Merge pull request #48 from crupest/user-details

Add user details.

12 files changed, 682 insertions, 19 deletions

diff --git a/Timeline/Controllers/UserDetailController.cs b/Timeline/Controllers/UserDetailController.cs
new file mode 100644
index 00000000..5e1183c1
--- /dev/null
+++ b/Timeline/Controllers/UserDetailController.cs
@@ -0,0 +1,96 @@
+using Microsoft.AspNetCore.Authorization;

+using Microsoft.AspNetCore.Http;

+using Microsoft.AspNetCore.Mvc;

+using Microsoft.Extensions.Logging;

+using System.Threading.Tasks;

+using Timeline.Authenticate;

+using Timeline.Models;

+using Timeline.Models.Http;

+using Timeline.Services;

+

+namespace Timeline.Controllers

+{

+    [Route("users/{username}")]

+    [ProducesErrorResponseType(typeof(CommonResponse))]

+    [ApiController]

+    public class UserDetailController : Controller

+    {

+        public static class ErrorCodes

+        {

+            public const int Get_UserNotExist = -1001;

+

+            public const int Patch_Forbid = -2001;

+            public const int Patch_UserNotExist = -2002;

+

+            public const int GetNickname_UserNotExist = -3001;

+        }

+

+        private readonly ILogger<UserDetailController> _logger;

+        private readonly IUserDetailService _service;

+

+        public UserDetailController(ILogger<UserDetailController> logger, IUserDetailService service)

+        {

+            _logger = logger;

+            _service = service;

+        }

+

+        [HttpGet("nickname")]

+        [UserAuthorize]

+        [ProducesResponseType(StatusCodes.Status200OK, Type = typeof(UserDetail))]

+        [ProducesResponseType(StatusCodes.Status404NotFound)]

+        public async Task<IActionResult> GetNickname([FromRoute] string username)

+        {

+            try

+            {

+                var nickname = await _service.GetUserNickname(username);

+                return Ok(new UserDetail

+                {

+                    Nickname = nickname

+                });

+            }

+            catch (UserNotExistException)

+            {

+                return NotFound(new CommonResponse(ErrorCodes.GetNickname_UserNotExist, "The user does not exist."));

+            }

+        }

+

+        [HttpGet("details")]

+        [UserAuthorize]

+        [ProducesResponseType(StatusCodes.Status200OK, Type = typeof(UserDetail))]

+        [ProducesResponseType(StatusCodes.Status404NotFound)]

+        public async Task<IActionResult> Get([FromRoute] string username)

+        {

+            try

+            {

+                var detail = await _service.GetUserDetail(username);

+                return Ok(detail);

+            }

+            catch (UserNotExistException)

+            {

+                return NotFound(new CommonResponse(ErrorCodes.Get_UserNotExist, "The user does not exist."));

+            }

+        }

+

+        [HttpPatch("details")]

+        [Authorize]

+        [ProducesResponseType(StatusCodes.Status200OK, Type = typeof(void))]

+        [ProducesResponseType(StatusCodes.Status400BadRequest)]

+        [ProducesResponseType(StatusCodes.Status403Forbidden)]

+        [ProducesResponseType(StatusCodes.Status404NotFound)]

+        public async Task<IActionResult> Patch([FromRoute] string username, [FromBody] UserDetail detail)

+        {

+            if (!User.IsAdmin() && User.Identity.Name != username)

+                return StatusCode(StatusCodes.Status403Forbidden, new CommonResponse(ErrorCodes.Patch_Forbid, "You can't change other's details unless you are admin."));

+

+            try

+            {

+                await _service.UpdateUserDetail(username, detail);

+                return Ok();

+            }

+            catch (UserNotExistException)

+            {

+                return NotFound(new CommonResponse(ErrorCodes.Patch_UserNotExist, "The user does not exist."));

+            }

+        }

+    }

+}

diff --git a/Timeline/Entities/DatabaseContext.cs b/Timeline/Entities/DatabaseContext.cs
index 6e1fc638..d9815660 100644
--- a/Timeline/Entities/DatabaseContext.cs
+++ b/Timeline/Entities/DatabaseContext.cs
@@ -28,8 +28,9 @@ namespace Timeline.Entities
         [Column("version"), Required]

         public long Version { get; set; }

 

