Indicator catalog development

File

src/{category}/{Indicator}/{Indicator}.Catalog.cs

Builder pattern

public static partial class Ema
{
    /// <summary>
    /// EMA Common Base Listing
    /// </summary>
    internal static readonly IndicatorListing CommonListing =
        new CatalogListingBuilder()
            .WithName("Exponential Moving Average")
            .WithId("EMA")
            .WithCategory(Category.MovingAverage)
            .AddParameter<int>("lookbackPeriods", "Lookback Period",
                description: "Number of periods for the EMA calculation",
                isRequired: true, defaultValue: 20, minimum: 2, maximum: 250)
            .AddResult("Ema", "EMA", ResultType.Default, isReusable: true)
            .Build();

    /// <summary>
    /// EMA Series Listing
    /// </summary>
    internal static readonly IndicatorListing SeriesListing =
        new CatalogListingBuilder(CommonListing)
            .WithStyle(Style.Series)
            .WithMethodName("ToEma")
            .Build();

    /// <summary>
    /// EMA Stream Listing
    /// </summary>
    internal static readonly IndicatorListing StreamListing =
        new CatalogListingBuilder(CommonListing)
            .WithStyle(Style.Stream)
            .WithMethodName("ToEmaHub")
            .Build();

    /// <summary>
    /// EMA Buffer Listing
    /// </summary>
    internal static readonly IndicatorListing BufferListing =
        new CatalogListingBuilder(CommonListing)
            .WithStyle(Style.Buffer)
            .WithMethodName("ToEmaList")
            .Build();
}

Method naming

Style	Pattern	Example
Series	To{Name}	ToEma
Stream	To{Name}Hub	ToEmaHub
Buffer	To{Name}List	ToEmaList

.WithMethodName() must be in style-specific listings, NOT in CommonListing.

Parameter patterns

• AddParameter<T>() — int, double, bool
• AddEnumParameter<T>() — enum types
• AddDateParameter() — DateTime
• AddSeriesParameter() — IReadOnlyList<T> where T : IReusable
• minimum and maximum required for all numeric parameters

Result patterns

• dataName must match property name in Models file exactly
• isReusable: true only for the property mapping to IReusable.Value
• ISeries models: all results must have isReusable: false
• Exactly one isReusable: true per IReusable indicator

Categories

Category	Examples
CandlestickPattern	Doji, Marubozu
MovingAverage	EMA, SMA, HMA, TEMA, WMA, DEMA
Oscillator	RSI, Stochastic, MACD, CCI, BOP, CMO, Chop, DPO
PriceChannel	Bollinger Bands, Keltner, Donchian, VWAP
PriceCharacteristic	ATR, Beta, Standard Deviation, True Range
PricePattern	Fractal, Pivot Points
PriceTransform	Quote Part, ZigZag
PriceTrend	ADX, Aroon, Alligator, AtrStop, SuperTrend, Vortex
StopAndReverse	Chandelier, Parabolic SAR, Volatility Stop
VolumeBased	OBV, Chaikin Money Flow, Chaikin Oscillator

Registration

src/_common/Catalog/Catalog.Listings.cs, PopulateCatalog() — alphabetical order:

_catalog.Add(Ema.SeriesListing);
_catalog.Add(Ema.StreamListing);
_catalog.Add(Ema.BufferListing);

Prohibited

• .WithMethodName() in CommonListing
• Wrong indicator method name
• isReusable: true for ISeries models
• Multiple isReusable: true results per indicator

Testing

tests/indicators/{folder}/{Indicator}/{Indicator}.Catalog.Tests.cs:

[TestClass]
public class EmaCatalogTests : TestBase
{
    [TestMethod]
    public void EmaSeriesListing()
    {
        var listing = Ema.SeriesListing;
        listing.Name.Should().Be("Exponential Moving Average");
        listing.Style.Should().Be(Style.Series);
        listing.MethodName.Should().Be("ToEma");
    }
}