Keep the printer's name on statistics after it is deleted (issue #2873)

Every per-printer breakdown resolved the name against the printers that
exist now, so deleting a printer and choosing to keep its prints turned
"Ultron" into "Printer 1" in Prints by Printer, the success-rate and
time-accuracy lists, and Failures by Printer. Archives lose their printer
on that delete as well, so nothing was left to read a name from.

The runs themselves recorded the name they printed on. /archives/stats now
reports the last name each id was known by - taken from the newest run that
has one, so a later name-less row cannot blank it - and failure analysis
falls back to the same thing for ids with no printer left. The client keeps
preferring a live printer's own record, so a rename still shows up straight
away rather than after the next print.

CHANGELOG.md

@@ -5,6 +5,7 @@ All notable changes to Bambuddy will be documented in this file.
 ## [1.2.6b1] - Unreleased
 
 ### Fixed
+- **Statistics forgot the name of a printer that was deleted with its history kept (#2873, reported by @rembomy)** — Prints by Printer, the per-printer success breakdown, the time-accuracy list and Failures by Printer all resolved the name against the printers that exist right now, so deleting a printer and choosing to keep its prints turned "Ultron" into "Printer 1" everywhere. The runs themselves already recorded the name they printed on, and that is what those breakdowns fall back to now: the last name the id was known by, for as long as its prints are kept. A printer that still exists is named from its own record as before, so a rename shows up immediately rather than after the next print. Covered by backend and frontend regression tests.
 - **Skip Objects went dead for the rest of a print if Bambuddy restarted while it was running** — The object list lives in memory and is filled by the print-start path, which is deliberately suppressed on the first status push after a restart so the print is not archived twice. Everything else that moment restores — the archive, filament attribution, the timelapse baseline — came back; the object list did not, so the printer card saw zero objects and greyed out its Skip button. Measured on the maintainer's H2C: 8 objects loaded at 09:02, a restart at 09:17, and no way to skip anything for the remaining hour of the print. Nothing could recover it either, because the one endpoint that can rebuild the list is only reachable from the modal that the greyed-out button opens. The list is now restored on the way back up, from the archive of the print that is still running and matched on the job id the printer mints per print, so a stale archive cannot lend its objects to someone else's job. Two things behind it changed as well: rebuilding now reads the archived 3MF on disk before asking the printer for a file Bambuddy already has — that request was a full transfer off a machine mid-print, 15 MB in this case, and it cannot succeed at all on a printer that kept the file on internal storage — and the card now treats zero objects as "not loaded yet" rather than "nothing to skip", since a running print always has at least one. A single-object print still greys the button out, which is the case that rule was written for. The plate image in the modal came from the same place and had the same problem: the cover, the top view and the object-ID mask all re-fetched the 3MF from the printer after a restart, three fan-outs at once for one modal, so the picture arrived seconds after the list. They now read the running print's archived file too. Wiki updated. Covered by backend and frontend tests.
 - **A print archived without its 3MF can be given its filament weight by hand (#1820, reported by @ojimpo)** — When the sliced file stays somewhere Bambuddy cannot read, the archive is created from the printer's report alone and carries no weight, so the print is missing from every filament total and there was no way to put it right afterwards: Rescan reads the figure out of the 3MF, and that archive has no file to read. The reporter's H2S print left 46 g of PLA on the spool with nothing recording it, and he corrected Spoolman by hand. **Edit Archive** now has a **Filament used (g)** field. It is written to the print's most recent run as well as to the archive, because the Projects roll-up and the Prometheus counter sum the runs rather than the cards — correcting only the card would have fixed the display and left every aggregate reading the old figure. The value is bounded at 0 to 100 kg, it is sent only when you actually change it, so an ordinary save cannot round off a sliced figure, and emptying the field clears it. A run that measured its own weight through spool tracking keeps that measurement — the correction fills in a run that has none, or one that only ever inherited the archive's estimate, and never overwrites a real measurement with a typed one. Nothing is deducted from Spoolman or internal inventory either: those are charged from what was tracked at the time, and a print that recorded nothing has nothing to reverse. On an archive that does have its 3MF, Rescan still overwrites what you typed — there the file is the authority. Translated in all locales; wiki updated. Covered by backend and frontend tests.
 - **The internal-storage probe now logs which directory served the file (#1820)** — When a printer says a print went to internal storage and Bambuddy finds it over FTPS anyway (#2856), the log said which file but not where it came from. On a printer that keeps uploads for weeks — the reporter's H2S has months of them in `/cache` — a reprint of a name that was re-sliced but never re-sent can match an older copy, and without the directory in the log that mismatch was invisible rather than merely rare. The download helper now reports the path that served the file instead of a bare success flag, and the hit line names it. Covered by backend tests.

