feat(analytics): ADR-0037 P3 — draft data preview (seed-overlay dataset queries)

packages/rest/src/rest-server.ts

@@ -3648,12 +3648,18 @@ export class RestServer {
                         });
                     }
 
+                    // ADR-0037 P3 — draft data preview: the canvas / preview
+                    // pages pass the flag so (a) the dataset lookup sees
+                    // draft-overlaid definitions and (b) the selection runs
+                    // over the pending seed draft's rows when one exists.
+                    const previewDrafts = body.previewDrafts === true || req.query?.preview === 'draft';
+
                     // Resolve the dataset definition: inline draft (Studio
                     // preview) or a saved dataset by name.
                     let dataset = body.dataset;
                     if (!dataset && body.datasetName) {
                         const p = await this.resolveProtocol(environmentId, req);
-                        const items = await (p as any).getMetaItems?.({ type: 'dataset' }).catch(() => null);
+                        const items = await (p as any).getMetaItems?.({ type: 'dataset', previewDrafts }).catch(() => null);
                         const list = Array.isArray(items?.items) ? items.items : (Array.isArray(items) ? items : []);
                         dataset = list.find((d: any) => d?.name === body.datasetName);
                         if (!dataset) {
@@ -3677,7 +3683,12 @@ export class RestServer {
                         });
                     }
 
-                    const result = await svc.queryDataset(dataset, selection, context ?? undefined);
+                    const result = await svc.queryDataset(
+                        dataset,
+                        selection,
+                        context ?? undefined,
+                        previewDrafts ? { previewDrafts: true } : undefined,
+                    );
                     res.json(result);
                 } catch (error: any) {
                     const msg = String(error?.message ?? error ?? '');

