AutoIt
Shopify Set inventory levels to a certain amount

Use the set endpoint with the location ID and inventory item ID to set an inventory level to a specific value.
Chilkat AutoIt Downloads

AutoIt
Local $bSuccess = False

; This example requires the Chilkat API to have been previously unlocked.
; See Global Unlock Sample for sample code.

$oHttp = ObjCreate("Chilkat.Http")

$oHttp.Login = "SHOPIFY_PRIVATE_API_KEY"
$oHttp.Password = "SHOPIFY_PRIVATE_API_KEY"

; Also see: How to retrieve inventory levels

$oHttp.Accept = "application/json"

; The following JSON is sent in the request body:

; {
;   "location_id": 6884556842,
;   "inventory_item_id": 12250274365496,
;   "available": 1
; }

; Use this online tool to generate the code from sample JSON: 
; Generate Code to Create JSON

$oJsonRequestBody = ObjCreate("Chilkat.JsonObject")
$oJsonRequestBody.UpdateInt("location_id",6884556842)
$oJsonRequestBody.UpdateInt("inventory_item_id",12250274365496)
$oJsonRequestBody.UpdateInt("available",1)

Local $sUrl = "https://{shop}.myshopify.com/admin/api/2020-04/inventory_levels/set.json"

$oResp = ObjCreate("Chilkat.HttpResponse")
$bSuccess = $oHttp.HttpJson("POST",$sUrl,$oJsonRequestBody,"application/json",$oResp)
If ($bSuccess = False) Then
    ConsoleWrite($oHttp.LastErrorText & @CRLF)
    Exit
EndIf

ConsoleWrite("Response Status Code: " & $oResp.StatusCode & @CRLF)

$oJsonResponse = ObjCreate("Chilkat.JsonObject")
$oJsonResponse.Load($oResp.BodyStr)
$oJsonResponse.EmitCompact = False
ConsoleWrite($oJsonResponse.Emit() & @CRLF)

If ($oResp.StatusCode >= 300) Then
    ConsoleWrite("Failed." & @CRLF)
    Exit
EndIf

; Sample output...
; (See the parsing code below..)
; 
; Use the this online tool to generate parsing code from sample JSON: 
; Generate Parsing Code from JSON

; {
;   "inventory_level": {
;     "inventory_item_id": 12250274365496,
;     "location_id": 6884556842,
;     "available": 1,
;     "updated_at": "2018-06-26T15:44:33-04:00",
; ...
;     "admin_graphql_api_id": "gid://shopify/InventoryLevel/6485147690?inventory_item_id=12250274365496"
; ...
;   }
; }
; 

Local $inventory_levelInventory_item_id = $oJsonResponse.IntOf("inventory_level.inventory_item_id")
Local $inventory_levelLocation_id = $oJsonResponse.IntOf("inventory_level.location_id")
Local $inventory_levelAvailable = $oJsonResponse.IntOf("inventory_level.available")
Local $sInventory_levelUpdated_at = $oJsonResponse.StringOf("inventory_level.updated_at")
Local $sInventory_levelAdmin_graphql_api_id = $oJsonResponse.StringOf("inventory_level.admin_graphql_api_id")