refactor: enable other data meta models

src/cli.ts

@@ -17,6 +17,7 @@ import {
 import { Bye } from "./cli-error.js";
 import { GeoPackageParser } from "./geopackage.js";
 import { EXTENSION_MIMETYPES, mimetypeForExtension } from "./mimetypes.js";
+import { ModelRegistry } from "./models/models.js";
 import { FX, GEO, RDFNS, XSD, XYZ } from "./prefixes.js";
 
 const pipeline = promisify(streampipeline);
@@ -53,7 +54,7 @@ async function cli() {
     .option("model", {
       desc: "Data meta model",
     })
-    .choices("model", ["facade-x"])
+    .choices("model", ModelRegistry.knownModels())
     .parse();
 
   if (!existsSync(argv.input)) Bye(`File '${argv.input}' not found`);
@@ -77,9 +78,11 @@ async function cli() {
     : mimetypeForExtension(path.extname(argv.output)) ??
       mimetypeForExtension("nq");
   const wantsGzip: boolean = argv.output?.endsWith(".gz");
+  const model: string = argv.model ?? ModelRegistry.knownModels()[0];
 
   const parser = new GeoPackageParser(argv.input, {
-    boundingBox: boundingBox,
+    model,
+    boundingBox,
     allowedLayers: argv.onlyLayers,
     baseIRI: argv.baseIri ?? pathToFileURL(argv.input).href,
     includeBinaryValues: argv.includeBinaryValues,

src/geopackage.ts

@@ -2,7 +2,14 @@ import { BoundingBox, GeoPackage, GeoPackageAPI } from "@ngageoint/geopackage";
 import type * as RDF from "@rdfjs/types";
 import { Readable } from "node:stream";
 import { DataFactory } from "rdf-data-factory";
-import { quadsFromGeoPackage } from "./rdf-geopackage.js";
+import { quadsFromGeoPackage } from "./models/facade-x/rdf-geopackage.js";
+import { ModelRegistry, QuadsGeneratorFunc } from "./models/models.js";
+
+// Register known quad generating modules here.
+// I don't know how to make this a true plugin (but that's not really necessary either)
+const WellKnownModels = { "facade-x": quadsFromGeoPackage };
+for (const [modelName, func] of Object.entries(WellKnownModels))
+  ModelRegistry.add(modelName, func);
 
 export interface GeoPackageOptions {
   /** Pass a data factory or rdf-data-factory is used */
@@ -16,6 +23,8 @@ export interface GeoPackageOptions {
   boundingBox?: BoundingBox;
   /** Generate quads where the object/value is a binary (Base-64 encoded). */
   includeBinaryValues?: boolean;
+  /** Data meta model by which triples are generated */
+  model: string;
 }
 
 export class GeoPackageParser extends Readable implements RDF.Stream {
@@ -24,6 +33,7 @@ export class GeoPackageParser extends Readable implements RDF.Stream {
   iterQuad: Generator<RDF.Quad>;
   gpkg: GeoPackage;
   shouldRead: boolean;
+  generator: QuadsGeneratorFunc;
 
   /**
    * Read a GeoPackage and output a stream of RDF.Quads
@@ -35,14 +45,15 @@ export class GeoPackageParser extends Readable implements RDF.Stream {
 
     this.filepath = filepath;
     this.options = { dataFactory: new DataFactory(), ...options };
+    this.generator = ModelRegistry.get(this.options.model);
     this.shouldRead = false;
   }
 
   _construct(callback: (error?: Error) => void): void {
     GeoPackageAPI.open(this.filepath)
       .then((gpkg) => {
         this.gpkg = gpkg;
-        this.iterQuad = quadsFromGeoPackage(this.gpkg, this.options);
+        this.iterQuad = this.generator(this.gpkg, this.options);
         callback();
       })
       .catch(callback);

src/rdf-attribute-table.ts → src/models/facade-x/rdf-attribute-table.ts

@@ -1,5 +1,5 @@
 import type { DBValue } from "@ngageoint/geopackage/dist/lib/db/dbAdapter.js";
-import { enumerate } from "./py-enumerate.js";
+import { enumerate } from "../../py-enumerate.js";
 import {
   QuadsFromTableOptions,
   getRowNode,

src/rdf-feature-table.ts → src/models/facade-x/rdf-feature-table.ts

@@ -4,8 +4,8 @@ import type * as RDF from "@rdfjs/types";
 import type { Feature, Geometry } from "geojson";
 import stringify from "json-stable-stringify";
 import { DataFactory } from "rdf-data-factory";
-import { GEO, RDFNS } from "./prefixes.js";
-import { enumerate } from "./py-enumerate.js";
+import { GEO, RDFNS } from "../../prefixes.js";
+import { enumerate } from "../../py-enumerate.js";
 import {
   QuadsFromTableOptions,
   getRowNode,

src/rdf-geopackage.ts → src/models/facade-x/rdf-geopackage.ts

@@ -1,6 +1,6 @@
 import { GeoPackage } from "@ngageoint/geopackage";
 import type * as RDF from "@rdfjs/types";
-import { GeoPackageOptions } from "./geopackage.js";
+import { GeoPackageOptions } from "../../geopackage.js";
 import { quadsFromAttributeTable } from "./rdf-attribute-table.js";
 import { quadsFromFeatureTable } from "./rdf-feature-table.js";
 

src/rdf-table-common.ts → src/models/facade-x/rdf-table-common.ts

@@ -2,7 +2,7 @@ import type { DBValue } from "@ngageoint/geopackage/dist/lib/db/dbAdapter.js";
 import type * as RDF from "@rdfjs/types";
 import { DataFactory } from "rdf-data-factory";
 import { toRdf } from "rdf-literal";
-import { FX, RDFNS, XSD, XYZ } from "./prefixes.js";
+import { FX, RDFNS, XSD, XYZ } from "../../prefixes.js";
 
 export interface QuadsFromTableOptions {
   /** Name of the originating table */

src/models/models.ts

@@ -0,0 +1,42 @@
+import type { GeoPackage } from "@ngageoint/geopackage";
+import type * as RDF from "@rdfjs/types";
+import type { GeoPackageOptions } from "../geopackage.js";
+
+/**
+ * The type signature of a quads generating function
+ *
+ * @param geopackage The GeoPackage instance
+ * @param options Options that may guide the generation of the quads.
+ */
+export type QuadsGeneratorFunc = (
+  geopackage: GeoPackage,
+  options: GeoPackageOptions,
+) => Generator<RDF.Quad>;
+
+/** Singleton registry of Quad generating models */
+export class ModelRegistry {
+  private static MODEL_REGISTRY: Record<string, QuadsGeneratorFunc> = {};
+  /**
+   * Register a quads generator
+   *
+   * @param modelName Name to register the model by
+   * @param mainFunc Function that returns a quads generator
+   */
+  static add(modelName: string, mainFunc: QuadsGeneratorFunc) {
+    this.MODEL_REGISTRY[modelName] = mainFunc;
+  }
+
+  /**
+   * Get a registered quads generator
+   *
+   * @param modelName Name of registered generator
+   */
+  static get(modelName: string): QuadsGeneratorFunc {
+    return this.MODEL_REGISTRY[modelName];
+  }
+
+  /** Return a list of known models */
+  static knownModels(): string[] {
+    return Object.keys(this.MODEL_REGISTRY);
+  }
+}