A demo does not need a tunnel; it needs the laptop's own camera

Asked after the mobile-internet question: could a VPN let the office cameras
be shown in the demo. Three jobs get confused there and only one needs one.

Seeing the estate from anywhere already works and needs nothing - viewer mode
plus LiveHub is exactly that, outbound, no installation and no credential.

Demonstrating recognition is better done on the demo machine's own camera.
`webcam: 0` picks a capture index instead of building an RTSP URL and the
engine has supported it since the first version: CameraStore round-trips it,
source() returns the index, safe_url() reports webcam:0, and
POST /api/cameras {"id":"laptop","webcam":0} has always worked. No screen
offered it - the same gap this repo already records for the customer record
and per-camera tuning. It is now an option in the make picker, and it is the
strongest demo available: real faces, in the room, depending on no network.
A demo pointed at a camera in another building depends on two internet
connections and a tunnel staying up while somebody is talking.

The address and the index are alternatives, not extras: source() takes the
webcam first, so a half-typed host left behind would make the saved camera
describe two things and use one. The scan, the path and the camera password
are hidden for a local camera because none of them mean anything.

A tunnel is still right for one case - running the engine on a remote machine
against the office's own cameras - and still wrong for the product: it is
per-site infrastructure on every shop PC, and it gives head office
network-level access into a customer's LAN, where today we can read a
camera's picture and nothing else.

Also: installing httpx took the suite from 239 passed to 271. The HTTP tests
importorskip it so a bare checkout runs, which means the number at the bottom
of a run is not the number of tests that exist. Added to the dev extra.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KGcjxF1cNLcuwc3DAPcnfj

