Abstract: Embodiments of the present specification disclose methods, apparatuses, and devices for transferring data assets based on a blockchain. One method includes: obtaining usage demand information of a data requestor for using original data, wherein the usage demand information indicates a demand of the data requestor for performing computations based on the original data; sending a usage authorization request for the original data to a data owner of the original data based on a decentralized identifier (DID) corresponding to the original data; receiving confirmation information of the usage authorization request from the data owner; processing the original data based on the usage demand information to obtain a processing result; transmitting the processing result to the data requestor; and generating a verifiable claim (VC) for recording usage information of the original data.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based service processing. One of the methods includes receiving a service processing request by a first service processing platform from a first user. The first service processing platform is one of a plurality of service processing platforms that access a blockchain network, and service data of the first user is shared between the plurality of service processing platforms over the blockchain network. In response to a determination that the service processing request involves a second service processing platform of the plurality of service processing platforms, it is determined whether the service processing request is permitted to be executed. In response to determining that the service processing request is permitted to be executed, the service processing request is executed over the blockchain network.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based service processing. One of the methods includes receiving a service processing request by a first service processing platform from a first user. The first service processing platform is one of a plurality of service processing platforms that access a blockchain network, and service data of the first user is shared between the plurality of service processing platforms over the blockchain network. In response to a determination that the service processing request involves a second service processing platform of the plurality of service processing platforms, it is determined whether the service processing request is permitted to be executed. In response to determining that the service processing request is permitted to be executed, the service processing request is executed over the blockchain network.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based data synchronization, are provided. One of the methods includes: obtaining, from one or more blockchain nodes associated with a blockchain, data associated with a plurality of blockchain transactions recorded in one or more blocks of the blockchain; storing the obtained data in one or more data stores, wherein the storing comprises organizing the obtained data according to one or more schemas, at least one of the one or more schemas being different from a data structure of the blockchain; receiving, from a client device, a data query based on one of the one or more schemas; executing the data query on the data in the one or more data stores to obtain a result; and sending, to the client device, a response comprising the obtained result.

Abstract: Disclosed herein are methods, systems, and media for backtracking a user's operation of services. One method comprises: receiving an authorization request from a service device, the authorization request based on a service processing request from a client device, and comprises: data corresponding to a user's operation related to a service, authorization information for accessing the data granted to the service device; a first digital identity of the user; and a second digital identity of the service device; in response to determining that the authorization information satisfies a condition, generating a claim based on the data, the authorization information, the first digital identity, and the second digital identity; recording the claim to a blockchain; and in response to determining that a supervising user has permission to access the claim, granting permission to the supervising user to backtrack the user's operation corresponding to the service based on the claim in the blockchain.

Abstract: Disclosed herein are methods, systems, and media for backtracking a user's operation of services. One method comprises: receiving an authorization request from a service device, the authorization request based on a service processing request from a client device, and comprises: data corresponding to a user's operation related to a service, authorization information for accessing the data granted to the service device; a first digital identity of the user; and a second digital identity of the service device; in response to determining that the authorization information satisfies a condition, generating a claim based on the data, the authorization information, the first digital identity, and the second digital identity; recording the claim to a blockchain; and in response to determining that a supervising user has permission to access the claim, granting permission to the supervising user to backtrack the user's operation corresponding to the service based on the claim in the blockchain.

Abstract: Disclosed herein are systems, methods, and media for processing and updating risk assessment information of a user. One of the methods here comprise: obtaining risk assessment information and digital identity of the user; creating a first verifiable claim based on the digital identity and the risk assessment information by using a first blockchain, revoking a second verifiable claim of original risk assessment information corresponding to the digital identity by using the first blockchain; uploading the first verifiable claim to a second blockchain; obtaining a storage credential of the first verifiable claim in the second blockchain, wherein the second blockchain is connected to a service processing platform; generating a risk assessment card corresponding to the user based on the storage credential and the first verifiable claim; and allowing the service processing platform to obtain the risk assessment information of the user from the second blockchain by using the risk assessment card.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for implementing a blockchain-based decentralized application, are provided. One of the methods includes: generating a request to an external service based on a software development kit (SDK) associated with the external service, wherein the SDK is integrated with a client-side application on the client device; sending the request to a server associated with the external service; obtaining, from the server associated with the external service, a result responsive to the request; generating a blockchain transaction based on the result from the external service, wherein the blockchain transaction invokes a blockchain contract deployed on a blockchain; sending the blockchain transaction to one or more blockchain nodes for adding to the blockchain; and obtaining, from one or more data stores synchronized with the blockchain, one or more return values associated with adding the blockchain transaction to the blockchain.

Abstract: Disclosed herein are methods, systems, and media for obtaining a user's risk assessment information. An example method includes obtaining risk assessment information by performing risk assessment on a user; obtaining the user's digital identity; creating a first verifiable claim based on the digital identity and risk assessment information using a first blockchain, wherein the first verifiable claim comprises the risk assessment information; uploading the first verifiable claim to a second blockchain and obtaining a storage credential of the first verifiable claim in the second blockchain; generating a risk assessment card for the user based on the storage credential and the first verifiable claim, wherein the second blockchain is connected to a service processing platform; and providing access to the service processing platform to obtain the risk assessment information of the user from the second blockchain in response to determining that the service processing platform uses the risk assessment card.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based resource transaction. One of the method includes receiving a resource transaction request by a first resource trading platform connected to a blockchain network from a first user to execute a first resource transaction related to risk assessment. Authorization information of a risk assessment card of the first user is queried from an authorization management platform that is connected to the blockchain network. If it is determined that the first resource trading platform is authorized to obtain risk assessment data of the first user, the risk assessment data of the first user is obtained from a blockchain node of the blockchain network. It is determined, based on the risk assessment data of the first user, whether to execute the first resource transaction for the first user.

