I’m trying to write an add-on over the swagger-ui image, so that when a container is deployed, it goes to the specified addresses of other containers and aggregates them with swagger.json into one common one, which is then passed to swagger-ui. At the moment, I have written a script in C# that successfully aggregates json, but I can’t get it to pass to swagger.
C#:

using Newtonsoft.Json.Linq;
using System;
using System.IO;
using System.Net;
using System.Text;

namespace SwaggerConfigGeneration
{
    internal class Program
    {
        private const string startJSON = @"{
  ""openapi"": ""3.0.1"",
  ""info"": {
    ""title"": ""TestApi"",
    ""version"": ""1.0""
  },
  ""paths"": {";
        private const string endJSON = @"},
  ""components"": { }
}";

        static void Main(string[] args)
        {
            StringBuilder sb = new StringBuilder(
                startJSON);

            var swaggerServises = (Environment
                .GetEnvironmentVariable("SWAGGER_SERVISES") ?? "localhost")
                .Replace(" ", "")
                .Replace("n", "")
                .Split(',');
            try
            {
                foreach (var servis in swaggerServises)
                {
                    var json = GetSwaggerServisJson(servis);

                    sb.Append(json["paths"].ToString()[1..^2]);
                    sb.Append(',');
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());
            }
            sb.Remove(sb.Length-1,1);
            sb.Append(endJSON);
            using (FileStream fstream = new FileStream("swagger.json", FileMode.Create))
            {
                var buf = Encoding.Default.GetBytes(sb.ToString());
                fstream.WriteAsync(buf, 0, buf.Length);
            }
            Console.WriteLine("Произведенно получение данных API");
        }
        private static JObject GetSwaggerServisJson(string swaggerServis)
        {
            using (WebClient wc = new WebClient())
            {
                var json = wc.DownloadString($"http://{swaggerServis}:8080/swagger/v1/swagger.json");
                return JObject.Parse(json);
            }
        }
    }
}

dockerfile:

WORKDIR /app
ENV SWAGGER_SERVISES = localhost
COPY /bin/Debug/net8.0 /app
RUN dotnet SwaggerConfigGeneration.dll

FROM swaggerapi/swagger-ui
COPY --from=builder /app/swagger.json /app/swagger.json

docker-compose.yml

version: '3'
services:
  swagger:
    image: swagger-config-generation:latest
    container_name: swagger
    environment:
      SWAGGER_SERVISES: ${SWAGGER_SERVISES}
    depends_on:
      - test-app
      - test-app2
    ports:
      - 8081:8080

  test-app:
    image: testapi:latest
    container_name: test-app
    ports: 
      - 8080:8080

  test-app2:
    image: testapi2:latest
    container_name: test-app2
    ports:
      - 8082:8080

.env:

SWAGGER_SERVISES = test-app2, test-app