CN116071160A - Block chain-based transaction implementation method, device and computer readable medium - Google Patents

Abstract

This application discloses a blockchain-based transaction implementation method, device, and computer-readable medium. The method acquires transaction information of each transaction in a block on a blockchain node, and constructs each transaction to include each transaction according to the obtained information. The transaction dependency graph of the dependencies between transactions, and according to the transaction dependency graph, determine and output the transaction execution sequence of each transaction, and finally schedule and execute each transaction according to the execution sequence between transactions represented by the transaction execution sequence. It can be seen that this application proposes the idea of combining transaction processes such as green certificate transactions with the blockchain, which can make full use of the advantages of the blockchain to solve the complex transaction process of traditional centralized green certificates, user information that is easy to be tampered with and leaked, and green certificates. Issues such as time-consuming and labor-intensive verification and hard-to-trace voucher records; at the same time, by combining the process of blockchain processing transactions such as green certificate transactions with the transaction dependency graph, it can further adapt to scenarios with strong correlations between transactions. Chain performance requirements.

Description

Blockchain-based transaction implementation method, device, and computer-readable medium

technical field

The present application belongs to the field of block chain application technology, and in particular relates to a block chain-based transaction realization method, device and computer-readable medium.

Background technique

The renewable energy quota system means that the government makes mandatory regulations on the market share of renewable energy power through laws, regulations, etc., and compels electricity sales companies or power consumers to contain a certain proportion of renewable energy power in the electricity used. The green certificate trading system is an important supporting system of the quota system. Since the source of electricity cannot be distinguished from the physical level, the concept of a renewable energy certificate (green certificate) is introduced to represent the amount of renewable energy used. The government needs to issue green certificates corresponding to the amount of on-grid electricity to renewable energy power generation companies, and the subject of quota obligations can purchase green certificates from power generation companies to prove the completion of the quota target.

Traditional green certificate transactions rely on a centralized system. User identity authentication, green certificate issuance, and green certificate transactions are all completed by the centralized system. Not only is the entire transaction process cumbersome, but the transaction data also faces the risk of being illegally tampered with to obtain benefits. risk.

Contents of the invention

In view of this, this application provides a blockchain-based transaction implementation method, device, and computer-readable medium. By combining transaction processes such as green certificate transactions with the blockchain, the advantages of the blockchain are used to solve the problem of traditional center transactions. The transaction process of the green certificate is complicated, the user information is easy to be tampered with and leaked, the issuance of the green certificate is time-consuming and labor-intensive, and the record of the certificate is not easy to trace. Combined to meet the performance requirements of the blockchain in transaction scenarios such as green certificate transactions.

The specific plan is as follows:

A blockchain-based transaction implementation method, comprising:

Obtain the transaction information of each transaction in the block on the blockchain node;

According to the transaction information of each transaction, each transaction is constructed into a transaction dependency graph including dependencies among transactions; the transaction dependency graph is a directed acyclic graph, and the transaction dependency graph includes multiple vertices and Directed edges between vertices, vertices in the transaction dependency graph represent corresponding transactions, and directed edges between vertices represent dependencies between transactions;

Determine and output the transaction execution sequence of each transaction according to the transaction dependency graph;

According to the execution sequence between transactions represented by the output transaction execution sequence, the transactions are scheduled for execution.

Optionally, according to the transaction information of each transaction, each transaction is constructed into a transaction dependency graph including dependencies among transactions, including:

According to the transaction information of each transaction, identify the dependence between transactions between any two transactions in the various transactions;

Constructing a transaction dependency graph corresponding to each transaction according to the identification result of the dependency relationship among the transactions;

Wherein, the directed edge from the first vertex in the transaction dependency graph to the second vertex indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex.

Optionally, determining and outputting the transaction execution sequence of each transaction according to the transaction dependency graph, and scheduling and executing each transaction according to the execution sequence between transactions represented by the output transaction execution sequence, including :

According to the transaction dependency graph, determine and output a transaction execution sequence that can be used to indicate that transactions with dependencies will be executed serially and transactions without dependencies will be executed in parallel;

According to the transaction execution sequence, among the transactions, transactions with dependencies are scheduled for execution in a serial manner, and transactions without dependencies are scheduled for execution in a parallel manner.

Optionally, determining and outputting the transaction execution sequence of each transaction according to the transaction dependency graph, and scheduling and executing each transaction according to the output transaction execution sequence, including:

determining the in-degree of each vertex in the transaction dependency graph that does not implement transaction scheduling;

output each target vertex whose determined current in-degree satisfies the preset in-degree condition;

Hand over the transactions represented by each target vertex whose current in-degree meets the preset in-degree conditions to multiple worker threads for parallel execution;

After the transaction represented by each current target vertex is executed, eliminate the directed edge of each current target vertex pointing to the subsequent node, reduce the in-degree of the corresponding subsequent vertex pointed to by each current target vertex by 1, and return to the determination The step of the in-degree of each vertex in the transaction dependency graph that has not realized the transaction scheduling is used to execute the above processing process cyclically. Through the cyclic execution of the above processing process, there are target vertex strings with dependencies among the target vertices output by different rounds of processing processes. Execute until the transaction represented by each vertex in the transaction dependency graph is executed;

Wherein, the transaction execution sequence includes: during the cyclical execution of the above processing, the transactions respectively represented by the target vertices whose in-degrees output by different rounds of processing sequentially meet the preset in-degree conditions.

Optionally, the transaction is a green certificate transaction;

The block chain network corresponding to the block chain is: the green card transaction block chain network jointly constructed by taking the participants in the green card issuance and transaction process as the main body of the block chain; Before the transaction information of each transaction in the block on the chain node, it also includes:

Receive the block including the transaction information of each green card transaction broadcast by the preset node in the blockchain network.

