API: ServiceHub

Within FlowLogic.call, the flow developer has access to the node’s ServiceHub, which provides access to the various services the node provides. The services offered by the ServiceHub are split into the following categories:

• ServiceHub.networkMapCache

  • Provides information on other nodes on the network (e.g. notaries…)

• ServiceHub.identityService

  • Allows you to resolve anonymous identities to well-known identities if you have the required certificates

• ServiceHub.attachments

  • Gives you access to the node’s attachments

• ServiceHub.validatedTransactions

  • Gives you access to the transactions stored in the node

• ServiceHub.vaultService

  • Stores the node’s current and historic states

• ServiceHub.keyManagementService

  • Manages signing transactions and generating fresh public keys

• ServiceHub.myInfo

  • Other information about the node

• ServiceHub.clock

  • Provides access to the node’s internal time and date

在 FlowLogic.call 中，flow 开发者能够访问节点的 ServiceHub，其提供了访问很多节点提供的服务。ServiceHub 提供的服务包括以下的类别：

• ServiceHub.networkMapCache：提供了网络中其他节点的信息（比如 notaries）
• ServiceHub.identityService：如果你有所需的认证信息，允许你将匿名的 identities 变为 well-known 的 identities
• ServiceHub.attachments：给你访问节点附件的权限
• ServiceHub.validatedTransactions：给你访问节点存储的 transactions 的权限
• ServiceHub.vaultService：存储了节点的当前和历史的 states
• ServiceHub.keyManagementService：管理签名 transactions 和生成新的公钥
• ServiceHub.myInfor：关于节点的其他信息
• ServiceHub.clock：提供访问节点的内部时间和日期

Additional, ServiceHub exposes the following properties:

• ServiceHub.loadState and ServiceHub.toStateAndRef to resolve a StateRef into a TransactionState or a StateAndRef
• ServiceHub.signInitialTransaction to sign a TransactionBuilder and convert it into a SignedTransaction
• ServiceHub.createSignature and ServiceHub.addSignature to create and add signatures to a SignedTransaction

另外，ServiceHub 暴露了以下的属性：

• ServiceHub.loadState 和 ServiceHub.toStateAndRef 来将一个 StateRef 变成一个 TransactionState 或者一个 StateAndRef
• ServiceHub.signInitialTransaction 用来给一个 TransactionBuilder 签名并且将其转换成一个 SignedTransaction
• ServiceHub.createSignature 和 ServiceHub.addSignature 用来向 SignedTransaction 创建和添加签名