generating stable feature id

web/app/cad/craft/operationBundle.ts

@@ -99,7 +99,7 @@ export function activate(ctx: ApplicationContext) {
     ctx.actionService.registerActions(actions);
   }
 
-  function get<T>(id: string): Operation<T> {
+  function get<T extends FeatureIdParam>(id: string): Operation<T> {
     const op = registry$.value[id];
     if (!op) {
       throw `operation ${id} is not registered`;
@@ -115,7 +115,11 @@ export function activate(ctx: ApplicationContext) {
   ctx.services.operation = ctx.operationService;
 }
 
-export interface Operation<R> extends OperationDescriptor<R>{
+interface FeatureIdParam {
+  featureId: string;
+}
+
+export interface Operation<R extends FeatureIdParam> extends OperationDescriptor<R>{
   appearance: {
     id: string;
     label: string;
@@ -133,7 +137,7 @@ type OpIcon = IconDeclaration | IconType | string | ((props: any) => JSX.Element
 
 type MaterializedParams = any;
 
-export interface OperationDescriptor<R> {
+export interface OperationDescriptor<R extends FeatureIdParam> {
   id: string;
   label: string;
   info: string;
@@ -162,7 +166,7 @@ export interface OperationDescriptor<R> {
 
 export interface OperationService {
   registerOperations(descriptior: OperationDescriptor<any>[]);
-  get<T>(operationId: string): Operation<T>;
+  get<T extends FeatureIdParam>(operationId: string): Operation<T>;
 }
 
 export type Index<T> = {

web/app/cad/craft/schema/initializeBySchema.ts

@@ -4,7 +4,9 @@ import {ApplicationContext} from "cad/context";
 
 export default function initializeBySchema(schema: OperationSchema, context: ApplicationContext) {
   const fields = Object.keys(schema);
-  const obj = {};
+  const obj = {
+    featureId: context.projectService.counterGenerator.generateFeatureId()
+  };
   for (const field of fields) {
     let val = undefined;
     const md = schema[field] as SchemaField;

web/app/cad/craft/ui/HistoryTimeline.jsx

@@ -139,7 +139,7 @@ function HistoryItem({index, pointer, modification, getOperation, toggle, select
   return <div className={cx(ls.historyItem, selected&&ls.selected, disabled&&ls.disabled, inProgress&&ls.inProgress)}
               onClick={e => toggle(index, modification, e.currentTarget)}>
     <ImgIcon className={ls.opIcon} url={appearance&&appearance.icon96} size={24} />
-    <span className={ls.opIndex}>{ index + 1 }</span>
+    <span className={ls.opIndex}>{ modification.params.featureId }</span>
   </div>;
 });
 

web/app/cad/craft/ui/SelectedModificationInfo.jsx

@@ -43,12 +43,11 @@ function SelectedModificationInfo({ history, index,
   }
   const appearance = resolveAppearance(op, m.params);
 
-  const indexNumber = index + 1;
   return <Widget visible={visible}
                  left={lh && lh.x}
                  bottom={95}
                  flatRight={!lh}
-                 title={appearance.label.toUpperCase() + ' operation #' + indexNumber}
+                 title={appearance.label.toUpperCase() + ' operation #' + m.params.featureId}
                  onClose={close}>
     <div className={ls.requestInfo}>
       <ImgIcon className={ls.pic} url={appearance && appearance.icon96} size={48}/>

web/app/cad/projectBundle.ts

@@ -2,7 +2,7 @@ import {setSketchPrecision} from './sketch/sketchReader';
 import {runSandbox} from './sandbox';
 import {LOG_FLAGS} from './logFlags';
 import {ApplicationContext} from "cad/context";
-import {ProjectModel} from "./projectManager/projectManagerBundle";
+import {ProjectCounters, ProjectModel} from "./projectManager/projectManagerBundle";
 import {DebugMode$} from "debugger/Debugger";
 import {fillUpMissingFields} from "cad/craft/schema/initializeBySchema";
 
@@ -51,6 +51,7 @@ export function initProjectService(ctx: ApplicationContext, id: string, hints: a
     if (!currentWorkbench?.internal && ctx.workbenchService.defaultWorkbenchId !== currentWorkbench.workbenchId) {
       data.workbench = currentWorkbench.workbenchId;
     }
+    data.counters = counterGenerator.projectCounters;
     ctx.storageService.set(projectStorageKey(), JSON.stringify(data));
   }
 
@@ -74,9 +75,15 @@ export function initProjectService(ctx: ApplicationContext, id: string, hints: a
         const operation = ctx.operationService.get(req.type);
         if (operation) {
           fillUpMissingFields(req.params, operation.schema, ctx);
+          if (!req.params.featureId) {
+            req.params.featureId = counterGenerator.generateFeatureId();
+          }
         }
       });
     }
+    if (!data.counters) {
+      data.counters = new ProjectCounters();
+    }
   }
 
   function loadWorkbench(data: ProjectModel) {
@@ -99,6 +106,7 @@ export function initProjectService(ctx: ApplicationContext, id: string, hints: a
       ctx.assemblyService.loadConstraints(data.assembly);
     }
 
+    counterGenerator = new ProjectCounterGenerator(data.counters);
   }
 
   function empty() {
@@ -108,9 +116,11 @@ export function initProjectService(ctx: ApplicationContext, id: string, hints: a
     });
   }
 
+  let counterGenerator = new ProjectCounterGenerator(new ProjectCounters());
+
   ctx.projectService = {
     id, sketchStorageKey, projectStorageKey, sketchStorageNamespace, getSketchURL, save, load, loadData, empty,
-    hints
+    hints, counterGenerator
   };
 
 }
@@ -161,6 +171,19 @@ function processParams(params, context) {
   }
 }
 
+export class ProjectCounterGenerator {
+
+  projectCounters: ProjectCounters;
+
+  constructor(projectCounters) {
+    this.projectCounters = projectCounters;
+  }
+
+  generateFeatureId(): string {
+    return (++this.projectCounters.featureId) + "";
+  }
+}
+
 export interface ProjectService {
 
   readonly id: string;
@@ -183,6 +206,7 @@ export interface ProjectService {
 
   empty(): void;
 
+  counterGenerator: ProjectCounterGenerator;
 }
 
 export interface ProjectBundleContext {

web/app/cad/projectManager/projectManagerBundle.ts

@@ -197,6 +197,10 @@ export function activate(ctx: ApplicationContext) {
   ctx.services.projectManager = ctx.projectManager;
 }
 
+export class ProjectCounters {
+  featureId: number = 0;
+}
+
 export interface ProjectModel {
 
   history: OperationRequest[],
@@ -205,7 +209,9 @@ export interface ProjectModel {
 
   assembly?: AssemblyConstraintDefinition[];
 
-  workbench?: string
+  workbench?: string,
+
+  counters?: ProjectCounters;
 }
 
 export interface ModelBundle {