Optionally, the blockchain node is embedded with a smart contract for realizing the corresponding business process of the green certificate transaction;

The method also includes:

During the execution of the green certificate transaction, the corresponding smart contract is called, and the business data involved in the green certificate transaction is stored on the blockchain node.

Optionally, the smart contract includes a user contract and a green certificate contract;

Among them, the user contract is used to complete the registration of the user's identity on the chain and the user's identity information viewing and verification, and the green certificate contract is used to complete the issuance and transfer of the green certificate.

A blockchain-based transaction implementation device, comprising:

A transaction acquisition unit, configured to acquire the transaction information of each transaction in the block on the blockchain node;

A transaction dependency graph construction unit, configured to construct each transaction into a transaction dependency graph including dependencies among transactions according to the transaction information of each transaction; the transaction dependency graph includes a plurality of vertices and links between vertices Directed edges, vertices in the transaction dependency graph represent corresponding transactions, and directed edges between vertices represent dependencies between transactions;

The transaction scheduling unit is configured to determine and output the transaction execution sequence of each transaction according to the transaction dependency graph, and schedule and execute the transactions according to the execution sequence between transactions represented by the output transaction execution sequence.

Optionally, the transaction dependency graph construction unit is specifically used for:

According to the transaction information of each transaction, identify the dependence between transactions between any two transactions in the various transactions;

Constructing a transaction dependency graph corresponding to each transaction according to the identification result of the dependency relationship among the transactions;

Wherein, the directed edge from the first vertex in the transaction dependency graph to the second vertex indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex.

A computer readable medium on which is stored a computer program comprising program code for performing the method as described in any one of the preceding items.

According to the above scheme, it can be seen that the blockchain-based transaction implementation method, device, and computer-readable medium provided by this application obtain the transaction information of each transaction in the block on the blockchain node, and according to the transaction information of each transaction, each transaction Construct a transaction dependency graph (directed acyclic graph) including the dependencies between transactions, and determine and output the transaction execution sequence of each transaction according to the transaction dependency graph, and finally follow the transaction represented by the output transaction execution sequence The order of execution between transactions is scheduled for execution. It can be seen that this application proposes the idea of combining transaction processes such as green certificate transactions with the blockchain, which can make full use of the advantages of the blockchain to solve the complex transaction process of traditional centralized green certificates, user information that is easy to be tampered with and leaked, and green certificates. Issues such as time-consuming and labor-intensive verification and hard-to-trace voucher records; at the same time, green certificate transactions are one of the transactions with strong correlations between transactions. The combination of ring diagrams can further adapt to the performance requirements of the blockchain in scenarios with strong correlation between transactions such as green certificate transactions.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present application, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is a kind of flowchart of the transaction implementation method based on blockchain provided by the application;

Fig. 2 is another flow chart of the blockchain-based transaction implementation method provided by the present application;

Figure 3 is the overall logical framework of the blockchain-based green certificate transaction provided by this application;

Fig. 4 is an exemplary detailed workflow for processing green card transactions to realize transaction scheduling and execution provided by this application;

Figure 5(a)-Figure 5(g) is an example of the DAG construction process provided by this application;

Figure 6(a)-Figure 6(d) is an example of the output transaction execution sequence according to the generated directed acyclic graph provided by this application;

Fig. 7 is a structural diagram of the block chain-based transaction implementation device provided by the present application.

Detailed ways

For the sake of reference or clarity, the relevant technical terms, abbreviations or nouns involved in the embodiments of the present application are explained as follows:

Blockchain: Blockchain is a new application model of computer technology such as distributed data storage, P2P network, consensus mechanism, encryption algorithm, smart contract, etc. It has the characteristics of decentralization, collective maintenance, programmable, tamper-proof, safe and reliable , traceability and other characteristics.

DAG: Directed Acyclic Graph, that is, directed acyclic graph.

MVCC: Multi-Version Concurrency Control, that is, multi-version concurrency control.

The following will clearly and completely describe the technical solutions in the embodiments of the application with reference to the drawings in the embodiments of the application. Apparently, the described embodiments are only some of the embodiments of the application, not all of them. Based on the embodiments in this application, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the scope of protection of this application.

This application mainly takes the green certificate transaction as an example. Firstly, the green certificate transaction process is combined with the blockchain, and the advantages of the blockchain are used to solve the traditional centralized green certificate transaction process. Issues such as time-consuming and labor-intensive verification and hard-to-trace voucher records.

Blockchain networks generally consist of multiple nodes, each of which stores a complete copy of the data. Transaction execution is essentially that each node performs calculations based on their local data copies. At the same time, it is necessary to ensure the consistency of the calculation results of each node. When the calculation results of each node reach an agreement, each node updates the local data copy. Only in this way can each node be guaranteed The copies of data maintained by each are always identical. The on-chain transaction of the blockchain is completed by calling the smart contract. The smart contract can be regarded as an independent application that communicates with the blockchain nodes through the network. The execution of the on-chain transaction is accompanied by a large number of network I/O , Disk I/O, and computing tasks involving the use of the CPU, the execution process is extremely time-consuming. In order to ensure the consistency of data copies, the traditional blockchain system uses a serial method to execute transactions. The efficiency of serial execution is low and cannot Make full use of the multi-core computing and processing capabilities of modern computer CPUs. For example, only one core of a 6-core CPU is working in serial execution mode, which also causes a waste of system resources. In the green certificate transaction scenario, there are certain requirements for the execution efficiency of the transaction, and the serial execution method of the traditional blockchain cannot meet the requirements of execution efficiency.

