatestBlockForChainID if no block exists for the chain.
    LatestBlockForChain(ctx context.Context, chainID uint64) (uint64, error)
    // SetListenerName sets the listener name.
    SetListenerName(name string)
}

// LastIndexed is used to make sure we haven't missed any events while offline.
// since we event source - rather than use a state machine this is needed to make sure we haven't missed any events
// by allowing us to go back and source any events we may have missed.
//
// this does not inherit from gorm.model to allow us to use ChainID as a primary key.
type LastIndexed struct {
    // CreatedAt is the creation time
    CreatedAt time.Time
    // UpdatedAt is the update time
    UpdatedAt time.Time
    // DeletedAt time
    DeletedAt gorm.DeletedAt `gorm:"index"`
    // ChainID is the chain id of the chain we're watching blocks on. This is our primary index.
    ChainID uint64 `gorm:"column:chain_id;index:idx_chain_name,unique"`
    // BlockHeight is the highest height we've seen on the chain
    BlockNumber int `gorm:"block_number"`
    // ListenerName is the name of the listener that is tracking this chain
    ListenerName string `gorm:"column:listener_name;index:idx_chain_name,unique"`
}

// GetAllModels gets all models to migrate
// see: https://medium.com/@SaifAbid/slice-interfaces-8c78f8b6345d for an explanation of why we can't do this at initialization time
func GetAllModels() (allModels []interface{}) {
    allModels = []interface{}{&LastIndexed{}}
    return allModels
}