OptionalonMessage: ((msg: EventSourceMessage) => void)A function that will be called on each message.
OptionalonId: ((id: string) => void)A function that will be called on each id field.
OptionalonRetry: ((retry: number) => void)A function that will be called on each retry field.
A function that should be called for each incoming line buffer.
Optionalflush: boolean
Parses line buffers into EventSourceMessages.