backend/app/api/routes/archives.py

@@ -1177,6 +1177,30 @@ async def get_archive_stats(
     )
     prints_by_printer = {str(k): v for k, v in printer_result.all()}
 
+    # Names for printers the client can no longer look up. The breakdowns above
+    # key on the id each run recorded, and deleting a printer while keeping its
+    # history leaves that id pointing at nothing, so a chart that used to read
+    # "Ultron" fell back to "Printer 1" (#2873). Every run also stored the name
+    # it printed on, so the last one recorded is what that id was called. The
+    # client still prefers a live printer's current name, which keeps a rename
+    # showing up straight away.
+    last_named_run = (
+        select(func.max(PrintLogEntry.id).label("entry_id"))
+        .where(
+            PrintLogEntry.printer_id.isnot(None),
+            PrintLogEntry.printer_name.isnot(None),
+            *base_conditions,
+        )
+        .group_by(PrintLogEntry.printer_id)
+        .subquery()
+    )
+    name_result = await db.execute(
+        select(PrintLogEntry.printer_id, PrintLogEntry.printer_name).join(
+            last_named_run, PrintLogEntry.id == last_named_run.c.entry_id
+        )
+    )
+    printer_names = {str(printer_id): name for printer_id, name in name_result.all()}
+
     # Time accuracy — compare each completed run's actual duration to the
     # slicer's estimate on the linked archive. Runs without a linked archive
     # (NULL archive_id) or without an estimate are excluded.
@@ -1276,6 +1300,7 @@ async def get_archive_stats(
         total_cost=round(total_cost, 2),
         prints_by_filament_type=prints_by_filament,
         prints_by_printer=prints_by_printer,
+        printer_names=printer_names,
         average_time_accuracy=average_accuracy,
         time_accuracy_by_printer=accuracy_by_printer if accuracy_by_printer else None,
         total_energy_kwh=round(total_energy_kwh, 3),

backend/app/schemas/archive.py

@@ -173,6 +173,10 @@ class ArchiveStats(BaseModel):
     total_cost: float
     prints_by_filament_type: dict
     prints_by_printer: dict
+    # Name each printer id was last recorded under in the print log. Lets the
+    # client keep labelling history that belongs to a deleted printer (#2873);
+    # a printer that still exists is named from the live record instead.
+    printer_names: dict[str, str] = {}
     # Time accuracy stats
     # Average across all prints with data
     average_time_accuracy: float | None = None

backend/app/services/failure_analysis.py

@@ -151,6 +151,25 @@ class FailureAnalysisService:
                 select(Printer.id, Printer.name).where(Printer.id.in_(failures_by_printer_id.keys()))
             )
             printer_names = {row[0]: row[1] for row in printers_result.fetchall()}
+            # A printer deleted with its history kept has no row left to read a
+            # name from, and "Printer 3" tells nobody which machine kept failing
+            # (#2873). Each run recorded the name it printed on, so fall back to
+            # the last one that id was known by.
+            missing = [pid for pid in failures_by_printer_id if pid not in printer_names]
+            if missing:
+                last_named_run = (
+                    select(func.max(PrintLogEntry.id).label("entry_id"))
+                    .where(PrintLogEntry.printer_id.in_(missing), PrintLogEntry.printer_name.isnot(None))
+                    .group_by(PrintLogEntry.printer_id)
+                    .subquery()
+                )
+                historic_result = await self.db.execute(
+                    select(PrintLogEntry.printer_id, PrintLogEntry.printer_name).join(
+                        last_named_run, PrintLogEntry.id == last_named_run.c.entry_id
+                    )
+                )
+                for pid, name in historic_result.fetchall():
+                    printer_names[pid] = name
             failures_by_printer = {
                 printer_names.get(pid, f"Printer {pid}"): count for pid, count in failures_by_printer_id.items()
             }

