簡體   English   中英

等待后承諾解決但數據未定義

[英]Promise resolves after awaited but data is undefined

JavaScript 大師,我在這里錯過了什么?

簡單的測試場景如下:

   import * as request from "request-promise-native";

   export class Publisher {

        name : string = "IRocking Publisher";

        async publishAsync(): Promise<PublisherResponse> {

              var publisherResponse : PublisherResponse = PublisherResponse.EmptyResponse;

              try {

                    let response = await request.get("https://jsonplaceholder.typicode.com/todos/1");

                    console.debug("Promise has been resolved.  Result is:")
                    console.debug(response)

                    console.debug(response.userId)
                    publisherResponse = new PublisherResponse(file, this.name, true, "");
                  }
                  catch (error) {
                    publisherResponse = new PublisherResponse(file, this.name, false, error);
                 }

                return Promise.resolve<PublisherResponse>(publisherResponse); 
            }
    }

隨附 Jest 測試如下:

 test('Should publish a valid single document asynchronously', async () => {

      // Arrange

        let sut = new Publisher(); 
        let expectedResponse = new PublisherResponse(documentToPublish, sut.name, true, "");

        // Act
        let actualResponse = await sut.publishAsync(new PublicationContext(), documentToPublish);   

        // Assert
      expect(actualResponse).toEqual(expectedResponse);
      });

當我運行測試時,我看到從服務返回的數據為

 {
        "userId": 1,
        "id": 1,
        "title": "delectus aut autem",
        "completed": false
      }

但是,如果我嘗試訪問諸如“userId”之類的數據屬性,則會出現未定義的情況。 我錯過了什么?

另外,除了這個請求中的 200 之外,我如何獲得其他狀態代碼?

我需要使用反序列化從服務返回的 JSON 字符串

  var todo = JSON.parse(response);

出於某種原因,我假設響應

let response = await request.get("https://jsonplaceholder.typicode.com/todos/1");

是一個對象,但底層類型是一個string 我用以下代碼發現了這一點:

   let propertyNames = Object.keys(response);
    console.debug(propertyNames);
    propertyNames.forEach((p, i) => {
              console.debug(response[p])
            })

暫無
暫無

聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.

 
粵ICP備18138465號  © 2020-2024 STACKOOM.COM