improvement: TagCode 도입 — 태그 식별자를 4자리 랜덤 코드로 변경 (#269)

Reviewed-on: https://git.ipstein.myds.me/SPMS/SPMS_API/pulls/270

.gitignore

@@ -62,4 +62,5 @@ Dockerfile
 Documents/
 CLAUDE.md
 TASKS.md
-.mcp.json
+TODO.md
+.mcp.json

SPMS.API/Controllers/TagController.cs

@@ -43,7 +43,8 @@ public class TagController : ControllerBase
     [SwaggerOperation(Summary = "태그 수정", Description = "태그 설명을 수정합니다. 태그명(Name)은 변경 불가.")]
     public async Task<IActionResult> UpdateAsync([FromBody] UpdateTagRequestDto request)
     {
-        var result = await _tagService.UpdateAsync(request);
+        var serviceId = GetServiceId();
+        var result = await _tagService.UpdateAsync(serviceId, request);
         return Ok(ApiResponse<TagResponseDto>.Success(result, "태그 수정 성공"));
     }
 
@@ -51,7 +52,8 @@ public class TagController : ControllerBase
     [SwaggerOperation(Summary = "태그 삭제", Description = "태그를 삭제합니다.")]
     public async Task<IActionResult> DeleteAsync([FromBody] DeleteTagRequestDto request)
     {
-        await _tagService.DeleteAsync(request);
+        var serviceId = GetServiceId();
+        await _tagService.DeleteAsync(serviceId, request);
         return Ok(ApiResponse.Success());
     }
 
@@ -62,6 +64,13 @@ public class TagController : ControllerBase
         return null;
     }
 
+    private long GetServiceId()
+    {
+        if (HttpContext.Items.TryGetValue("ServiceId", out var serviceIdObj) && serviceIdObj is long serviceId)
+            return serviceId;
+        throw new SpmsException(ErrorCodes.ServiceScopeRequired, "X-Service-Code 헤더가 필요합니다.", 400);
+    }
+
     private long GetAdminId()
     {
         var adminIdClaim = User.FindFirst("adminId")?.Value;

SPMS.API/Middlewares/ServiceCodeMiddleware.cs

@@ -35,7 +35,7 @@ public class ServiceCodeMiddleware
         if (path.StartsWithSegments("/v1/in/stats") ||
             path.StartsWithSegments("/v1/in/device/list") ||
             path.StartsWithSegments("/v1/in/message/list") ||
-            path.StartsWithSegments("/v1/in/tag"))
+            path == "/v1/in/tag/list")
         {
             if (context.Request.Headers.TryGetValue("X-Service-Code", out var optionalCode) &&
                 !string.IsNullOrWhiteSpace(optionalCode))

SPMS.Application/DTOs/Device/DeviceExportRequestDto.cs

@@ -11,7 +11,7 @@ public class DeviceExportRequestDto
     public bool? PushAgreed { get; set; }
 
     [JsonPropertyName("tags")]
-    public List<int>? Tags { get; set; }
+    public List<string>? Tags { get; set; }
 
     [JsonPropertyName("is_active")]
     public bool? IsActive { get; set; }

SPMS.Application/DTOs/Device/DeviceInfoResponseDto.cs

@@ -29,7 +29,7 @@ public class DeviceInfoResponseDto
     public bool MarketingAgreed { get; set; }
 
     [JsonPropertyName("tags")]
-    public List<int>? Tags { get; set; }
+    public List<string>? Tags { get; set; }
 
     [JsonPropertyName("is_active")]
     public bool IsActive { get; set; }

SPMS.Application/DTOs/Device/DeviceListRequestDto.cs

@@ -17,7 +17,7 @@ public class DeviceListRequestDto
     public bool? PushAgreed { get; set; }
 
     [JsonPropertyName("tags")]
-    public List<int>? Tags { get; set; }
+    public List<string>? Tags { get; set; }
 
     [JsonPropertyName("is_active")]
     public bool? IsActive { get; set; }

SPMS.Application/DTOs/Device/DeviceListResponseDto.cs

@@ -27,7 +27,7 @@ public class DeviceSummaryDto
     public bool PushAgreed { get; set; }
 
     [JsonPropertyName("tags")]
-    public List<int>? Tags { get; set; }
+    public List<string>? Tags { get; set; }
 
     [JsonPropertyName("last_active_at")]
     public DateTime? LastActiveAt { get; set; }