backend/tests/integration/test_deleted_printer_keeps_name_2873.py

@@ -0,0 +1,112 @@
+"""Statistics keeps naming a printer that was deleted with its history (#2873).
+
+Deleting a printer while keeping its prints leaves the log rows pointing at an
+id nothing resolves any more, so every per-printer breakdown fell back to
+"Printer 1" for machines the reporter knew as "Ultron". Each run recorded the
+name it printed on, so that is what the aggregates report now.
+"""
+
+from __future__ import annotations
+
+from datetime import datetime, timedelta
+
+import pytest
+from httpx import AsyncClient
+
+from backend.app.models.print_log import PrintLogEntry
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_stats_name_history_of_a_deleted_printer(async_client: AsyncClient, db_session):
+    base = datetime(2026, 7, 15, 10, 0, 0)
+    db_session.add_all(
+        [
+            PrintLogEntry(
+                printer_id=71,
+                printer_name="Ultron",
+                status="completed",
+                started_at=base,
+                completed_at=base + timedelta(hours=1),
+                duration_seconds=3600,
+            ),
+            PrintLogEntry(
+                printer_id=71,
+                printer_name="Ultron",
+                status="failed",
+                started_at=base + timedelta(hours=2),
+                completed_at=base + timedelta(hours=3),
+                duration_seconds=3600,
+            ),
+        ]
+    )
+    await db_session.commit()
+
+    stats = (await async_client.get("/api/v1/archives/stats")).json()
+
+    assert stats["prints_by_printer"]["71"] == 2
+    assert stats["printer_names"]["71"] == "Ultron"
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_stats_reports_the_last_name_the_printer_ran_under(async_client: AsyncClient, db_session):
+    """A printer renamed before it was deleted is remembered by its last name."""
+    base = datetime(2026, 7, 15, 10, 0, 0)
+    db_session.add_all(
+        [
+            PrintLogEntry(printer_id=71, printer_name="Ultron", status="completed", started_at=base),
+            PrintLogEntry(
+                printer_id=71,
+                printer_name="Ultron Mk II",
+                status="completed",
+                started_at=base + timedelta(days=1),
+            ),
+            # A run logged before names were recorded must not blank the label.
+            PrintLogEntry(printer_id=71, printer_name=None, status="completed", started_at=base + timedelta(days=2)),
+        ]
+    )
+    await db_session.commit()
+
+    stats = (await async_client.get("/api/v1/archives/stats")).json()
+
+    assert stats["printer_names"]["71"] == "Ultron Mk II"
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_stats_names_do_not_override_a_live_printer(async_client: AsyncClient, db_session, printer_factory):
+    """Renaming a printer that still exists shows up straight away.
+
+    The client prefers the live record, so the historical name only has to be
+    present, not authoritative.
+    """
+    printer = await printer_factory(name="Renamed Later")
+    db_session.add(PrintLogEntry(printer_id=printer.id, printer_name="Original Name", status="completed"))
+    await db_session.commit()
+
+    stats = (await async_client.get("/api/v1/archives/stats")).json()
+    printers = (await async_client.get("/api/v1/printers/")).json()
+
+    assert stats["printer_names"][str(printer.id)] == "Original Name"
+    assert [p["name"] for p in printers if p["id"] == printer.id] == ["Renamed Later"]
+
+
+@pytest.mark.asyncio
+@pytest.mark.integration
+async def test_failure_analysis_names_a_deleted_printer(async_client: AsyncClient, db_session, printer_factory):
+    """Failures by printer reads the recorded name once the printer is gone."""
+    live = await printer_factory(name="Still Here")
+    db_session.add_all(
+        [
+            PrintLogEntry(printer_id=71, printer_name="Ultron", status="failed"),
+            PrintLogEntry(printer_id=live.id, printer_name="Older Name", status="failed"),
+        ]
+    )
+    await db_session.commit()
+
+    analysis = (await async_client.get("/api/v1/archives/analysis/failures")).json()
+
+    assert analysis["failures_by_printer"]["Ultron"] == 1
+    assert analysis["failures_by_printer"]["Still Here"] == 1
+    assert "Printer 71" not in analysis["failures_by_printer"]

