如何使用 Rally REST .NET 将附件添加到用户故事

我们正在将 .NET Rally 代码从 SOAP 移植到 REST .NET API。到目前为止，REST API 似乎更快并且更易于使用，因为每次工作产品自定义字段在 Rally 工作区中发生更改时都不会破坏 WSDL。

不过，当我们尝试复制上传附件的功能时，我遇到了一件事。我们正在遵循与这篇文章中概述的非常相似的程序：

Rally SOAP API - 如何向分层需求添加附件

由此图像被读入 System.Drawing.Image。我们使用 ImageToByteArray 函数将图像转换为字节数组，然后将其分配给首先创建的 AttachmentContent。

然后，创建附件，并将其连接到 AttachmentContent 和 HierarchicalRequirement。

所有的创作活动都进展顺利。内容对象创建得很好。然后，将创建名为“Image.png”的新附件并将其链接到故事。但是当我从 Rally 下载生成的附件时，Image.png 的字节为零！我已经用不同的图像、JPEG、PNG 等进行了尝试，结果都相同。

下面是显示我们流程的代码摘录。我是否缺少一些明显的东西？提前致谢。

    // .... Read content into a System.Drawing.Image called imageObject ....

    // Convert Image to byte array
    byte[] imageBytes = ImageToByteArray(imageObject, System.Drawing.Imaging.ImageFormat.Png);
    var imageLength = imageBytes.Length;

    // AttachmentContent
    DynamicJsonObject attachmentContent = new DynamicJsonObject();
    attachmentContent["Content"] = imageBytes ;

    CreateResult cr = restApi.Create("AttachmentContent", myAttachmentContent);
    String contentRef = cr.Reference;
    Console.WriteLine("Created: " + contentRef);

    // Set up attachment
    DynamicJsonObject newAttachment = new DynamicJsonObject();
    newAttachment["Artifact"] = story;
    newAttachment["Content"] = attachmentContent;
    newAttachment["Name"] = "Image.png";
    newAttachment["ContentType"] = "image/png";
    newAttachment["Size"] = imageLength;
    newAttachment["User"] = user;


    // Create the attachment in Rally
    cr = restApi.Create("Attachment", newAttachment);

    String attachRef = cr.Reference;
    Console.WriteLine("Created: " + attachRef);

}

public static byte[] ImageToByteArray(Image image, System.Drawing.Imaging.ImageFormat format)
{
    using (MemoryStream ms = new MemoryStream())
    {
        image.Save(ms, format);

        // Convert Image to byte[]                
        byte[] imageBytes = ms.ToArray();
        return imageBytes;
    }
}

这个问题也让我困惑了一段时间——大约一周前终于解决了。

两个观察结果：

1. 虽然 Rally 的 SOAP API 会在后台将字节数组序列化为 Base64 字符串，但 REST 不会为您执行此步骤，并且会期望将 Base64 格式的字符串作为 AttachmentContent 对象的 Content 属性传递。
2. 示例中所示的 System.Drawing.Image.Length 不会提供 Rally 的 WSAPI 期望的正确长度。您需要在转换回常规字符串后传递 Base64 格式字符串的长度。这也与字节数组的长度相同。

我提供了一个代码示例来说明：

// System Libraries
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing.Imaging;
using System.Drawing;
using System.IO;
using System.Web;

// Rally REST API Libraries
using Rally.RestApi;
using Rally.RestApi.Response;

namespace RestExample_CreateAttachment
{
    class Program
    {
        static void Main(string[] args)
        {
            // Set user parameters
            String userName = "[email protected]";
            String userPassword = "password";

            // Set Rally parameters
            String rallyURL = "https://rally1.rallydev.com";
            String rallyWSAPIVersion = "1.36";

            //Initialize the REST API
            RallyRestApi restApi;
            restApi = new RallyRestApi(userName,
                                       userPassword,
                                       rallyURL,
                                       rallyWSAPIVersion);

            // Create Request for User
            Request userRequest = new Request("user");
            userRequest.Fetch = new List<string>()
                {
                    "UserName",
                    "Subscription",
                    "DisplayName",
                };

            // Add a Query to the Request
            userRequest.Query = new Query("UserName",Query.Operator.Equals,userName);

