How to get eBay's BulkMigrateListing() API call to work - ebay-api

Question

I'm trying to migrate an eBay listing over to eBay MIP NG by using the call BulkMigrateListing using PostMan.
From PostMan the C# call is:
var client = new RestClient("https://api.ebay.com/sell/inventory/v1/bulk_migrate_listing");
var request = new RestRequest(Method.POST);
request.AddHeader("Postman-Token", "c6a6a651-6412-4fc6-94fb-4459883e69e5");
request.AddHeader("Cache-Control", "no-cache");
request.AddHeader("Authorization", "Bearer The-User-OAuth-Token");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("undefined", "JSON-String", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
where JSON-String is:
{
"requests" :
[
{ "listingId" : "123456...." }
]
}
and The-User-OAuth-Token is the token from the eBay developer account suitably authorised.
But the response I get in PostMan is:
{
"errors": [
{
"errorId": 25001,
"domain": "API_INVENTORY",
"subdomain": "Selling",
"category": "SYSTEM",
"message": "A system error has occurred."
}
]
}
Has anyone successfully made a call to BulkMigrateListing? What am I doing wrong?

Answer 1

Here's what I've found so far:
BulkMigrateListing() is very flakey. From experience, the response.Content might be
1. {"errors":[{"errorId":25001,"domain":"API_INVENTORY","subdomain":"Selling","category":"SYSTEM","message":"A system error has occurred."}]}
2. {"errors":[{"errorId": 1001,"domain": "OAuth","category": "REQUEST","message": "Invalid access token","longMessage": "Invalid access token. Check the value of the Authorization HTTP request header."}]}
3. Missing token message
4. {"responses": [{"statusCode": 200,"listingId": "123412958208","marketplaceId": "EBAY_DE","inventoryItems": [{"sku": "ABC-004","offerId": "12347167010"}]}]}
If the call works then #4 or #1 is returned.
One way to check is to call https://api.ebay.com/sell/inventory/v1/inventory_item/THE-USER-SKU.
Returning data might be:
1. {"sku": "ABC-003","product": {"title":"The Royal Wedding Harry & Meghan Commemorative Flag With Grommets 52\" x 31\"","aspects": {"Brand": ["PMS"],"Type": [.......
2. {"errors": [{"errorId": 25710,"domain": "API_INVENTORY","subdomain": "Selling","category": "REQUEST","message": "We didn't find the entity you are requesting. Please verify the request"}
If the product has been migrated over to MIP NG then #1 is returned otherwise it's #2.