-        [Required]

         public UserAvatar Avatar { get; set; }

+

+        public UserDetailEntity Detail { get; set; }

     }

 

     public class DatabaseContext : DbContext

@@ -48,5 +49,6 @@ namespace Timeline.Entities
 

         public DbSet<User> Users { get; set; }

         public DbSet<UserAvatar> UserAvatars { get; set; }

+        public DbSet<UserDetailEntity> UserDetails { get; set; }

     }

 }

diff --git a/Timeline/Entities/UserDetail.cs b/Timeline/Entities/UserDetail.cs
new file mode 100644
index 00000000..6e582234
--- /dev/null
+++ b/Timeline/Entities/UserDetail.cs
@@ -0,0 +1,29 @@
+using System.ComponentModel.DataAnnotations;

+using System.ComponentModel.DataAnnotations.Schema;

+

+namespace Timeline.Entities

+{

+    [Table("user_details")]

+    public class UserDetailEntity

+    {

+        [Column("id"), Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]

+        public long Id { get; set; }

+

+        [Column("nickname"), MaxLength(15)]

+        public string Nickname { get; set; }

+

+        [Column("qq"), MaxLength(15)]

+        public string QQ { get; set; }

+

+        [Column("email"), MaxLength(50)]

+        public string EMail { get; set; }

+

+        [Column("phone_number"), MaxLength(15)]

+        public string PhoneNumber { get; set; }

+

+        [Column("description")]

+        public string Description { get; set; }

+

+        public long UserId { get; set; }

+    }

+}

diff --git a/Timeline/Migrations/20190822072156_AddUserDetail.Designer.cs b/Timeline/Migrations/20190822072156_AddUserDetail.Designer.cs
new file mode 100644
index 00000000..2bbcf673
--- /dev/null
+++ b/Timeline/Migrations/20190822072156_AddUserDetail.Designer.cs
@@ -0,0 +1,136 @@
+// <auto-generated />

+using System;

+using Microsoft.EntityFrameworkCore;

+using Microsoft.EntityFrameworkCore.Infrastructure;

+using Microsoft.EntityFrameworkCore.Migrations;

+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;

+using Timeline.Entities;

+

+namespace Timeline.Migrations

+{

+    [DbContext(typeof(DatabaseContext))]

+    [Migration("20190822072156_AddUserDetail")]

+    partial class AddUserDetail

+    {

+        protected override void BuildTargetModel(ModelBuilder modelBuilder)

+        {

+#pragma warning disable 612, 618

+            modelBuilder

+                .HasAnnotation("ProductVersion", "2.2.6-servicing-10079")

+                .HasAnnotation("Relational:MaxIdentifierLength", 64);

+

+            modelBuilder.Entity("Timeline.Entities.User", b =>

+                {

+                    b.Property<long>("Id")

+                        .ValueGeneratedOnAdd()

+                        .HasColumnName("id");

+

+                    b.Property<string>("EncryptedPassword")

+                        .IsRequired()

+                        .HasColumnName("password");

+

+                    b.Property<string>("Name")

+                        .IsRequired()

+                        .HasColumnName("name")

+                        .HasMaxLength(26);

+

+                    b.Property<string>("RoleString")

+                        .IsRequired()

+                        .HasColumnName("roles");

+

+                    b.Property<long>("Version")

+                        .ValueGeneratedOnAdd()

+                        .HasColumnName("version")

+                        .HasDefaultValue(0L);

+

+                    b.HasKey("Id");

+

+                    b.HasIndex("Name")

+                        .IsUnique();

+

+                    b.ToTable("users");

+                });

+

+            modelBuilder.Entity("Timeline.Entities.UserAvatar", b =>

+                {

+                    b.Property<long>("Id")

+                        .ValueGeneratedOnAdd()

+                        .HasColumnName("id");

+

+                    b.Property<byte[]>("Data")

+                        .HasColumnName("data");

+

+                    b.Property<string>("ETag")

+                        .HasColumnName("etag")

+                        .HasMaxLength(30);