CLAUDE.md

@@ -3599,3 +3599,206 @@ is not up yet and a shop PC showing a stopped engine for five minutes after
 install looks broken. `tests/test_model_download.py` asserts them, and the
 rewritten fetch was checked against the real URL: 232,589 bytes, sha256
 identical to the model already on disk.
+
+## The engine stopped updating, and said "installed" every time
+
+The SSL fix above was released and **did not reach the machine it was written
+for**. Its log said so, one line above the tick:
+
+```
+behavision is already installed with the same version as the provided wheel.
+Use --force-reinstall to force an installation of the wheel.
+ [ok] Engine and dependencies installed
+```
+
+and the traceback that followed still pointed at `model_assets.py", line 59,
+in _fetch / urllib.request.urlretrieve` — code the fix had deleted.
+
+Two frozen literals caused it: `version = "1.1.0"` in `pyproject.toml` and
+`__version__ = "1.0.0"` in `behavision/__init__.py`. They disagreed with each
+other and neither tracked a release, so **every release built
+`behavision-1.1.0-py3-none-any.whl`** and `pip install --upgrade` on a machine
+that already had 1.1.0 is a no-op. The comment beside that call even claimed
+the opposite: *"`--upgrade` so re-running after a new release replaces the
+engine rather than leaving the old one in place and reporting success."*
+
+The shape of the damage is what makes it bad. The Go binaries — the app, the
+agent, the setup tool — are rebuilt every release and updated normally. So a
+shop PC ran a current app supervising an engine several releases old, and
+nothing anywhere said which: `/api/health` reported the model, the paths, the
+cameras and the gallery, and **no version at all**.
+
+Three changes, and the second is the one that does not depend on the first
+being remembered:
+
+- **One version, in the package**, read by `pyproject.toml` through
+  `[tool.setuptools.dynamic]`. Two literals in two files is how they came to
+  disagree. In a checkout it reads `0.0.0+dev`, because a plausible-looking
+  number on a developer's `/api/health` would be worse than none.
+- **`pip install --force-reinstall --no-deps <wheel>`, after the ordinary
+  `--upgrade`.** `--upgrade` settles the dependencies; the second call
+  guarantees our own code is the code in the folder. `--no-deps` is what keeps
+  it cheap — forcing the dependencies too would re-download ~300 MB of numpy,
+  OpenCV and onnxruntime on every run. A rebuild at an unchanged version is the
+  ordinary case while developing, so this must not rely on the version moving.
+- **`release.sh` stamps the tag**: `v0.5.6-demo` → `0.5.6+demo`, valid PEP 440
+  (a local segment takes alphanumerics and dots, never hyphens). Into a copy of
+  the line, reverted in a `trap`, so the tree is never left dirty.
+
+`/api/health` reports `version` now. Without it there is no way to tell a shop
+PC three releases behind from a current one, which is precisely how this
+survived several releases.
+
+Reproduced end to end before fixing, against real wheels on Python 3.12: two
+builds of the same version, `--upgrade` leaves the old code in place and prints
+the same sentence the colleague's Mac printed, `--force-reinstall --no-deps`
+replaces it.
+
+### `urllib` does not let `SSLCertVerificationError` out, and a fake said it did
+
+The certificate fix above shipped and **failed on the machine it was written
+for, with the exact traceback it was meant to prevent**. The retry was written
+
+```python
+except ssl.SSLCertVerificationError:
+```
+
+and urllib never raises that from `urlopen`. It catches it and re-raises
+`urllib.error.URLError(err)`, carrying the original on `.reason`. So the
+`except` matched nothing, ever, and the fallback could not fire.
+
+The unit test passed throughout, because the stub it used raised the bare SSL
+error — **a shape real urllib never produces**. That is the whole lesson: a
+fake that agrees with the author is worse than no test, because it converts an
+untested path into a tested-looking one. The same sentence is already in this
+file about `UPDATE ... RETURNING` and about the in-memory API fake, and it was
+written again here anyway.
+
+`_is_cert_failure` checks the exception **and** its `.reason`, and the tests
+now raise `URLError(SSLCertVerificationError(...))`, which is what his
+traceback shows. A plain `URLError` — "no route to host" — is re-raised
+untouched: retrying that with a different CA list changes nothing except how
+long the operator waits for the real message, and a test asserts the second
+attempt never happens.
+
+Beside the stubs there is now a **real** reproduction,
+`test_against_a_real_machine_with_no_trust_store`, opt-in behind
+`BEHAVISION_NETWORK_TESTS=1` because it reaches github.com. Python's default
+context honours `SSL_CERT_FILE`, so pointing it at an empty file gives a
+default context that trusts nobody — the python.org condition exactly — while
+certifi is loaded by path and is unaffected.
+
+It skips rather than passes where it cannot reproduce that, and the difference
+is measured rather than assumed:
+
+```
+macOS Command Line Tools  LibreSSL 2.8.3   128 CAs with SSL_CERT_FILE empty
+                                           (reads the system keychain)
+python.org / pyenv build  OpenSSL 3.5.8      0 CAs  -> reproduces it
+```
+
+Checked for teeth by putting the shipped `except` back: both the corrected stub
+test and the live one fail, and pass again when it is restored.
+
+## "The cameras won't connect from my mobile internet" — and why that is not a bug
+
+Asked directly by the owner, about his own cameras, from his phone's
+connection. The answer is physics, and the product was not giving it.
+
+A camera lives on the shop's LAN behind a router. `192.168.1.121` means
+*"something on the network I am attached to"* and nothing more — from mobile
+data, a hotel, or head office it resolves to nobody, or to a completely
+different device that happens to hold that number. There is no route in from
+the internet and **there must not be**: an RTSP camera reachable from outside
+is how a shop's cameras end up being watched by strangers.
+
+This is the reason the product is split the way it is, and it is worth stating
+plainly next to the split itself: the shop PC is the only machine on the
+camera's LAN, so it does the connecting, and every other surface reaches it
+**outbound** — the agent's pull, the arrivals feed, and `LiveHub`'s frame relay,
+which is what makes **Watch live** work from anywhere while nothing connects in.
+
+What was wrong is the message. `cannot reach 192.168.1.121:554 - Operation
+timed out` reads as a broken camera and sends somebody to re-type an address
+and a password that were always correct. `_wrong_network_hint` now names the
+cause, and it distinguishes two states that need opposite actions — the same
+rule as `artifact` against `no_faces`, and `stale` against `not_connecting`:
+
+| | |
+|---|---|
+| this computer **is** on that network | check the camera is powered on and that the address is right |
+| this computer is **somewhere else** | the computer is in the wrong place; no setting here fixes it, recognition has to run on a machine in the shop |
+
+- **The local address comes from a `connect`ed UDP socket** that sends nothing.
+  It only fixes a route so the kernel will name the source address — no packet
+  leaves, and it needs no dependency in an engine that already ships 200 MB of
+  models.
+- **The LAN ranges are spelled out, not `is_private`.** That property is
+  broader than "an address on somebody's LAN": it also covers carrier-grade NAT
+  and the documentation networks (192.0.2, 198.51.100, 203.0.113), and telling
+  somebody who typed one of those that it is "on the shop's own network" is a
+  confident wrong answer in the place people look first. Found by a test using
+  `203.0.113.9` as its example of a *public* address, which `is_private` calls
+  private.
+- **A DNS name gets no hint at all.** Nothing can be concluded about
+  `camera.local` from the string, and guessing is the failure mode this whole
+  message exists to fix.
+- **With no network at all it still names the cause** and drops the comparison,
+  rather than claiming to know which network this machine is on.
+
+## A tunnel for the demo: when it is the right answer, and when it is not
+
+Asked after the mobile-internet question: *"what if we created a secure tunnel
+or vpn, then the cameras in our office can be shown in the demo version too?"*
+
+Three different jobs get confused here, and only one of them needs a tunnel.
+
+**Seeing the estate from anywhere already works and needs nothing.** Viewer
+mode plus `LiveHub` is exactly this: the shop PC pushes frames outbound and any
+signed-in app sees them, from mobile data, a hotel or a customer's office. A
+VPN would add an installation, a credential and a moving part to something that
+already works with none of them.
+
+**Demonstrating recognition is better done on the demo machine's own camera.**
+`webcam: 0` picks a capture index instead of building an RTSP URL, and the
+engine has supported it since the first version — `CameraStore` round-trips it,
+`source()` returns the index, `safe_url()` reports `webcam:0`, and
+`POST /api/cameras {"id":"laptop","webcam":0}` has always worked. **No screen
+offered it**, which is the same gap this file already records for the customer
+record and for per-camera tuning: the API could, the UI could not reach it.
+
+It is now an option in the make picker, and it is the strongest demo available:
+real faces, in the room, instant, depending on no network at all. A demo
+pointed at a camera in another building depends on two internet connections and
+a tunnel staying up while somebody is talking.
+
+**The one case a tunnel genuinely answers** is running the engine on a remote
+machine against the office's own cameras — LAN access to `192.168.1.121` from
+somewhere that is not that LAN. A mesh VPN (Tailscale and similar) does that
+honestly: a subnet router at the office, the client on the demo machine, and
+the address works unchanged. Free at this scale, no port forwarding, no
+exposed camera. Worth using for our *own* office when that is really the goal.
+
+**It is still the wrong answer for the product**, and the reasons are not about
+difficulty:
+
+- It is per-site infrastructure — an account, a node, a key — on every shop PC
+  we ship, to replace something that already works over ordinary HTTPS.
+- It gives head office **network-level access into a customer's LAN**. The
+  current design can read a camera's picture; a VPN can reach the customer's
+  till, their router and everything else on that network. That is a far larger
+  thing to be trusted with, and a far larger thing to have breached.
+- The failure modes are worse and less legible: a tunnel that is down looks
+  like a camera that is down.
+
+So: tunnel for our own office if we want the engine running remotely; nothing
+at all for showing customers their shops; the laptop's own camera for showing
+anybody what the product does.
+
+### And the suite was quietly 32 tests smaller than it looked
+
+Installing `httpx` to check the webcam path took the engine suite from **239
+passed to 271**. `tests/test_api_cameras.py` and its siblings begin with
+`pytest.importorskip("httpx")` so a bare checkout still runs — deliberate, and
+it means the number at the bottom of a run is not the number of tests that
+exist. `pip install -e .[dev]` is the opt-in.

