Microsoft graph batch inserting new task and updating details - odata

Question

Current steps for creating task are
POST /planner/tasks
GET /planner/tasks/{id from post call}/details
PATCH /planner/tasks/{id from post call}/details
If-Match: {etag from get call}
but I want to batch three steps in single call using https://developer.microsoft.com/en-us/graph/docs/concepts/json_batching
And according to odata v4 references http://docs.oasis-open.org/odata/odata-json-format/v4.01/csprd02/odata-json-format-v4.01-csprd02.html#sec_ReferencingNewEntities we can refer entities in same batch call using ${id of other request}
{
"requests": [
{
"id": "task",
"url": "/planner/tasks",
"body": {
"title": "asff",
"appliedCategories": {
"category5": true
},
"planId": "mSV7ODf3g0iTJrUtsNcvHZYAB-ZW",
"bucketId": "WFN6kxMykE-4xxqLUh1uS5YALCWq",
"assignments": {
"4393baf8-8a52-4164-bf93-b1cba5130329": {
"#odata.type": "#microsoft.graph.plannerAssignment",
"orderHint": " !"
}
},
"dueDateTime": "2018-04-23T18:30:00.000Z"
},
"method": "POST",
"headers": {
"Content-Type": "application/json"
}
},
{
"id": "getDetail",
"method": "GET",
"dependsOn": [
"task"
],
"url": "/planner/tasks/$task/details"
},
{
"id": "patchDetail",
"dependsOn": [
"getDetail"
],
"url": "/planner/tasks/$task/details",
"method": "PATCH",
"headers": {
"Content-Type": "application/json",
"if-match": "$getDetail"
},
"body": {
"description": "gwrthbetrhnety"
}
}
}
]
}
but Get details call is failing with error
{
"id": "getDetail",
"status": 400,
"body": {
"error": {
"code": "BadRequest",
"message": "The request URI is not valid. Since the segment 'tasks' refers to a collection, this must be the last segment in the request URI or it must be followed by an function or action that can be bound to it otherwise all intermediate segments must refer to a single resource.",
"innerError": {
"request-id": "a46ce528-993f-4cff-865e-98b2b98d5f23",
"date": "2018-04-17T10:38:29"
}
}
}
}
What I'm doing wrong here

Answer 1

I believe what is missing is the URI (should be POST https://graph.microsoft.com/v1.0/$batch instead of POST /planner/tasks) and "id" field has to be numeric. Check out MS documentation:
https://learn.microsoft.com/en-us/graph/json-batching?context=graph%2Fapi%2F1.0&view=graph-rest-1.0
Here is an example of combining POST and GET in a batch call