diff --git a/ParkingLotApi.sln b/ParkingLotApi.sln
index 276b612..6a57d42 100644
--- a/ParkingLotApi.sln
+++ b/ParkingLotApi.sln
@@ -3,9 +3,9 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.7.34221.43
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ParkingLotApi", "ParkingLotApi\ParkingLotApi.csproj", "{245411D4-F8E0-4BE6-AF4C-B4EB3AC0ABBE}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ParkingLotApi", "ParkingLotApi\ParkingLotApi.csproj", "{245411D4-F8E0-4BE6-AF4C-B4EB3AC0ABBE}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ParkingLotApiTest", "ParkingLotApiTest\ParkingLotApiTest.csproj", "{3C240C7A-4F4C-42B9-91A1-DE41AAB75DAE}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "ParkingLotApiTest", "ParkingLotApiTest\ParkingLotApiTest.csproj", "{3C240C7A-4F4C-42B9-91A1-DE41AAB75DAE}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
diff --git a/ParkingLotApi/Controllers/ParkingLotsController.cs b/ParkingLotApi/Controllers/ParkingLotsController.cs
new file mode 100644
index 0000000..a649994
--- /dev/null
+++ b/ParkingLotApi/Controllers/ParkingLotsController.cs
@@ -0,0 +1,70 @@
+using Microsoft.AspNetCore.Mvc;
+using ParkingLotApi.Exceptions;
+using ParkingLotApi.Models;
+using ParkingLotApi.Services;
+
+namespace ParkingLotApi.Controllers
+{
+    [ApiController]
+    [Route("api/[controller]")]
+    public class ParkingLotsController : ControllerBase
+    {
+        private readonly ParkingLotsService _parkingLotsService;
+        public ParkingLotsController(ParkingLotsService parkingLotsService)
+        {
+            _parkingLotsService = parkingLotsService;
+        }
+
+        [HttpPost]
+        public async Task<ActionResult<ParkingLotEntity>> AddParkingLot([FromBody] ParkingLotDto parkingLotDto)
+        {
+           /* try
+            {*/
+               // return  Created("", await _parkingLotsService.AddAsync(parkingLotDto));
+                return StatusCode(StatusCodes.Status201Created, await _parkingLotsService.AddAsync(parkingLotDto));
+           /* } catch (InvalidCapacityException ex)
+            {
+                return BadRequest(ex.Message);
+            }*/
+        }
+
+        [HttpDelete("{id}")]
+        public async Task<ActionResult> RemoveParkingLot(string id)
+        {
+            var isRemoved = await _parkingLotsService.RemoveAsync(id);
+            if (isRemoved) 
+            { 
+                return NoContent();
+            }
+            return NotFound();
+        }
+
+        [HttpGet]
+        public async Task<ActionResult<List<ParkingLotEntity>>> GetOnePageParkingLots([FromQuery] int pageIndex)
+        {
+            return await _parkingLotsService.GetOnePageParkingLots(pageIndex);
+        }
+
+        [HttpGet("{id}")]
+        public async Task<ActionResult<List<ParkingLotEntity>>> GetParkingLotById(string id)
+        {
+            var parkingLot = await _parkingLotsService.GetByIdAsync(id);
+            if (parkingLot == null)
+            {
+                return NotFound();
+            }
+            return Ok(parkingLot);
+        }
+
+        [HttpPut("{id}")]
+        public async Task<ActionResult<ParkingLotEntity>> UpdateCapacityAsync(string id, [FromBody] int capacity)