packages/services/service-analytics/src/__tests__/preview-evaluator.test.ts

@@ -0,0 +1,153 @@
+// Copyright (c) 2025 ObjectStack. Licensed under the Apache-2.0 license.
+//
+// ADR-0037 P3 — draft data preview: the evaluator computes a dataset
+// selection over pending seed-draft rows in memory, and queryDataset routes
+// through it (bypassing the engine entirely) when previewDrafts is set and a
+// pending seed exists.
+
+import { describe, it, expect, vi } from 'vitest';
+import { DatasetSchema } from '@objectstack/spec/ui';
+import { AnalyticsService } from '../analytics-service.js';
+import { evaluateAnalyticsQueryOverRows, bucketDate, matchesWhere } from '../preview-evaluator.js';
+import type { Cube } from '@objectstack/spec/data';
+
+const SEED_ROWS = [
+  { title: 'Flight', amount: 1200, category: 'travel', spent_on: '2026-05-03' },
+  { title: 'Hotel', amount: 800, category: 'travel', spent_on: '2026-05-12' },
+  { title: 'Lunch', amount: 60, category: 'meals', spent_on: '2026-06-01' },
+  { title: 'Dinner', amount: 140, category: 'meals', spent_on: '2026-06-02' },
+];
+
+const DATASET = DatasetSchema.parse({
+  name: 'expense_ds',
+  label: 'Expense',
+  object: 'expense',
+  dimensions: [
+    { name: 'category', field: 'category', type: 'string' },
+    { name: 'spent_on', field: 'spent_on', type: 'date', dateGranularity: 'month' },
+  ],
+  measures: [
+    { name: 'count', aggregate: 'count' },
+    { name: 'total_amount', aggregate: 'sum', field: 'amount' },
+  ],
+});
+
+function previewService(rows: Record<string, unknown>[] | null) {
+  // No strategies, no fallback: if the engine path is ever reached the call
+  // throws — which is exactly how we prove preview bypasses it.
+  return new AnalyticsService({
+    draftRowsResolver: vi.fn(async () => rows),
+  });
+}
+
+describe('queryDataset({ previewDrafts }) — seed-overlay preview', () => {
+  it('charts the drafted seed rows without touching the engine', async () => {
+    const result = await previewService(SEED_ROWS).queryDataset(
+      DATASET,
+      { dimensions: ['category'], measures: ['count', 'total_amount'] },
+      undefined,
+      { previewDrafts: true },
+    );
+    const byCat = Object.fromEntries(result.rows.map((r) => [r.category, r]));
+    expect(byCat.travel).toMatchObject({ count: 2, total_amount: 2000 });
+    expect(byCat.meals).toMatchObject({ count: 2, total_amount: 200 });
+  });
+
+  it('buckets date dimensions by the dataset granularity (month)', async () => {
+    const result = await previewService(SEED_ROWS).queryDataset(
+      DATASET,
+      { dimensions: ['spent_on'], measures: ['total_amount'] },
+      undefined,
+      { previewDrafts: true },
+    );
+    const byMonth = Object.fromEntries(result.rows.map((r) => [r.spent_on, r.total_amount]));
+    expect(byMonth['2026-05']).toBe(2000);
+    expect(byMonth['2026-06']).toBe(200);
+  });
+
+  it('falls through to the real engine when the object has NO pending seed', async () => {
+    // resolver → null ⇒ live-data path ⇒ the bare service (no strategies,
+    // no fallback) rejects — proof the preview branch stepped aside.
+    await expect(
+      previewService(null).queryDataset(
+        DATASET,
+        { dimensions: ['category'], measures: ['count'] },
+        undefined,
+        { previewDrafts: true },
+      ),
+    ).rejects.toThrow();
+  });
+
+  it('ignores the flag entirely when no resolver is configured', async () => {
+    const svc = new AnalyticsService({});
+    await expect(
+      svc.queryDataset(DATASET, { dimensions: [], measures: ['count'] }, undefined, { previewDrafts: true }),
+    ).rejects.toThrow(); // straight to the (absent) engine — no preview detour
+  });
+});
+
+describe('evaluateAnalyticsQueryOverRows', () => {
+  const CUBE: Cube = {
+    name: 'expense_ds',
+    sql: 'expense',
+    dimensions: {
+      category: { name: 'category', type: 'string', sql: 'category' },
+      spent_on: { name: 'spent_on', type: 'time', sql: 'spent_on', granularities: ['month'] },
+    },
+    measures: {
+      count: { name: 'count', type: 'count', sql: '*' },
+      total_amount: { name: 'total_amount', type: 'sum', sql: 'amount' },
+    },
+  } as unknown as Cube;
+
+  it('applies Mongo-style where filters', () => {
+    const r = evaluateAnalyticsQueryOverRows(
+      { measures: ['count'], dimensions: [], where: { category: 'travel' } },
+      CUBE,
+      SEED_ROWS,
+    );
+    expect(r.rows[0].count).toBe(2);
+    expect(
+      evaluateAnalyticsQueryOverRows(
+        { measures: ['count'], dimensions: [], where: { amount: { $gte: 800 } } },
+        CUBE,
+        SEED_ROWS,
+      ).rows[0].count,
+    ).toBe(2);
+  });
+
+  it('filters by timeDimension dateRange and buckets by granularity', () => {
+    const r = evaluateAnalyticsQueryOverRows(
+      {
+        measures: ['total_amount'],
+        dimensions: ['spent_on'],
+        timeDimensions: [{ dimension: 'spent_on', granularity: 'month', dateRange: ['2026-05-01', '2026-05-31'] }],
+      },
+      CUBE,
+      SEED_ROWS,
+    );
+    expect(r.rows).toEqual([{ spent_on: '2026-05', total_amount: 2000 }]);
+  });
+
+  it('orders and limits', () => {
+    const r = evaluateAnalyticsQueryOverRows(
+      { measures: ['total_amount'], dimensions: ['category'], order: { total_amount: 'desc' }, limit: 1 },
+      CUBE,
+      SEED_ROWS,
+    );
+    expect(r.rows).toEqual([{ category: 'travel', total_amount: 2000 }]);
+  });
+
+  it('a zero-dimension query over zero rows still yields one row (count 0)', () => {
+    const r = evaluateAnalyticsQueryOverRows({ measures: ['count'], dimensions: [] }, CUBE, []);
+    expect(r.rows).toEqual([{ count: 0 }]);
+  });
+
+  it('helpers: bucketDate + matchesWhere edge ops', () => {
+    expect(bucketDate('2026-06-11', 'quarter')).toBe('2026-Q2');
+    expect(bucketDate('not-a-date', 'month')).toBeNull();
+    expect(matchesWhere({ a: 'x' }, { $or: [{ a: 'y' }, { a: 'x' }] })).toBe(true);
+    expect(matchesWhere({ a: 5 }, { a: { $in: [1, 5] } })).toBe(true);
+    expect(matchesWhere({ a: 'Hello World' }, { a: { $contains: 'world' } })).toBe(true);
+  });
+});

