Azure存储REST API响应包括XML文件开头的BOM（“）

Question

我正在为发布任务开发一个自定义vsts扩展，其中包含一个选项列表，其中包含从REST端点数据源（我的存储帐户）填充的值。我关注这个吹制链接作为参考。 https://docs.microsoft.com/en-us/vsts/extend/develop/service-endpoints?view=vsts

我上传了我的扩展程序，但选项列表中没有填充任务中的值。

以下是我所做的配置。 VSS-extension.json：

    {
  “manifestVersion”: 1,
  “id”: “build-release-task”,
  “name”: “My Custom release task”,
  “version”: “0.0.1”,
  “publisher”: “custext”,
  “public”: false,
   “targets”: [
  {
    “id”: “Microsoft.VisualStudio.Services”
  }
  ],
  “description”: “A picklist which has values populated from the REST 
   endpoint data source. Includes one build/release task.”,
   “categories”: [
   “Build and release”
  ],
  “icons”: {
  “default”: “images/extension-icon.png”
  },
  “files”: [
 {
 “path”: “buildAndReleaseTask”
    }
   ],
 “contributions”: [
   {
   “id”: “service-endpoint”,
   “description”: “Service Endpoint type for custom Storage connection”,
   “type”: “ms.vss-endpoint.service-endpoint-type”,
    “targets”: [ “ms.vss-endpoint.endpoint-types” ],
   “properties”: {
  “name”: “custom”,
  “displayName”: “Custom server connection”,
  “url”: {
   “displayName”: “Server Url”,
   “helpText”: “storage end point url.”
   },
   “dataSources”: [
   {
    “name”: “Storage Account”,
    “endpointUrl”: “{{endpoint.url}}test/?restype=container&comp=list”,
    “resultSelector”: “xpath://EnumerationResults/Blobs/Blob/Name”
     }
    ],

   ]
   }

    ],
   “helpMarkDown”: “Learn More”
   }

   },
    {
    “id”: “custom-build-release-task”,
    “type”: “ms.vss-distributed-task.task”,
    “description”: “Task with a dynamic property getting data from an 
   endpoint REST data source”,
   “targets”: [
   “ms.vss-distributed-task.tasks”
   ],
    “properties”: {
     “name”: “buildAndReleaseTask”
     }
   }
   ]

   }

task.json：

       {
        “id”: “325958a0-63b7-11e6-88a5-f7c7f66e6264”,
        “name”: “dropdownlist”,
        “friendlyName”: “Drop down list”,
        “description”: “Lists the db files”,
        “helpMarkDown”: “Custom release task.Drop down list”,
        “category”: “Utility”,
        “visibility”: [
        “Release”
        ],
      “author”: “satyam”,
      “version”: {
      “Major”: 0,
      “Minor”: 1,
      “Patch”: 0
      },
        “instanceNameFormat”: “dropdownlist $(message)”,
        “groups”: [
          {
           “name”: “advanced”,
           “displayName”: “Advanced”,
           “isExpanded”: false
         }
       ],
        “inputs”: [
           {
             “name”: “CustomService”,
              “type”: “connectedService:custom”,
              “label”: “Storage end point”,
              “defaultValue”: “”,
              “required”: true,
              “helpMarkDown”: “Select the storage account to use. If needed, 
               click on ‘manage’, and add a new Service Endpoint of type 
                 ‘Custom server connection'”
                },
             {
                 “name”: “Scripts”,
                 “type”: “pickList”,
                  “label”: “saasscripts”,
                  “required”: true,
                 “helpMarkDown”: “Select the name of the saas script.”,
                 “properties”: {
                 “EditableOptions”: “True”
                    }
                  }
                 ],
                 “dataSourceBindings”: [
                   {
                    “target”: “Scripts”,
                    “endpointId”: “$(CustomService)”,
                    “dataSourceName”: “Storage Account”
                  }
                  ],
                 “outputVariables”: [
                    {
                      “name”: “dbfile”,
                      “description”: “Application URL of the selected App 
                       Service.”
                     }
                ],
                “execution”: {
                “Node”: {
                   “target”: “powershell.js”
               }
             }
          }

endpointUrl：我尝试在数据源中的endpointUrl中使用以下方法（vss-extension.json）

？
1. {{endpoint.url}}测试/ restype =容器＆安培;可比=列表 2。https://mycontainername.blob.core.windows.net/test/restype=container&comp=list

选项列表未填充blob内容。 我猜上面的问题可能无法解析azure存储blob列表响应类型。其余的api响应包括XML文件开头的BOM（“），这可能是解析的原因。 

是否有任何方法或解决方法可以更改azure blob rest api响应以排除BOM（“）或将响应更改为JSON格式。