sbkst.Cofoundry.CustomEntitySearch 0.1.0

Cofoundry.CustomEntitySearch

Search Custom Entities out-of-box with SQL Server´s JSON_VALUE function. The API was designed to fit the common cofoundry structure.

Info

This package extends cofoundry (https://www.cofoundry.org) with the capabilities to query custom entities using the SQL Server JSON_VALUE function. I am in no way affiliate with cofoundry.

Why

I know there are (probably) more viable solutions to this problem (see https://github.com/cofoundry-cms/cofoundry/issues/31) but I needed this as out-of-the-box functionality really quickly.

Installation

Just reference the package in your cofoundry project.

How to use

Using the cofoundry Sample Site as example (https://github.com/cofoundry-cms/Cofoundry.Samples.SimpleSite)

To implement the category search thats currently missing in BlogPostListViewComponent (https://github.com/cofoundry-cms/Cofoundry.Samples.SimpleSite/blob/master/src/Cofoundry.Samples.SimpleSite/ViewComponents/BlogPostListViewComponent.cs) we first implement a specification to search

    public class BlogPostCategorySpecification : CustomEntitySearchSpecificationBase<BlogPostDataModel>
    {
        private readonly int _categoryId;
        public BlogPostCategorySpecification(int categoryId)
        {
            _categoryId = categoryId;
        }

        public override Expression<Func<BlogPostDataModel, bool>> SatisfiedBy => c => c.CategoryId == _categoryId;
    }
	

The CustomEntitySearchSpecificationBase class inherits the SatisfiedBy predicate to our specification which is later on used to query the custom entity.

Now we exchange the ICustomEntityRepository dependency in BlogPostListViewComponent to ISearchableCustomEntityRepository

        private readonly ISearchableCustomEntityRepository _customEntityRepository;
        private readonly IImageAssetRepository _imageAssetRepository;
        private readonly IVisualEditorStateService _visualEditorStateService;

        public BlogPostListViewComponent(
            ICustomEntityRepository customEntityRepository,
            IImageAssetRepository imageAssetRepository,
            IVisualEditorStateService visualEditorStateService
            )
        {
            _customEntityRepository = customEntityRepository;
            _imageAssetRepository = imageAssetRepository;
            _visualEditorStateService = visualEditorStateService;
        }

finally we can query like this, in this example we query all custom entites with category id 1

        public async Task<IViewComponentResult> InvokeAsync()
        {
            var webQuery = new SearchBlogPostsQuery();
            var query = new SearchCustomEntitiesQuery();
            query.CustomEntityDefinitionCode = BlogPostCustomEntityDefinition.DefinitionCode;
            query.PageNumber = webQuery.PageNumber;
            query.PageSize = 30;

            var specifications = new List<ICustomEntitySearchSpecification<BlogPostDataModel>>();
            specifications.Add(new BlogPostCategorySpecification(1));
            query.Specifications = specifications;
            var state = await _visualEditorStateService.GetCurrentAsync();
            query.PublishStatus = state.GetAmbientEntityPublishStatusQuery();
            var entities = await _customEntityRepository.SearchCustomEntityRenderSummariesAsync(query);
            var viewModel = await MapBlogPostsAsync(entities);

            return View(viewModel);
        }

As this functionality is based on the ef core linq / remotion implementation any predicate that is understood by ef core can be used to query

e.G.

    public class BlogPostShortDescriptionContainsSpecification : CustomEntitySearchSpecificationBase<BlogPostDataModel>
    {
        private readonly string _contains;
        public BlogPostShortDescriptionContainsSpecification(string contains)
        {
            _contains = contains;
        }

        public override Expression<Func<BlogPostDataModel, bool>> SatisfiedBy => c => c.ShortDescription.Contains(_contains);
    }

Multiple specifications can be passed to the query, as they are passed in they all get linked logically with AND.

e.G.

            var specifications = new List<ICustomEntitySearchSpecification<BlogPostDataModel>>();
            specifications.Add(new BlogPostCategorySpecification(1));
            specifications.Add(new BlogPostShortDescriptionContainsSpecification("test"));
            query.Specifications = specifications;

For more complex queries or OR queries simply implement a own specification and define those in the SatisfiedBy predicate.

Technichal FAQ

F: Why rewrite the Expression twice?

A: One is the transformation of the Specifications into the expression and the second time it gets rewritten to use JSON_VALUE. This design choice was made so one could write a different mapping for Specifications (for exmaple mapping directly to a SQL String or Elastic Search query) while the query itself can still remain this way or be entirely replaced.