SPMS.Application/DTOs/Device/DeviceTagsRequestDto.cs

@@ -11,5 +11,5 @@ public class DeviceTagsRequestDto
 
     [Required]
     [JsonPropertyName("tags")]
-    public List<int> Tags { get; set; } = new();
+    public List<string> Tags { get; set; } = new();
 }

SPMS.Application/DTOs/Push/PushScheduleRequestDto.cs

@@ -12,7 +12,7 @@ public class PushScheduleRequestDto
 
     public long? DeviceId { get; set; }
 
-    public List<int>? Tags { get; set; }
+    public List<string>? Tags { get; set; }
 
     [Required]
     public string ScheduledAt { get; set; } = string.Empty;

SPMS.Application/DTOs/Push/PushSendTagRequestDto.cs

@@ -9,7 +9,7 @@ public class PushSendTagRequestDto
 
     [Required]
     [MinLength(1)]
-    public List<int> Tags { get; set; } = [];
+    public List<string> Tags { get; set; } = [];
 
     public string TagMatch { get; set; } = "or";
 }

SPMS.Application/DTOs/Tag/DeleteTagRequestDto.cs

@@ -6,6 +6,6 @@ namespace SPMS.Application.DTOs.Tag;
 public class DeleteTagRequestDto
 {
     [Required]
-    [JsonPropertyName("tag_id")]
-    public long TagId { get; set; }
+    [JsonPropertyName("tag_code")]
+    public string TagCode { get; set; } = string.Empty;
 }

SPMS.Application/DTOs/Tag/TagListResponseDto.cs

@@ -17,8 +17,8 @@ public class TagSummaryDto
     [JsonPropertyName("tag_index")]
     public int TagIndex { get; set; }
 
-    [JsonPropertyName("tag_id")]
-    public long TagId { get; set; }
+    [JsonPropertyName("tag_code")]
+    public string TagCode { get; set; } = string.Empty;
 
     [JsonPropertyName("tag_name")]
     public string TagName { get; set; } = string.Empty;

SPMS.Application/DTOs/Tag/TagResponseDto.cs

@@ -4,8 +4,8 @@ namespace SPMS.Application.DTOs.Tag;
 
 public class TagResponseDto
 {
-    [JsonPropertyName("tag_id")]
-    public long TagId { get; set; }
+    [JsonPropertyName("tag_code")]
+    public string TagCode { get; set; } = string.Empty;
 
     [JsonPropertyName("tag_name")]
     public string TagName { get; set; } = string.Empty;

SPMS.Application/DTOs/Tag/UpdateTagRequestDto.cs

@@ -6,8 +6,8 @@ namespace SPMS.Application.DTOs.Tag;
 public class UpdateTagRequestDto
 {
     [Required]
-    [JsonPropertyName("tag_id")]
-    public long TagId { get; set; }
+    [JsonPropertyName("tag_code")]
+    public string TagCode { get; set; } = string.Empty;
 
     [MaxLength(200)]
     [JsonPropertyName("description")]

SPMS.Application/Interfaces/ITagService.cs

@@ -6,6 +6,6 @@ public interface ITagService
 {
     Task<TagListResponseDto> GetListAsync(long? scopeServiceId, TagListRequestDto request);
     Task<TagResponseDto> CreateAsync(long adminId, CreateTagRequestDto request);
-    Task<TagResponseDto> UpdateAsync(UpdateTagRequestDto request);
-    Task DeleteAsync(DeleteTagRequestDto request);
+    Task<TagResponseDto> UpdateAsync(long serviceId, UpdateTagRequestDto request);
+    Task DeleteAsync(long serviceId, DeleteTagRequestDto request);
 }

SPMS.Application/Services/DeviceService.cs

@@ -12,15 +12,18 @@ namespace SPMS.Application.Services;
 public class DeviceService : IDeviceService
 {
     private readonly IDeviceRepository _deviceRepository;
+    private readonly ITagRepository _tagRepository;
     private readonly IUnitOfWork _unitOfWork;
     private readonly ITokenCacheService _tokenCache;
 