packages/services/service-analytics/src/analytics-service.ts

@@ -19,6 +19,7 @@ import { ObjectQLStrategy } from './strategies/objectql-strategy.js';
 import { compileDataset, type CompiledDataset, type RelationshipResolver } from './dataset-compiler.js';
 import { DatasetExecutor } from './dataset-executor.js';
 import { resolveDimensionLabels, type DimensionLabelDeps } from './dimension-labels.js';
+import { evaluateAnalyticsQueryOverRows } from './preview-evaluator.js';
 
 /**
  * Configuration for AnalyticsService.
@@ -101,6 +102,20 @@ export interface AnalyticsServiceConfig {
    * by the plugin from the `data` engine; omit to keep raw values.
    */
   labelResolver?: DimensionLabelDeps;
+
+  /**
+   * ADR-0037 Phase 3 — draft data preview. Resolve the PENDING `seed` draft
+   * rows for an object (returns null when the object has no pending seed).
+   * When provided and `queryDataset` is called with `previewDrafts`, the
+   * selection is evaluated over these rows in memory instead of the engine —
+   * the Live Canvas charts real numbers from the drafted sample data, and
+   * because publish materializes the SAME seed, the numbers are continuous
+   * across the publish boundary. Reads only; never touches physical tables.
+   */
+  draftRowsResolver?: (
+    objectName: string,
+    context?: ExecutionContext,
+  ) => Promise<Record<string, unknown>[] | null>;
 }
 
 /**
@@ -142,6 +157,8 @@ export class AnalyticsService implements IAnalyticsService {
   private readonly relationshipResolver?: RelationshipResolver;
   /** Optional dimension display-label resolver (select options / lookup names). */
   private readonly labelResolver?: DimensionLabelDeps;
+  /** ADR-0037 P3: pending-seed row resolver for draft data preview. */
+  private readonly draftRowsResolver?: AnalyticsServiceConfig['draftRowsResolver'];
   readonly cubeRegistry: CubeRegistry;
   private readonly logger: Logger;
 
@@ -157,6 +174,7 @@ export class AnalyticsService implements IAnalyticsService {
     this.readScopeProvider = config.getReadScope;
     this.relationshipResolver = config.relationshipResolver;
     this.labelResolver = config.labelResolver;
+    this.draftRowsResolver = config.draftRowsResolver;
 
