How to partially update a listing with PatchListingsItem method

[henryvuong2]

I am trying to make API calls from my C# SDK. In this program. The model I am using is listings-items-api-model. I deserialize a JSON string into C# objects and pass them as arguments into some methods to make API calls. The issue I have is the objects are not the same type with the arguments in the method signature. Below is my code. Pay attention to the "error" comments I make in the Main() method:

`/*

• Selling Partner API for Listings Items
• The Selling Partner API for Listings Items (Listings Items API) provides programmatic access to selling partner listings on Amazon. Use this API in collaboration with the Selling Partner API for Product Type Definitions, which you use to retrieve the information about Amazon product types needed to use the Listings Items API. For more information, see the Listings Items API Use Case Guide.
• OpenAPI spec version: 2021-08-01
• Generated by: https://github.com/swagger-api/swagger-codegen.git
  */

using System;
using System.IO;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Reflection;
using RestSharp;
using NUnit.Framework;
using SellingPartnerAPI.ListingsItemsAPI.Client;
using SellingPartnerAPI.ListingsItemsAPI.Api;
using SellingPartnerAPI.ListingsItemsAPI.Model;
using Amazon.SellingPartnerAPIAA;
using System.Text.RegularExpressions;
using Newtonsoft.Json;
using static SellingPartnerAPI.ListingsItemsAPI.Test.ListingsApiTests;

namespace SellingPartnerAPI.ListingsItemsAPI.Test
{
///

/// Class for testing ListingsApi
///

///
/// This file is automatically generated by Swagger Codegen.
/// Please update the test case below to test the API endpoint.
///
[TestFixture]
public class ListingsApiTests
{
private ListingsApi instance;

    /// <summary>
    /// Setup before each unit test
    /// </summary>
    [SetUp]
    public void Init()
    {
        // TODO uncomment below to initialize instance for testing
        //instance = new ListingsApi();
    }

    /// <summary>
    /// Clean up after each unit test
    /// </summary>
    [TearDown]
    public void Cleanup()
    {

    }

    /// <summary>
    /// Test an instance of ListingsApi
    /// </summary>
    [Test]
    public void InstanceTest()
    {
        // TODO uncomment below to test 'IsInstanceOfType' ListingsApi
        //Assert.IsInstanceOfType(typeof(ListingsApi), instance, "instance is a ListingsApi");
    }

    
    /// <summary>
    /// Test DeleteListingsItem
    /// </summary>
    [Test]
    public void DeleteListingsItemTest()
    {
        // TODO uncomment below to test the method and replace null with proper value
        //string sellerId = null;
        //string sku = null;
        //List<string> marketplaceIds = null;
        //string issueLocale = null;
        //var response = instance.DeleteListingsItem(sellerId, sku, marketplaceIds, issueLocale);
        //Assert.IsInstanceOf<ListingsItemSubmissionResponse> (response, "response is ListingsItemSubmissionResponse");
    }
    
    /// <summary>
    /// Test GetListingsItem
    /// </summary>
    [Test]
    public void GetListingsItemTest()
    {
        // TODO uncomment below to test the method and replace null with proper value
        //string sellerId = null;
        //string sku = null;
        //List<string> marketplaceIds = null;
        //string issueLocale = null;
        //List<string> includedData = null;
        //var response = instance.GetListingsItem(sellerId, sku, marketplaceIds, issueLocale, includedData);
        //Assert.IsInstanceOf<Item> (response, "response is Item");
    }
    
    /// <summary>
    /// Test PatchListingsItem
    /// </summary>
    [Test]
    public void PatchListingsItemTest()
    {
        // TODO uncomment below to test the method and replace null with proper value
        //string sellerId = null;
        //string sku = null;
        //List<string> marketplaceIds = null;
        //ListingsItemPatchRequest body = null;
        //string issueLocale = null;
        //var response = instance.PatchListingsItem(sellerId, sku, marketplaceIds, body, issueLocale);
        //Assert.IsInstanceOf<ListingsItemSubmissionResponse> (response, "response is ListingsItemSubmissionResponse");
    }
    
