Springcloud HRM微服务项目（三）

主要内容：

1. Fastdfs怎么和业务集成
2. 垂直分表？字段冗余？id一对一设计

一.搭建Fastdfs微服务

1.项目结构搭建

  hrm-fastdfs-parent
    	hrm-fastdfs-feign
    	hrm-fastdfs-server-2040

2.修改hrm-fastdfs-server-2040

2.1.注册到Eureka

2.2.集成Config客户端

2.3.集成Swagger

2.4.zuul配置fastdfs服务的路由

2.5.zuul整合fastdfs的swagger

2.6.集成Fastdfs实现文件上传

2.6.1.导入依赖

        <dependency>
            <groupId>org.csource</groupId>
            <artifactId>fastdfs-client-java</artifactId>
            <version>1.29-SNAPSHOT</version>
        </dependency>

2.6.2.创建配置文件fast_client.conf

#指向tracker_server所在的服务器的ip
tracker_server = fastdfs所在的服务器ip:22122

2.6.3.FastDfsApiOpr工具

package cn.myllxy.util;

import org.csource.fastdfs.ClientGlobal;
import org.csource.fastdfs.StorageClient;
import org.csource.fastdfs.StorageServer;
import org.csource.fastdfs.TrackerClient;
import org.csource.fastdfs.TrackerServer;

public class FastDfsApiOpr {

    public static String CONF_FILENAME = FastDfsApiOpr.class.getResource("/fdfs_client.conf").getFile();

    /**
     * 上传文件
     *
     * @param file
     * @param extName
     * @return
     */
    public static String upload(byte[] file, String extName) {
        try {
            ClientGlobal.init(CONF_FILENAME);
            TrackerClient tracker = new TrackerClient();
            TrackerServer trackerServer = tracker.getTrackerServer();
            StorageServer storageServer = null;
            StorageClient storageClient = new StorageClient(trackerServer, storageServer);
            String fileIds[] = storageClient.upload_file(file, extName, null);
            System.out.println(fileIds.length);
            System.out.println("组名：" + fileIds[0]);
            System.out.println("路径: " + fileIds[1]);
            return "/" + fileIds[0] + "/" + fileIds[1];

        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

2.6.4.编写文件上传Controller层方法

@RestController
@RequestMapping("/fastdfs")
public class FastdfsController {
    @PostMapping("/upload")
    public AjaxResult upload(MultipartFile file) {
        try {
            String extName = FilenameUtils.getExtension(file.getOriginalFilename());
            String filePath = FastDfsApiOpr.upload(file.getBytes(), extName);
            return AjaxResult.me().setResultObj(filePath);
        } catch (IOException e) {
            e.printStackTrace();
            return AjaxResult.me().setSuccess(false).setMessage("文件上传失败");
        }
    }
}

     	<!-- 更方便地获取文件后缀 -->
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.6</version>
        </dependency>

2.6.5.前段对接上传

                <el-upload
                        class="upload-demo"
                        action="http://localhost:1020/fastdfs/fastdfs/upload"
                        :on-preview="handlePreview"
                        :on-remove="handleRemove"
                        :on-success="handleSuccess"
                        :file-list="fileList"
                        list-type="picture">
                    <el-button size="small" type="primary">点击上传</el-button>
                    <div class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
                </el-upload>

二.课程管理

1.RedisFeign集成Hystrix

这次使用的fallbackFactory相较于fallback能够返回程序运行异常：

@FeignClient(value = "redis-server", fallbackFactory = MyFallBackFactory.class)
public interface RedisFeignClient {
    @PostMapping("/redis/set")
    AjaxResult set(@RequestParam("key") String key, @RequestParam("value") String value);

    @PostMapping("/redis/get/{key}")
    AjaxResult get(@PathVariable("key") String key);
}

@Component
public class MyFallBackFactory implements FallbackFactory<RedisFeignClient> {
    @Override
    public RedisFeignClient create(Throwable throwable) {
        return new RedisFeignClient() {
            @Override
            public AjaxResult set(String key, String value) {
                return AjaxResult.me().setSuccess(false).setMessage("Redis发生错误：" + throwable.getMessage());
            }

            @Override
            public AjaxResult get(String key) {
                return AjaxResult.me().setSuccess(false).setMessage("Redis发生错误：" + throwable.getMessage());
            }
        };
    }
}

使用如下：

        List<CourseType> courseTypes = null;
        //当调用get方法时会去redis中查对应key的数据，查不到就返回AjaxResult.me().setSuccess(false).setMessage("Redis发生错误：" + throwable.getMessage());是带有异常的
        AjaxResult ajaxResult = redisFeignClient.get(RedisKeyConstant.CPURSE_TYPE);
        if (ajaxResult.isSuccess() && null != ajaxResult.getResultObj()) {
            String jsonFromRedis = ajaxResult.getResultObj().toString();
            courseTypes = JSON.parseArray(jsonFromRedis, CourseType.class);
        } else {
            courseTypes = resetRedis();
        }

2.添加等级名字

列表中有个字段需要跨数据库查询，为了提升查询效率，我们将其写在当前表中进行查询------------字段冗余

3.完成课程添加

需要注意的是课程详情id根据课程id来(在保存课程的时候将课程id赋值给课程详情id)