Error generates a response with StatusError and uses err as message.

Errors generates a response with StatusError and the given message.

IsStatusError is used to determine if the given status is error.

JSON is used to assist in generating a response in which the body is in JSON format.

OK generates a response with StatusOK and the given body.

StatusError is used when contract fails.

StatusErrorThreshold is the status dividing line for the normal operation of the contract.

StatusOK is used when contract successfully ends.

Response is the result of the contract run.

GetContractState is the context in which the contract runs.

Contract is the interface of contract.

Driver 接口用于抽象执行合约的框架.