     public DeviceService(
         IDeviceRepository deviceRepository,
+        ITagRepository tagRepository,
         IUnitOfWork unitOfWork,
         ITokenCacheService tokenCache)
     {
         _deviceRepository = deviceRepository;
+        _tagRepository = tagRepository;
         _unitOfWork = unitOfWork;
         _tokenCache = tokenCache;
     }
@@ -80,7 +83,7 @@ public class DeviceService : IDeviceService
             Model = device.DeviceModel,
             PushAgreed = device.PushAgreed,
             MarketingAgreed = device.MarketingAgreed,
-            Tags = ParseTags(device.Tags),
+            Tags = await ConvertTagIdsToCodesAsync(device.Tags, serviceId),
             IsActive = device.IsActive,
             LastActiveAt = device.UpdatedAt,
             CreatedAt = device.CreatedAt
@@ -138,13 +141,30 @@ public class DeviceService : IDeviceService
         if (!string.IsNullOrWhiteSpace(request.Platform))
             platform = ParsePlatform(request.Platform);
 
+        // tag_code → tag_id 변환
+        List<long>? tagIds = null;
+        if (request.Tags != null && request.Tags.Count > 0 && serviceId.HasValue)
+        {
+            var tags = await _tagRepository.GetByTagCodesAndServiceAsync(request.Tags, serviceId.Value);
+            tagIds = tags.Select(t => t.Id).ToList();
+        }
+
         var (items, totalCount) = await _deviceRepository.GetPagedAsync(
             serviceId, request.Page, request.Size,
-            platform, request.PushAgreed, request.IsActive, request.Tags,
+            platform, request.PushAgreed, request.IsActive, tagIds,
             request.Keyword, request.MarketingAgreed);
 
         var totalPages = (int)Math.Ceiling((double)totalCount / request.Size);
 
+        // 응답의 tag_id → tag_code 일괄 변환을 위한 맵 구축
+        var allTagIds = new HashSet<long>();
+        foreach (var d in items)
+        {
+            var ids = ParseTagIds(d.Tags);
+            if (ids != null) allTagIds.UnionWith(ids);
+        }
+        var tagIdToCode = await BuildTagIdToCodeMapAsync(allTagIds, serviceId);
+
         return new DeviceListResponseDto
         {
             Items = items.Select(d => new DeviceSummaryDto
@@ -153,7 +173,7 @@ public class DeviceService : IDeviceService
                 Platform = d.Platform.ToString().ToLowerInvariant(),
                 Model = d.DeviceModel,
                 PushAgreed = d.PushAgreed,
-                Tags = ParseTags(d.Tags),
+                Tags = ConvertTagIdsToCodesSync(d.Tags, tagIdToCode),
                 LastActiveAt = d.UpdatedAt,
                 DeviceToken = d.DeviceToken,
                 ServiceName = d.Service?.ServiceName ?? string.Empty,
@@ -180,9 +200,17 @@ public class DeviceService : IDeviceService
         if (!string.IsNullOrWhiteSpace(request.Platform))
             platform = ParsePlatform(request.Platform);
 
+        // tag_code → tag_id 변환
+        List<long>? tagIds = null;
+        if (request.Tags != null && request.Tags.Count > 0 && serviceId.HasValue)
+        {
+            var tags = await _tagRepository.GetByTagCodesAndServiceAsync(request.Tags, serviceId.Value);
+            tagIds = tags.Select(t => t.Id).ToList();
+        }
+
         var items = await _deviceRepository.GetAllFilteredAsync(
             serviceId, platform, request.PushAgreed, request.IsActive,
-            request.Tags, request.Keyword, request.MarketingAgreed);
+            tagIds, request.Keyword, request.MarketingAgreed);
 
         using var workbook = new ClosedXML.Excel.XLWorkbook();
         var ws = workbook.Worksheets.Add("기기 목록");
@@ -235,7 +263,11 @@ public class DeviceService : IDeviceService
         if (device == null)
             throw new SpmsException(ErrorCodes.DeviceNotFound, "존재하지 않는 디바이스입니다.", 404);
 
-        device.Tags = JsonSerializer.Serialize(request.Tags);
+        // tag_code → tag_id 변환
+        var tags = await _tagRepository.GetByTagCodesAndServiceAsync(request.Tags, serviceId);
+        var tagIds = tags.Select(t => t.Id).ToList();
+
+        device.Tags = tagIds.Count > 0 ? JsonSerializer.Serialize(tagIds) : null;
         device.UpdatedAt = DateTime.UtcNow;
         _deviceRepository.Update(device);
         await _unitOfWork.SaveChangesAsync();
@@ -268,17 +300,58 @@ public class DeviceService : IDeviceService
         };
     }
 