Hyperledger Fabric, a representative project in the consortium chain, adopts a transaction concurrent execution strategy based on MVCC. Although transactions can be executed concurrently, in scenarios where transactions are highly correlated, the same block will be generated due to its optimistic concurrency control mechanism. Only the first one of multiple transactions that change the same data can succeed, and the rest will be marked as failed. The applicant found that the failure of these transactions was not caused by the judgment of the business logic layer itself, but by the block Due to the internal mechanism of the chain project, the failed transaction at this time needs to be retried by the business layer, which will also lead to a decrease in performance and processing efficiency, and the green certificate transaction is one of the situations where transactions are highly correlated. To sum up, the current blockchain is difficult to meet the performance requirements in the green certificate transaction scenario.

Based on this, this application further combines the process of processing green certificate transactions in the blockchain with the directed acyclic graph to meet the performance requirements of the blockchain in transaction scenarios with strong correlations between transactions such as green certificate transactions.

In combination with the above research findings, this application provides a blockchain-based transaction implementation method, device, and computer-readable medium. Optionally, the transactions involved can be green certificate transactions, etc., which have certain requirements for transaction execution efficiency and For transactions with strong correlations between transactions, the embodiment of this application will mainly use green certificate transactions as an example to illustrate the solution.

The method and device of this application combine the transaction process of green certificate transactions with blockchain and directed acyclic graph, and mainly involve the preparation of relevant smart contracts required when the transaction process of green certificate transactions is migrated to the blockchain , and the adaptation of the underlying performance optimization of the blockchain.

Among them, all participants in the process of green certificate issuance and transaction are used as the main body to jointly build a green certificate transaction blockchain network. Blockchain network, the blockchain network builds an environment of equality and mutual trust by linking all participants in the green certificate issuance and transaction process in a distributed manner. And pre-develop the corresponding smart contract to migrate the business process of the green certificate transaction to the blockchain or use the smart contract to supplement and improve the original business process.

For green certificate transactions, the smart contracts that need to be implemented mainly include user contracts and green certificate contracts.

The two types of contracts are as follows:

(1) User contract

It is mainly used to complete the registration and on-chain of user identity and view and verify user identity information.

Market participants can use the corresponding management platforms (for example, provincial management platforms) as entrances to register user identities. Each management platform first reviews the qualifications of market participants. For renewable energy suppliers, it is also necessary to confirm that they have renewable power generation capacity. ability to ensure the orderliness of the green certificate market and the legitimacy of the green certificate circulation from the source. Users who pass the review will be assigned a public-private key pair by the platform, the private key will be kept by the user, and the public key will be shared anonymously on the chain by each management platform (for example, each provincial management platform). Subsequent users will use private key signatures when performing operations related to green certificate transactions, such as initiating the transfer of green certificates, to ensure that the operations are initiated by legitimate participants and cannot be repudiated.

(2) Green certificate contract

It is mainly used to complete the issuance and transfer of green certificates.

Issuance of green certificates: Market subject users (such as renewable energy providers) who have passed the registration review can have smart meters installed or upgraded by the grid company. On this basis, suppliers and other users can apply for the issuance of green certificates, and the power grid company will measure their actual grid renewable energy in order to follow the set conversion standards (for example, 1MW·h corresponds to the conversion standard of a green certificate) Generate an equal number of green certificates. Specifically, the measurement results of the power grid company are submitted to the green certificate review agency for review and proofreading. After confirmation, the green certificate review agency generates a green certificate. Each green certificate contains at least the review agency number, Supplier number, green certificate number, green certificate owner number, energy type (wind power/photovoltaic, etc.), issuance time and other information. The review agency of the green certificate will call the smart contract to deposit the green certificate into the supplier's account.

Transfer of green certificates: The transfer of green certificates adopts an on-site trading mechanism. The seller and buyer of the green certificate can list and delist on the trading platform. The seller of the green certificate discloses his intention to sell the green certificate on the trading platform, including information such as the unit price and sales volume of the green certificate. The buyer of the green certificate can obtain the latest market dynamics through the trading platform, select a suitable green certificate seller for transaction negotiation, and when the buyer and the seller reach an agreement on the transaction quantity and transaction unit price, the green certificate buyer will first hand over the prepayment to the trading platform , when the green certificate seller calls the smart contract to complete the transfer of the green certificate, the trading platform will hand over the transaction funds to the green certificate seller. The data to be recorded for each green certificate transfer includes but is not limited to seller number, buyer number, green certificate number, number of green certificates, transaction price, transaction time and other information.

The adaptation of the underlying performance optimization of the blockchain mainly includes two aspects: the construction of the transaction dependency graph and the scheduling of transaction tasks. They are as follows:

Transaction dependency graph construction: According to the relationship between transactions such as green certificate transactions, a batch of transactions in the block are organized into a directed acyclic graph. Each transaction in a block can be regarded as a vertex in the graph (or called a "node" of the graph), and the edges between vertices represent the relationship between two transactions.

Transaction task scheduling: Schedule and execute transactions according to the directed acyclic graph constructed by the transactions in the block. If there is a relationship between the two transactions, let them execute serially, and if the two transactions are not related, let them execute concurrently. Optionally, this process uses the idea of graph topology sorting algorithm to ensure that when a certain transaction is executed, all its previous transactions have been executed.

On this basis, referring to the block chain-based transaction implementation method flow chart shown in Figure 1, the block chain-based transaction implementation method provided by this application at least includes the following processing steps:

Step 101. Obtain the transaction information of each transaction in the block on the blockchain node.

