Blockchain-based content verification

A non-transitory, computer-readable medium storing one or more instructions executable by a computer system to perform operations comprising:

• receiving, from a client device of a signer, a target transaction request for triggering presentation of a target electronic document;
• invoking a smart contract for content verification of the target electronic document in response to receiving the target transaction request;
• executing a content verification program declared in the smart contract, the executing including:
• reading content of the target electronic document from a blockchain comprising a main chain and a plurality of child chains, wherein:
• the plurality of child chains comprise a first child chain for storing an access address and summary information of the target electronic document uploaded by a contract drafter and a second child chain for storing the content of the target electronic document;
• and
• reading the content of the target electronic document from the blockchain comprises:
• reading the access address of the target electronic document from the first child chain;
• and
• reading the content of the target electronic document from the second child chain based on the access address of the target electronic document;
• and
• performing content verification on the target electronic document based on the content of the target electronic document read from the blockchain;
• and
• returning a content verification result and the content of the target electronic document to the client device for presentation to the signer.

A computer-implemented system, comprising:

• one or more computers;
• and
• one or more computer memory devices interoperably coupled with the one or more computers and having tangible, non-transitory, machine-readable media storing one or more instructions that, when executed by the one or more computers, perform one or more operations comprising:
• receiving, from a client device of a signer, a target transaction request for triggering presentation of a target electronic document;
• invoking a smart contract for content verification of the target electronic document in response to receiving the target transaction request;
• executing a content verification program declared in the smart contract, the executing including:
• reading content of the target electronic document from a blockchain comprising a main chain and a plurality of child chains, wherein:
• the plurality of child chains comprise a first child chain for storing an access address and summary information of the target electronic document uploaded by a contract drafter and a second child chain for storing the content of the target electronic document;
• and
• reading the content of the target electronic document from the blockchain comprises:
• reading the access address of the target electronic document from the first child chain;
• and
• reading the content of the target electronic document from the second child chain based on the access address of the target electronic document;
• and
• performing content verification on the target electronic document based on the content of the target electronic document read from the blockchain;
• and
• returning a content verification result and the content of the target electronic document to the client device for presentation to the signer.