+

+                    b.Property<DateTime>("LastModified")

+                        .HasColumnName("last_modified");

+

+                    b.Property<string>("Type")

+                        .HasColumnName("type");

+

+                    b.Property<long>("UserId");

+

+                    b.HasKey("Id");

+

+                    b.HasIndex("UserId")

+                        .IsUnique();

+

+                    b.ToTable("user_avatars");

+                });

+

+            modelBuilder.Entity("Timeline.Entities.UserDetailEntity", b =>

+                {

+                    b.Property<long>("Id")

+                        .ValueGeneratedOnAdd()

+                        .HasColumnName("id");

+

+                    b.Property<string>("Description")

+                        .HasColumnName("description");

+

+                    b.Property<string>("EMail")

+                        .HasColumnName("email")

+                        .HasMaxLength(50);

+

+                    b.Property<string>("Nickname")

+                        .HasColumnName("nickname")

+                        .HasMaxLength(15);

+

+                    b.Property<string>("PhoneNumber")

+                        .HasColumnName("phone_number")

+                        .HasMaxLength(15);

+

+                    b.Property<string>("QQ")

+                        .HasColumnName("qq")

+                        .HasMaxLength(15);

+

+                    b.Property<long>("UserId");

+

+                    b.HasKey("Id");

+

+                    b.HasIndex("UserId")

+                        .IsUnique();

+

+                    b.ToTable("user_details");

+                });

+

+            modelBuilder.Entity("Timeline.Entities.UserAvatar", b =>

+                {

+                    b.HasOne("Timeline.Entities.User")

+                        .WithOne("Avatar")

+                        .HasForeignKey("Timeline.Entities.UserAvatar", "UserId")

+                        .OnDelete(DeleteBehavior.Cascade);

+                });

+

+            modelBuilder.Entity("Timeline.Entities.UserDetailEntity", b =>

+                {

+                    b.HasOne("Timeline.Entities.User")

+                        .WithOne("Detail")

+                        .HasForeignKey("Timeline.Entities.UserDetailEntity", "UserId")

+                        .OnDelete(DeleteBehavior.Cascade);

+                });

+#pragma warning restore 612, 618

+        }

+    }

+}

diff --git a/Timeline/Migrations/20190822072156_AddUserDetail.cs b/Timeline/Migrations/20190822072156_AddUserDetail.cs
new file mode 100644
index 00000000..4aa6446b
--- /dev/null
+++ b/Timeline/Migrations/20190822072156_AddUserDetail.cs
@@ -0,0 +1,47 @@
+using Microsoft.EntityFrameworkCore.Metadata;

+using Microsoft.EntityFrameworkCore.Migrations;

+

+namespace Timeline.Migrations

+{

+    public partial class AddUserDetail : Migration

+    {

+        protected override void Up(MigrationBuilder migrationBuilder)

+        {

+            migrationBuilder.CreateTable(

+                name: "user_details",

+                columns: table => new

+                {

+                    id = table.Column<long>(nullable: false)

+                        .Annotation("MySql:ValueGenerationStrategy", MySqlValueGenerationStrategy.IdentityColumn),

+                    nickname = table.Column<string>(maxLength: 15, nullable: true),

+                    qq = table.Column<string>(maxLength: 15, nullable: true),

+                    email = table.Column<string>(maxLength: 50, nullable: true),

+                    phone_number = table.Column<string>(maxLength: 15, nullable: true),

+                    description = table.Column<string>(nullable: true),

+                    UserId = table.Column<long>(nullable: false)

+                },

+                constraints: table =>

+                {

+                    table.PrimaryKey("PK_user_details", x => x.id);

+                    table.ForeignKey(

+                        name: "FK_user_details_users_UserId",

+                        column: x => x.UserId,

+                        principalTable: "users",

+                        principalColumn: "id",

+                        onDelete: ReferentialAction.Cascade);

+                });

+

+            migrationBuilder.CreateIndex(

+                name: "IX_user_details_UserId",

+                table: "user_details",

+                column: "UserId",

+                unique: true);

+        }

+

+        protected override void Down(MigrationBuilder migrationBuilder)

+        {

+            migrationBuilder.DropTable(

+                name: "user_details");

