[backend/api] Add PaginationWrapper<TData> & associated helper methods

Iceshrimp.Backend/Controllers/Shared/Attributes/LinkPaginationAttribute.cs

@@ -7,7 +7,11 @@ using Microsoft.AspNetCore.Mvc.Filters;
 
 namespace Iceshrimp.Backend.Controllers.Shared.Attributes;
 
-public class LinkPaginationAttribute(int defaultLimit, int maxLimit, bool offset = false) : ActionFilterAttribute
+public class LinkPaginationAttribute(
+	int defaultLimit,
+	int maxLimit,
+	bool offset = false
+) : ActionFilterAttribute, IPaginationAttribute
 {
 	public int DefaultLimit => defaultLimit;
 	public int MaxLimit     => maxLimit;
@@ -75,6 +79,12 @@ public class LinkPaginationAttribute(int defaultLimit, int maxLimit, bool offset
 	}
 }
 
+public interface IPaginationAttribute
+{
+	public int  DefaultLimit { get; }
+	public int  MaxLimit     { get; }
+}
+
 public static class HttpContextExtensions
 {
 	private const string Key = "link-pagination";

Iceshrimp.Backend/Controllers/Web/NoteController.cs

@@ -13,6 +13,7 @@ using Iceshrimp.Backend.Core.Helpers;
 using Iceshrimp.Backend.Core.Middleware;
 using Iceshrimp.Backend.Core.Services;
 using Iceshrimp.Shared.Schemas.Web;
+using Microsoft.AspNetCore.Http.Extensions;
 using Microsoft.AspNetCore.Http.HttpResults;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.RateLimiting;
@@ -217,10 +218,10 @@ public class NoteController(
 	[HttpGet("{id}/likes")]
 	[Authenticate]
 	[Authorize]
-	[LinkPagination(20, 40)]
+	[RestPagination(20, 40)]
 	[ProducesResults(HttpStatusCode.OK)]
 	[ProducesErrors(HttpStatusCode.NotFound)]
-	public async Task<IEnumerable<UserResponse>> GetNoteLikes(string id, PaginationQuery pq)
+	public async Task<PaginationWrapper<IEnumerable<UserResponse>>> GetNoteLikes(string id, PaginationQuery pq)
 	{
 		var user = HttpContext.GetUser();
 		var note = await db.Notes
@@ -236,8 +237,8 @@ public class NoteController(
 		                    .Wrap(p => p.User)
 		                    .ToListAsync();
 
-		HttpContext.SetPaginationData(users);
+		var res = await userRenderer.RenderMany(users.Select(p => p.Entity));
-		return await userRenderer.RenderMany(users.Select(p => p.Entity));
+		return HttpContext.CreatePaginationWrapper(pq, users, res);
 	}
 
 	[HttpPost("{id}/renote")]

Iceshrimp.Backend/Core/Extensions/HttpContextExtensions.cs

@@ -0,0 +1,50 @@
+using Iceshrimp.Backend.Controllers.Shared.Attributes;
+using Iceshrimp.Backend.Controllers.Shared.Schemas;
+using Iceshrimp.Backend.Core.Database;
+using Iceshrimp.Backend.Core.Middleware;
+using Iceshrimp.Shared.Schemas.Web;
+using Microsoft.AspNetCore.Http.Extensions;
+
+namespace Iceshrimp.Backend.Core.Extensions;
+
+public static partial class HttpContextExtensions
+{
+	public static PaginationWrapper<TData> CreatePaginationWrapper<TData>(
+		this HttpContext ctx, PaginationQuery query, IEnumerable<IEntity> paginationData, TData data
+	)
+	{
+		var attr = ctx.GetEndpoint()?.Metadata.GetMetadata<RestPaginationAttribute>();
+		if (attr == null) throw new Exception("Route doesn't have a RestPaginationAttribute");
+
+		var limit = Math.Min(query.Limit ?? attr.DefaultLimit, attr.MaxLimit);
+		if (limit < 1) throw GracefulException.BadRequest("Limit cannot be less than 1");
+
+		var ids = paginationData.Select(p => p.Id).ToList();
+		if (query.MinId != null) ids.Reverse();
+
+		var next = ids.Count >= limit ? new QueryBuilder { { "max_id", ids.Last() } } : null;
+		var prev = ids.Count > 0 ? new QueryBuilder { { "min_id", ids.First() } } : null;
+
+		var links = new PaginationData
+		{
+			Limit = limit,
+			Next  = next?.ToQueryString().ToString(),
+			Prev  = prev?.ToQueryString().ToString()
+		};
+
+		return new PaginationWrapper<TData> { Data = data, Links = links };
+	}
+
+	public static PaginationWrapper<TData> CreatePaginationWrapper<TData>(
+		this HttpContext ctx, PaginationQuery query, TData data
+	) where TData : IEnumerable<IEntity>
+	{
+		return CreatePaginationWrapper(ctx, query, data, data);
+	}
+}
+
+public class RestPaginationAttribute(int defaultLimit, int maxLimit) : Attribute, IPaginationAttribute
+{
+	public int DefaultLimit => defaultLimit;
+	public int MaxLimit     => maxLimit;
+}