-    private static List<int>? ParseTags(string? tagsJson)
+    private static List<long>? ParseTagIds(string? tagsJson)
     {
         if (string.IsNullOrWhiteSpace(tagsJson))
             return null;
         try
         {
-            return JsonSerializer.Deserialize<List<int>>(tagsJson);
+            return JsonSerializer.Deserialize<List<long>>(tagsJson);
         }
         catch
         {
             return null;
         }
     }
+
+    /// <summary>
+    /// DB에 저장된 tag_id JSON을 tag_code 목록으로 변환 (단일 디바이스용)
+    /// </summary>
+    private async Task<List<string>?> ConvertTagIdsToCodesAsync(string? tagsJson, long serviceId)
+    {
+        var tagIds = ParseTagIds(tagsJson);
+        if (tagIds == null || tagIds.Count == 0)
+            return null;
+
+        var tags = await _tagRepository.FindAsync(t => t.ServiceId == serviceId && tagIds.Contains(t.Id));
+        return tags.Select(t => t.TagCode).ToList();
+    }
+
+    /// <summary>
+    /// 미리 구축한 tagId→tagCode 맵을 사용하여 동기 변환 (목록 조회용)
+    /// </summary>
+    private static List<string>? ConvertTagIdsToCodesSync(string? tagsJson, Dictionary<long, string> tagIdToCode)
+    {
+        var tagIds = ParseTagIds(tagsJson);
+        if (tagIds == null || tagIds.Count == 0)
+            return null;
+
+        return tagIds
+            .Where(id => tagIdToCode.ContainsKey(id))
+            .Select(id => tagIdToCode[id])
+            .ToList();
+    }
+
+    /// <summary>
+    /// tag_id 집합으로부터 tag_id → tag_code 매핑 딕셔너리 구축
+    /// </summary>
+    private async Task<Dictionary<long, string>> BuildTagIdToCodeMapAsync(HashSet<long> tagIds, long? serviceId)
+    {
+        if (tagIds.Count == 0)
+            return new Dictionary<long, string>();
+
+        var tagIdList = tagIds.ToList();
+        var tags = await _tagRepository.FindAsync(t => tagIdList.Contains(t.Id));
+        return tags.ToDictionary(t => t.Id, t => t.TagCode);
+    }
 }

SPMS.Application/Services/TagService.cs

@@ -1,3 +1,4 @@
+using System.Security.Cryptography;
 using System.Text.Json;
 using SPMS.Application.DTOs.Notice;
 using SPMS.Application.DTOs.Tag;
@@ -17,6 +18,8 @@ public class TagService : ITagService
     private readonly IUnitOfWork _unitOfWork;
 
     private const int MaxTagsPerService = 10;
+    private const string Alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
+    private const int TagCodeLength = 4;
 
     public TagService(
         ITagRepository tagRepository,
@@ -32,7 +35,6 @@ public class TagService : ITagService
 
     public async Task<TagListResponseDto> GetListAsync(long? scopeServiceId, TagListRequestDto request)
     {
-        // scopeServiceId가 있으면 해당 서비스만, request.ServiceId도 추가 필터
         var effectiveServiceId = scopeServiceId ?? request.ServiceId;
 
         var (items, totalCount) = await _tagRepository.GetTagListAsync(
@@ -58,7 +60,7 @@ public class TagService : ITagService
             Items = items.Select(t => new TagSummaryDto
             {
                 TagIndex = serviceTagOrders[t.ServiceId].IndexOf(t.Id) + 1,
-                TagId = t.Id,
+                TagCode = t.TagCode,
                 TagName = t.Name,
                 Description = t.Description,
                 ServiceId = t.ServiceId,
@@ -93,9 +95,13 @@ public class TagService : ITagService
         if (currentCount >= MaxTagsPerService)
             throw new SpmsException(ErrorCodes.TagLimitExceeded, $"서비스당 태그는 최대 {MaxTagsPerService}개까지 생성할 수 있습니다.");
 
