适配Fabric¶

WeEvent支持区块链Fabric 1.4。以下安装以CentOS 7.2为例。

前置条件¶

安装weevent-broker, 具体安装步骤weevent-broker章节

以weevent-broker安装到 /usr/local/weevent/weevent-broker-1.3.0 目录为例。
安装Fabric 1.4区块链节点(以官网Fabric Samples安装为例),

具体安装步骤, 请参见Fabric安装。

以Fabric 1.4安装到 /usr/local/fabric/fabric-sample 目录为例。

修改Fabric的配置文件¶

配置Fabric节点的证书文件
- 配置WeEvent访问区块链
```
$ cd /usr/local/weevent/weevent-broker-1.3.0/
$ vi ./conf/weevent.properties
```
  修改broker.blockchain.type配置项为：broker.blockchain.type=fabric。
- 配置证书文件
  
  将Fabric目录/usr/local/fabric/fabric-sample/first-network/crypto-config/所有文件，
  
  拷贝到weevent-broker安装目录下/conf/fabric/crypto-config/里。
- 区块链节点配置文件fabric.properties
```
$ vi ./conf/fabric/fabric.properties
```
  - 修改配置项
```
chain.organizations.user.keyfile=fabric/crypto-config/peerOrganizations/org1.example.com/users/Admin@org1.example.com/msp/keystore/xxx_sk
chain.peer.address=127.0.0.1:7051
chain.orderer.address=127.0.0.1:7050
```
  替换127.0.0.1为部署Fabric节点的ip (peer端口默认为7051,orderer端口默认为7050)

部署系统合约

运行脚本./deploy-fabric-topic-control.sh部署合约。例如:

$ ./deploy-fabric-topic-control.sh deploy
begin deploy topic and topicController contract.
begin add topic into topicController contract.
deploy contract success. 

重启服务¶

停止服务

$ ./broker.sh stop
stop broker success
remove the crontab job success

启动服务

$ ./broker.sh start
start broker success (PID=89054)
add the crontab job success

RESTful请求样例¶

创建Topic,发布事件

$ curl "http://localhost:8080/weevent/rest/open?topic=com.weevent.test&groupId=mychannel"
[1] 16414
$ true
$ curl "http://localhost:8080/weevent/rest/publish?topic=com.weevent.test&groupId=mychannel&content=123456&weevent-format=json"
$ {"status":"SUCCESS","topic":"com.weevent.test","eventId":"317e7c4c-301009-6705"}

代码样例¶

API里所有的groupId就是Fabric的channelname, 以发布事件为例：

public class Rest {
    public static void main(String[] args) {
        System.out.println("This is WeEvent restful sample.");
        try {
            SimpleClientHttpRequestFactory requestFactory = new SimpleClientHttpRequestFactory();
            RestTemplate rest = new RestTemplate(requestFactory);

            // ensure topic exist "com.weevent.test"
            String topic = "com.weevent.test";
            ResponseEntity<BaseResponse<Boolean>> rsp = rest.exchange("http://localhost:7000/weevent-broker/rest/open?topic={topic}&groupId={groupId}", HttpMethod.GET, null, new ParameterizedTypeReference<BaseResponse<Boolean>>() {
            }, topic, "mychannel");

            System.out.println(rsp.getBody().getData());
            // publish event to topic "com.weevent.test"
            SendResult sendResult = rest.getForEntity("http://localhost:8080/weevent/rest/publish?topic={topic}&groupId={groupId}&content={content}",
                    SendResult.class,
                    topic,
                    "mychannel",
                    "hello weevent".getBytes(StandardCharsets.UTF_8)).getBody();
            System.out.println(sendResult.getStatus());
            System.out.println(sendResult.getEventId());
        } catch (RestClientException e) {
            e.printStackTrace();
        }
    }
}