如何通过VSTS REST API将工作项添加为父工作项的子项？

Alright, let's tackle this—creating a work item and linking it to a parent via the Azure DevOps (formerly VSTS) REST API is totally doable once you understand how the System.LinkTypes.Hierarchy-Reverse link type works. Here's a clear breakdown:

What is System.LinkTypes.Hierarchy-Reverse? #

First, let's demystify that link type:

• System.LinkTypes.Hierarchy is the "forward" link (used when linking a parent to a child from the parent's side)
• System.LinkTypes.Hierarchy-Reverse is the "reverse" link—this is exactly what you need when creating a new child work item and connecting it directly to an existing parent. It tells the API to establish the parent-child hierarchy from the child's perspective.

Step-by-Step Implementation #

1. Use the Correct API Endpoint #

You'll use the Create Work Item POST endpoint (adjust the API version to match your environment if needed):

POST https://dev.azure.com/{organization}/{project}/_apis/wit/workitems/${workItemType}?api-version=7.1-preview.3

Replace placeholders like {organization}, {project}, and ${workItemType} (e.g., Task, Bug) with your actual values.

2. Build the JSON Patch Request Body #

The API uses JSON Patch format to define both the work item's fields and the parent link. Here's a complete, ready-to-use example:

[
  {
    "op": "add",
    "path": "/fields/System.Title",
    "value": "New Child Task: Fix Login Button Alignment"
  },
  {
    "op": "add",
    "path": "/relations/-",
    "value": {
      "rel": "System.LinkTypes.Hierarchy-Reverse",
      "url": "https://dev.azure.com/{organization}/{project}/_apis/wit/workItems/{parentWorkItemId}",
      "attributes": {
        "comment": "Linked to parent user story via API"
      }
    }
  },
  // Add more fields here if needed
  {
    "op": "add",
    "path": "/fields/System.AssignedTo",
    "value": "Your Name"
  }
]

Key Notes on the Request: #

• The /relations/- path appends a new link to the work item's relations array (the - means "add to the end").
• The rel property must be exactly System.LinkTypes.Hierarchy-Reverse—this is non-negotiable for establishing the parent-child link.
• Replace {parentWorkItemId} with the numeric ID of your existing parent work item (e.g., a User Story or Epic).
• You can add any other standard work item fields (like description, priority) by including additional add operations in the patch array.

3. Authentication #

Don't forget to include valid authentication:

• Use a Personal Access Token (PAT) with the Work Items (Read & Write) scope. Encode your PAT in Base64 and add it to the request header:

  Authorization: Basic {base64-encoded-PAT}
  

• Alternatively, use an OAuth token if you're integrating with a service or app.

How It All Comes Together #

When you send this request:

• The API creates the new child work item with all the fields you defined.
• It automatically establishes the hierarchy link: the parent work item will show this new item as a child in its Links section, and the child work item will have its Parent field auto-populated with the parent's details.

内容的提问来源于stack exchange，提问作者Joe