+        }

+    }

+}

diff --git a/Timeline/Migrations/DatabaseContextModelSnapshot.cs b/Timeline/Migrations/DatabaseContextModelSnapshot.cs
index 4941321c..1328b855 100644
--- a/Timeline/Migrations/DatabaseContextModelSnapshot.cs
+++ b/Timeline/Migrations/DatabaseContextModelSnapshot.cs
@@ -78,6 +78,41 @@ namespace Timeline.Migrations
                     b.ToTable("user_avatars");

                 });

 

+            modelBuilder.Entity("Timeline.Entities.UserDetailEntity", b =>

+                {

+                    b.Property<long>("Id")

+                        .ValueGeneratedOnAdd()

+                        .HasColumnName("id");

+

+                    b.Property<string>("Description")

+                        .HasColumnName("description");

+

+                    b.Property<string>("EMail")

+                        .HasColumnName("email")

+                        .HasMaxLength(50);

+

+                    b.Property<string>("Nickname")

+                        .HasColumnName("nickname")

+                        .HasMaxLength(15);

+

+                    b.Property<string>("PhoneNumber")

+                        .HasColumnName("phone_number")

+                        .HasMaxLength(15);

+

+                    b.Property<string>("QQ")

+                        .HasColumnName("qq")

+                        .HasMaxLength(15);

+

+                    b.Property<long>("UserId");

+

+                    b.HasKey("Id");

+

+                    b.HasIndex("UserId")

+                        .IsUnique();

+

+                    b.ToTable("user_details");

+                });

+

             modelBuilder.Entity("Timeline.Entities.UserAvatar", b =>

                 {

                     b.HasOne("Timeline.Entities.User")

@@ -85,6 +120,14 @@ namespace Timeline.Migrations
                         .HasForeignKey("Timeline.Entities.UserAvatar", "UserId")

                         .OnDelete(DeleteBehavior.Cascade);

                 });

+

+            modelBuilder.Entity("Timeline.Entities.UserDetailEntity", b =>

+                {

+                    b.HasOne("Timeline.Entities.User")

+                        .WithOne("Detail")

+                        .HasForeignKey("Timeline.Entities.UserDetailEntity", "UserId")

+                        .OnDelete(DeleteBehavior.Cascade);

+                });

 #pragma warning restore 612, 618

         }

     }

diff --git a/Timeline/Models/UserDetail.cs b/Timeline/Models/UserDetail.cs
new file mode 100644
index 00000000..86866d8b
--- /dev/null
+++ b/Timeline/Models/UserDetail.cs
@@ -0,0 +1,43 @@
+using System.ComponentModel.DataAnnotations;

+using Timeline.Entities;

+using Timeline.Models.Validation;

+

+namespace Timeline.Models

+{

+    public class UserDetail

+    {

+        [MaxLength(10)]

+        public string Nickname { get; set; }

+

+        [ValidateWith(typeof(UserDetailValidators.QQValidator))]

+        public string QQ { get; set; }

+

+        [ValidateWith(typeof(UserDetailValidators.EMailValidator))]

+        public string EMail { get; set; }

+

+        [ValidateWith(typeof(UserDetailValidators.PhoneNumberValidator))]

+        public string PhoneNumber { get; set; }

+

+        public string Description { get; set; }

+

+        private static string CoerceEmptyToNull(string value)

+        {

+            if (string.IsNullOrEmpty(value))

+                return null;

+            else

+                return value;

+        }

+

+        public static UserDetail From(UserDetailEntity entity)

+        {

+            return new UserDetail

+            {

+                Nickname = CoerceEmptyToNull(entity.Nickname),

+                QQ = CoerceEmptyToNull(entity.QQ),

+                EMail = CoerceEmptyToNull(entity.EMail),

+                PhoneNumber = CoerceEmptyToNull(entity.PhoneNumber),

+                Description = CoerceEmptyToNull(entity.Description)

+            };

+        }

+    }

+}

diff --git a/Timeline/Models/Validation/UserDetailValidator.cs b/Timeline/Models/Validation/UserDetailValidator.cs
new file mode 100644
index 00000000..19c82edb
--- /dev/null
+++ b/Timeline/Models/Validation/UserDetailValidator.cs
@@ -0,0 +1,116 @@
+using System;

