Implementing eager fetching for Hql queries

src/Orchard.Web/Modules/Orchard.Projections/Orchard.Projections.csproj

@@ -130,6 +130,8 @@
     <Compile Include="Models\NavigationQueryPart.cs" />
     <Compile Include="Models\NavigationQueryPartRecord.cs" />
     <Compile Include="Models\QueryPart.cs" />
+    <Compile Include="Providers\Filters\ContentPartsForm.cs" />
+    <Compile Include="Providers\Filters\EagerFetchFilter.cs" />
     <Compile Include="Providers\Layouts\RawLayout.cs" />
     <Compile Include="Providers\Layouts\RawLayoutForms.cs" />
     <Compile Include="Providers\Layouts\RawShapes.cs" />

src/Orchard.Web/Modules/Orchard.Projections/Providers/Filters/ContentPartsForm.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Linq;
+using System.Web.Mvc;
+using Orchard.ContentManagement.MetaData;
+using Orchard.DisplayManagement;
+using Orchard.Forms.Services;
+using Orchard.Localization;
+
+namespace Orchard.Projections.Providers.Filters {
+    public class ContentPartsForm : IFormProvider {
+        private readonly IContentDefinitionManager _contentDefinitionManager;
+        protected dynamic Shape { get; set; }
+        public Localizer T { get; set; }
+
+        public ContentPartsForm(
+            IShapeFactory shapeFactory,
+            IContentDefinitionManager contentDefinitionManager) {
+            _contentDefinitionManager = contentDefinitionManager;
+            Shape = shapeFactory;
+            T = NullLocalizer.Instance;
+        }
+
+        public void Describe(DescribeContext context) {
+            Func<IShapeFactory, object> form =
+                shape => {
+
+                    var f = Shape.Form(
+                        Id: "AnyOfContentParts",
+                        _Parts: Shape.SelectList(
+                            Id: "contentparts", Name: "ContentParts",
+                            Title: T("Content parts"),
+                            Description: T("Select some content parts."),
+                            Size: 10,
+                            Multiple: true
+                            )
+                        );
+
+                    f._Parts.Add(new SelectListItem { Value = "", Text = T("Any").Text });
+
+                    foreach (var contentPart in _contentDefinitionManager.ListPartDefinitions().OrderBy(x => x.Name)) {
+                        f._Parts.Add(new SelectListItem { Value = contentPart.Name, Text = contentPart.Name });
+                    }
+
+                    return f;
+                };
+
+            context.Form("ContentPartsForm", form);
+
+        }
+    }
+}

src/Orchard.Web/Modules/Orchard.Projections/Providers/Filters/EagerFetchFilter.cs

@@ -0,0 +1,42 @@
+using System;
+using Orchard.Localization;
+using Orchard.Projections.Descriptors.Filter;
+using IFilterProvider = Orchard.Projections.Services.IFilterProvider;
+
+namespace Orchard.Projections.Providers.Filters {
+    public class EagerFectchFilter : IFilterProvider {
+        public EagerFectchFilter() {
+            T = NullLocalizer.Instance;
+        }
+
+        public Localizer T { get; set; }
+
+        public void Describe(DescribeFilterContext describe) {
+            describe.For("Content", T("Content"),T("Content"))
+                .Element("EagerFetch", T("Eager fetch"), T("Eager fetch content parts"),
+                    ApplyFilter,
+                    DisplayFilter,
+                    "ContentPartsForm"
+                );
+
+        }
+
+        public void ApplyFilter(FilterContext context) {
+            var contentPartNames = (string)context.State.ContentParts;
+            if (!String.IsNullOrEmpty(contentPartNames)) {
+                var contentParts = contentPartNames.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
+                context.Query = context.Query.Include(contentParts);
+            }
+        }
+
+        public LocalizedString DisplayFilter(FilterContext context) {
+            string contentparts = context.State.ContentParts;
+
+            if (String.IsNullOrEmpty(contentparts)) {
+                return T("No content part");
+            }
+
+            return T("Eager fetch parts {0}", contentparts);
+        }
+    }
+}

