fix: badblocks progress tracks overall %, not per-phase (1.0.0-42)

`badblocks -w` cycles through 4 patterns (0xaa, 0x55, 0xff, 0x00),
each with a write phase + a verify phase = 8 phases. The output's
"XX% done" lines are per-phase, so the dashboard appeared to "rewind"
every ~2 hours. Two drives racing each other could look 4× apart in
displayed progress despite identical hardware — actually one was
just further into a later phase.

New _BadblocksProgress state machine watches for "Testing with
pattern 0xXX" and "Reading and comparing" headers, advances the
phase counter, and reports overall = ((phase-1) * 100 + phase_pct) / 8
clipped to 99. Pure state machine, no I/O.

7 new tests cover phase-header detection, boundary math, monotonicity
across a synthetic stream, and the original "two drives at same
per-phase % look identical" bug.

Image rebuilt and tagged but NOT deployed to the running container —
4 surface-validate jobs are 20-95% through 14TB drives and a recreate
would SIGHUP the remote badblocks processes. Deploy with
`docker compose up -d` after the current batch finishes.

app/burnin/stages.py

@@ -25,6 +25,72 @@ class _BadblocksResult(TypedDict):
     aborted: bool
 
 
+# `badblocks -w` cycles through 4 patterns (0xaa, 0x55, 0xff, 0x00),
+# each with a write phase followed by a read-back/verify phase = 8 phases.
+# Per-phase percent comes back via `XX% done`; without translation, the
+# dashboard appears to "rewind" every ~2 hours when a new phase starts.
+_BB_PATTERN_PHASE = {"0xaa": 1, "0x55": 3, "0xff": 5, "0x00": 7}
+_BB_TOTAL_PHASES = 8
+
+import re as _re_pre  # noqa: E402
+
+_BB_PATTERN_RE = _re_pre.compile(r"Testing with pattern\s+(0x[0-9a-fA-F]+)")
+_BB_VERIFY_RE = _re_pre.compile(r"Reading and comparing")
+_BB_PERCENT_RE = _re_pre.compile(r"([\d.]+)%\s+done")
+
+
+class _BadblocksProgress:
+    """Track which phase of `badblocks -w -p N` we're in so the
+    displayed percent maps to overall progress, not per-phase progress.
+
+    Pure state machine — no I/O. Feed it lines from the badblocks output
+    via :meth:`update`; read :attr:`overall_pct` after each call.
+
+    Behavior:
+    - Defaults to phase 1 (write 0xaa) before any header is seen.
+    - "Testing with pattern 0xXX" sets the phase to the write-phase index
+      for that pattern (1, 3, 5, or 7).
+    - "Reading and comparing" advances to the matching verify phase
+      (last_write_phase + 1).
+    - "XX% done" updates the in-phase percent.
+    - overall_pct = ((phase - 1) * 100 + phase_pct) / 8, clipped to 99
+      so we don't claim "100%" until the stage's success path explicitly
+      writes 100.
+    """
+
+    __slots__ = ("phase", "phase_pct", "_last_write_phase")
+
+    def __init__(self) -> None:
+        self.phase: int = 1
+        self.phase_pct: float = 0.0
+        self._last_write_phase: int = 1
+
+    def update(self, line: str) -> None:
+        m = _BB_PATTERN_RE.search(line)
+        if m:
+            p = m.group(1).lower()
+            if p in _BB_PATTERN_PHASE:
+                self.phase = _BB_PATTERN_PHASE[p]
+                self._last_write_phase = self.phase
+                self.phase_pct = 0.0
+            return
+        if _BB_VERIFY_RE.search(line):
+            self.phase = self._last_write_phase + 1
+            self.phase_pct = 0.0
+            return
+        m = _BB_PERCENT_RE.search(line)
+        if m:
+            try:
+                self.phase_pct = float(m.group(1))
+            except ValueError:
+                pass
+
+    @property
+    def overall_pct(self) -> int:
+        total = (self.phase - 1) * 100.0 + self.phase_pct
+        return min(99, int(total / _BB_TOTAL_PHASES))
+
+
 def _build_badblocks_cmd(devname: str) -> str:
     """Construct the wrapped badblocks command for a given device.
 
@@ -425,9 +491,8 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
             #
             cmd = _build_badblocks_cmd(devname)
             async with conn.create_process(cmd) as proc:
-                import re as _re
-
                 pid_seen = False
+                progress = _BadblocksProgress()
 
                 async def _drain(stream, is_stderr: bool):
                     nonlocal bad_blocks_total, pid_seen
@@ -451,10 +516,16 @@ async def _stage_surface_validate_ssh(job_id: int, devname: str, drive_id: int)
                         output_lines.append(line)
 
                         if is_stderr:
-                            m = _re.search(r"([\d.]+)%\s+done", line)
-                            if m:
-                                pct = min(99, int(float(m.group(1))))
-                                await _update_stage_percent(job_id, "surface_validate", pct)
+                            # Drive progress.update from EVERY stderr line so it
+                            # picks up the "Testing with pattern 0xXX" + "Reading
+                            # and comparing" headers (which advance the phase
+                            # counter), not just the percent-done lines.
+                            prev = progress.overall_pct
+                            progress.update(line)
+                            if progress.overall_pct != prev or _BB_PERCENT_RE.search(line):
+                                await _update_stage_percent(
+                                    job_id, "surface_validate", progress.overall_pct,
+                                )
                                 await _update_stage_bad_blocks(job_id, "surface_validate", bad_blocks_total)
                                 await _recalculate_progress(job_id)
                                 _push_update()

app/config.py

@@ -83,7 +83,7 @@ class Settings(BaseSettings):
     ssh_key: str = ""             # PEM private key content (paste full key including headers)
 