     // Compile + register pre-defined datasets (ADR-0021).
     if (config.datasets) {
@@ -341,9 +359,37 @@ export class AnalyticsService implements IAnalyticsService {
     dataset: Dataset,
     selection: DatasetSelection,
     context?: ExecutionContext,
+    options?: { previewDrafts?: boolean },
   ): Promise<AnalyticsResult> {
     const compiled = this.registerDataset(dataset);
     this.logger.debug(`[Analytics] queryDataset "${dataset.name}" (object=${dataset.object}, include=${(dataset.include ?? []).join(',') || '—'})`);
+
+    // ── ADR-0037 P3 — draft data preview ────────────────────────────────────
+    // When the request renders the as-if-published world AND the base object
+    // has a PENDING seed draft, evaluate the selection over the seed's rows in
+    // memory (a query-evaluating proxy feeds the unchanged DatasetExecutor, so
+    // measure filters / compareTo / derived measures all behave identically).
+    // No pending seed → fall through to the real engine: published objects
+    // keep charting live data even inside a preview.
+    if (options?.previewDrafts && this.draftRowsResolver) {
+      let seedRows: Record<string, unknown>[] | null = null;
+      try {
+        seedRows = await this.draftRowsResolver(dataset.object, context);
+      } catch (e) {
+        this.logger.warn(`[Analytics] draft preview resolver failed for "${dataset.object}" — falling back to live data: ${String((e as Error)?.message ?? e)}`);
+      }
+      if (seedRows) {
+        this.logger.debug(`[Analytics] queryDataset "${dataset.name}" → preview over ${seedRows.length} drafted seed row(s)`);
+        const previewService = {
+          query: async (q: AnalyticsQuery) => evaluateAnalyticsQueryOverRows(q, compiled.cube, seedRows!),
+        } as IAnalyticsService;
+        const previewResult = await new DatasetExecutor(previewService).execute(compiled, selection, context);
+        // Label resolution is skipped on purpose: drafted seed rows reference
+        // lookups by NAME (the seed convention), which already reads well.
+        return previewResult;
+      }
+    }
+
     const result = await new DatasetExecutor(this).execute(compiled, selection, context);
 
     // ADR-0021 — resolve grouped dimension values to human display labels

packages/services/service-analytics/src/plugin.ts

@@ -335,6 +335,45 @@ export class AnalyticsServicePlugin implements Plugin {
       },
     };
 
+    // ADR-0037 P3 — draft data preview: resolve the PENDING seed draft's rows
+    // for an object via the kernel protocol (state:'draft' read — a published
+    // seed's rows are already in the real table and must NOT overlay). Lazy
+    // service lookup so plugin order doesn't matter; null ⇒ no pending seed ⇒
+    // queryDataset falls through to live data.
+    const draftRowsResolver = async (objectName: string): Promise<Record<string, unknown>[] | null> => {
+      type ProtocolLike = {
+        getMetaItems?(req: { type: string; previewDrafts?: boolean }): Promise<unknown>;
+        getMetaItem?(req: { type: string; name: string; state?: string }): Promise<unknown>;
+      };
+      let protocol: ProtocolLike | undefined;
+      try {
+        protocol = ctx.getService<ProtocolLike>('protocol');
+      } catch { return null; }
+      if (!protocol?.getMetaItems || !protocol.getMetaItem) return null;
+      const res = await protocol.getMetaItems({ type: 'seed', previewDrafts: true }).catch(() => null);
+      const list = Array.isArray(res)
+        ? res
+        : (res && typeof res === 'object' && Array.isArray((res as { items?: unknown[] }).items)
+          ? (res as { items: unknown[] }).items
+          : []);
+      const rows: Record<string, unknown>[] = [];
+      let pending = false;
+      for (const entry of list) {
+        const body = ((entry as { item?: unknown })?.item ?? entry) as { name?: string; object?: string } | null;
+        if (!body?.name || body.object !== objectName) continue;
+        // Only a PENDING draft row qualifies; getMetaItem({state:'draft'})
+        // throws no_draft when the seed is already published.
+        const draft = await protocol.getMetaItem({ type: 'seed', name: body.name, state: 'draft' }).catch(() => null);
+        const draftBody = (draft as { item?: { records?: unknown[] } } | null)?.item;
+        if (!draftBody) continue;
+        pending = true;
+        for (const r of Array.isArray(draftBody.records) ? draftBody.records : []) {
+          if (r && typeof r === 'object') rows.push(r as Record<string, unknown>);
+        }
+      }
+      return pending ? rows : null;
+    };
+
     const config: AnalyticsServiceConfig = {
       cubes: this.options.cubes,
       logger: ctx.logger,
@@ -346,6 +385,7 @@ export class AnalyticsServicePlugin implements Plugin {
       getAllowedRelationships: this.options.getAllowedRelationships,
       relationshipResolver,
       labelResolver,
+      draftRowsResolver,
     };
 
     if (autoBridgedReadScope) {