# updatePurchasePack

mutation · in the family [Purchase pack](/reference/purchase-pack/)

## What it does

Edit a purchase pack — the case/pack size a vendor sells in — change its details.

Edit a PurchasePack's mutable attributes. Requires the unrestricted capability + the record's CURRENT revision.

## Careful

Edits take effect immediately and write a new revision; the old revision stays in history.

## Who may call it

Capability area: **Inventory operations** — Receiving, counting, transferring and moving stock.

- Owner
- Manager
- Associate Manager
- Warehouse Associate
- An API key whose scope allows `api:updatePurchasePack`

## Arguments

| Name | Type | Required | Notes |
| --- | --- | --- | --- |
| `id` | [ID](/types/#scalars) `ID!` | yes | The id of the record. |
| `revision` | [ID](/types/#scalars) `ID!` | yes | The revision id you read on the record; the change is refused if an edit landed in the meantime. |
| `input` | [EditPurchasePackInput](/types/EditPurchasePackInput/) `EditPurchasePackInput!` | yes | No further notes. |

## Returns

[PurchasePack](/types/PurchasePack/) `PurchasePack!` — A purchase pack — a purchasing/handling packaging definition ON a variant (case of 24, pallet of 480): NOT a UoM conversion (the inventory ledger is ALWAYS in the variant stock UoM — reaffirmed); a pack is packaging metadata + a line-ENTRY breakdown step (PO/Receipt lines entered in packs resolve to stock units at entry: packQuantity x unitsPerPack). Parent = the VARIANT (0..N packs per variant). unitsPerPack is IMMUTABLE at birth, which keeps every stored document line reconstructible forever. The code is a dup-gated LABEL (trim+case-fold vs LIVE siblings on the same variant, naming the holder — lean 1: no UNIQ marker). Live packs block the parent Variant doom (the children law); live OrgVendorItems naming a pack block ITS doom; deactivate stays FREE everywhere (an inactive pack refuses NEW line entry while its unitsPerPack keeps denominating stored terms).

## Example request

```graphql
mutation ExampleUpdatePurchasePack($id: ID!, $revision: ID!, $input: EditPurchasePackInput!) {
  updatePurchasePack(id: $id, revision: $revision, input: $input) {
    id
    sysId
    type
    caption
    status
    parentId
    rootId
    createdAt
    updatedAt
    revisionNum
    revision
    code
    unitsPerPack
    packGtin
    nominalWeightKg
    lengthCm
    widthCm
    heightCm
  }
}
```

Variables:

```json
{
  "id": "01900000-0000-7000-8000-37386ae00000",
  "revision": "01900000-0000-7000-8000-b7960e180000",
  "input": {
    "caption": "Blue jeans"
  }
}
```

Send it with the envelope naming the version: `"extensions": {"at": {"version": {"name":"genesis","number":0}}}`.

## Example response

```json
{
  "data": {
    "updatePurchasePack": {
      "id": "01900000-0000-7000-8000-37386ae00000",
      "sysId": "PK-EXMP-0000-000F",
      "type": "PurchasePack",
      "caption": "Blue jeans",
      "status": "active",
      "parentId": "01900000-0000-7000-8000-065235280000",
      "rootId": "01900000-0000-7000-8000-a093dd800000",
      "createdAt": "2027-01-31T00:00:00.000Z",
      "updatedAt": "2027-01-31T00:00:00.000Z",
      "revisionNum": 1,
      "revision": "01900000-0000-7000-8000-b7960e180000",
      "code": "BJ-001",
      "unitsPerPack": "<units per pack>",
      "packGtin": "<pack gtin>",
      "nominalWeightKg": "<nominal weight kg>",
      "lengthCm": "<length cm>",
      "widthCm": "<width cm>",
      "heightCm": "<height cm>"
    }
  },
  "extensions": {
    "at": {
      "callId": "01EXAMPLE-CALL-ID",
      "version": {
        "requested": {
          "name": "genesis",
          "number": 0
        },
        "serviced": {
          "name": "genesis",
          "number": 0
        }
      }
    }
  }
}
```

## Errors this call can answer

- `VALIDATION/INVALID` — Something in the request is not valid. ([VALIDATION](/errors/VALIDATION/))
- `AUTHN/REQUIRED` — Sign in to do this. ([AUTHN](/errors/AUTHN/))
- `AUTHZ/FORBIDDEN` — Your role does not allow this action. ([AUTHZ](/errors/AUTHZ/))
- `RATE_LIMIT/THROTTLED` — Too many requests in a short time. ([RATE_LIMIT](/errors/RATE_LIMIT/))
- `NOT_FOUND/*` — That record could not be found. ([NOT_FOUND](/errors/NOT_FOUND/))
- `CONFLICT/*` — The record’s state, or a change made in the meantime, does not allow this; the codes are on the CONFLICT page. ([CONFLICT](/errors/CONFLICT/))
- `VALIDATION/VERSION_REQUIRED` — The request did not say which app version it came from. ([VALIDATION](/errors/VALIDATION/))

## Dry run

Add `dryRun: true` to the request envelope (`extensions.at`) to rehearse this call: every check runs, the write is rehearsed against the current records and nothing is stored; the answer is the refusal a real call would give, or the record it would create. Every response to a rehearsal carries `dryRun: true`, so a rehearsed record is never mistaken for a saved one.