运用AI搭建中间服务层（四）

MiddlewareService文件夹

在这个文件夹中，我们需要添加以下文件：

• 名人服务.cs

• 名人服务.cs

• 名人结果.cs

• ILandmarkService.cs

• 地标服务 .cs

• 地标结果 .cs

ICelebrityService.cs – 包装多个串行的认知服务来实现名人识别的中间服务层的接口定义，需要依赖注入

using System.Threading.Tasks;namespace CognitiveMiddlewareService.MiddlewareService
{public interface ICelebrityService{Task<CelebrityResult> Do(byte[] imgData);}
}

CelebrityService.cs – 包装多个串行的认知服务来实现名人识别中间服务层的逻辑代码

using CognitiveMiddlewareService.CognitiveServices;
using Newtonsoft.Json;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.MiddlewareService
{public class CelebrityService : ICelebrityService{private readonly IVisionService visionService;private readonly IEntitySearchService entityService;public CelebrityService(IVisionService vs, IEntitySearchService ess){this.visionService = vs;this.entityService = ess;}public async Task<CelebrityResult> Do(byte[] imgData){// get original recognized resultvar stream = Helper.GetStream(imgData);Celebrity celebrity = await this.visionService.RecognizeCelebrityAsync(stream);if (celebrity != null){// get entity search resultstring entityName = celebrity.name;string jsonResult = await this.entityService.SearchEntityAsync(entityName);EntityResult er = JsonConvert.DeserializeObject<EntityResult>(jsonResult);if (er?.entities?.value.Length > 0){// isolation layer: decouple data structure then return abstract resultCelebrityResult cr = new CelebrityResult(){Name = er.entities.value[0].name,Description = er.entities.value[0].description,Url = er.entities.value[0].url,ThumbnailUrl = er.entities.value[0].image.thumbnailUrl,Confidence = celebrity.confidence};return cr;}}return null;}}
}

小提示：上面的代码中，用CelebrityResult接管了实体搜索结果和名人识别结果的部分有效字段，以达到解耦/隔离的作用，后面的代码只关心CelebrityResult如何定义的即可。

CelebrityResult.cs – 抽象出来的名人识别服务的返回结果

namespace CognitiveMiddlewareService.MiddlewareService
{public class CelebrityResult{public string Name { get; set; }public double Confidence { get; set; }public string Url { get; set; }public string Description { get; set; }public string ThumbnailUrl { get; set; }}
}

ILandmarkService.cs – 包装多个串行的认知服务来实现地标识别的中间服务层的接口定义，需要依赖注入

using CognitiveMiddlewareService.CognitiveServices;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.MiddlewareService
{public interface ILandmarkService{Task<LandmarkResult> Do(byte[] imgData);}
}

LandmarkService.cs – 包装多个串行的认知服务来实现地标识别的中间服务层的逻辑代码

using CognitiveMiddlewareService.CognitiveServices;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.MiddlewareService
{public class LandmarkService : ILandmarkService{private readonly IVisionService visionService;private readonly IEntitySearchService entityService;public LandmarkService(IVisionService vs, IEntitySearchService ess){this.visionService = vs;this.entityService = ess;}public async Task<LandmarkResult> Do(byte[] imgData){// get original recognized resultvar streamLandmark = Helper.GetStream(imgData);Landmark landmark = await this.visionService.RecognizeLandmarkAsync(streamLandmark);if (landmark != null){// get entity search resultstring entityName = landmark.name;string jsonResult = await this.entityService.SearchEntityAsync(entityName);EntityResult er = JsonConvert.DeserializeObject<EntityResult>(jsonResult);// isolation layer: decouple data structure then return abstract resultLandmarkResult lr = new LandmarkResult(){Name = er.entities.value[0].name,Description = er.entities.value[0].description,Url = er.entities.value[0].url,ThumbnailUrl = er.entities.value[0].image.thumbnailUrl,Confidence = landmark.confidence};return lr;}return null;}}
}

小提示：上面的代码中，用LandmarkResult接管了实体搜索结果和地标识别结果的部分有效字段，以达到解耦/隔离的作用，后面的代码只关心LandmarkResult如何定义的即可。

LandmarkResult.cs – 抽象出来的地标识别服务的返回结果

namespace CognitiveMiddlewareService.MiddlewareService
{public class LandmarkResult{public string Name { get; set; }public double Confidence { get; set; }public string Url { get; set; }public string Description { get; set; }public string ThumbnailUrl { get; set; }}
}

Processors文件夹

在这个文件夹中，我们需要添加以下文件：

• IProcessService.cs

• 进程服务 .cs

• 聚合结果.cs

IProcessService.cs – 任务调度层服务的接口定义，需要依赖注入

using System.Threading.Tasks;namespace CognitiveMiddlewareService.Processors
{public interface IProcessService{Task<AggregatedResult> Process(byte[] imgData);}
}

ProcessService.cs – 任务调度层服务的逻辑代码

using CognitiveMiddlewareService.MiddlewareService;
using System.Collections.Generic;
using System.Threading.Tasks;namespace CognitiveMiddlewareService.Processors
{public class ProcessService : IProcessService{private readonly ILandmarkService landmarkService;private readonly ICelebrityService celebrityService;public ProcessService(ILandmarkService ls, ICelebrityService cs){this.landmarkService = ls;this.celebrityService = cs;}public async Task<AggregatedResult> Process(byte[] imgData){// preprocess// todo: create screening image classifier to get a rough category, then decide call which service// task dispatcher: parallelized run 'Do'// todo: put this logic into Dispatcher serviceList<Task> listTask = new List<Task>();var taskLandmark = this.landmarkService.Do(imgData);listTask.Add(taskLandmark);var taskCelebrity = this.celebrityService.Do(imgData);listTask.Add(taskCelebrity);await Task.WhenAll(listTask);LandmarkResult lmResult = taskLandmark.Result;CelebrityResult cbResult = taskCelebrity.Result;// aggregator// todo: put this logic into Aggregator serviceAggregatedResult ar = new AggregatedResult(){Landmark = lmResult,Celebrity = cbResult};return ar;// ranker// todo: if there have more than one result in AgregatedResult, need give them a ranking// output generator// todo: generate specified JSON data, such as Adptive Card}}
}

小提示：大家可以看到上面这个文件中有很多绿色的注释，带有todo文字的，对于一个更复杂的系统，可以用这些todo中的描述来设计独立的模块。

AggregatedResult.cs – 任务调度层服务的最终聚合结果定义

using CognitiveMiddlewareService.MiddlewareService;namespace CognitiveMiddlewareService.Processors
{public class AggregatedResult{public LandmarkResult Landmark { get; set; }public CelebrityResult Celebrity { get; set; }}
}