CN107562513A - A kind of management method of the intelligent contract life cycle based on JAVA - Google Patents

Abstract

The invention discloses a JAVA-based smart contract life cycle management method. The method handles the client's deployment, calling, upgrading, freezing and unfreezing contract requests by implementing a JCEE server, and generates a unique contract for each contract. address and instantiate a contract object, which is used to process all requests sent to the corresponding contract address, the JCEE server will perform a security check on each contract request, check the legitimacy of its bytecode, and only after the check passes It will process the request of the contract and return the result to the client. Since this product is developed based on the JAVA language, users can deploy it to any blockchain platform for contract lifecycle management, which improves the scalability of the blockchain platform.

Description

A JAVA-based smart contract life cycle management method

technical field

The present invention relates to blockchain technology, in particular to a JAVA-based smart contract life cycle management method.

Background technique

Blockchain technology, blockchain is a new type of decentralized protocol that can safely store digital currency transactions or other data, information cannot be forged and tampered with, and transaction confirmation on the blockchain is shared by all nodes on the blockchain Completed, the consensus algorithm guarantees its consistency. A public ledger is maintained on the blockchain. The public ledger is visible to any node on the storage block, thus ensuring that it cannot be forged and tampered with.

A smart contract is an assembly language programmed on the blockchain. The term was proposed by Nick Szabo, an interdisciplinary legal scholar. His definition of a smart contract is "a smart contract is a set of commitments defined in digital form, including contract Participants can execute the agreement on these commitments.” In other words, a smart contract is a contract that can be automatically executed when certain conditions are met on a computer system. Often people don't write the bytecode themselves, but compile it from a higher level language, such as a specialized language like Solidity.

The decentralized and non-tamperable features of the blockchain provide a good development environment for smart contracts. Therefore, in recent years, a series of blockchain communities such as the Bitcoin network and the Ethereum network have begun to provide public smart contracts. Interface for contract programming. However, in the development process of smart contracts, there has been a lack of a complete life cycle management method, especially a smart contract management method based on the current mainstream programming language.

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention proposes a JAVA-based smart contract management method, which realizes the management of the entire smart contract life cycle from the management of smart contract deployment, calling, upgrading, freezing, and thawing. The specific technology The scheme is as follows:

A method for managing the life cycle of an intelligent contract based on JAVA, comprising the following steps:

Step 1: contract deployment;

The client of the JAVA based Contract Execution Engine (JCEE for short) receives the compressed class file input by the user, and then decompresses the class file and persists it to generate the unique contract address ContractAddress of the contract. Send a deployment request to the JCEE server together with the address of the class file; the JCEE server receives the contract deployment request from the JCEE client by listening to the specified port, first checks the security of the contract, and if the check passes, persists the contract to In the metadata database, the class file can then be loaded into the memory to deploy the contract; if the check fails, it will directly exit the contract deployment and return an error message to the JCEE client;

Step 2: Perform corresponding operations on the contract according to user needs:

(1) When the contract needs to be invoked: the JCEE client receives the invoke request input by the user, parses out the unique identifier of the invoked contract ContractAddress, the method name and parameters invoked by the contract, and sends the contract invoke request to the JCEE server; the JCEE server Receive the contract call request sent by the JCEE client by listening to the specified port, first perform a security check on the contract, if the check passes, call the specified method of the specified contract address and synchronize the ledger information to the JCEE client to realize the call of the contract, If the check fails, the contract call is terminated and an error message is returned to the JCEE client;

(2) When the contract needs to be upgraded: the JCEE client receives the upgrade update request input by the user, parses out the unique ContractAddress of the old contract, and sends the update request to the JCEE server together with the class file address of the new contract; the JCEE server monitors the specified The port receives the contract upgrade request sent by the JCEE client, and first performs a security check on the contract. If the check fails, it will directly exit this contract upgrade and return an error message to the JCEE client; if the check passes, proceed For the query of the old contract, if the old contract can be found, the old contract will be destroyed first, then the new contract will be persisted and the class file of the new contract will be loaded into the memory to complete the contract upgrade. If the old contract cannot be found, the new contract will be executed directly Persistence and loading of the contract to complete the upgrade of the contract;

(3) When the contract needs to be frozen: the JCEE client receives the freeze request input by the user, parses out the ContractAddress, the unique identifier of the contract to be frozen, and sends the freeze request to the JCEE server together with the new status bit of the contract; the JCEE server specifies through monitoring The port receives the contract freeze request sent by the JCEE client, and first checks the security of the contract. If the check is passed, the status bit of the contract is updated to the frozen state to realize the freezing of the contract; if the check fails, exit this time. The contract freezes and returns an error message to the JCEE client;

(4) When the contract needs to be unfrozen: the JCEE client receives the unfrozen unfrozen request input by the user, parses out the unique ContractAddress of the contract to be unfrozen, and sends the unfreeze request to the JCEE server together with the new status bit of the contract; the JCEE server monitors the specified The port receives the contract unfreezing request sent by the JCEE client, and first performs a security check on the contract. If the check is passed, the status bit of the contract is updated to the unfrozen state, and the contract is unfrozen; if the check fails, exit this time. Unfreeze the contract and return an error message to the JCEE client;

Furthermore, in step 1, the JCEE server uniformly manages all smart contracts, and each contract deployment is just a call to the JCEE server, instead of starting a single thread for each smart contract to maintain, which facilitates the entire platform The contract management also reduces the waste of system resources.