+using System.Net.Mail;

+

+namespace Timeline.Models.Validation

+{

+    public abstract class OptionalStringValidator : IValidator

+    {

+        public bool Validate(object value, out string message)

+        {

+            if (value == null)

+            {

+                message = ValidationConstants.SuccessMessage;

+                return true;

+            }

+

+            if (value is string s)

+            {

+                if (s.Length == 0)

+                {

+                    message = ValidationConstants.SuccessMessage;

+                    return true;

+                }

+                return DoValidate(s, out message);

+            }

+            else

+            {

+                message = "Value is not of type string.";

+                return false;

+            }

+        }

+

+        protected abstract bool DoValidate(string value, out string message);

+    }

+

+    public static class UserDetailValidators

+    {

+

+        public class QQValidator : OptionalStringValidator

+        {

+            protected override bool DoValidate(string value, out string message)

+            {

+                if (value.Length < 5)

+                {

+                    message = "QQ is too short.";

+                    return false;

+                }

+

+                if (value.Length > 11)

+                {

+                    message = "QQ is too long.";

+                    return false;

+                }

+

+                foreach (var c in value)

+                {

+                    if (!char.IsDigit(c))

+                    {

+                        message = "QQ must only contain digit.";

+                        return false;

+                    }

+                }

+

+                message = ValidationConstants.SuccessMessage;

+                return true;

+            }

+        }

+

+        public class EMailValidator : OptionalStringValidator

+        {

+            protected override bool DoValidate(string value, out string message)

+            {

+                if (value.Length > 50)

+                {

+                    message = "E-Mail is too long.";

+                    return false;

+                }

+

+                try

+                {

+                    var _ = new MailAddress(value);

+                }

+                catch (FormatException)

+                {

+                    message = "The format of E-Mail is bad.";

+                    return false;

+                }

+                message = ValidationConstants.SuccessMessage;

+                return true;

+            }

+        }

+

+        public class PhoneNumberValidator : OptionalStringValidator

+        {

+            protected override bool DoValidate(string value, out string message)

+            {

+                if (value.Length > 14)

+                {

+                    message = "Phone number is too long.";

+                    return false;

+                }

+

+                foreach (var c in value)

+                {

+                    if (!char.IsDigit(c))

+                    {

+                        message = "Phone number can only contain digit.";

+                        return false;

+                    }

+                }

+

+                message = ValidationConstants.SuccessMessage;

+                return true;

+            }

+        }

+    }

+}

diff --git a/Timeline/Services/DatabaseExtensions.cs b/Timeline/Services/DatabaseExtensions.cs
new file mode 100644
index 00000000..a37cf05b
--- /dev/null
+++ b/Timeline/Services/DatabaseExtensions.cs
@@ -0,0 +1,30 @@
+using Microsoft.EntityFrameworkCore;

+using System;

+using System.Collections.Generic;

+using System.Linq;

+using System.Threading.Tasks;

+using Timeline.Entities;

+

+namespace Timeline.Services

+{

+    public static class DatabaseExtensions

+    {

+        /// <summary>

+        /// Check the existence and get the id of the user.

+        /// </summary>

+        /// <param name="username">The username of the user.</param>

+        /// <returns>The user id.</returns>

+        /// <exception cref="ArgumentException">Thrown if <paramref name="username"/> is null or empty.</exception>

+        /// <exception cref="UserNotExistException">Thrown if user does not exist.</exception>

+        public static async Task<long> CheckAndGetUser(DbSet<User> userDbSet, string username)

+        {

+            if (string.IsNullOrEmpty(username))

+                throw new ArgumentException("Username is null or empty.", nameof(username));

+

+            var userId = await userDbSet.Where(u => u.Name == username).Select(u => u.Id).SingleOrDefaultAsync();

+            if (userId == 0)

+                throw new UserNotExistException(username);

+            return userId;