+        {
+            var updatedParkingLot = await _parkingLotsService.UpdateCapacity(id, capacity);
+            if (updatedParkingLot == null)
+            {
+                return NotFound();
+            }
+            return Ok(updatedParkingLot);
+        }
+    }
+}
\ No newline at end of file
diff --git a/ParkingLotApi/Controllers/WeatherForecastController.cs b/ParkingLotApi/Controllers/WeatherForecastController.cs
deleted file mode 100644
index e0bef6b..0000000
--- a/ParkingLotApi/Controllers/WeatherForecastController.cs
+++ /dev/null
@@ -1,33 +0,0 @@
-using Microsoft.AspNetCore.Mvc;
-
-namespace ParkingLotApi.Controllers
-{
-    [ApiController]
-    [Route("[controller]")]
-    public class WeatherForecastController : ControllerBase
-    {
-        private static readonly string[] Summaries = new[]
-        {
-        "Freezing", "Bracing", "Chilly", "Cool", "Mild", "Warm", "Balmy", "Hot", "Sweltering", "Scorching"
-    };
-
-        private readonly ILogger<WeatherForecastController> _logger;
-
-        public WeatherForecastController(ILogger<WeatherForecastController> logger)
-        {
-            _logger = logger;
-        }
-
-        [HttpGet(Name = "GetWeatherForecast")]
-        public IEnumerable<WeatherForecast> Get()
-        {
-            return Enumerable.Range(1, 5).Select(index => new WeatherForecast
-            {
-                Date = DateOnly.FromDateTime(DateTime.Now.AddDays(index)),
-                TemperatureC = Random.Shared.Next(-20, 55),
-                Summary = Summaries[Random.Shared.Next(Summaries.Length)]
-            })
-            .ToArray();
-        }
-    }
-}
\ No newline at end of file
diff --git a/ParkingLotApi/Dtos/ParkingLotDto.cs b/ParkingLotApi/Dtos/ParkingLotDto.cs
new file mode 100644
index 0000000..d788dcf
--- /dev/null
+++ b/ParkingLotApi/Dtos/ParkingLotDto.cs
@@ -0,0 +1,14 @@
+namespace ParkingLotApi.Models
+{
+    public class ParkingLotDto
+    {
+        public string Name { get; set; }
+        public int Capacity { get; set; }
+        public string Location { get; set; }
+
+        internal ParkingLotEntity ToEntity()
+        {
+            return new ParkingLotEntity { Name = Name, Capacity = Capacity, Location = Location };
+        }
+    }
+}
diff --git a/ParkingLotApi/Exceptions/InvalidCapacityException.cs b/ParkingLotApi/Exceptions/InvalidCapacityException.cs
new file mode 100644
index 0000000..f2bf25c
--- /dev/null
+++ b/ParkingLotApi/Exceptions/InvalidCapacityException.cs
@@ -0,0 +1,10 @@
+namespace ParkingLotApi.Exceptions
+{
+    public class InvalidCapacityException : Exception
+    {
+        public InvalidCapacityException(string message) : base(message) 
+        {
+        
+        }
+    }
+}
diff --git a/ParkingLotApi/Filters/InvalidCapacityExceptionFilter.cs b/ParkingLotApi/Filters/InvalidCapacityExceptionFilter.cs
new file mode 100644
index 0000000..efb59ae
--- /dev/null
+++ b/ParkingLotApi/Filters/InvalidCapacityExceptionFilter.cs
@@ -0,0 +1,25 @@
+using Microsoft.AspNetCore.Http.HttpResults;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.Filters;
+using ParkingLotApi.Exceptions;
+
+namespace ParkingLotApi.Filters