+        // TagCode 생성
+        var tagCode = await GenerateUniqueTagCodeAsync(request.ServiceId);
+
         var tag = new Tag
         {
             ServiceId = request.ServiceId,
+            TagCode = tagCode,
             Name = request.TagName,
             Description = request.Description,
             CreatedAt = DateTime.UtcNow,
@@ -107,7 +113,7 @@ public class TagService : ITagService
 
         return new TagResponseDto
         {
-            TagId = tag.Id,
+            TagCode = tag.TagCode,
             TagName = tag.Name,
             Description = tag.Description,
             ServiceId = tag.ServiceId,
@@ -117,9 +123,9 @@ public class TagService : ITagService
         };
     }
 
-    public async Task<TagResponseDto> UpdateAsync(UpdateTagRequestDto request)
+    public async Task<TagResponseDto> UpdateAsync(long serviceId, UpdateTagRequestDto request)
     {
-        var tag = await _tagRepository.GetByIdWithServiceAsync(request.TagId);
+        var tag = await _tagRepository.GetByTagCodeAndServiceAsync(request.TagCode, serviceId);
         if (tag == null)
             throw new SpmsException(ErrorCodes.TagNotFound, "태그를 찾을 수 없습니다.", 404);
 
@@ -131,7 +137,7 @@ public class TagService : ITagService
 
         return new TagResponseDto
         {
-            TagId = tag.Id,
+            TagCode = tag.TagCode,
             TagName = tag.Name,
             Description = tag.Description,
             ServiceId = tag.ServiceId,
@@ -141,9 +147,9 @@ public class TagService : ITagService
         };
     }
 
-    public async Task DeleteAsync(DeleteTagRequestDto request)
+    public async Task DeleteAsync(long serviceId, DeleteTagRequestDto request)
     {
-        var tag = await _tagRepository.GetByIdWithServiceAsync(request.TagId);
+        var tag = await _tagRepository.GetByTagCodeAndServiceAsync(request.TagCode, serviceId);
         if (tag == null)
             throw new SpmsException(ErrorCodes.TagNotFound, "태그를 찾을 수 없습니다.", 404);
 
@@ -152,11 +158,11 @@ public class TagService : ITagService
         try
         {
             // 해당 태그를 참조하는 디바이스의 Tags에서 tagId 제거
-            var devices = await _deviceRepository.GetDevicesByTagIdAsync(request.TagId);
+            var devices = await _deviceRepository.GetDevicesByTagIdAsync(tag.Id);
             foreach (var device in devices)
             {
-                var tagList = JsonSerializer.Deserialize<List<int>>(device.Tags!) ?? new();
-                tagList.Remove((int)request.TagId);
+                var tagList = JsonSerializer.Deserialize<List<long>>(device.Tags!) ?? new();
+                tagList.Remove(tag.Id);
                 device.Tags = tagList.Count > 0 ? JsonSerializer.Serialize(tagList) : null;
                 device.UpdatedAt = DateTime.UtcNow;
                 _deviceRepository.Update(device);
@@ -173,4 +179,29 @@ public class TagService : ITagService
             throw;
         }
     }
+
+    private async Task<string> GenerateUniqueTagCodeAsync(long serviceId)
+    {
+        var buffer = new byte[TagCodeLength];
+
+        for (var attempt = 0; attempt < 10; attempt++)
+        {
+            using (var rng = RandomNumberGenerator.Create())
+            {
+                rng.GetBytes(buffer);
+            }
+
+            var code = new char[TagCodeLength];
+            for (var i = 0; i < TagCodeLength; i++)
+            {
+                code[i] = Alphabet[buffer[i] % Alphabet.Length];
+            }
+
+            var tagCode = new string(code);
+            if (!await _tagRepository.TagCodeExistsInServiceAsync(serviceId, tagCode))
+                return tagCode;
+        }
+
+        throw new SpmsException(ErrorCodes.InternalError, "태그 코드 생성에 실패했습니다. 잠시 후 다시 시도해주세요.", 500);
+    }
 }

SPMS.Domain/Entities/Tag.cs

@@ -3,6 +3,7 @@ namespace SPMS.Domain.Entities;
 public class Tag : BaseEntity
 {
     public long ServiceId { get; set; }
+    public string TagCode { get; set; } = string.Empty;
     public string Name { get; set; } = string.Empty;
     public string? Description { get; set; }
     public DateTime CreatedAt { get; set; }