agent/cmd/behavision-setup/main.go

@@ -539,7 +539,30 @@ func pipInstall(vpy, src string) error {
 	// 'behavision.egg-info': Read-only file system". Falling back to source
 	// copies it somewhere writable first, for the same reason.
 	if wheels, _ := filepath.Glob(filepath.Join(src, "behavision-*.whl")); len(wheels) > 0 {
-		return stream(exec.Command(vpy, "-m", "pip", "install", "--upgrade", wheels[0]),
+		// TWO calls, and the second is the one that matters.
+		//
+		// `--upgrade` alone is not an upgrade when the version has not moved:
+		// pip skips the wheel and says so, one line above this program
+		// printing "[ok] Engine and dependencies installed". The wheel version
+		// was a frozen literal for several releases, so every engine fix in
+		// them silently failed to reach any machine that had run setup once -
+		// while the Go binaries beside it, rebuilt every release, updated
+		// normally. Half the product current, half of it months old, and
+		// nothing saying which.
+		//
+		// release.sh stamps the tag into the version now, so the versions do
+		// differ. This does not rely on that: a rebuild at the same version is
+		// the ordinary case while developing, and "installed" has to mean the
+		// code in this folder either way.
+		if err := stream(exec.Command(vpy, "-m", "pip", "install", "--upgrade", wheels[0]),
+			"installing the engine"); err != nil {
+			return err
+		}
+		// --no-deps so this is our own package only: the call above has
+		// already settled the dependencies, and forcing those too would
+		// re-download ~300 MB of numpy, OpenCV and onnxruntime every run.
+		return stream(exec.Command(vpy, "-m", "pip", "install",
+			"--force-reinstall", "--no-deps", wheels[0]),
 			"installing the engine")
 	}
 	tmp, err := os.MkdirTemp("", "behavision-src-")