src/Orchard/ContentManagement/DefaultHqlQuery.cs

@@ -18,14 +18,14 @@ namespace Orchard.ContentManagement {
         private readonly IEnumerable<ISqlStatementProvider> _sqlStatementProviders;
         private readonly ShellSettings _shellSettings;
         private VersionOptions _versionOptions;
+        private string[] _includedPartNames = new string[0];
+        private bool _cacheable;
 
         protected IJoin _from;
         protected readonly List<Tuple<IAlias, Join>> _joins = new List<Tuple<IAlias, Join>>();
         protected readonly List<Tuple<IAlias, Action<IHqlExpressionFactory>>> _wheres = new List<Tuple<IAlias, Action<IHqlExpressionFactory>>>();
         protected readonly List<Tuple<IAlias, Action<IHqlSortFactory>>> _sortings = new List<Tuple<IAlias, Action<IHqlSortFactory>>>();
 
-        private bool cacheable;
-
         public IContentManager ContentManager { get; private set; }
 
         public DefaultHqlQuery(
@@ -74,13 +74,18 @@ namespace Orchard.ContentManagement {
             return BindCriteriaByAlias(BindItemCriteria(), "ContentType", "ct");
         }
 
-        internal IAlias BindItemCriteria() {
+        internal IAlias BindItemCriteria(string type = "") {
             // [ContentItemVersionRecord] >join> [ContentItemRecord]
-            return BindCriteriaByAlias(BindItemVersionCriteria(), typeof(ContentItemRecord).Name, "ci");
+            return BindCriteriaByAlias(BindItemVersionCriteria(type), typeof(ContentItemRecord).Name, "ci");
         }
 
-        internal IAlias BindItemVersionCriteria() {
-            return _from ?? (_from = new Join(typeof(ContentItemVersionRecord).FullName, "civ", ""));
+        internal IAlias BindItemVersionCriteria(string type = "") {
+            _from = _from ?? new Join(typeof(ContentItemVersionRecord).FullName, "civ", type);
+            if (_from.Type.Length < type.Length) {
+                _from.Type = type;
+            }
+
+            return _from;
         }
 
         internal IAlias BindPartCriteria<TRecord>() where TRecord : ContentPartRecord {
@@ -152,6 +157,12 @@ namespace Orchard.ContentManagement {
             if (contentTypeNames != null && contentTypeNames.Length != 0) {
                 Where(BindTypeCriteria(), x => x.InG("Name", contentTypeNames));
             }
+            
+            return this;
+        }
+
+        public IHqlQuery Include(params string[] partNames) {
+            _includedPartNames = _includedPartNames.Union(partNames).ToArray();
             return this;
         }
 
@@ -170,13 +181,13 @@ namespace Orchard.ContentManagement {
 
         public IEnumerable<ContentItem> Slice(int skip, int count) {
             ApplyHqlVersionOptionsRestrictions(_versionOptions);
-            cacheable = true;
+            _cacheable = true;
             
             var hql = ToHql(false);
 
             var query = _session
                 .CreateQuery(hql)
-                .SetCacheable(cacheable)
+                .SetCacheable(_cacheable)
                 ;
 
             if (skip != 0) {
@@ -191,7 +202,9 @@ namespace Orchard.ContentManagement {
                 .List<IDictionary>()
                 .Select(x => (int)x["Id"]);
 
-            return ContentManager.GetManyByVersionId(ids, QueryHints.Empty);
+            var contentPartRecords = _includedPartNames.Select(part => part + "Record").ToList();
+
+            return ContentManager.GetManyByVersionId(ids, new QueryHints().ExpandRecords(contentPartRecords));
         }
 
         public int Count() {
@@ -224,7 +237,7 @@ namespace Orchard.ContentManagement {
                     }
                     else {
                         // select distinct can't be used with newid()
-                        cacheable = false;
+                        _cacheable = false;
                         sb.Replace("select distinct", "select ");
                     }
                 }

src/Orchard/ContentManagement/IHqlQuery.cs

@@ -18,6 +18,11 @@ namespace Orchard.ContentManagement {
         /// Add content type constraints to the query.
         /// </summary>
         IHqlQuery ForType(params string[] contentTypes);
+
+        /// <summary>
+        /// Eagerly fetches specific content parts.
+        /// </summary>
+        IHqlQuery Include(params string[] contentParts);
         
         /// <summary>
         /// Adds versioning options to the query.