1{
2  "tests": [
3    {
4      "description": "update: last-update-time precondition",
5      "comment": "The Update call supports a last-update-time precondition.",
6      "update": {
7        "docRefPath": "projects/projectID/databases/(default)/documents/C/d",
8        "precondition": {
9          "updateTime": "1970-01-01T00:00:42Z"
10        },
11        "jsonData": "{\"a\": 1}",
12        "request": {
13          "database": "projects/projectID/databases/(default)",
14          "writes": [
15            {
16              "update": {
17                "name": "projects/projectID/databases/(default)/documents/C/d",
18                "fields": {
19                  "a": {
20                    "integerValue": "1"
21                  }
22                }
23              },
24              "updateMask": {
25                "fieldPaths": [
26                  "a"
27                ]
28              },
29              "currentDocument": {
30                "updateTime": "1970-01-01T00:00:42Z"
31              }
32            }
33          ]
34        }
35      }
36    }
37  ]
38}
39