+{
+    public class InvalidCapacityExceptionFilter : IActionFilter, IOrderedFilter
+    {
+        public int Order => int.MaxValue - 10;
+
+        public void OnActionExecuted(ActionExecutedContext context)
+        {
+            if (context.Exception is InvalidCapacityException invalidCapacityException)
+            {
+                context.Result = new BadRequestResult();
+                context.ExceptionHandled = true;
+            }
+        }
+
+        public void OnActionExecuting(ActionExecutingContext context)
+        {
+        }
+    }
+}
diff --git a/ParkingLotApi/Models/ParkingLotEntity.cs b/ParkingLotApi/Models/ParkingLotEntity.cs
new file mode 100644
index 0000000..f9a0e35
--- /dev/null
+++ b/ParkingLotApi/Models/ParkingLotEntity.cs
@@ -0,0 +1,16 @@
+using MongoDB.Bson;
+using MongoDB.Bson.Serialization.Attributes;
+
+namespace ParkingLotApi.Models
+{
+    public class ParkingLotEntity
+    {
+        [BsonId]
+        [BsonRepresentation(BsonType.ObjectId)]
+        public string? Id { get; set; }
+
+        public string Name { get; set; }
+        public int Capacity { get; set; }
+        public string Location { get; set; }
+    }
+}
diff --git a/ParkingLotApi/Models/ParkingLotsDatabaseSettings.cs b/ParkingLotApi/Models/ParkingLotsDatabaseSettings.cs
new file mode 100644
index 0000000..edecc1e
--- /dev/null
+++ b/ParkingLotApi/Models/ParkingLotsDatabaseSettings.cs
@@ -0,0 +1,9 @@
+namespace ParkingLotApi.Models
+{
+    public class ParkingLotsDatabaseSettings
+    {
+        public string ConnectionString { get; set; } = null!;
+        public string DatabaseName { get; set; } = null!;
+        public string CollectionName { get; set; } = null!;
+    }
+}
diff --git a/ParkingLotApi/ParkingLotApi.csproj b/ParkingLotApi/ParkingLotApi.csproj
index 6968690..1ebd9a5 100644
--- a/ParkingLotApi/ParkingLotApi.csproj
+++ b/ParkingLotApi/ParkingLotApi.csproj
@@ -8,6 +8,8 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="7.0.13" />
+    <PackageReference Include="MongoDB.Bson" Version="2.22.0" />
+    <PackageReference Include="MongoDB.Driver" Version="2.22.0" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
   </ItemGroup>
 
diff --git a/ParkingLotApi/Program.cs b/ParkingLotApi/Program.cs
index 8264bac..2fb01b7 100644
--- a/ParkingLotApi/Program.cs
+++ b/ParkingLotApi/Program.cs
@@ -1,12 +1,26 @@
+using ParkingLotApi.Filters;
+using ParkingLotApi.Models;
+using ParkingLotApi.Repositories;
+using ParkingLotApi.Services;
+
 var builder = WebApplication.CreateBuilder(args);
 
 // Add services to the container.
 
-builder.Services.AddControllers();
+builder.Services.AddControllers(options =>
+{
+    options.Filters.Add<InvalidCapacityExceptionFilter>();
+});
 // Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
 builder.Services.AddEndpointsApiExplorer();
 builder.Services.AddSwaggerGen();
 
+builder.Services.AddScoped<ParkingLotsService>();
+builder.Services.AddSingleton<IParkingLotsRepository, ParkingLotsRepository>();
+builder.Services.Configure<ParkingLotsDatabaseSettings>(
+    builder.Configuration.GetSection("ParkingLotsDatabase")
+);
+
 var app = builder.Build();
 
 // Configure the HTTP request pipeline.