frontend/src/__tests__/pages/StatsPage.test.tsx

@@ -2,7 +2,7 @@
  * Tests for the StatsPage component.
  */
 
-import { describe, it, expect, beforeEach } from 'vitest';
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
 import { screen, waitFor } from '@testing-library/react';
 import { render } from '../utils';
 import { StatsPage } from '../../pages/StatsPage';
@@ -621,4 +621,46 @@ describe('StatsPage', () => {
       expect(printTime?.querySelector('svg[aria-label]')).toBeNull();
     });
   });
+
+  describe('deleted printers (#2873)', () => {
+    // The per-printer breakdown only renders at half width, and the dashboard
+    // reads its sizes back from localStorage.
+    const halfWidthSuccessRate = JSON.stringify({
+      order: ['success-rate'],
+      hidden: [],
+      sizes: { 'success-rate': 2 },
+    });
+
+    afterEach(() => {
+      vi.mocked(localStorage.getItem).mockReset();
+    });
+
+    it('labels history from a deleted printer with the name it ran under', async () => {
+      vi.mocked(localStorage.getItem).mockImplementation((key: string) =>
+        key === 'bambusy-dashboard-layout-v2' ? halfWidthSuccessRate : null
+      );
+      server.use(
+        http.get('/api/v1/archives/stats', () =>
+          HttpResponse.json({
+            ...mockStats,
+            // Printer 7 was deleted with its prints kept, so it is missing from
+            // /printers and used to show as "Printer 7".
+            prints_by_printer: { '1': 100, '7': 12 },
+            printer_names: { '1': 'Name At The Time', '7': 'Ultron' },
+          })
+        )
+      );
+
+      render(<StatsPage />);
+
+      await waitFor(() => {
+        expect(screen.getByText('Ultron')).toBeInTheDocument();
+      });
+      expect(screen.queryByText('Printer 7')).not.toBeInTheDocument();
+      // A printer that still exists is named from the live record instead, so a
+      // rename shows up without waiting for the next print.
+      expect(screen.getAllByText('X1 Carbon').length).toBeGreaterThan(0);
+      expect(screen.queryByText('Name At The Time')).not.toBeInTheDocument();
+    });
+  });
 });

frontend/src/api/client.ts

@@ -813,6 +813,9 @@ export interface ArchiveStats {
   total_cost: number;
   prints_by_filament_type: Record<string, number>;
   prints_by_printer: Record<string, number>;
+  // Name each printer id was last recorded under in the print log, so history
+  // belonging to a deleted printer keeps its label.
+  printer_names?: Record<string, string>;
   average_time_accuracy: number | null;
   time_accuracy_by_printer: Record<string, number> | null;
   total_energy_kwh: number;

frontend/src/pages/StatsPage.tsx

@@ -1103,7 +1103,18 @@ export function StatsPage() {
   const isRefetching = (isStatsFetching || isArchivesFetching) && !isLoading;
 
   const currency = getCurrencySymbol(settings?.currency || 'USD');
-  const printerMap = new Map(printers?.map((p) => [String(p.id), p.name]) || []);
+  // History outlives the printer that made it: a deleted printer is gone from
+  // `printers`, so its rows fell back to "Printer 1" (#2873). The stats response
+  // carries the name each id was last recorded under; a printer that still
+  // exists overrides it, so a rename shows up straight away.
+  const printerMap = useMemo(
+    () =>
+      new Map<string, string>([
+        ...Object.entries(stats?.printer_names || {}),
+        ...(printers?.map((p) => [String(p.id), p.name] as [string, string]) || []),
+      ]),
+    [stats?.printer_names, printers],
+  );
   const printDates = useMemo(() => archives?.map((a) => a.created_at) || [], [archives]);
 
   if (isLoading) {

static/index.html

@@ -26,7 +26,7 @@
 
     <!-- Splash screens for iOS -->
     <link rel="apple-touch-startup-image" href="/img/android-chrome-512x512.png" />
-    <script type="module" crossorigin src="/assets/index-CVKc5Khd.js"></script>
+    <script type="module" crossorigin src="/assets/index-DwcyDXDd.js"></script>
     <link rel="stylesheet" crossorigin href="/assets/index-kSJGQrMr.css">
   </head>
   <body>