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Hook Extension APIs

GenesisHook​

// GenesisHook is a function that is run exactly once, at network genesis.
// It can be used to create initial state or perform other setup tasks.
// If it returns an error, the network will immediately halt. Any state
// changed or error returned should be deterministic, as all nodes will
// run the same GenesisHooks in the same order.
type GenesisHook func(ctx context.Context, app *common.App, chain *common.ChainContext) error

EndBlockHook​

// EndBlockHook is a function that is run at the end of each block, after
// all of the transactions in the block have been processed, but before the
// any state has been committed. It is meant to be used to alter state, send
// data to external services, or perform cleanup tasks for other extensions.
// An error returned will halt the local node. All state changes and errors
// should be deterministic, as all nodes will run the same EndBlockHooks in
// the same order.
type EndBlockHook func(ctx context.Context, app *common.App, block *common.BlockContext) error