     # Application version — used by the /api/v1/updates/check endpoint
-    app_version: str = "1.0.0-41"
+    app_version: str = "1.0.0-42"
 
     # ---- Authentication (1.0.0-22) ----
     # session_secret: HMAC key for signing session cookies. Empty = generate

tests/test_badblocks_progress.py

@@ -0,0 +1,125 @@
+"""Verifies _BadblocksProgress translates per-phase badblocks output
+into a monotonic 0-99% overall progress.
+
+`badblocks -w` cycles through 4 patterns × {write, verify} = 8 phases.
+Each phase prints "XX% done" relative to its own 0-100 range. Without
+this translation the dashboard appeared to "rewind" every ~2 hours
+when a new phase started — and two drives racing each other could
+look 4× apart in displayed progress despite identical hardware.
+
+Run inside the container image so app deps are present.
+"""
+
+from __future__ import annotations
+
+import unittest
+
+from app.burnin.stages import _BadblocksProgress
+
+
+class TestBadblocksProgress(unittest.TestCase):
+
+    def test_default_phase_one(self):
+        """Before any header, treat as start of pattern-1 write."""
+        p = _BadblocksProgress()
+        self.assertEqual(p.phase, 1)
+        self.assertEqual(p.overall_pct, 0)
+
+    def test_pattern_headers_set_phase(self):
+        """0xaa→1, 0x55→3, 0xff→5, 0x00→7 (write phases)."""
+        p = _BadblocksProgress()
+        for header, want in [
+            ("Testing with pattern 0xaa: ", 1),
+            ("Testing with pattern 0x55: ", 3),
+            ("Testing with pattern 0xff: ", 5),
+            ("Testing with pattern 0x00: ", 7),
+        ]:
+            p.update(header)
+            self.assertEqual(p.phase, want, f"after {header!r}")
+
+    def test_verify_advances_to_next_phase(self):
+        """`Reading and comparing` after `Testing with pattern 0x55`
+        (phase 3) advances to phase 4."""
+        p = _BadblocksProgress()
+        p.update("Testing with pattern 0x55: 100.00% done")
+        self.assertEqual(p.phase, 3)
+        p.update("Reading and comparing: 0.00% done")
+        self.assertEqual(p.phase, 4)
+
+    def test_overall_pct_at_phase_boundaries(self):
+        """Verify the math at each phase boundary: phase N at 100% =
+        N * 12.5% overall (clipped to 99 at the end)."""
+        cases = [
+            (1,   0.0,  0),   # start of run
+            (1, 100.0, 12),   # 100/800 = 12.5
+            (2, 100.0, 25),   # 200/800
+            (4, 100.0, 50),   # 400/800
+            (7, 100.0, 87),   # 700/800
+            (8, 100.0, 99),   # 800/800 → clipped to 99
+        ]
+        for phase, phase_pct, want in cases:
+            p = _BadblocksProgress()
+            p.phase = phase
+            p.phase_pct = phase_pct
+            self.assertEqual(
+                p.overall_pct, want,
+                f"phase={phase} phase_pct={phase_pct}",
+            )
+
+    def test_realistic_sequence(self):
+        """End-to-end: feed a synthetic badblocks output stream and
+        check the overall percent stays monotonically non-decreasing."""
+        lines = [
+            "Testing with pattern 0xaa: ",
+            "10.00% done, 1:00:00 elapsed. (0/0/0 errors)",
+            "50.00% done, 5:00:00 elapsed. (0/0/0 errors)",
+            "99.99% done, 10:00:00 elapsed. (0/0/0 errors)",
+            "Reading and comparing: ",
+            "0.00% done, 10:00:01 elapsed. (0/0/0 errors)",
+            "50.00% done, 12:30:00 elapsed. (0/0/0 errors)",
+            "Testing with pattern 0x55: ",
+            "0.00% done, 15:00:00 elapsed. (0/0/0 errors)",
+            "50.00% done, 17:30:00 elapsed. (0/0/0 errors)",
+        ]
+        p = _BadblocksProgress()
+        seen = []
+        for line in lines:
+            p.update(line)
+            seen.append(p.overall_pct)
+        self.assertEqual(
+            seen, sorted(seen),
+            f"progress went backwards: {seen}",
+        )
+        # Sanity: by the time we're halfway through pattern-2 write
+        # (phase 3, 50%), we should report ((3-1)*100 + 50) / 8 = 31%.
+        self.assertEqual(seen[-1], 31)
+
+    def test_drives_at_different_phases_show_different_overall(self):
+        """The original bug: two drives at the same per-phase 60%
+        but different phases used to look identical (both '60%').
+        Now they correctly diverge."""
+        slow = _BadblocksProgress()
+        slow.update("Testing with pattern 0xaa: ")
+        slow.update("60.00% done")
+
+        fast = _BadblocksProgress()
+        fast.update("Testing with pattern 0xaa: ")
+        fast.update("99.99% done")
+        fast.update("Reading and comparing: ")
+        fast.update("60.00% done")
+
+        # slow: 60/800 = 7%; fast: (1*100 + 60)/800 = 20%
+        self.assertEqual(slow.overall_pct, 7)
+        self.assertEqual(fast.overall_pct, 20)
+
+    def test_unknown_pattern_does_not_crash(self):
+        """An unrecognized pattern (e.g. badblocks future versions or
+        custom patterns) just leaves phase unchanged."""
+        p = _BadblocksProgress()
+        p.update("Testing with pattern 0xab: ")
+        # phase stays at the default 1
+        self.assertEqual(p.phase, 1)
+
+
+if __name__ == "__main__":
+    unittest.main()