@@ -22,4 +36,9 @@
 
 app.MapControllers();
 
-app.Run();
\ No newline at end of file
+app.Run();
+
+public partial class Program
+{
+
+}
\ No newline at end of file
diff --git a/ParkingLotApi/Repositories/IParkingLotsRepository.cs b/ParkingLotApi/Repositories/IParkingLotsRepository.cs
new file mode 100644
index 0000000..ec7f0fc
--- /dev/null
+++ b/ParkingLotApi/Repositories/IParkingLotsRepository.cs
@@ -0,0 +1,13 @@
+using ParkingLotApi.Models;
+
+namespace ParkingLotApi.Repositories
+{
+    public interface IParkingLotsRepository
+    {
+        Task<ParkingLotEntity> CreateParkingLotAsync(ParkingLotEntity parkingLo);
+        Task<bool> DeleteParkingLotAsync(string id);
+        Task<List<ParkingLotEntity>> GetAllAsync();
+        Task<ParkingLotEntity> GetByIdAsync(string id);
+        Task<ParkingLotEntity> UpdateCapacity(string id, ParkingLotEntity updatedParkingLot);
+    }
+}
diff --git a/ParkingLotApi/Repositories/ParkingLotsRepository.cs b/ParkingLotApi/Repositories/ParkingLotsRepository.cs
new file mode 100644
index 0000000..7fe8e4d
--- /dev/null
+++ b/ParkingLotApi/Repositories/ParkingLotsRepository.cs
@@ -0,0 +1,49 @@
+using Microsoft.Extensions.Options;
+using MongoDB.Driver;
+using ParkingLotApi.Models;
+
+namespace ParkingLotApi.Repositories
+{
+
+    public class ParkingLotsRepository : IParkingLotsRepository
+    {
+        private readonly IMongoCollection<ParkingLotEntity> _parkingLotsCollection;
+        public ParkingLotsRepository(IOptions<ParkingLotsDatabaseSettings> parkingLotsDatabaseSettings)
+        {
+            var mongoClient = new MongoClient(parkingLotsDatabaseSettings.Value.ConnectionString);
+            var mongoDatabase = mongoClient.GetDatabase(parkingLotsDatabaseSettings.Value.DatabaseName);
+            _parkingLotsCollection = mongoDatabase.GetCollection<ParkingLotEntity>(parkingLotsDatabaseSettings.Value.CollectionName);
+
+        }
+
+        public async Task<ParkingLotEntity> CreateParkingLotAsync(ParkingLotEntity parkingLot)
+        {
+            await _parkingLotsCollection.InsertOneAsync(parkingLot);
+            return await _parkingLotsCollection.Find(a => a.Name == parkingLot.Name).FirstAsync();
+        }
+
+        public async Task<bool> DeleteParkingLotAsync(string id)
+        {
+            var result = await _parkingLotsCollection.DeleteOneAsync(p => p.Id == id);
+            return result.DeletedCount > 0;
+        }
+
+        public async Task<List<ParkingLotEntity>> GetAllAsync()
+        {
+            return await _parkingLotsCollection.Find(_ => true).ToListAsync();
+        }
+
+        public async Task<ParkingLotEntity> GetByIdAsync(string id)
+        {
+            return await _parkingLotsCollection.Find(p => p.Id == id).FirstOrDefaultAsync();
+        } 
+
+        public async Task<ParkingLotEntity?> UpdateCapacity(string id, ParkingLotEntity updatedParkingLot)
+        {
+            await _parkingLotsCollection.ReplaceOneAsync(p => p.Id == id, updatedParkingLot);
+            return await GetByIdAsync(id);
+        }
+
+
+    }
+}
diff --git a/ParkingLotApi/Services/ParkingLotsService.cs b/ParkingLotApi/Services/ParkingLotsService.cs
new file mode 100644
index 0000000..ce52c72
--- /dev/null
+++ b/ParkingLotApi/Services/ParkingLotsService.cs
@@ -0,0 +1,63 @@
+using ParkingLotApi.Exceptions;
+using ParkingLotApi.Models;
+using ParkingLotApi.Repositories;
+using System;
+
+namespace ParkingLotApi.Services
+{
+    public class ParkingLotsService
+    {
+        private readonly IParkingLotsRepository _parkingLotsRepository;
+        public ParkingLotsService(IParkingLotsRepository parkingLotsRepository) {
+            _parkingLotsRepository = parkingLotsRepository;
+        }
+        public async Task<ParkingLotEntity> AddAsync(ParkingLotDto parkingLotDto)