SPMS.Domain/Interfaces/IDeviceRepository.cs

@@ -12,12 +12,12 @@ public interface IDeviceRepository : IRepository<Device>
     Task<(IReadOnlyList<Device> Items, int TotalCount)> GetPagedAsync(
         long? serviceId, int page, int size,
         Platform? platform = null, bool? pushAgreed = null,
-        bool? isActive = null, List<int>? tags = null,
+        bool? isActive = null, List<long>? tagIds = null,
         string? keyword = null, bool? marketingAgreed = null);
     Task<IReadOnlyList<Device>> GetAllFilteredAsync(
         long? serviceId,
         Platform? platform = null, bool? pushAgreed = null,
-        bool? isActive = null, List<int>? tags = null,
+        bool? isActive = null, List<long>? tagIds = null,
         string? keyword = null, bool? marketingAgreed = null);
     Task<Dictionary<long, int>> GetDeviceCountsByTagIdsAsync(IEnumerable<long> tagIds);
     Task<IReadOnlyList<Device>> GetDevicesByTagIdAsync(long tagId);

SPMS.Domain/Interfaces/ITagRepository.cs

@@ -5,8 +5,11 @@ namespace SPMS.Domain.Interfaces;
 public interface ITagRepository : IRepository<Tag>
 {
     Task<Tag?> GetByIdWithServiceAsync(long id);
+    Task<Tag?> GetByTagCodeAndServiceAsync(string tagCode, long serviceId);
     Task<bool> ExistsInServiceAsync(long serviceId, string name);
+    Task<bool> TagCodeExistsInServiceAsync(long serviceId, string tagCode);
     Task<(IReadOnlyList<Tag> Items, int TotalCount)> GetTagListAsync(
         long? serviceId, string? keyword, int page, int size);
     Task<int> CountByServiceAsync(long serviceId);
+    Task<IReadOnlyList<Tag>> GetByTagCodesAndServiceAsync(IEnumerable<string> tagCodes, long serviceId);
 }

SPMS.Infrastructure/Migrations/20260302070717_AddTagCode.cs

@@ -0,0 +1,53 @@
+using Microsoft.EntityFrameworkCore.Migrations;
+
+#nullable disable
+
+namespace SPMS.Infrastructure.Migrations
+{
+    /// <inheritdoc />
+    public partial class AddTagCode : Migration
+    {
+        /// <inheritdoc />
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.AddColumn<string>(
+                name: "TagCode",
+                table: "Tag",
+                type: "varchar(4)",
+                maxLength: 4,
+                nullable: false,
+                defaultValue: "")
+                .Annotation("MySql:CharSet", "utf8mb4");
+
+            // 기존 태그에 4자리 랜덤 코드 할당 (서비스별 유니크)
+            migrationBuilder.Sql(@"
+                UPDATE Tag
+                SET TagCode = CONCAT(
+                    SUBSTRING('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789', FLOOR(1 + RAND() * 62), 1),
+                    SUBSTRING('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789', FLOOR(1 + RAND() * 62), 1),
+                    SUBSTRING('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789', FLOOR(1 + RAND() * 62), 1),
+                    SUBSTRING('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789', FLOOR(1 + RAND() * 62), 1)
+                )
+                WHERE TagCode = '';
+            ");
+
+            migrationBuilder.CreateIndex(
+                name: "IX_Tag_ServiceId_TagCode",
+                table: "Tag",
+                columns: new[] { "ServiceId", "TagCode" },
+                unique: true);
+        }
+
+        /// <inheritdoc />
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropIndex(
+                name: "IX_Tag_ServiceId_TagCode",
+                table: "Tag");
+
+            migrationBuilder.DropColumn(
+                name: "TagCode",
+                table: "Tag");
+        }
+    }
+}

SPMS.Infrastructure/Migrations/AppDbContextModelSnapshot.cs

@@ -914,6 +914,11 @@ namespace SPMS.Infrastructure.Migrations
                     b.Property<long>("ServiceId")
                         .HasColumnType("bigint");
 
+                    b.Property<string>("TagCode")
+                        .IsRequired()
+                        .HasMaxLength(4)
+                        .HasColumnType("varchar(4)");
+
                     b.Property<DateTime?>("UpdatedAt")
                         .HasColumnType("datetime(6)");
 
@@ -924,6 +929,9 @@ namespace SPMS.Infrastructure.Migrations
                     b.HasIndex("ServiceId", "Name")
                         .IsUnique();
 
+                    b.HasIndex("ServiceId", "TagCode")
+                        .IsUnique();
+
                     b.ToTable("Tag", (string)null);
                 });
 