    /// <summary>
    /// Test PutListingsItem
    /// </summary>
    [Test]
    public void PutListingsItemTest()
    {
        // TODO uncomment below to test the method and replace null with proper value
        //string sellerId = null;
        //string sku = null;
        //List<string> marketplaceIds = null;
        //ListingsItemPutRequest body = null;
        //string issueLocale = null;
        //var response = instance.PutListingsItem(sellerId, sku, marketplaceIds, body, issueLocale);
        //Assert.IsInstanceOf<ListingsItemSubmissionResponse> (response, "response is ListingsItemSubmissionResponse");
    }

    //**************** Classes for Listing Item Request body *****************
    public class Root
    {
        public string productType { get; set; }
        public List<Patch> patches { get; set; }
    }
    public class Patch
    {
        public string op { get; set; }
        public string operation_type { get; set; }
        public string path { get; set; }
        public List<Value> value { get; set; }
    }
    public class Value
    {
        public string fulfillment_channel_code { get; set; }
        public int quantity { get; set; }
    }

    //Reference: https://developer-docs.amazon.com/sp-api-blog/docs/automate-your-sp-api-calls-using-the-c-sdk
    public static void Main()
    {
        try
        {
            LWAAuthorizationCredentials lwaAuthorizationCredentials = new LWAAuthorizationCredentials
            {
                ClientId = "XXXXXXXXXX",
                ClientSecret = "XXXXXXXXXX",
                RefreshToken = "XXXXXXXXXX",
                Endpoint = new Uri("https://api.amazon.com/auth/o2/token")
            };

            ListingsApi listingsApi = new ListingsApi.Builder()
                .SetLWAAuthorizationCredentials(lwaAuthorizationCredentials)
                .Build();

            string sellerId = "XXXXXXXXXX";
            List<string> marketplaceIds = new List<string>();
            marketplaceIds.Add("ATVPDKIKX0DER");
            string sku = "XXX-YYY-ZZZ";
            
            //Update qty of a single product
            //Source: https://github.com/amzn/selling-partner-api-docs/issues/2068

            string json = @"
                {
                    'productType': 'CELLULAR_PHONE',
                    'patches': [
                        {
                            'op': 'replace',
                            'operation_type': 'PARTIAL_UPDATE',
                            'path': '/attributes/fulfillment_availability',
                            'value': [
                                {
                                    'fulfillment_channel_code': 'DEFAULT',
                                    'quantity': 1
                                }
                            ]
                        }
                    ]
                }";

            var patchListing = JsonConvert.DeserializeObject<Root>(json);

            PatchOperation.OpEnum op = PatchOperation.OpEnum.Replace;
            string path = patchListing.patches[0].path;
            List<Value> value = patchListing.patches[0].value; //this value is not accepted as an argument in PatchOperation

            List<PatchOperation> patches = new List<PatchOperation>();
            patches.Add(new PatchOperation() { Op = op, Path = path, Value = value });//Error CS0029 Cannot implicitly convert type 'System.Collections.Generic.List<Value>' to 'System.Collections.Generic.List<object>'
            ListingsItemPatchRequest listingsItemPatchRequest = new ListingsItemPatchRequest(patchListing.productType, patches); 
            ListingsItemSubmissionResponse result = listingsApi.PatchListingsItem(sellerId, sku, marketplaceIds, listingsItemPatchRequest);
            Console.WriteLine(result.ToJson());
            Console.ReadLine();
        }
        catch (LWAException e)
        {
            Console.WriteLine("LWA Exception when calling SellersApi#getMarketplaceParticipations");
            Console.WriteLine(e.getErrorCode());
            Console.WriteLine(e.getErrorMessage());
            Console.WriteLine(e.Message);
        }
        catch (ApiException e)
        {
            Console.WriteLine("Exception when calling SellersApi#getMarketplaceParticipations");
            Console.WriteLine(e.Message);
        }
    }
}

}`

Here's the error (I also commented them in my code above):

Error CS1503 Argument 3: cannot convert from System.Collections.Generic.List<Value> to 'System.Collections.Generic.List<object>

The third argument of PatchOperation accepts a List<object> type, but it does not accept List<Value>. I thought "Value" is also an object?