+        {
+            if (parkingLotDto.Capacity < 10)
+            {
+                throw new InvalidCapacityException("The capacity should be no less than 10");
+            }
+            return await _parkingLotsRepository.CreateParkingLotAsync(parkingLotDto.ToEntity());
+        }
+
+        public async Task<bool> RemoveAsync(string id)
+        {
+            return await _parkingLotsRepository.DeleteParkingLotAsync(id);
+        }
+
+        public async Task<List<ParkingLotEntity>> GetOnePageParkingLots(int pageIndex)
+        {
+            var allParkingLots =  await _parkingLotsRepository.GetAllAsync();
+            int pageSize = 15;
+            int startIdx = (int)((pageIndex - 1) * pageSize);
+            return allParkingLots.Skip(startIdx).Take((int)pageSize).ToList();
+        }
+
+        public async Task<ParkingLotEntity> GetByIdAsync(string id)
+        {
+            return await _parkingLotsRepository.GetByIdAsync(id);
+        }
+
+        public IParkingLotsRepository Get_parkingLotsRepository()
+        {
+            return _parkingLotsRepository;
+        }
+
+        public async Task<ParkingLotEntity?> UpdateCapacity(string id, int capacity)
+        {
+            var parkingLot = await _parkingLotsRepository.GetByIdAsync(id);
+            if (parkingLot != null)
+            {
+                var updatedParkingLot = new ParkingLotEntity()
+                {
+                    Capacity = capacity,
+                    Id = parkingLot.Id,
+                    Name = parkingLot.Name,
+                    Location = parkingLot.Location
+                };
+                return await _parkingLotsRepository.UpdateCapacity(id, updatedParkingLot);
+            }
+            return null;
+        }
+    }
+}
diff --git a/ParkingLotApi/appsettings.json b/ParkingLotApi/appsettings.json
index 10f68b8..f359a48 100644
--- a/ParkingLotApi/appsettings.json
+++ b/ParkingLotApi/appsettings.json
@@ -5,5 +5,10 @@
       "Microsoft.AspNetCore": "Warning"
     }
   },
-  "AllowedHosts": "*"
+  "AllowedHosts": "*",
+  "ParkingLotsDataBase": {
+    "ConnectionString": "mongodb://localhost:27017/",
+    "DatabaseName": "ParkingLots",
+    "CollectionName": "ParkingLots"
+  }
 }
diff --git a/ParkingLotApiTest/ControllerTests/ParkingLotsControllerTest.cs b/ParkingLotApiTest/ControllerTests/ParkingLotsControllerTest.cs
new file mode 100644
index 0000000..8303b52
--- /dev/null
+++ b/ParkingLotApiTest/ControllerTests/ParkingLotsControllerTest.cs
@@ -0,0 +1,37 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.VisualStudio.TestPlatform.TestHost;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+using ParkingLotApiTest;
+using System.Net.Http.Json;
+using ParkingLotApi.Models;
+
+namespace ParkingLotApiTest.ControllerTests
+{
+    public class ParkingLotsControllerTest : TestBase
+    {
+
+        public ParkingLotsControllerTest (WebApplicationFactory<Program> factory) : base(factory) { }
+
+        [Fact]
+        public async Task Should_return_400_When_weatherForcast()
+        {
+            //given & when
+            HttpClient _httpClient = GetClient();
+            ParkingLotDto parkingLotWithLessThan10 = new ParkingLotDto()
+            {
+                Name = "ParkingLot1",
+                Capacity = 1,
+                Location = "Chengfu LU"
+            };
+            HttpResponseMessage response = await _httpClient.PostAsJsonAsync("/ParkingLots", parkingLotWithLessThan10);
+
+            Assert.Equal(HttpStatusCode.BadRequest, response.StatusCode);
+        }
+    }
+}
diff --git a/ParkingLotApiTest/ControllerTests/WeatherForcastControllerTest.cs b/ParkingLotApiTest/ControllerTests/WeatherForcastControllerTest.cs
new file mode 100644
index 0000000..daf2c43