            // Query Rally
            QueryResult queryUserResults = restApi.Query(userRequest);

            // Grab resulting User object and Ref
            DynamicJsonObject myUser = new DynamicJsonObject();
            myUser = queryUserResults.Results.First();
            String myUserRef = myUser["_ref"];

            //Set our Workspace and Project scopings
            String workspaceRef = "/workspace/12345678910";
            String projectRef = "/project/12345678911";
            bool projectScopingUp = false;
            bool projectScopingDown = true;

            // Find User Story that we want to add attachment to

            // Tee up Story Request
            Request storyRequest = new Request("hierarchicalrequirement");
            storyRequest.Workspace = workspaceRef;
            storyRequest.Project = projectRef;
            storyRequest.ProjectScopeDown = projectScopingDown;
            storyRequest.ProjectScopeUp = projectScopingUp;

            // Fields to Fetch
            storyRequest.Fetch = new List<string>()
                {
                    "Name",
                    "FormattedID"
                };

            // Add a query
            storyRequest.Query = new Query("FormattedID", Query.Operator.Equals, "US43");

            // Query Rally for the Story
            QueryResult queryResult = restApi.Query(storyRequest);

            // Pull reference off of Story fetch
            var storyObject = queryResult.Results.First();
            String storyReference = storyObject["_ref"];

            // Read In Image Content
            String imageFilePath = "C:\\Users\\username\\";
            String imageFileName = "image1.png";
            String fullImageFile = imageFilePath + imageFileName;
            Image myImage = Image.FromFile(fullImageFile);

            // Get length from Image.Length attribute - don't use this in REST though
            // REST expects the length of the image in number of bytes as converted to a byte array
            var imageFileLength = new FileInfo(fullImageFile).Length;
            Console.WriteLine("Image File Length from System.Drawing.Image: " + imageFileLength);

            // Convert Image to Base64 format
            string imageBase64String = ImageToBase64(myImage, System.Drawing.Imaging.ImageFormat.Png);           

            // Length calculated from Base64String converted back
            var imageNumberBytes = Convert.FromBase64String(imageBase64String).Length;

            // This differs from just the Length of the Base 64 String!
            Console.WriteLine("Image File Length from Convert.FromBase64String: " + imageNumberBytes);

            // DynamicJSONObject for AttachmentContent
            DynamicJsonObject myAttachmentContent = new DynamicJsonObject();
            myAttachmentContent["Content"] = imageBase64String;

            try
            {
                CreateResult myAttachmentContentCreateResult = restApi.Create("AttachmentContent", myAttachmentContent);
                String myAttachmentContentRef = myAttachmentContentCreateResult.Reference;
                Console.WriteLine("Created: " + myAttachmentContentRef);

                // DynamicJSONObject for Attachment Container
                DynamicJsonObject myAttachment = new DynamicJsonObject();
                myAttachment["Artifact"] = storyReference;
                myAttachment["Content"] = myAttachmentContentRef;
                myAttachment["Name"] = "AttachmentFromREST.png";
                myAttachment["Description"] = "Attachment Desc";
                myAttachment["ContentType"] = "image/png";
                myAttachment["Size"] = imageNumberBytes;
                myAttachment["User"] = myUserRef;

                CreateResult myAttachmentCreateResult = restApi.Create("Attachment", myAttachment);

                List<string> createErrors = myAttachmentContentCreateResult.Errors;
                for (int i = 0; i < createErrors.Count; i++)
                {
                    Console.WriteLine(createErrors[i]);
                }

                String myAttachmentRef = myAttachmentCreateResult.Reference;
                Console.WriteLine("Created: " + myAttachmentRef);

            }
            catch (Exception e)
            {
                Console.WriteLine("Unhandled exception occurred: " + e.StackTrace);
                Console.WriteLine(e.Message);
            }
        }

        // Converts image to Base 64 Encoded string
        public static string ImageToBase64(Image image, System.Drawing.Imaging.ImageFormat format)
        {
            using (MemoryStream ms = new MemoryStream())
            {
                image.Save(ms, format);
                // Convert Image to byte[]                
                byte[] imageBytes = ms.ToArray();

                // Convert byte[] to Base64 String
                string base64String = Convert.ToBase64String(imageBytes);

                return base64String;
            }
        }
    }
}