Further, in the step 1, the JCEE server communicates with the JCEE client through the remote procedure call protocol RPC, and the security check of the contract includes checking whether the contract bytecode is legal and checking whether the contract information contains the contract address .

Beneficial effects of the present invention: the present invention is applied to the blockchain platform, provides a set of brand-new smart contract life cycle management, and realizes the deployment, calling, upgrading, freezing, and thawing of the contract, and is a contract of the blockchain platform. Management provides convenience. At the same time, at each stage of the contract life cycle, this product will conduct security checks, which improves the security of the contract life cycle.

Description of drawings

Figure 1 is a state diagram of the deployment contract;

Figure 2 is an upgrade contract state diagram.

detailed description

The purpose and effect of the present invention will become more obvious by describing the present invention in detail according to the accompanying drawings and specific embodiments.

The present invention is a JAVA-based intelligent contract life cycle management method, comprising the following steps:

Step 1: contract deployment;

The client of JCEE, the smart contract execution engine based on the JAVA virtual machine, receives the compressed class file input by the user, then decompresses the class file and persists it, generates the unique contract address ContractAddress of the contract, and sends the address of the class file to the JCEE server Send a deployment request; the JCEE server receives the contract deployment request sent by the JCEE client by listening to the specified port, first checks the security of the contract, and if the check passes, the contract is persisted in the metadata database, and then the class can be Load the file into the memory for contract deployment; if the check fails, exit the contract deployment directly and return an error message to the JCEE client;

Step 2: Perform corresponding operations on the contract according to user needs:

(1) When the contract needs to be invoked: the JCEE client receives the invoke request input by the user, parses out the unique identifier of the invoked contract ContractAddress, the method name and parameters invoked by the contract, and sends the contract invoke request to the JCEE server; the JCEE server Receive the contract call request sent by the JCEE client by listening to the specified port, first perform a security check on the contract, if the check passes, call the specified method of the specified contract address and synchronize the ledger information to the JCEE client to realize the call of the contract, If the check fails, the contract call is terminated and an error message is returned to the JCEE client;

(2) When the contract needs to be upgraded: the JCEE client receives the upgrade update request input by the user, parses out the unique ContractAddress of the old contract, and sends the update request to the JCEE server together with the class file address of the new contract; the JCEE server monitors the specified The port receives the contract upgrade request sent by the JCEE client, and first performs a security check on the contract. If the check fails, it will directly exit this contract upgrade and return an error message to the JCEE client; if the check passes, proceed For the query of the old contract, if the old contract can be found, the old contract will be destroyed first, then the new contract will be persisted and the class file of the new contract will be loaded into the memory to complete the contract upgrade. If the old contract cannot be found, the new contract will be executed directly Persistence and loading of the contract to complete the upgrade of the contract;

(3) When the contract needs to be frozen: the JCEE client receives the freeze request input by the user, parses out the ContractAddress, the unique identifier of the contract to be frozen, and sends the freeze request to the JCEE server together with the new status bit of the contract; the JCEE server specifies through monitoring The port receives the contract freeze request sent by the JCEE client, and first checks the security of the contract. If the check is passed, the status bit of the contract is updated to the frozen state to realize the freezing of the contract; if the check fails, exit this time. The contract freezes and returns an error message to the JCEE client;

(4) When the contract needs to be unfrozen: the JCEE client receives the unfrozen unfrozen request input by the user, parses out the unique ContractAddress of the contract to be unfrozen, and sends the unfreeze request to the JCEE server together with the new status bit of the contract; the JCEE server monitors the specified The port receives the contract unfreezing request sent by the JCEE client, and first performs a security check on the contract. If the check is passed, the status bit of the contract is updated to the unfrozen state, and the contract is unfrozen; if the check fails, exit this time. The contract is unfrozen and an error message is returned to the JCEE client.

In step 1, the JCEE server uniformly manages all smart contracts, and each contract deployment is just a call to the JCEE server, instead of starting a single thread for each smart contract to maintain.

In step 1, the class file specified by the client also needs to provide some attribute information of the contract to facilitate the location of the class file for the JCEE client. After the JCEE client generates a unique contract address through the blockchain platform, To be able to send a contract deployment request to the JCEE server, the request needs to bring the contract address and contract-related information, such as the location of the contract file, etc. The JCEE server and the JCEE client can be set on the same host, or can be set On different hosts, the JCEE server communicates with the JCEE client through the remote procedure call protocol RPC. After obtaining the request from the JCEE client, it will check the security of the contract, check whether the contract bytecode is legal, etc. After the check is passed, The completeness of the contract will also be checked, including checking whether the contract information contains the contract address, etc. After completing the two checks, the contract will be persisted, and the new contract will be stored in the metadata database. The actual deployment of the contract is to load the contract into the memory.