SPMS.Infrastructure/Persistence/Configurations/TagConfiguration.cs

@@ -13,6 +13,7 @@ public class TagConfiguration : IEntityTypeConfiguration<Tag>
         builder.HasKey(e => e.Id);
         builder.Property(e => e.Id).ValueGeneratedOnAdd();
 
+        builder.Property(e => e.TagCode).HasMaxLength(4).IsRequired();
         builder.Property(e => e.Name).HasMaxLength(50).IsRequired();
         builder.Property(e => e.Description).HasMaxLength(200);
         builder.Property(e => e.CreatedAt).IsRequired();
@@ -30,5 +31,6 @@ public class TagConfiguration : IEntityTypeConfiguration<Tag>
             .OnDelete(DeleteBehavior.Restrict);
 
         builder.HasIndex(e => new { e.ServiceId, e.Name }).IsUnique();
+        builder.HasIndex(e => new { e.ServiceId, e.TagCode }).IsUnique();
     }
 }

SPMS.Infrastructure/Persistence/Repositories/DeviceRepository.cs

@@ -34,7 +34,7 @@ public class DeviceRepository : Repository<Device>, IDeviceRepository
     public async Task<(IReadOnlyList<Device> Items, int TotalCount)> GetPagedAsync(
         long? serviceId, int page, int size,
         Platform? platform = null, bool? pushAgreed = null,
-        bool? isActive = null, List<int>? tags = null,
+        bool? isActive = null, List<long>? tagIds = null,
         string? keyword = null, bool? marketingAgreed = null)
     {
         IQueryable<Device> query = _dbSet.Include(d => d.Service);
@@ -63,11 +63,11 @@ public class DeviceRepository : Repository<Device>, IDeviceRepository
                 query = query.Where(d => d.DeviceToken.Contains(trimmed));
         }
 
-        if (tags != null && tags.Count > 0)
+        if (tagIds != null && tagIds.Count > 0)
         {
-            foreach (var tag in tags)
+            foreach (var tagId in tagIds)
             {
-                var tagStr = tag.ToString();
+                var tagStr = tagId.ToString();
                 query = query.Where(d => d.Tags != null && EF.Functions.Like(d.Tags, $"%{tagStr}%"));
             }
         }
@@ -86,7 +86,7 @@ public class DeviceRepository : Repository<Device>, IDeviceRepository
     public async Task<IReadOnlyList<Device>> GetAllFilteredAsync(
         long? serviceId,
         Platform? platform = null, bool? pushAgreed = null,
-        bool? isActive = null, List<int>? tags = null,
+        bool? isActive = null, List<long>? tagIds = null,
         string? keyword = null, bool? marketingAgreed = null)
     {
         IQueryable<Device> query = _dbSet.Include(d => d.Service);
@@ -115,11 +115,11 @@ public class DeviceRepository : Repository<Device>, IDeviceRepository
                 query = query.Where(d => d.DeviceToken.Contains(trimmed));
         }
 
-        if (tags != null && tags.Count > 0)
+        if (tagIds != null && tagIds.Count > 0)
         {
-            foreach (var tag in tags)
+            foreach (var tagId in tagIds)
             {
-                var tagStr = tag.ToString();
+                var tagStr = tagId.ToString();
                 query = query.Where(d => d.Tags != null && EF.Functions.Like(d.Tags, $"%{tagStr}%"));
             }
         }

SPMS.Infrastructure/Persistence/Repositories/TagRepository.cs

@@ -13,9 +13,17 @@ public class TagRepository : Repository<Tag>, ITagRepository
             .Include(t => t.Service)
             .FirstOrDefaultAsync(t => t.Id == id);
 
+    public async Task<Tag?> GetByTagCodeAndServiceAsync(string tagCode, long serviceId)
+        => await _dbSet
+            .Include(t => t.Service)
+            .FirstOrDefaultAsync(t => t.TagCode == tagCode && t.ServiceId == serviceId);
+
     public async Task<bool> ExistsInServiceAsync(long serviceId, string name)
         => await _dbSet.AnyAsync(t => t.ServiceId == serviceId && t.Name == name);
 