See Figure 1 for an example of the basic transaction structure of the blockchain, which is a typical structure of transaction information in the blockchain. This structure is a general structure. As shown in Figure 1, the basic structure information of the transaction includes but does not It is limited to information such as the transaction initiator (Sender), the called contract name (CallContractName), the called contract method (CallContractMethod), the contract call parameters (CallArgs), the transaction initiator's signature (Signature) on the transaction, and other information. It can include relevant transaction information of both parties to the transaction, such as the seller of the green certificate, the buyer of the green certificate, the number of green certificate transactions, etc.

Table 1 Blockchain transaction structure

When executing a transaction, the blockchain can locate a specific smart contract and a specific contract method according to the contract name (CallContractName), the called contract method (CallContractMethod) and the contract call parameters (CallArgs), and then give specific contract call parameters to This completes the call of the contract method to carry different business logic. For example, CallContractName=Proof and CallContractMethod=StoreProof can locate the proof storage method of the proof storage contract, and then give the parameter CallArgs required for calling the method, and call StoreProof to complete the proof storage business logic.

For green certificate transactions, the blockchain network corresponding to the blockchain can be: a green certificate transaction blockchain network jointly constructed by taking all participants in the green certificate issuance and transaction process as the main body of the blockchain.

Before step 101, the application method may further include: receiving a block including transaction information of each green card transaction broadcast by a preset node in the blockchain network.

The preset node here can be the leader node selected from the blockchain nodes based on the consensus algorithm.

In this application, the on-chain transaction processing in the blockchain network takes blocks as units, and the consensus algorithm selects transactions from the leader node selected from the blockchain nodes, packages the selected transactions into blocks and broadcasts them to the blockchain Other nodes in the network, nodes in the blockchain network (that is, blockchain nodes) each process the transaction locally after receiving the block.

When the blockchain nodes receive the block and process the transaction locally, they first obtain the transaction information of each transaction in the block, such as transaction ID, green certificate seller, green certificate buyer, green certificate transaction quantity, etc.

Step 102: Construct each transaction into a corresponding transaction dependency graph according to the transaction information of each transaction; the transaction dependency graph is a directed acyclic graph, and the transaction dependency graph includes multiple vertices and The directed edges in the transaction dependency graph represent the corresponding transactions, and the directed edges between the vertices represent the dependencies between transactions.

Afterwards, according to the transaction information of each transaction in the block, the dependencies between any two transactions in each transaction are identified, and according to the identification results of the dependencies between each transaction, the DAG form of transaction dependencies corresponding to each transaction is constructed. picture. Therefore, the transaction process of blockchain processing green certificate transactions and other transactions is combined with the directed acyclic graph, and the directed acyclic graph is used to describe the relationship between green certificate transactions.

Among them, the directed edge from the first vertex to the second vertex in the transaction dependency graph indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex. For example, the directed edge from vertex x to vertex y represents the vertex The transaction represented by y must wait for the execution of the transaction represented by vertex x to be executed, so the directed edge also represents the execution sequence of the two connected vertices.

Step 103: Determine and output the transaction execution sequence of each transaction according to the transaction dependency graph.

On this basis, according to the transaction dependency graph, determine and output the transaction execution sequence for each transaction. Among them, the purpose of the transaction execution sequence is to indicate that the associated transactions in the block are executed serially, and the unrelated transactions are executed in parallel/concurrently, so as to ensure the correctness of the transaction execution results and at the same time have a certain degree of concurrency, making full use of the modern The computing and processing capabilities of the computer CPU's multi-core are used to improve the efficiency of transaction processing and meet the performance requirements of the blockchain in the green certificate transaction scenario.

Step 104: Schedule and execute each transaction according to the execution order of the transactions represented by the output transaction execution sequence.

Correspondingly, according to the output transaction execution sequence, the transactions that have dependencies among the transactions in the block can be scheduled and executed in a serial manner, and the transactions without dependencies can be scheduled and executed in a parallel manner.

A specific implementation of step 103-step 104 is provided below, referring to Fig. 2, step 103-step 104 can be realized through the following processing to determine and output the transaction execution sequence of each transaction according to the transaction dependency graph, and according to the output transaction execution sequence The process of scheduling execution of each transaction:

11) Determine the in-degree of each vertex in the transaction dependency graph that has not realized transaction scheduling;

12) Outputting each target vertex whose determined current in-degree satisfies the preset in-degree condition;

Wherein, the preset in-degree condition may be set as: the in-degree of the vertex is 0.

If the in-degree of a vertex is 0, it means that other transactions that the transaction represented by the vertex depends on are currently completed, or that the transaction represented by the vertex does not depend on any other transactions.

13) Hand over the transactions represented by each target vertex whose current in-degree satisfies the preset in-degree condition to multiple worker threads for parallel execution;

14) After the transaction represented by each current target vertex is executed, eliminate the directed edge from each current target vertex pointing to the subsequent node, reduce the in-degree of the corresponding subsequent vertex pointed to by each current target vertex by 1, and return to step 11 ), execute the above processing process in a loop, through the loop execution of the above processing process, the target vertices that have dependencies among the target vertices output by different rounds of processing processes are executed serially until the transaction represented by each vertex in the transaction dependency graph is executed.

Wherein, the transaction execution sequence includes: during the cyclical execution of the above processing, the in-degrees sequentially output by different rounds of processing processes respectively represent the transactions represented by the target vertices whose in-degrees satisfy the preset in-degree conditions

In this implementation, the vertices with an input degree of 0 are continuously output, and the transactions represented by the vertices with an input degree of 0 in the same batch output at the same time sequence point (that is, the output of the same round of processing) are scheduled in a parallel/concurrent manner Execution, the transactions represented by vertices whose in-degree is 0 in different batches output at different timing points are executed in chronological order, so as to realize parallel/concurrent execution of unrelated transactions in the block, and serial execution of associated transactions, both It can ensure the correctness of transaction execution results and at the same time ensure a certain degree of concurrency.