In the second step, the call of the contract is the most intuitive feeling for the user to use the smart contract. After the user enters the method name and parameters of the contract, and specifies the address of the contract to be called, the user sends a JSON-RPC request to the JCEE client, and the JCEE The client only needs to encapsulate the relevant parameters and forward them to the JCEE server. The JCEE server will also check the security and completeness, and will enter the corresponding execution process after the check is passed.

In the above step 2, the upgrade of the contract requires the user to provide a new contract file and the old contract address, the old contract address is used to locate and destroy the original contract, and create a new contract on this address, so after the contract is upgraded , the contract address remains unchanged.

In the second step, the freezing of the contract is only to change the status bit of the contract, and the frozen contract can no longer be called, updated and other operations.

In the second step, the unfreezing of the contract needs to provide the contract address of the frozen contract. Similarly, the unfreezing of the contract is only to change the status bit of the contract, and the unfrozen contract can continue to call, update and other operations.

Claims (3)

1. a kind of management method of the intelligent contract life cycle based on JAVA, it is characterised in that comprise the following steps：

Step 1：Contract is disposed：

The client of intelligent contract enforcement engine JCEE based on JAVA virtual machine receives the compressed class file of user's input, After then decompressing class file and persistence, the unique mark contract address ContractAddress of contract is generated, together with class file Address to JCEE server ends send deployment request；JCEE server ends receive JCEE clients hair by monitoring designated port The contract deployment request brought, carries out security inspection to contract first, passes through if checked, contract is persisted into member In database, class file can be then loaded into the deployment that contract is carried out in internal memory；If check not by directly exiting this Secondary contract deployment, and return to error message to JCEE clients.

Step 2：Operation corresponding to being performed according to user's request to contract：

(1) when needing to call contract：JCEE clients receive the calling invoke requests of user's input, parse calling contract Unique mark ContractAddress, contract call method name and parameter, to JCEE server ends send contract call Invoke is asked；JCEE server ends please by monitoring designated port receives that JCEE clients send over and about invoke Ask, security inspection is carried out to contract first, pass through if checked, call the designation method for specifying contract address and synchronous account This information arrives JCEE clients, realizes the calling of contract, if check not by, terminate this contract call, and to JCEE clients return to error message；

(2) when needing to upgrade contract：JCEE clients receive the upgrading update requests of user's input, parse old contract Unique mark ContractAddress, the class file address together with new contract send update requests to JCEE server ends； The contract upgrade request that JCEE server ends receive JCEE clients and sended over by monitoring designated port, enters to contract first Row security inspection, if checked not by directly exiting this contract upgrading, and return to error message to JCEE client End；If inspection passes through, the inquiry of old contract is carried out, if it is possible to inquire old contract, then first destroy old contract, Ran Houchi Change new contract long and load the class file of new contract and the upgrading of contract is completed into internal memory, if old contract can not be found, directly The persistence and loading of the new contract of row are tapped into, completes the upgrading of contract；

(3) when needing to freeze contract：The frozen that freezes that JCEE clients receive user's input is asked, and parses to be freezed The unique mark ContractAddress of contract, the new state position together with contract send freeze request to JCEE server ends； The contract freeze request that JCEE server ends receive JCEE clients and sended over by monitoring designated port, enters to contract first Row security inspection, pass through if checked, the mode bit of renewal contract is frozen states, realizes freezing for contract；If Check not by the way that the contract for then exiting this freezes, and returns to error message to JCEE clients；

(4) when needing defrosting contract：JCEE clients receive the defrosting unfrozen requests of user's input, parse to be solved The unique mark ContractAddress of jelly contract, the new state position together with contract send request of thawing to JCEE server ends； The contract defrosting request that JCEE server ends receive JCEE clients and sended over by monitoring designated port, enters to contract first Row security inspection, pass through if checked, the mode bit of renewal contract is unfrozen states, realizes the defrosting of contract；Such as Fruit is checked not by then exiting this contract and thawing, and return to error message to JCEE clients.

2. the management method of the intelligent contract life cycle based on JAVA as claimed in claim 1, it is characterised in that described In step 1, JCEE servers are managed collectively all intelligent contracts, and contract deployment each time all simply once services to JCEE The calling of device, and go to safeguard without playing a thread for each intelligent contract sheet.

3. the management method of the intelligent contract life cycle based on JAVA as claimed in claim 1, in described step one, JCEE servers are communicated by remote procedure call protocol RPC with JCEE clients, the security inspection of described contract Including checking whether contract bytecode is legal and checks in contract information whether include contract address.