--- /dev/null
+++ b/ParkingLotApiTest/ControllerTests/WeatherForcastControllerTest.cs
@@ -0,0 +1,30 @@
+using Microsoft.AspNetCore.Builder;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.VisualStudio.TestPlatform.TestHost;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+using ParkingLotApiTest;
+
+namespace ParkingLotApiTest.ControllerTests
+{
+    public class WeatherForcastControllerTest : TestBase
+    {
+
+        public WeatherForcastControllerTest(WebApplicationFactory<Program> factory) : base(factory)
+        {
+        }
+        [Fact]
+        public async Task Should_return_correctly_When_weatherForcast()
+        {
+            //given & when
+            HttpClient _httpClient = GetClient();
+            HttpResponseMessage response = await _httpClient.GetAsync("/WeatherForecast");
+
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+        }
+    }
+}
diff --git a/ParkingLotApiTest/TestBase.cs b/ParkingLotApiTest/TestBase.cs
new file mode 100644
index 0000000..0deb10a
--- /dev/null
+++ b/ParkingLotApiTest/TestBase.cs
@@ -0,0 +1,29 @@
+using Microsoft.AspNetCore.Hosting;
+using Microsoft.AspNetCore.Identity;
+using Microsoft.AspNetCore.Mvc.Testing;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace ParkingLotApiTest
+{
+    public class TestBase : IClassFixture<WebApplicationFactory<Program>>
+    {
+        public TestBase(WebApplicationFactory<Program> factory) 
+        { 
+            this.Factory = factory;
+        }
+
+        protected WebApplicationFactory<Program> Factory { get; }
+
+        protected HttpClient GetClient()
+        {
+            return Factory.CreateClient();
+        }
+
+    }
+
+
+}
diff --git a/api.http b/api.http
new file mode 100644
index 0000000..e7197fa
--- /dev/null
+++ b/api.http
@@ -0,0 +1,66 @@
+# For more info on HTTP files go to https://aka.ms/vs/httpfile
+
+@hostname=localhost
+@port=??
+
+# ParkingLot APIS
+## POST /api/ParkingLots
+## GET /api/ParkingLots
+## GET /api/ParkingLots/{name}
+## GET /api/ParkingLots?page-size={x}&index={y}
+## PUT /api/ParkingLots/{name}
+## DELETE /api/ParkingLots/{name}
+
+## 1. Create ParkingLot
+POST http://{{hostname}}:{{port}}/api/ParkingLots
+Content-Type: application/json; charset=utf-8
+
+{
+    "Name": "parkinglot one",
+    "Capacity" : 10,
+    "Location" : "Chengfu Road"
+}
+
+## Response 
+{
+    "Id": "fdjsljldbvjsal",
+    "Name": "parkinglot one",
+    "Capacity" : 10,
+    "Location" : "Chengfu Road"
+}
+### 1.Created, Return the parkinglot created with Status Created ( 201 )
+### 2.Already Existed, Return Status Bad Request ( 400 )
+### 3.Required Message Invalidation, Return Status Bad Request (400)
+
+## 2. Delete An Empoyee to Specific Company
+POST http://{{hostname}}:{{port}}/api/ParkingLosts/{id}
+Content-Type: application/json; charset=utf-8
+## Response 
+### 1.NoContent with the employee deleted successfully (204)
+### 2.NotFound as the company_id or employee_id is wrong （404）
+
+## 3.Get One Page ParkingLots
+GET http://{{hostname}}:{{port}}/api/ParkingLots?pageIndex={index}
+Content-Type: application/json; charset=utf-8
+
+## Response  
+### 1.Found, Return all ParkingLots Entity Found with Status OK ( 200 )
+
+## 4. Get ParkingLot By ParkingLot_ID
+GET http://{{hostname}}:{{port}}/api/ParkingLots/{id}
+## Response  
+###  1.Found, Return the ParkingLot Entity Found with Status OK ( 200 )
+###  2.Not Found, Return Status Not Found ( 404 )
+
+## 5. PUT Update Capacity of One ParkingLot Given ID
+PUT http://{{hostname}}:{{port}}/api/ParkingLots/{id}
+Content-Type: application/json; charset=utf-8
+
+## Body
+{
+    "Capacity" : 20
+}
+
+## Response  
+## 1.Updated,  Return the ParkingLot updated with Status OK ( 200 )
+## 2.Not Found, Return Status Not Found ( 404 )