According to the above scheme, it can be seen that the block chain-based transaction implementation method provided by this application obtains the transaction information of each transaction in the block on the block chain node, and constructs each transaction to include the transaction information between each transaction according to the transaction information of each transaction. The transaction dependency graph (directed acyclic graph) of the dependency relationship, and according to the transaction dependency graph, determine and output the transaction execution sequence of each transaction, and finally according to the execution order between transactions represented by the output transaction execution sequence, each Transactions are scheduled for execution. It can be seen that this application proposes the idea of combining transaction processes such as green certificate transactions with the blockchain, which can make full use of the advantages of the blockchain to solve the complex transaction process of traditional centralized green certificates, user information that is easy to be tampered with and leaked, and green certificates. Issues such as time-consuming and labor-intensive verification and hard-to-trace voucher records; at the same time, green certificate transactions are one of the transactions with strong correlations between transactions. The combination of ring diagrams can further adapt to the performance requirements of the blockchain in scenarios with strong correlation between transactions such as green certificate transactions.

Optionally, in an embodiment, the blockchain nodes of the blockchain network are embedded with smart contracts for realizing the corresponding business processes of green certificate transactions. Referring to the flow chart of the blockchain-based transaction implementation method shown in Figure 2, the blockchain-based transaction implementation method disclosed in this application may also include the following processing:

Step 105: Invoke the corresponding smart contract during the execution of the green certificate transaction, and store the business data involved in the green certificate transaction into the blockchain node.

For green certificate transactions, as mentioned above, smart contracts mainly include user contracts and green certificate contracts. Among them, user contracts are mainly used to complete user identity registration on-chain and user identity information viewing and verification, and green certificate contracts are mainly used It is used to complete the issuance and transfer of green certificates.

Correspondingly, during the execution of the green certificate transaction, the corresponding smart contract is invoked to store the business data corresponding to the green certificate exchange into the blockchain node, which may include but not limited to, call the user contract to register the identity on the blockchain or user Check and verify identity information, and store the identity registration information or verification information involved in the blockchain node, and call the green certificate contract for green certificate issuance, green certificate transfer, etc., and store the relevant green certificates involved Data such as issuance and green certificate transfer are stored in the blockchain nodes, so as to realize the effective migration and adaptation of the business process of green certificate transactions to the blockchain.

An application example of the method of the present application is further provided below.

This example takes the scheduling and execution of green certificate transactions as an example. It mainly involves the compilation of relevant smart contracts required when the green certificate transaction process is migrated to the blockchain, and the adaptation of the underlying performance optimization of the blockchain. See Figure 3. The overall logical framework of the green certificate transaction of the blockchain (the dotted line in the figure is the core improvement part provided by this application scheme), among which, for the preparation of the required smart contracts, two types of smart contracts, the user contract and the green certificate contract, are mainly implemented (that is, the dotted line box on the right side of the figure), the logic/functions of the two types of smart contracts are described above, and the method of smart contracts will be called during transaction execution to store specific business data on the blockchain, such as user contracts Identity registration, green certificate issuance of green certificate contracts, transfer of green certificates, etc.

For the adaptation of the underlying performance optimization of the blockchain, a new DAG module (that is, the dotted box on the left in the figure) is added to the blockchain node software. The DAG module is responsible for receiving the block delivered by the block execution module, and the The transactions are constructed into a DAG, which is scheduled and executed by the transaction execution thread pool. At the same time, the DAG module will record the results generated by all transaction executions, and return the results to the block execution module, which will submit the data to the ledger .

In this example, see Figure 3, the adaptation of the underlying performance optimization of the blockchain is realized by further dividing the DAG module into two sub-modules, transaction dependency graph construction and transaction task scheduling, among which:

The transaction dependency graph construction sub-module is used to organize a batch of transactions in the block into a directed acyclic graph according to the association relationship between green certificate transactions. Each transaction in the block can be regarded as a vertex in the graph, and the edge between the vertices represents the relationship between the two transactions.

The transaction task scheduling sub-module is used to schedule and execute transactions according to the directed acyclic graph constructed for intra-block transactions. If there is a relationship between the two transactions, let them be executed serially; if there is no relationship between the two transactions, let them execute in parallel. This process can use the idea of the topological sorting algorithm of the graph to ensure that when a certain transaction is executed , all previous transactions have been executed.

When processing the green certificate transaction to realize the scheduling execution of the transaction, based on the corresponding sub-modules in the above two sub-modules, read the transaction information in the block, identify the dependencies of the transactions, and then identify the differences between transactions based on the dependencies of the transactions Association relationship, the transaction is constructed into a transaction dependency graph (DAG graph), and finally the transaction execution sequence is output through the graph, and the transaction is scheduled in parallel or serially. The basic workflow is shown in Figure 4, and the workflow is further detailed below illustrate.

Referring to Figure 4, in this example, an exemplary detailed workflow for processing green card transactions to implement transaction scheduling is as follows:

21) Initialize the task queue and the worker thread equal to the number of CPU cores. The worker thread continuously obtains transactions from the task queue for processing. The transactions in the task queue correspond to the transactions in the block one by one, and the structural information is the same. In the initial state, the task queue is empty, and the worker threads are all blocked.

22) Identify the dependencies between transactions in the block, and construct the transactions in the block into a DAG.

