feat(core): allow to export / import classifications

packages/core/package.json

@@ -1,7 +1,7 @@
 {
   "name": "@thatopen/components",
   "description": "Collection of core functionalities to author BIM apps.",
-  "version": "2.4.0-alpha.6",
+  "version": "2.4.0-alpha.7",
   "author": "That Open Company",
   "contributors": [
     "Antonio Gonzalez Viegas (https://github.com/agviegas)",

packages/core/src/fragments/Classifier/index.ts

@@ -35,6 +35,16 @@ export interface Classification {
   };
 }
 
+interface ExportedClassification {
+  [system: string]: {
+    [groupName: string]: {
+      map: string;
+      name: string;
+      id: number | null;
+    };
+  };
+}
+
 /**
  * The Classifier component is responsible for classifying and categorizing fragments based on various criteria. It provides methods to add, remove, find, and filter fragments based on their classification. 📕 [Tutorial](https://docs.thatopen.com/Tutorials/Components/Core/Classifier). 📘 [API](https://docs.thatopen.com/api/@thatopen/components/classes/Classifier).
  */
@@ -494,6 +504,52 @@ export class Classifier extends Component implements Disposable {
     }
   }
 
+  /**
+   * Exports the computed classification to persists them and import them back
+   * later for faster loading.
+   */
+  export() {
+    const exported: ExportedClassification = {};
+
+    for (const systemName in this.list) {
+      exported[systemName] = {};
+      const system = this.list[systemName];
+      for (const groupName in system) {
+        const group = system[groupName];
+        exported[systemName][groupName] = {
+          map: FRAGS.FragmentUtils.export(group.map),
+          name: group.name,
+          id: group.id,
+        };
+      }
+    }
+
+    return JSON.stringify(exported);
+  }
+
+  /**
+   * Imports a classification previously exported with .export().
+   * @param data the serialized classification to import.
+   */
+  import(data: string) {
+    const imported = JSON.parse(data) as ExportedClassification;
+
+    for (const systemName in imported) {
+      if (!this.list[systemName]) {
+        this.list[systemName] = {};
+      }
+      const system = imported[systemName];
+      for (const groupName in system) {
+        const group = system[groupName];
+        this.list[systemName][groupName] = {
+          map: FRAGS.FragmentUtils.import(group.map),
+          name: group.name,
+          id: group.id,
+        };
+      }
+    }
+  }
+
   protected saveItem(
     group: FRAGS.FragmentsGroup,
     systemName: string,