The classes I use in the above code can be viewed here:
ListingApi.cs: https://codefile.io/f/2xeEsz3bED
ListingsItemPatchRequest.cs: https://codefile.io/f/6jn64vdcS3
PatchOperation.cs: https://codefile.io/f/07BUp2Pxdu

So the problem I have is the arguments I pass into the method are not the same type with the method's signature. How can I fixed them?

[kevnhowe]

Your patch value should be a generic object list. Here's an example of what works for me:

                ListingsApi listingsApi = new ListingsApi.Builder()
                    .SetLWAAuthorizationCredentials(lwaAuthorizationCredentials)
                    .Build();
                var patchOpType = PatchOperation.OpEnum.Replace;
                var productType = "ESSENTIAL_OIL";
                var patchPath = "/attributes/unit_count";
                var attributeValues = new
                {
                    marketplace_id = marketplaceId,
                    type = new { language_tag = "en_US", value = "Fl Oz" },
                    value = "3.38"
                };
                var patchValue = new List<object> { attributeValues };
                var patchOperation = new PatchOperation(patchOpType, patchPath, patchValue);
                var patchOperations = new List<PatchOperation>
                {
                    patchOperation
                };

[henryvuong2]

@kevnhowe
I cannot thank you enough for this. After weeks of coding and posting questions in different forums, I finally get the answer. Your code works for me, though I have to make some modification. Here's my code, just in case someone has the same question. It updates the quantity of a listing.

`public static void Main()
{
try
{
LWAAuthorizationCredentials lwaAuthorizationCredentials = new LWAAuthorizationCredentials
{
ClientId = "XXXXXXXXXX",
ClientSecret = "XXXXXXXXXX",
RefreshToken = "XXXXXXXXXX",
Endpoint = new Uri("https://api.amazon.com/auth/o2/token")
};

    ListingsApi listingsApi = new ListingsApi.Builder()
        .SetLWAAuthorizationCredentials(lwaAuthorizationCredentials)
        .Build();

    string sellerId = "XXXXXXXXXX";
    List<string> marketplaceIds = new List<string>();
    marketplaceIds.Add("XXXXXXXXXX");
    string sku = "XXX-YYY-ZZZ";

    var patchOpType = PatchOperation.OpEnum.Replace;
    var productType = "CELLULAR_PHONE";
    var patchPath = "/attributes/fulfillment_availability";
    var attributeValues = new
    {
        fulfillment_channel_code = "DEFAULT",
        quantity = 1
    };
    var patchValue = new List<object> { attributeValues };
    var patchOperation = new PatchOperation(patchOpType, patchPath, patchValue);
    var patchOperations = new List<PatchOperation>
    {
        patchOperation
    };
    ListingsItemPatchRequest listingsItemPatchRequest = new ListingsItemPatchRequest(productType, patchOperations);
    ListingsItemSubmissionResponse patcListinghResult = listingsApi.PatchListingsItem(sellerId, sku, marketplaceIds, listingsItemPatchRequest);
    Console.WriteLine(patcListinghResult.ToJson());
    //******** END Patch Listing request **********

    Console.ReadLine();
}
catch (LWAException e)
{
    Console.WriteLine("LWA Exception when calling SellersApi#getMarketplaceParticipations");
    Console.WriteLine(e.getErrorCode());
    Console.WriteLine(e.getErrorMessage());
    Console.WriteLine(e.Message);
}
catch (ApiException e)
{
    Console.WriteLine("Exception when calling SellersApi#getMarketplaceParticipations");
    Console.WriteLine(e.Message);
}

}`