In the example shown in Figure 5(a), transactions are first taken out of the block, and each transaction represents a transfer process of a green certificate. In the initial state, each transaction is regarded as a node in a two-dimensional plane.

Continue to refer to the schematic diagram of the DAG construction process provided in Figure 5(b)-Figure 5(g). The transactions in the block have a certain order, and each transaction is read in turn according to the transaction order, and the dependencies of the transaction are extracted, that is, the green certificate. buyer and seller. If two transactions have the same dependencies or there is an intersection of dependencies, connect the nodes corresponding to the two transactions with a directed edge. Taking Figure 5(d) as an example, transaction 1 and transaction 3 are both for user A A modification has been made, that is, there is an intersection between the dependencies of transaction 1 and transaction 3, and the two transactions are related to each other, and a directed edge from node 1 to node 3 is added. Taking Figure 5(e) again as an example, transaction 4 modifies user B and user C, user B has been modified by transaction 1 before, and user C has been modified by transaction 3 before, so add between node 1 and node 4 A directed edge from node 1 to node 4, and a directed edge from node 3 to node 4 is added between node 3 and node 4. The directed edge from node x to node y means that the transaction represented by node y must wait for the transaction represented by node x to be executed before it can be executed, that is, the directed edge represents the execution order of the two connected nodes.

This process is repeated, and when the transactions in the block are read, the nodes in the plane in step 2) also form a directed acyclic graph through dependencies.

23) Output the transaction execution sequence according to the generated directed acyclic graph, so as to perform serial/parallel scheduling execution on the transactions according to the transaction execution sequence.

Specifically, as shown in Figure 6(a)-Figure 6(d), when outputting the transaction execution sequence according to the generated DAG, first calculate the current unimplemented value in the DAG based on the DAG Scheduling the in-degree of each vertex/node for execution, and then continuously outputting vertices/nodes with an in-degree of 0. The transactions represented by these vertices/nodes in the same batch output by the same timing node do not depend on other transactions and can be directly executed in parallel , Throw it to the task queue accordingly, and wake up the worker thread to process the transaction in parallel. After the transaction is executed, eliminate the directed edge of this node pointing to the subsequent node, and reduce the in-degree of the subsequent node by 1 to generate a new round Nodes with an in-degree of 0 repeat this process until the transaction is executed.

The traditional blockchain uses a serial execution mode to process transactions within a block. Serial execution means that only one transaction processing thread is working, and each transaction is processed in sequence. A transaction processing thread uses at most one core of the CPU of the host where the blockchain node is located, and modern computer CPUs are generally multi-core. At this time, the CPU resources of the host where the blockchain node is located are not fully utilized. In addition, the efficiency of serial transaction processing is also very high. Low. If you want to improve the transaction processing capability of blockchain nodes by improving the host configuration, it is extremely limited, at least increasing the number of CPU cores cannot improve transaction processing capabilities.

The applicant's research found that the reason why the traditional blockchain adopts serial execution is to solve the uncertainty that may be caused by concurrent execution of transactions under multiple nodes. For example, in the transfer scenario, user A initiates two transfer transactions at the same time, transaction 1: user A transfers 20 to user B; transaction 2: user A transfers 30 to user C. If the balance of user A is only 30, then this means that only one of the two transfer transactions will succeed, and the other will fail due to insufficient balance of user A. In the case of multiple nodes in the blockchain, concurrent execution may generate transaction 1, transaction 2 and transaction 2, transaction 1, which means that on some nodes, transaction 1 succeeds, while on other nodes , transaction 2 is successful, which will cause data inconsistency of each node. In another case, user A and user B initiate two transfer transactions at the same time, transaction 1: user A transfers 20 to user C, transaction 2: user B transfers 30 to user D, in this case, no matter according to transaction 1, Whether transaction 2 or transaction 2, transaction 1 is executed in this order will produce consistent results. Based on the above two situations, it can be known that when transactions are related, they need to be executed serially in order to avoid the uncertainty of execution results caused by concurrent execution; and when there is no connection between transactions, It can be executed concurrently. At this time, serial execution and concurrent execution can always produce the same execution result.

Based on the above research, this application organizes the transactions into a directed acyclic graph by identifying the relationship between transactions. If two transactions are related, a directed edge is added between the two transactions, and finally through the directed The acyclic graph outputs the order of transaction execution, allowing associated transactions to execute serially, eliminating the uncertainty caused by concurrent execution of associated transactions, allowing unrelated transactions to execute concurrently, which can make full use of the multi-core processing capabilities of modern computer CPUs, and Applying this idea to transaction scenarios such as green certificate transactions that require transaction execution efficiency and strong correlation between transactions can effectively adapt to the performance requirements of blockchain in transaction scenarios such as green certificate transactions.

Corresponding to the above blockchain-based transaction implementation method, the embodiment of the present application also discloses a blockchain-based transaction implementation device. The composition and structure of the device is shown in Figure 7, including:

A transaction acquisition unit 701, configured to acquire the transaction information of each transaction in the block on the blockchain node;

A transaction dependency graph constructing unit 702, configured to construct each transaction into a transaction dependency graph including dependencies among transactions according to the transaction information of each transaction; the transaction dependency graph includes a plurality of vertices and between vertices The directed edges in the transaction dependency graph represent the corresponding transactions, and the directed edges between the vertices represent the dependencies between transactions;

The transaction scheduling unit 703 is configured to determine and output the transaction execution sequence of each transaction according to the transaction dependency graph, and schedule and execute the transactions according to the execution sequence between transactions represented by the output transaction execution sequence .

