README.md

ASP.NET Core WebAPI? You should start with Panner.AspNetCore!

Panner

Clean, customizable & extensible framework for the configuration, parsing and application of sorts and filters from a CSV.

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Basic Usage - Sample

a. Configuration

Setting up your context to define your entities and rules.

var builder = new PContext();

// Entity wide configuration (Option 1)
builder.Entity<Post>()
    .AllPropertiesAreSortableByName();
    .AllPropertiesAreFilterableByName();

// A more granular approach (Option 2)
builder.Entity<Post>()
    .Property(x => x.Id, o => o
        .IsSortableByName()
        .IsFilterableByName()
    ).Property(x => x.Title, o => o
        .IsSortableByName()
        .IsFilterableByName()
    ).Property(x => x.CreatedOn, o => o
        .IsSortableAs("Creation")
        .IsFilterableAs("Creation")
    );

// And then we build our context.
IPContext context = builder.Build(); 

// Ta-daah! Now we have a context!

b. Parsing

Feeding Panner's context our CSV inputs and obtaining sort/filter particles

Sorts

var csvSort = "-Title, Id"; // Example

if (!context.TryParseCsv(
    input: csvSort,
    out IEnumerable<ISortParticle<TEntity>> sortParticles
)){
    // Parsing failed
    return;
}

// Ta-daah! Now we have sort particles!

Filters

var csvFilter = "Id<666, Id>13"; // Example

if (!context.TryParseCsv(
    input: csvFilter,
    out IEnumerable<IFilterParticle<TEntity>> filterParticles
)){
    // Parsing failed
    return;
}

// Ta-daah! Now we have filter particles!

c. Application

Using Panner's extension methods to apply our particles to any IEnumerable, IQueryable, DbSet, etc..

var pannedQueryable = posts
    .Apply(filterParticles)
    .Apply(sortParticles);

// Ta-daah! Now we have a filtered and sorted IQueryable!

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Advanced Usage - Samples

Custom sort for a specific entity
Ability to sort our fake entity Post by "popularity", an arbritary concept and not a property of the entity.
Leveraging ISortParticle, ISortParticleGenerator and extending PEntityBuilder.

Particle - SortPostByPopularityParticle.cs

public class SortPostByPopularityParticle : ISortParticle<Post> // Panner's interface
{
    readonly bool Descending;

    public SortPostByPopularityParticle(bool descending)
    {
        this.Descending = descending;
    }

    public IOrderedQueryable<Post> ApplyTo(IOrderedQueryable<Post> source)
    {
        // Here's how the sorting is done when the particle is applied.
        if (this.Descending)
            return source
                .ThenByDescending(x => x.AmtLikes)
                .ThenByDescending(x => x.AmtComments);
        else
            return source
                .ThenBy(x => x.AmtLikes)
                .ThenBy(x => x.AmtComments);
    }
}

Particle Generator - SortPostsByPopularityParticleGenerator.cs

public class SortPostsByPopularityParticleGenerator : ISortParticleGenerator<Post> // Panner's interface
{
    public bool TryGenerate(IPContext context, string input, out ISortParticle<Post> particle)
    {
        var descending = input.StartsWith('-');
        var remaining = descending ? input.Substring(1) : input;

        if (!remaining.Trim().Equals("Popularity", System.StringComparison.OrdinalIgnoreCase))
        {
            // Not the input we're interested in.
            particle = null;
            return false;
        }

        particle = new SortPostByPopularityParticle(descending);
        return true;
    }
}

PEntityBuilder Extension - PEntityBuilder.Post.IsSortableByPopularity.cs

public static partial class PEntityBuilderExtensions
{
    /// <summary>Marks the entity as sortable by popularity.</summary>
    public static PEntityBuilder<Post> IsSortableByPopularity(this PEntityBuilder<Post> builder)
    {
        builder.GetOrCreateGenerator<ISortParticle<Post>, SortPostsByPopularityParticleGenerator>();
        return builder; // So we can chain calls!
    }
}

Setting it all up in the context builder

builder.Entity<Post>()
    .IsSortableByPopularity();

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Frequently Asked Questions

Using different culture for filter value conversions?

You can change CurrentInfo.CurrentCulture before calling context.TryParseCsv([...])!

CurrentInfo.CultureInfo = new CultureInfo("es"); //So simple...!