feat(paging): add paging via X.PagedList

Author: jaredcnance

src/JsonApiDotNetCore/Configuration/JsonApiOptions.cs

@@ -3,5 +3,6 @@ namespace JsonApiDotNetCore.Configuration
     public class JsonApiOptions
     {
         public string Namespace { get; set; }
+        public int DefaultPageSize { get; set; }
     }
 }

src/JsonApiDotNetCore/Controllers/JsonApiController.cs

@@ -52,16 +52,19 @@ public JsonApiController(
         }
 
         [HttpGet]
-        public virtual IActionResult Get()
+        public virtual async Task<IActionResult> GetAsync()
         {
             var entities = _entities.Get();
 
             entities = ApplySortAndFilterQuery(entities);
 
-            if(_jsonApiContext.QuerySet != null)
+            if (_jsonApiContext.QuerySet != null)
                 entities = IncludeRelationships(entities, _jsonApiContext.QuerySet.IncludedRelationships);
 
-            return Ok(entities);
+            // pagination should be done last since it will execute the query
+            var pagedEntities = await ApplyPageQueryAsync(entities);
+
+            return Ok(pagedEntities);
         }
 
         [HttpGet("{id}")]
@@ -142,12 +145,6 @@ public virtual async Task<IActionResult> PatchAsync(TId id, [FromBody] T entity)
             return Ok(updatedEntity);
         }
 
-        // [HttpPatch("{id}/{relationship}")]
-        // public virtual IActionResult PatchRelationship(int id, string relation) 
-        // {
-        //     return Ok("Patch Id/relationship");
-        // }
-
         [HttpDelete("{id}")]
         public virtual async Task<IActionResult> DeleteAsync(TId id)
         {
@@ -159,12 +156,6 @@ public virtual async Task<IActionResult> DeleteAsync(TId id)
             return Ok();
         }
 
-        // [HttpDelete("{id}/{relationship}")]
-        // public virtual IActionResult Delete(int id, string relation) 
-        // {
-        //     return Ok("Delete Id/relationship");
-        // }
-
         private IQueryable<T> ApplySortAndFilterQuery(IQueryable<T> entities)
         {
             var query = _jsonApiContext.QuerySet;
@@ -179,6 +170,18 @@ private IQueryable<T> ApplySortAndFilterQuery(IQueryable<T> entities)
             return entities;
         }
 
+        private async Task<IEnumerable<T>> ApplyPageQueryAsync(IQueryable<T> entities)
+        {
+            if(_jsonApiContext.Options.DefaultPageSize == 0 && (_jsonApiContext.QuerySet == null || _jsonApiContext.QuerySet.PageQuery.PageSize == 0))
+                return entities;
+
+            var query = _jsonApiContext.QuerySet.PageQuery;
+            var pageNumber = query.PageOffset > 0 ? query.PageOffset : 1;
+            var pageSize = query.PageSize > 0 ? query.PageSize : _jsonApiContext.Options.DefaultPageSize;
+
+            return await _entities.PageAsync(entities, pageSize, pageNumber);
+        }
+
         private IQueryable<T> IncludeRelationships(IQueryable<T> entities, List<string> relationships)
         {
             _jsonApiContext.IncludedRelationships = relationships;

src/JsonApiDotNetCore/Data/DefaultEntityRepository.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading.Tasks;
@@ -9,6 +8,7 @@
 using JsonApiDotNetCore.Services;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.Extensions.Logging;
+using X.PagedList;
 
 namespace JsonApiDotNetCore.Data
 {
@@ -132,5 +132,10 @@ public IQueryable<TEntity> Include(IQueryable<TEntity> entities, string relation
             throw new JsonApiException("400", "Invalid relationship",
                 $"{entity.EntityName} does not have a relationship named {relationshipName}");
         }
+
+        public async Task<IEnumerable<TEntity>> PageAsync(IQueryable<TEntity> entities, int pageSize, int pageNumber)
+        {
+            return await entities.ToPagedListAsync(pageNumber, pageSize);
+        }
     }
 }

src/JsonApiDotNetCore/Data/IEntityRepository.cs

@@ -23,6 +23,8 @@ public interface IEntityRepository<TEntity, in TId>
 
         IQueryable<TEntity> Sort(IQueryable<TEntity> entities, List<SortQuery> sortQueries);
 
+        Task<IEnumerable<TEntity>> PageAsync(IQueryable<TEntity> entities, int pageSize, int pageNumber);
+
         Task<TEntity> GetAsync(TId id);
 
         Task<TEntity> GetAndIncludeAsync(TId id, string relationshipName);

src/JsonApiDotNetCore/Extensions/ServiceProviderExtensions.cs

@@ -30,25 +30,25 @@ public static void AddJsonApi<TContext>(this IServiceCollection services, Action
         private static void _addInternals<TContext>(IServiceCollection services, JsonApiOptions jsonApiOptions)
             where TContext : DbContext
         {
-            services.AddJsonApiInternals<TContext>();
+            services.AddJsonApiInternals<TContext>(jsonApiOptions);
             services.AddMvc()
                 .AddMvcOptions(opt => {
                     opt.Filters.Add(typeof(JsonApiExceptionFilter));
                     opt.SerializeAsJsonApi(jsonApiOptions);
                 });
         }
 
-        public static void AddJsonApiInternals<TContext>(this IServiceCollection services) 
+        public static void AddJsonApiInternals<TContext>(this IServiceCollection services, JsonApiOptions jsonApiOptions) 
             where TContext : DbContext
         {
             var contextGraphBuilder = new ContextGraphBuilder<TContext>();
             var contextGraph = contextGraphBuilder.Build();
 
             services.AddScoped(typeof(DbContext), typeof(TContext));
-
             services.AddScoped(typeof(IEntityRepository<>), typeof(DefaultEntityRepository<>));
             services.AddScoped(typeof(IEntityRepository<,>), typeof(DefaultEntityRepository<,>));
 