In one embodiment, the transaction dependency graph construction unit 702 is specifically used for:

According to the transaction information of each transaction, identify the dependence between transactions between any two transactions in the various transactions;

Constructing a transaction dependency graph corresponding to each transaction according to the identification result of the dependency relationship among the transactions;

Wherein, the directed edge from the first vertex in the transaction dependency graph to the second vertex indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex.

In one embodiment, the transaction scheduling unit 703 is specifically used to:

According to the transaction dependency graph, determine and output a transaction execution sequence that can be used to indicate that transactions with dependencies will be executed serially and transactions without dependencies will be executed in parallel;

According to the transaction execution sequence, among the transactions, transactions with dependencies are scheduled for execution in a serial manner, and transactions without dependencies are scheduled for execution in a parallel manner.

In one embodiment, the transaction scheduling unit 703 is specifically used to:

determining the in-degree of each vertex in the transaction dependency graph that does not implement transaction scheduling;

output each target vertex whose determined current in-degree satisfies the preset in-degree condition;

Hand over the transactions represented by each target vertex whose current in-degree satisfies the preset in-degree condition to multiple worker threads for parallel execution;

After the transaction represented by each current target vertex is executed, eliminate the directed edge of each current target vertex pointing to the subsequent node, reduce the in-degree of the corresponding subsequent vertex pointed to by each current target vertex by 1, and return to the determination The step of the in-degree of each vertex in the transaction dependency graph that has not realized the transaction scheduling is used to execute the above processing process cyclically. Through the cyclic execution of the above processing process, there are target vertex strings with dependencies among the target vertices output by different rounds of processing processes. Execute until the transaction represented by each vertex in the transaction dependency graph is executed;

Wherein, the transaction execution sequence includes: during the cyclical execution of the above processing, the transactions respectively represented by the target vertices whose in-degrees output by different rounds of processing sequentially meet the preset in-degree conditions.

In one embodiment, the transaction is a green card transaction;

The blockchain network corresponding to the blockchain is: the green certificate transaction blockchain network jointly constructed by taking the participants in the green certificate issuance and transaction process as the main body of the blockchain;

The above device also includes: a block receiving unit, used to receive the transaction information broadcast by the preset node in the blockchain network including the transaction information of each green card transaction before obtaining the transaction information of each transaction in the block on the blockchain node blocks.

In one embodiment, the blockchain node is embedded with a smart contract for realizing the corresponding business process of the green certificate transaction;

The above device also includes a contract calling unit, which is used to call the corresponding smart contract during the execution of the green certificate transaction, and store the business data involved in the green certificate transaction into the block chain node.

In one embodiment, the smart contract includes a user contract and a green card contract;

Among them, the user contract is used to complete the registration of the user's identity on the chain and the viewing and verification of the user's identity information, and the green certificate contract is used to complete the issuance and transfer of the green certificate.

For the block chain-based transaction implementation device disclosed in the embodiment of this application, since it corresponds to the block chain-based transaction implementation method disclosed in the method embodiment above, the description is relatively simple. For related similarities, please refer to Just refer to the descriptions of the method embodiments above, and details will not be described here.

In addition, the present application also provides a computer-readable medium on which a computer program is stored, and the computer program includes a program code for executing the method for realizing a transaction based on blockchain as disclosed in any method embodiment above.

In the context of this application, a computer-readable medium (machine-readable medium) may be a tangible medium that may contain or be stored for use by or in conjunction with an instruction execution system, apparatus, or device program of. A machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media would include one or more wire-based electrical connections, portable computer discs, hard drives, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory), optical fiber, compact disk read only memory (CD-ROM), optical storage, magnetic storage, or any suitable combination of the foregoing.

It should be noted that the computer-readable medium mentioned above in the present disclosure may be a computer-readable signal medium or a computer-readable storage medium or any combination of the two. A computer readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to, electrical connections with one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable Programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination of the above. In the present disclosure, a computer-readable storage medium may be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In the present disclosure, however, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave carrying computer-readable program code therein. Such propagated data signals may take many forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the foregoing. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which can transmit, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device . Program code embodied on a computer readable medium may be transmitted by any appropriate medium, including but not limited to wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

The above-mentioned computer-readable medium may be included in the electronic device, or may exist independently without being incorporated into the electronic device.

To sum up, compared with the prior art, the blockchain-based transaction realization method, device and computer-readable medium disclosed in the embodiment of the present application have at least the following technical advantages:

a) Combine the green certificate transaction process with the blockchain, and propose a set of implementation methods for relevant smart contracts in the green certificate scenario, and use the advantages of the blockchain to solve the complex transaction process of the traditional centralized green certificate and easy access to user information. Tampering is easy to leak, the issuance of green certificates is time-consuming and labor-intensive, and the voucher records are not easy to trace.

b) Combining the process of processing green card transactions in blockchain with directed acyclic graph, using directed acyclic graph to describe the relationship between green card transactions, and combining directed acyclic graph and topological sorting to output transactions Execution sequence, parallel or serial scheduling and execution of transactions, effectively improves the system throughput of the blockchain, and can adapt to the performance requirements of the blockchain in the green certificate transaction scenario.

It should be noted that each embodiment in this specification is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. For the same and similar parts in each embodiment, refer to each other, that is, Can.

For the convenience of description, when describing the above system or device, functions are divided into various modules or units and described separately. Of course, when implementing the present application, the functions of each unit can be implemented in one or more pieces of software and/or hardware.

It can be known from the above description of the implementation manners that those skilled in the art can clearly understand that the present application can be implemented by means of software plus a necessary general-purpose hardware platform. Based on this understanding, the essence of the technical solution of this application or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in storage media, such as ROM/RAM, disk , CD, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments of the present application.

