Fabric（v2.0）官方文档-超级账本Fabric智能合约（链码）APIs & 应用SDKs

APIs

Hyperledger Fabric提供了许多api来支持使用多种编程语言发智能契约(chaincode)。智能合约APIs可用于Go, Node.js和Java。

• Go contract-api.
• Node.js contract API and Node.js contract API documentation.
• Java contract API and Java contract API documentation.

有关智能合约的概念及编程模型的详细解释，请参阅Chaincode Tutorials section of the Hyperledger Fabric documentation.

有关商业票据和fabcar的Java链码样本，请参阅fabric-samples repository

Java 链码 maven：

  org.hyperledger.fabric-chaincode-java
  fabric-chaincode-shim
  VERSION

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SDKs

Fabric Gateway SDK允许应用程序与Fabric区块链网络进行交互。它提供了一个简单的API，可以用最少的代码向分类帐提交事务或查询分类帐的内容。

用法

下面展示了如何使用实例化的smart contract (fabcar示例)连接到fabric网络、提交事务和查询分类帐状态的完整代码示例。

import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.concurrent.TimeoutException;

import org.hyperledger.fabric.gateway.Contract;
import org.hyperledger.fabric.gateway.ContractException;
import org.hyperledger.fabric.gateway.Gateway;
import org.hyperledger.fabric.gateway.Network;
import org.hyperledger.fabric.gateway.Wallet;
import org.hyperledger.fabric.gateway.Wallets;

class Sample {
    public static void main(String[] args) throws IOException {
        // Load an existing wallet holding identities used to access the network.
        Path walletDirectory = Paths.get("wallet");
        Wallet wallet = Wallets.newFileSystemWallet(walletDirectory);

        // Path to a common connection profile describing the network.
        Path networkConfigFile = Paths.get("connection.json");

        // Configure the gateway connection used to access the network.
        Gateway.Builder builder = Gateway.createBuilder()
                .identity(wallet, "user1")
                .networkConfig(networkConfigFile);

        // Create a gateway connection
        try (Gateway gateway = builder.connect()) {

            // Obtain a smart contract deployed on the network.
            Network network = gateway.getNetwork("mychannel");
            Contract contract = network.getContract("fabcar");

            // Submit transactions that store state to the ledger.
            byte[] createCarResult = contract.createTransaction("createCar")
                    .submit("CAR10", "VW", "Polo", "Grey", "Mary");
            System.out.println(new String(createCarResult, StandardCharsets.UTF_8));

            // Evaluate transactions that query state from the ledger.
            byte[] queryAllCarsResult = contract.evaluateTransaction("queryAllCars");
            System.out.println(new String(queryAllCarsResult, StandardCharsets.UTF_8));

        } catch (ContractException | TimeoutException | InterruptedException e) {
            e.printStackTrace();
        }
    }
}

API文档

• 2.0
• 1.4

Maven

  org.hyperledger.fabric
  fabric-gateway-java
  2.0.0

 

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下载二进制文件和docker文件可以通过scripts/bootstrap.sh，你也可以下载脚本并在本地执行:

# Fetch bootstrap.sh from fabric repository using
curl -sS https://raw.githubusercontent.com/hyperledger/fabric/master/scripts/bootstrap.sh -o ./scripts/bootstrap.sh
# Change file mode to executable
chmod +x ./scripts/bootstrap.sh
# Download binaries and docker images
./scripts/bootstrap.sh [version] [ca version] [thirdparty_version]