+    public async Task<bool> TagCodeExistsInServiceAsync(long serviceId, string tagCode)
+        => await _dbSet.AnyAsync(t => t.ServiceId == serviceId && t.TagCode == tagCode);
+
     public async Task<(IReadOnlyList<Tag> Items, int TotalCount)> GetTagListAsync(
         long? serviceId, string? keyword, int page, int size)
     {
@@ -43,4 +51,12 @@ public class TagRepository : Repository<Tag>, ITagRepository
 
     public async Task<int> CountByServiceAsync(long serviceId)
         => await _dbSet.CountAsync(t => t.ServiceId == serviceId);
+
+    public async Task<IReadOnlyList<Tag>> GetByTagCodesAndServiceAsync(IEnumerable<string> tagCodes, long serviceId)
+    {
+        var codeList = tagCodes.ToList();
+        return await _dbSet
+            .Where(t => t.ServiceId == serviceId && codeList.Contains(t.TagCode))
+            .ToListAsync();
+    }
 }

SPMS.Infrastructure/Workers/PushWorker.cs

@@ -149,6 +149,7 @@ public class PushWorker : BackgroundService
         using var scope = _scopeFactory.CreateScope();
         var serviceRepo = scope.ServiceProvider.GetRequiredService<IServiceRepository>();
         var deviceRepo = scope.ServiceProvider.GetRequiredService<IDeviceRepository>();
+        var tagRepo = scope.ServiceProvider.GetRequiredService<ITagRepository>();
         var unitOfWork = scope.ServiceProvider.GetRequiredService<IUnitOfWork>();
 
         // 서비스 조회
@@ -161,7 +162,7 @@ public class PushWorker : BackgroundService
         }
 
         // [2] send_type별 대상 Device 조회
-        var devices = await ResolveDevicesAsync(deviceRepo, pushMessage, ct);
+        var devices = await ResolveDevicesAsync(deviceRepo, tagRepo, pushMessage, ct);
         if (devices.Count == 0)
         {
             _logger.LogInformation("발송 대상 없음: requestId={RequestId}", pushMessage.RequestId);
@@ -296,7 +297,7 @@ public class PushWorker : BackgroundService
     }
 
     private async Task<List<Device>> ResolveDevicesAsync(
-        IDeviceRepository deviceRepo, PushMessageDto message, CancellationToken ct)
+        IDeviceRepository deviceRepo, ITagRepository tagRepo, PushMessageDto message, CancellationToken ct)
     {
         var sendType = message.SendType.ToLowerInvariant();
 
@@ -346,15 +347,21 @@ public class PushWorker : BackgroundService
 
             case "group":
             {
-                var tags = ParseTags(message.Target);
-                if (tags.Count == 0) return [];
+                // tag_code(string) 목록 파싱
+                var tagCodes = ParseTags(message.Target);
+                if (tagCodes.Count == 0) return [];
+
+                // tag_code → tag_id 변환
+                var tags = await tagRepo.GetByTagCodesAndServiceAsync(tagCodes, message.ServiceId);
+                var tagIdStrings = tags.Select(t => t.Id.ToString()).ToHashSet();
+                if (tagIdStrings.Count == 0) return [];
 
                 var allDevices = await deviceRepo.FindAsync(
                     d => d.ServiceId == message.ServiceId && d.IsActive && d.PushAgreed);
 
                 return allDevices
                     .Where(d => !string.IsNullOrEmpty(d.Tags) &&
-                                tags.Any(tag => d.Tags.Contains(tag)))
+                                tagIdStrings.Any(tagIdStr => d.Tags.Contains(tagIdStr)))
                     .ToList();
             }
 
@@ -396,9 +403,23 @@ public class PushWorker : BackgroundService
 
         try
         {
-            if (target.Value.Value.ValueKind == JsonValueKind.Array)
+            var element = target.Value.Value;
+
+            // { tags: [...], match: "or" } 형태
+            if (element.ValueKind == JsonValueKind.Object &&
+                element.TryGetProperty("tags", out var tagsElement) &&
+                tagsElement.ValueKind == JsonValueKind.Array)
             {
-                return target.Value.Value.EnumerateArray()
+                return tagsElement.EnumerateArray()
+                    .Where(e => e.ValueKind == JsonValueKind.String)
+                    .Select(e => e.GetString()!)
+                    .ToList();
+            }
+
+            // 직접 배열 형태 (호환)
+            if (element.ValueKind == JsonValueKind.Array)
+            {
+                return element.EnumerateArray()
                     .Where(e => e.ValueKind == JsonValueKind.String)
                     .Select(e => e.GetString()!)
                     .ToList();