Finally, it should also be noted that in this text, relational terms such as first, second, third, and fourth, etc. are only used to distinguish one entity or operation from another entity or operation, and not Any such actual relationship or order between these entities or operations is necessarily required or implied. Furthermore, the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a process, method, article, or apparatus comprising a set of elements includes not only those elements, but also includes elements not expressly listed. other elements of or also include elements inherent in such a process, method, article, or device. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article or apparatus comprising said element.

The above description is only the preferred embodiment of the present application. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present application, some improvements and modifications can also be made. These improvements and modifications are also It should be regarded as the protection scope of this application.

Claims (10)

1. A blockchain-based transaction implementation method, characterized in that, comprising: Obtain the transaction information of each transaction in the block on the blockchain node; According to the transaction information of each transaction, each transaction is constructed into a transaction dependency graph including dependencies among transactions; the transaction dependency graph is a directed acyclic graph, and the transaction dependency graph includes multiple vertices and Directed edges between vertices, vertices in the transaction dependency graph represent corresponding transactions, and directed edges between vertices represent dependencies between transactions; Determine and output the transaction execution sequence of each transaction according to the transaction dependency graph; According to the execution sequence between transactions represented by the output transaction execution sequence, the transactions are scheduled for execution. 2. The method according to claim 1, characterized in that, according to the transaction information of each transaction, each transaction is constructed into a transaction dependency graph including dependencies among transactions, including: According to the transaction information of each transaction, identify the dependence between transactions between any two transactions in the various transactions; Constructing a transaction dependency graph corresponding to each transaction according to the identification result of the dependency relationship among the transactions; Wherein, the directed edge from the first vertex in the transaction dependency graph to the second vertex indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex. 3. The method according to claim 1, characterized in that, according to the transaction dependency graph, the transaction execution sequence of each transaction is determined and output, according to the execution order between transactions represented by the output transaction execution sequence , to schedule and execute each transaction, including: According to the transaction dependency graph, determine and output the transaction execution sequence that can be used to indicate the serial execution sequence of transactions with dependencies and the parallel execution of transactions without dependencies; According to the transaction execution sequence, among the transactions, transactions with dependencies are scheduled for execution in a serial manner, and transactions without dependencies are scheduled for execution in a parallel manner. 4. The method according to claim 1, wherein the transaction execution sequence of each transaction is determined and output according to the transaction dependency graph, and the transactions are scheduled according to the output transaction execution sequence Execution, including: determining the in-degree of each vertex in the transaction dependency graph that does not implement transaction scheduling; output each target vertex whose determined current in-degree satisfies the preset in-degree condition; Hand over the transactions represented by each target vertex whose current in-degree satisfies the preset in-degree condition to multiple worker threads for parallel execution; After the transaction represented by each current target vertex is executed, eliminate the directed edge of each current target vertex pointing to the subsequent node, reduce the in-degree of the corresponding subsequent vertex pointed to by each current target vertex by 1, and return to the determination The step of the in-degree of each vertex in the transaction dependency graph that has not realized the transaction scheduling is used to execute the above processing process cyclically. Through the cyclic execution of the above processing process, there are target vertex strings with dependencies among the target vertices output by different rounds of processing processes. Execute until the transaction represented by each vertex in the transaction dependency graph is executed; Wherein, the transaction execution sequence includes: during the cyclical execution of the above processing, the transactions respectively represented by the target vertices whose in-degrees output by different rounds of processing sequentially meet the preset in-degree conditions. 5. The method according to claim 1, wherein the transaction is a green card transaction; The block chain network corresponding to the block chain is: the green card transaction block chain network jointly constructed by taking the participants in the green card issuance and transaction process as the main body of the block chain; Before the transaction information of each transaction in the block on the chain node, it also includes: Receive the block including the transaction information of each green card transaction broadcast by the preset node in the blockchain network. 6. The method according to claim 5, characterized in that, the blockchain node is embedded with a smart contract for realizing the corresponding business process of the green certificate transaction; The method also includes: During the execution of the green certificate transaction, the corresponding smart contract is called, and the business data involved in the green certificate transaction is stored on the blockchain node. 7. The method according to claim 6, wherein the smart contract includes a user contract and a green card contract; Among them, the user contract is used to complete the registration of the user's identity on the chain and the user's identity information viewing and verification, and the green certificate contract is used to complete the issuance and transfer of the green certificate. 8. A blockchain-based transaction implementation device, characterized in that it comprises: A transaction acquisition unit, configured to acquire the transaction information of each transaction in the block on the blockchain node; A transaction dependency graph construction unit, configured to construct each transaction into a transaction dependency graph including dependencies among transactions according to the transaction information of each transaction; the transaction dependency graph includes a plurality of vertices and links between vertices Directed edges, vertices in the transaction dependency graph represent corresponding transactions, and directed edges between vertices represent dependencies between transactions; The transaction scheduling unit is configured to determine and output the transaction execution sequence of each transaction according to the transaction dependency graph, and schedule and execute the transactions according to the execution sequence between transactions represented by the output transaction execution sequence. 9. The device according to claim 8, wherein the transaction dependency graph construction unit is specifically used for: According to the transaction information of each transaction, identify the dependence between transactions between any two transactions in the various transactions; Constructing a transaction dependency graph corresponding to each transaction according to the identification result of the dependency relationship among the transactions; Wherein, the directed edge from the first vertex in the transaction dependency graph to the second vertex indicates that the transaction represented by the second vertex depends on the transaction represented by the first vertex. 10. A computer-readable medium, characterized in that a computer program is stored thereon, the computer program comprising program code for executing the method according to any one of claims 1-7.

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