Iceshrimp.Backend/Core/Extensions/QueryableExtensions.cs

@@ -276,13 +276,11 @@ public static class QueryableExtensions
 		ControllerContext context
 	) where T : IEntity
 	{
-		var filter = context.ActionDescriptor.FilterDescriptors.Select(p => p.Filter)
+		var attr = context.HttpContext.GetEndpoint()?.Metadata.GetMetadata<IPaginationAttribute>();
-		                    .OfType<LinkPaginationAttribute>()
+		if (attr == null)
-		                    .FirstOrDefault();
+			throw new Exception("Route doesn't have a IPaginationAttribute");
-		if (filter == null)
-			throw new Exception("Route doesn't have a LinkPaginationAttribute");
 
-		return Paginate(query, pq, filter.DefaultLimit, filter.MaxLimit);
+		return Paginate(query, pq, attr.DefaultLimit, attr.MaxLimit);
 	}
 
 	public static IQueryable<T> PaginateByOffset<T>(
@@ -304,13 +302,11 @@ public static class QueryableExtensions
 		ControllerContext context
 	) where T : IEntity
 	{
-		var filter = context.ActionDescriptor.FilterDescriptors.Select(p => p.Filter)
+		var attr = context.HttpContext.GetEndpoint()?.Metadata.GetMetadata<IPaginationAttribute>();
-		                    .OfType<LinkPaginationAttribute>()
+		if (attr == null)
-		                    .FirstOrDefault();
+			throw new Exception("Route doesn't have a IPaginationAttribute");
-		if (filter == null)
-			throw new Exception("Route doesn't have a LinkPaginationAttribute");
 
-		return PaginateByOffset(query, pq, filter.DefaultLimit, filter.MaxLimit);
+		return PaginateByOffset(query, pq, attr.DefaultLimit, attr.MaxLimit);
 	}
 
 	public static IQueryable<T> Paginate<T>(
@@ -320,13 +316,11 @@ public static class QueryableExtensions
 		ControllerContext context
 	) where T : IEntity
 	{
-		var filter = context.ActionDescriptor.FilterDescriptors.Select(p => p.Filter)
+		var attr = context.HttpContext.GetEndpoint()?.Metadata.GetMetadata<IPaginationAttribute>();
-		                    .OfType<LinkPaginationAttribute>()
+		if (attr == null)
-		                    .FirstOrDefault();
+			throw new Exception("Route doesn't have a IPaginationAttribute");
-		if (filter == null)
-			throw new Exception("Route doesn't have a LinkPaginationAttribute");
 
-		return Paginate(query, predicate, pq, filter.DefaultLimit, filter.MaxLimit);
+		return Paginate(query, predicate, pq, attr.DefaultLimit, attr.MaxLimit);
 	}
 
 	public static IQueryable<T> Paginate<T>(
@@ -336,13 +330,11 @@ public static class QueryableExtensions
 		ControllerContext context
 	) where T : IEntity
 	{
-		var filter = context.ActionDescriptor.FilterDescriptors.Select(p => p.Filter)
+		var attr = context.HttpContext.GetEndpoint()?.Metadata.GetMetadata<IPaginationAttribute>();
-		                    .OfType<LinkPaginationAttribute>()
+		if (attr == null)
-		                    .FirstOrDefault();
+			throw new Exception("Route doesn't have a IPaginationAttribute");
-		if (filter == null)
-			throw new Exception("Route doesn't have a LinkPaginationAttribute");
 
-		return Paginate(query, predicate, pq, filter.DefaultLimit, filter.MaxLimit);
+		return Paginate(query, predicate, pq, attr.DefaultLimit, attr.MaxLimit);
 	}
 
 	public static IQueryable<T> Paginate<T>(
@@ -351,13 +343,11 @@ public static class QueryableExtensions
 		ControllerContext context
 	) where T : IEntity
 	{
-		var filter = context.ActionDescriptor.FilterDescriptors.Select(p => p.Filter)
+		var attr = context.HttpContext.GetEndpoint()?.Metadata.GetMetadata<IPaginationAttribute>();
-		                    .OfType<LinkPaginationAttribute>()
+		if (attr == null)
-		                    .FirstOrDefault();
+			throw new Exception("Route doesn't have a IPaginationAttribute");
-		if (filter == null)
-			throw new Exception("Route doesn't have a LinkPaginationAttribute");
 
-		return Paginate(query, pq, filter.DefaultLimit, filter.MaxLimit);
+		return Paginate(query, pq, attr.DefaultLimit, attr.MaxLimit);
 	}
 
 	public static IQueryable<EntityWrapper<TResult>> Wrap<TSource, TResult>(

Iceshrimp.Backend/Core/Extensions/ServiceExtensions.cs

@@ -365,7 +365,7 @@ public static class ServiceExtensions
 	}
 }
 
-public static class HttpContextExtensions
+public static partial class HttpContextExtensions
 {
 	public static string GetRateLimitPartition(this HttpContext ctx, bool includeRoute) =>
 		(includeRoute ? ctx.Request.Path.ToString() + "#" : "") + (GetRateLimitPartitionInternal(ctx) ?? "");

Iceshrimp.Shared/Schemas/Web/PaginationWrapper.cs

@@ -0,0 +1,14 @@
+namespace Iceshrimp.Shared.Schemas.Web;
+
+public class PaginationWrapper<TData>
+{
+	public required PaginationData Links { get; set; }
+	public required TData          Data  { get; set; }
+}
+
+public class PaginationData
+{
+	public required int     Limit { get; set; }
+	public          string? Next  { get; set; }
+	public          string? Prev  { get; set; }
+}