+            services.AddSingleton<JsonApiOptions>(jsonApiOptions);
             services.AddSingleton<IContextGraph>(contextGraph);
             services.AddScoped<IJsonApiContext,JsonApiContext>();
             services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

src/JsonApiDotNetCore/Internal/Query/PageQuery.cs

@@ -0,0 +1,8 @@
+namespace JsonApiDotNetCore.Internal.Query
+{
+    public class PageQuery
+    {
+       public int PageSize { get; set; }
+       public int PageOffset { get; set; }
+    }
+}

src/JsonApiDotNetCore/Internal/Query/QuerySet.cs

@@ -1,3 +1,4 @@
+using System;
 using System.Collections.Generic;
 using System.Linq;
 using JsonApiDotNetCore.Extensions;
@@ -14,9 +15,11 @@ public QuerySet(IJsonApiContext jsonApiContext, IQueryCollection query)
         {
             _jsonApiContext = jsonApiContext;
             BuildQuerySet(query);
+            PageQuery = new PageQuery();
         }
 
         public FilterQuery Filter { get; set; }
+        public PageQuery PageQuery { get; set; }
         public List<SortQuery> SortParameters { get; set; }
         public List<string> IncludedRelationships { get; set; }
 
@@ -40,6 +43,11 @@ private void BuildQuerySet(IQueryCollection query)
                 {
                     IncludedRelationships = ParseIncludedRelationships(pair.Value);
                 }
+
+                if(pair.Key.StartsWith("page"))
+                {
+                    PageQuery = ParsePageQuery(pair.Key, pair.Value);
+                }
             }
         }
 
@@ -55,6 +63,21 @@ private FilterQuery ParseFilterQuery(string key, string value)
             return new FilterQuery(attribute, value);
         }
 
+        private PageQuery ParsePageQuery(string key, string value)
+        {
+            // expected input = page[size]=10
+            //                  page[number]=1
+
+            var propertyName = key.Split('[', ']')[1];
+            
+            if(propertyName == "size")
+                PageQuery.PageSize = Convert.ToInt32(value);
+            else if (propertyName == "number")
+                PageQuery.PageOffset = Convert.ToInt32(value);
+
+            return PageQuery;
+        }
+
         // sort=id,name
         // sort=-id
         private List<SortQuery> ParseSortParameters(string value)

src/JsonApiDotNetCore/Services/IJsonApiContext.cs

@@ -1,11 +1,13 @@
 using System.Collections.Generic;
+using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Internal;
 using JsonApiDotNetCore.Internal.Query;
 
 namespace JsonApiDotNetCore.Services
 {
     public interface IJsonApiContext
     {
+        JsonApiOptions Options { get; set; }
         IJsonApiContext ApplyContext<T>();
         IContextGraph ContextGraph { get; set; }
         ContextEntity RequestEntity { get; set; }

src/JsonApiDotNetCore/Services/JsonApiContext.cs

@@ -1,6 +1,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using JsonApiDotNetCore.Builders;
+using JsonApiDotNetCore.Configuration;
 using JsonApiDotNetCore.Internal;
 using JsonApiDotNetCore.Internal.Query;
 using Microsoft.AspNetCore.Http;
@@ -12,12 +13,14 @@ public class JsonApiContext : IJsonApiContext
         private IHttpContextAccessor _httpContextAccessor;
         public JsonApiContext(
             IContextGraph contextGraph,
-            IHttpContextAccessor httpContextAccessor)
+            IHttpContextAccessor httpContextAccessor,
+            JsonApiOptions options)
         {
             ContextGraph = contextGraph;
             _httpContextAccessor = httpContextAccessor;
+            Options = options;
         }
-
+        public JsonApiOptions Options { get; set; }
         public IContextGraph ContextGraph { get; set; }
         public ContextEntity RequestEntity { get; set; }
         public string BasePath { get; set; }

src/JsonApiDotNetCore/project.json

@@ -9,7 +9,8 @@
     "Microsoft.AspNetCore.Routing": "1.1.0",
     "Microsoft.AspNetCore.Mvc": "1.1.0",
     "Microsoft.EntityFrameworkCore": "1.1.0",
-    "Microsoft.Extensions.Logging": "1.1.0"
+    "Microsoft.Extensions.Logging": "1.1.0",
+    "X.PagedList": "5.3.0.5300"
   },
 
   "frameworks": {

src/JsonApiDotNetCoreExample/Startup.cs

@@ -7,6 +7,10 @@
 using JsonApiDotNetCoreExample.Data;
 using Microsoft.EntityFrameworkCore;
 using JsonApiDotNetCore.Extensions;
+using Microsoft.AspNetCore.Http;
+using System.Threading.Tasks;
+using System.Reflection;
+using System;
 
 namespace JsonApiDotNetCoreExample
 {
@@ -31,7 +35,10 @@ public void ConfigureServices(IServiceCollection services)
                 options.UseNpgsql(_getDbConnectionString());
             }, ServiceLifetime.Transient);
 
-            services.AddJsonApi<AppDbContext>(opt => opt.Namespace = "api/v1");
+            services.AddJsonApi<AppDbContext>(opt => {
+                opt.Namespace = "api/v1";
+                opt.DefaultPageSize = 1;
+            });
         }
 
         public void Configure(
@@ -52,4 +59,4 @@ private string _getDbConnectionString()
             return _config["Data:DefaultConnection"];
         }
     }
-}
+}