Table of Contents

EncDotNet.S100.Datasets.S127

Library for reading and portraying IHO S-127 (Marine Resources and Services) datasets.

S-127 provides a standard data model for distributing marine traffic-management information — pilot boarding places, routeing measures, restricted areas, vessel traffic services, signal stations, and similar features — as GML-encoded datasets conforming to the S-100 framework.

Features

  • Parse S-127 GML datasets (S-100 Part 10b encoding)
  • Tolerates both the current S-100 GML 5.0 namespace (http://www.iho.int/s100gml/5.0) and the legacy 1.0 namespace
  • Convert to S-100 Part 9 FeatureXML for portrayal pipeline consumption
  • XSLT-based portrayal via the bundled S-127 Portrayal Catalogue (Edition 2.0.0)

Overview

Key types:

  • S127Dataset — root model containing parsed features, information types, and dataset identification. ReadMetadata() (plus static ReadMetadata(path) / ReadMetadata(stream)) is the phased-loading "peek" path (issue #460): it returns a DatasetMetadata with the declared spec and the raw WGS-84 extent folded from feature geometry (null when the dataset carries only geometry-less container features), skipping the XSLT portrayal pipeline.
  • S127Feature — a geographic feature with type code, geometry, simple attributes, and complex attributes.
  • S127InformationType — a non-geographic information type instance (S-127 Edition 2.0.0 declares none, but the parser preserves any imember content for forward compatibility).
  • S127ComplexAttribute — a complex attribute instance containing sub-attribute values.
  • S100GeometryType — enum describing the geometry primitive type of a feature.
  • FeatureXML projection — there is no S-127-specific source type: the S-127 dataset processor in EncDotNet.S100.Datasets.Pipelines projects an S127Dataset into S-100 Part 9 FeatureXML (Dataset/Features/*) for the bundled main.xsl rule with the shared GmlFeatureXmlSource<TFeature> from EncDotNet.S100.Core.
  • Feature geometry reaches the renderers through the shared FeatureGeometryProvider<TFeature> (IFeatureGeometryProvider, from EncDotNet.S100.Core), which the dataset processor builds over the parsed features.
  • S127PortrayalCatalogue — IVectorPortrayalCatalogue implementation that loads XSLT rules, SVG symbols, line styles, and color palettes.

Quick start

using EncDotNet.S100.Datasets.S127;
using EncDotNet.S100.Pipelines;
using EncDotNet.S100.Portrayals;
using EncDotNet.S100.Specifications;

var dataset = S127Dataset.Open("pilot_boarding.gml");

var manager = new PortrayalCatalogueManager(productSpec =>
    Specification.CreatePortrayalCatalogueSource(productSpec));
var catalogue = new S127PortrayalCatalogue(manager.GetProvider("S-127"));
catalogue.SwitchPalette(PaletteType.Day);

var source = new S127FeatureXmlSource(dataset);
var instructions = await new PortrayalPipeline().ProcessAsync(source, catalogue);

Strongly-typed data model

Alongside the GML-faithful S127Dataset feature bag, the library exposes a strongly-typed projection rooted at S127MarineServicesDataset (namespace EncDotNet.S100.Datasets.S127.DataModel). It mirrors the typed projections in S-124, S-125, S-128, and S-201.

using EncDotNet.S100.Datasets.S127;
using EncDotNet.S100.Datasets.S127.DataModel;

var dataset = S127Dataset.Open("marine_services.gml");
var typed = S127MarineServicesDataset.From(dataset, out var diagnostics);

foreach (var pbp in typed.Features.OfType<S127PilotBoardingPlace>())
{
    Console.WriteLine($"{pbp.Id}: {pbp.CategoryOfPilotBoardingPlace} / {pbp.Authority?.Id}");
}

The projection:

  • Models the headline S-127 feature classes — S127PilotBoardingPlace, S127RouteingMeasure, S127VesselTrafficServiceArea, S127ShipReportingService, S127SignalStation (Traffic / Warning discriminator), S127RegulatedArea (covers RestrictedArea, RestrictedAreaNavigational, MilitaryPracticeArea, CautionArea, etc.), and S127Authority. Every other FC code falls through to a S127OtherFeature catch-all so no source geometry or attribute is lost.
  • Surfaces feature-to-feature xlink:href bindings (e.g. theAuthority) as typed IS127Feature references. Resolution is two-pass: every typed object is built first, then bound, so cycle-tolerant references work.
  • Handles geometry-less features (e.g. Authority) without throwing — GeometryKind is None and Coordinates is empty.
  • Reports unresolved xlinks and attribute parse failures as ProjectionDiagnostic entries (codes xlink.unresolved, attribute.parse.int); it only throws when the source dataset is fully empty.
  • Preserves source attributes verbatim on every typed shape via ExtraAttributes (consumed keys are excluded).

The viewer, FeatureXML adapter, and XSLT portrayal pipeline continue to drive off S127Dataset and are unaffected by this layer.

Validation

EncDotNet.S100.Datasets.S127.Validation.S127MarineServicesRules exposes a pilot rule set of Tier-1 / Tier-2 validation rules that operate on S127MarineServicesDataset. Rule identifiers follow the S127-R-{clause} convention and trace back to S-127 Edition 2.0.0 § references.

using EncDotNet.S100.Datasets.S127;
using EncDotNet.S100.Datasets.S127.DataModel;
using EncDotNet.S100.Datasets.S127.Validation;

var dataset = S127Dataset.Open("marine_services.gml");
var typed = S127MarineServicesDataset.From(dataset, out _);
var report = S127MarineServicesRules.Validate(typed);

foreach (var finding in report.Findings)
    Console.WriteLine($"{finding.RuleId} [{finding.Severity}] {finding.Message}");

Default rules:

Rule ID Summary Severity
S127-R-12.1 Coordinates must lie within WGS-84 lat/lon ranges (S-100 Part 10b §6.2). Error
S127-R-12.2 PilotBoardingPlace features must carry a non-empty geometry. Error
S127-R-12.3 Surface exterior rings must have ≥4 vertices and be closed. Error
S127-R-12.4 Curve geometries must have ≥2 vertices. Error
S127-R-12.5 Vessel-size limit minimums (length / draught / beam) must not exceed their maximums. Warning
S127-R-12.6 Availability time-of-day / date ranges must have start ≤ end. Warning
S127-R-12.7 Feature identifiers must be unique within the dataset. Error
S127-R-12.8 Authority features should carry a non-empty authorityName. Warning

Container-style features (e.g. Authority) without geometry are tolerated — they trivially pass geometry-shape rules. Two candidate rules — VTS report-point geometry (deferred pending cross-feature xlink resolution) and closed-enumeration validity for categoryOfService (deferred pending typed enum surfaces) — are intentionally not included; see the class-level remarks in S127MarineServicesRules for the reasoning.

Spec compliance

  • Coordinate ordering in <gml:pos> / <gml:posList> is lat lon (EPSG:4326), per S-100 Part 10b §6.2.
  • The reader treats every <member> child whose namespace matches the dataset's application schema as a feature wrapper, so additions to the S-127 Feature Catalogue do not require parser changes.
  • Bundled portrayal assets are byte-identical to upstream iho-ohi/S-127-Product-Specification-Development (PC 2.0.0).

Installation

dotnet add package EncDotNet.S100.Datasets.S127
Edit this page