+        }

+    }

+}

diff --git a/Timeline/Services/UserAvatarService.cs b/Timeline/Services/UserAvatarService.cs
index 7b1f405c..5c380dd8 100644
--- a/Timeline/Services/UserAvatarService.cs
+++ b/Timeline/Services/UserAvatarService.cs
@@ -219,12 +219,7 @@ namespace Timeline.Services
 

         public async Task<string> GetAvatarETag(string username)

         {

-            if (string.IsNullOrEmpty(username))

-                throw new ArgumentException("Username is null or empty.", nameof(username));

-

-            var userId = await _database.Users.Where(u => u.Name == username).Select(u => u.Id).SingleOrDefaultAsync();

-            if (userId == 0)

-                throw new UserNotExistException(username);

+            var userId = await DatabaseExtensions.CheckAndGetUser(_database.Users, username);

 

             var eTag = (await _database.UserAvatars.Where(a => a.UserId == userId).Select(a => new { a.ETag }).SingleAsync()).ETag;

             if (eTag == null)

@@ -235,12 +230,7 @@ namespace Timeline.Services
 

         public async Task<AvatarInfo> GetAvatar(string username)

         {

-            if (string.IsNullOrEmpty(username))

-                throw new ArgumentException("Username is null or empty.", nameof(username));

-

-            var userId = await _database.Users.Where(u => u.Name == username).Select(u => u.Id).SingleOrDefaultAsync();

-            if (userId == 0)

-                throw new UserNotExistException(username);

+            var userId = await DatabaseExtensions.CheckAndGetUser(_database.Users, username);

 

             var avatar = await _database.UserAvatars.Where(a => a.UserId == userId).Select(a => new { a.Type, a.Data, a.LastModified }).SingleAsync();

 

@@ -272,9 +262,6 @@ namespace Timeline.Services
 

         public async Task SetAvatar(string username, Avatar avatar)

         {

-            if (string.IsNullOrEmpty(username))

-                throw new ArgumentException("Username is null or empty.", nameof(username));

-

             if (avatar != null)

             {

                 if (string.IsNullOrEmpty(avatar.Type))

@@ -283,9 +270,7 @@ namespace Timeline.Services
                     throw new ArgumentException("Data of avatar is null.", nameof(avatar));

             }

 

-            var userId = await _database.Users.Where(u => u.Name == username).Select(u => u.Id).SingleOrDefaultAsync();

-            if (userId == 0)

-                throw new UserNotExistException(username);

+            var userId = await DatabaseExtensions.CheckAndGetUser(_database.Users, username);

 

             var avatarEntity = await _database.UserAvatars.Where(a => a.UserId == userId).SingleAsync();

 

diff --git a/Timeline/Services/UserDetailService.cs b/Timeline/Services/UserDetailService.cs
new file mode 100644
index 00000000..a8ed662b
--- /dev/null
+++ b/Timeline/Services/UserDetailService.cs
@@ -0,0 +1,135 @@
+using Microsoft.EntityFrameworkCore;

+using Microsoft.Extensions.DependencyInjection;

+using Microsoft.Extensions.Logging;

+using System;

+using System.Linq;

+using System.Threading.Tasks;

+using Timeline.Entities;

+using Timeline.Models;

+

+namespace Timeline.Services

+{

+    public interface IUserDetailService

+    {

+        /// <summary>

+        /// Get the nickname of user.

+        /// </summary>

+        /// <param name="username">The username to get nickname of.</param>

+        /// <returns>The user's nickname. Null if not set.</returns>

+        /// <exception cref="ArgumentException">Thrown if <paramref name="username"/> is null or empty.</exception>

+        /// <exception cref="UserNotExistException">Thrown if user doesn't exist.</exception>

+        Task<string> GetUserNickname(string username);

+

+        /// <summary>

+        /// Get the detail of user.

+        /// </summary>

+        /// <param name="username">The username to get user detail of.</param>

+        /// <returns>The user detail.</returns>

+        /// <exception cref="ArgumentException">Thrown if <paramref name="username"/> is null or empty.</exception>

+        /// <exception cref="UserNotExistException">Thrown if user doesn't exist.</exception>

+        Task<UserDetail> GetUserDetail(string username);

+

+        /// <summary>

+        /// Update the detail of user. This function does not do data check.