Abstract: Disclosed herein are systems, methods, and media for processing and updating risk assessment information of a user. One of the methods here comprise: obtaining risk assessment information and digital identity of the user; creating a first verifiable claim based on the digital identity and the risk assessment information by using a first blockchain, revoking a second verifiable claim of original risk assessment information corresponding to the digital identity by using the first blockchain; uploading the first verifiable claim to a second blockchain; obtaining a storage credential of the first verifiable claim in the second blockchain, wherein the second blockchain is connected to a service processing platform; generating a risk assessment card corresponding to the user based on the storage credential and the first verifiable claim; and allowing the service processing platform to obtain the risk assessment information of the user from the second blockchain by using the risk assessment card.

Abstract: Embodiments of the present specification disclose methods, apparatuses, and devices for transferring data assets based on a blockchain. One method includes: obtaining usage demand information of a data requestor for using original data, wherein the usage demand information indicates a demand of the data requestor for performing computations based on the original data; sending a usage authorization request for the original data to a data owner of the original data based on a decentralized identifier (DID) corresponding to the original data; receiving confirmation information of the usage authorization request from the data owner; processing the original data based on the usage demand information to obtain a processing result; transmitting the processing result to the data requestor; and generating a verifiable claim (VC) for recording usage information of the original data.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based service processing. One of the methods includes receiving a service processing request by a first service processing platform from a first user. The first service processing platform is one of a plurality of service processing platforms that access a blockchain network, and service data of the first user is shared between the plurality of service processing platforms over the blockchain network. In response to a determination that the service processing request involves a second service processing platform of the plurality of service processing platforms, it is determined whether the service processing request is permitted to be executed. In response to determining that the service processing request is permitted to be executed, the service processing request is executed over the blockchain network.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based decentralized application development, are provided. One of the methods includes: generating a blockchain contract and an interface specification associated with the blockchain contract based on a plurality of first inputs; deploying the blockchain contract on a blockchain; generating a client-side application based on a plurality of second inputs and the interface specification associated with the blockchain contract, wherein the client-side application is executable to invoke the blockchain contract deployed on the blockchain; and storing the client-side application in an online storage system.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for implementing a blockchain-based decentralized application, are provided. One of the methods includes: generating a request to an external service based on a software development kit (SDK) associated with the external service, wherein the SDK is integrated with a client-side application on the client device; sending the request to a server associated with the external service; obtaining, from the server associated with the external service, a result responsive to the request; generating a blockchain transaction based on the result from the external service, wherein the blockchain transaction invokes a blockchain contract deployed on a blockchain; sending the blockchain transaction to one or more blockchain nodes for adding to the blockchain; and obtaining, from one or more data stores synchronized with the blockchain, one or more return values associated with adding the blockchain transaction to the blockchain.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based data synchronization, are provided. One of the methods includes: obtaining, from one or more blockchain nodes associated with a blockchain, data associated with a plurality of blockchain transactions recorded in one or more blocks of the blockchain; storing the obtained data in one or more data stores, wherein the storing comprises organizing the obtained data according to one or more schemas, at least one of the one or more schemas being different from a data structure of the blockchain; receiving, from a client device, a data query based on one of the one or more schemas; executing the data query on the data in the one or more data stores to obtain a result; and sending, to the client device, a response comprising the obtained result.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based decentralized application development, are provided. One of the methods includes: generating a blockchain contract and an interface specification associated with the blockchain contract based on a plurality of first inputs; deploying the blockchain contract on a blockchain; generating a client-side application based on a plurality of second inputs and the interface specification associated with the blockchain contract, wherein the client-side application is executable to invoke the blockchain contract deployed on the blockchain; and storing the client-side application in an online storage system.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for implementing a blockchain-based workflow. One of the methods includes maintaining data identifying one or more states recorded in a blockchain network as triggering states of one or more client service methods to be executed by one or more client devices off the blockchain network participating in a workflow; receiving, from a first client device, a request for executing a transaction on a blockchain network; instructing the blockchain network to execute the transaction; monitoring, by the network server, a state on the blockchain network after execution of the transaction; identifying the state to be a triggering state of a client service method of a second client device participating in the workflow; and sending, to the second client device, a notification that the triggering state is reached.

Abstract: Disclosed herein are methods, systems, and apparatus, including computer programs encoded on computer storage media, for implementing a blockchain-based workflow. One of the methods includes receiving a workflow specification that indicates one or more state transition methods to be performed by a smart contract on a blockchain network and one or more client service methods to be performed by one or more client devices off the blockchain network participating in a workflow. The smart contract is generated according to the workflow specification and includes the one or more state transition methods. A configurable client service logic is generated according to the workflow specification for each of the one or more client devices and includes the one or more client service methods. The smart contract is deployed to the blockchain network.