+        /// </summary>

+        /// <param name="username">The username to get user detail of.</param>

+        /// <param name="detail">The detail to update. Can't be null. Any null member means not set.</param>

+        /// <exception cref="ArgumentException">Thrown if <paramref name="username"/> is null or empty or <paramref name="detail"/> is null.</exception>

+        /// <exception cref="UserNotExistException">Thrown if user doesn't exist.</exception>

+        Task UpdateUserDetail(string username, UserDetail detail);

+    }

+

+    public class UserDetailService : IUserDetailService

+    {

+        private readonly ILogger<UserDetailService> _logger;

+

+        private readonly DatabaseContext _databaseContext;

+

+        public UserDetailService(ILogger<UserDetailService> logger, DatabaseContext databaseContext)

+        {

+            _logger = logger;

+            _databaseContext = databaseContext;

+        }

+

+        private async Task<UserDetailEntity> CreateEntity(long userId)

+        {

+            var entity = new UserDetailEntity()

+            {

+                UserId = userId

+            };

+            _databaseContext.UserDetails.Add(entity);

+            await _databaseContext.SaveChangesAsync();

+            _logger.LogInformation("An entity is created in user_details.");

+            return entity;

+        }

+

+        // Check the existence of user detail entry

+        private async Task<UserDetailEntity> CheckAndInit(long userId)

+        {

+            var detail = await _databaseContext.UserDetails.Where(e => e.UserId == userId).SingleOrDefaultAsync();

+            if (detail == null)

+            {

+                detail = await CreateEntity(userId);

+            }

+            return detail;

+        }

+

+        public async Task<string> GetUserNickname(string username)

+        {

+            var userId = await DatabaseExtensions.CheckAndGetUser(_databaseContext.Users, username);

+            var detail = await _databaseContext.UserDetails.Where(e => e.UserId == userId).Select(e => new { e.Nickname }).SingleOrDefaultAsync();

+            if (detail == null)

+            {

+                var entity = await CreateEntity(userId);

+                return null;

+            }

+            else

+            {

+                var nickname = detail.Nickname;

+                return string.IsNullOrEmpty(nickname) ? null : nickname;

+            }

+        }

+

+        public async Task<UserDetail> GetUserDetail(string username)

+        {

+            var userId = await DatabaseExtensions.CheckAndGetUser(_databaseContext.Users, username);

+            var detailEntity = await CheckAndInit(userId);

+            return UserDetail.From(detailEntity);

+        }

+

+        public async Task UpdateUserDetail(string username, UserDetail detail)

+        {

+            if (detail == null)

+                throw new ArgumentNullException(nameof(detail));

+

+            var userId = await DatabaseExtensions.CheckAndGetUser(_databaseContext.Users, username);

+            var detailEntity = await CheckAndInit(userId);

+

+            if (detail.Nickname != null)

+                detailEntity.Nickname = detail.Nickname;

+

+            if (detail.QQ != null)

+                detailEntity.QQ = detail.QQ;

+

+            if (detail.EMail != null)

+                detailEntity.EMail = detail.EMail;

+

+            if (detail.PhoneNumber != null)

+                detailEntity.PhoneNumber = detail.PhoneNumber;

+

+            if (detail.Description != null)

+                detailEntity.Description = detail.Description;

+

+            await _databaseContext.SaveChangesAsync();

+            _logger.LogInformation("An entity is updated in user_details.");

+        }

+    }

+

+    public static class UserDetailServiceCollectionExtensions

+    {

+        public static void AddUserDetailService(this IServiceCollection services)

+        {

+            services.AddScoped<IUserDetailService, UserDetailService>();

+        }

+    }

+}

diff --git a/Timeline/Startup.cs b/Timeline/Startup.cs
index 66f648c3..b5a5106b 100644
--- a/Timeline/Startup.cs
+++ b/Timeline/Startup.cs
@@ -46,6 +46,7 @@ namespace Timeline
             services.AddTransient<IClock, Clock>();

 

             services.AddUserAvatarService();

+            services.AddUserDetailService();

 

             var databaseConfig = Configuration.GetSection(nameof(DatabaseConfig)).Get<DatabaseConfig>();