behavision/__init__.py

@@ -4,4 +4,15 @@ Pipeline: capture -> detect (YuNet) -> track (IoU) -> align + encode
 (ArcFace ONNX) -> match / auto-enroll (FAISS + SQLite) -> events + API.
 """
 
-__version__ = "1.0.0"
+# Stamped by release.sh from the git tag, into a copy of this line, so a
+# release always produces a wheel nobody has installed before. It was a frozen
+# "1.0.0" here and a frozen "1.1.0" in pyproject.toml - two literals that
+# disagreed with each other and tracked nothing - which is how every engine fix
+# for several releases silently failed to reach a machine that had run setup
+# once. pip skips a wheel whose version is already installed and says so, one
+# line above setup printing "[ok] Engine and dependencies installed".
+#
+# In a checkout it stays obviously a checkout: "0.0.0+dev" on /api/health is
+# the truth about a developer's machine, and a plausible-looking number there
+# would be worse than none.
+__version__ = "0.0.0+dev"

behavision/api.py

@@ -17,6 +17,7 @@ from fastapi.responses import HTMLResponse, Response, StreamingResponse
 from fastapi.security import HTTPBasic, HTTPBasicCredentials
 from pydantic import BaseModel, ValidationError
 
+from . import __version__
 from .config import ApiSection, CameraConfig, CameraTuning
 from .commission import CommissionRun
 from .events import Event
@@ -142,7 +143,7 @@ def _reencode(jpeg: bytes, width: int, quality: int) -> "bytes | None":
 
 
 def create_app(engine: Engine) -> FastAPI:
-    app = FastAPI(title="Behavision", version="1.0.0",
+    app = FastAPI(title="Behavision", version=__version__,
                   dependencies=_auth_dependencies(engine.cfg.api))
 
     def worker_or_404(camera_id: str):
@@ -172,6 +173,10 @@ def create_app(engine: Engine) -> FastAPI:
         # are up, and the shop recognises nobody it already knows.
         stranded = engine.gallery.health["stranded"]
         return {"status": "ok" if engine.started_at else "starting",
+                # Which build is actually running. Without it there was no way
+                # to tell a shop PC three releases behind from a current one -
+                # which is precisely how a silent install failure survived.
+                "version": __version__,
                 "recognition_model": engine.encoder.model_name,
                 "gallery_unreadable_embeddings": stranded,
                 # "where is my database" must be answerable from the API: the

behavision/capture.py

@@ -68,6 +68,78 @@ os.environ.setdefault(
 STALL_AFTER_S = 10.0
 
 
+def _local_ipv4() -> str:
+    """This machine's address on the interface holding the default route.
+
+    A UDP socket is `connect`ed and nothing is sent - it only fixes a route so
+    the kernel will name the source address. No packet leaves, and it needs no
+    dependency, which matters in an engine that already ships 200 MB of models.
+    """
+    import socket
+    try:
+        with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as s:
+            s.settimeout(0.5)
+            s.connect(("8.8.8.8", 80))
+            return s.getsockname()[0]
+    except OSError:
+        return ""
+
+
+def _wrong_network_hint(host: str) -> str:
+    """Why a private camera address is unreachable, when that is the reason.
+
+    A camera lives on the shop's LAN behind a router, and 192.168.x.x means
+    "something on the network I am attached to" - nothing more. From mobile
+    data, a hotel, or head office it either resolves to nobody or to a
+    completely different device that happens to hold that number. There is no
+    route in from the internet and there must not be: an RTSP camera reachable
+    from outside is how a shop's cameras end up being watched by strangers.
+
+    Without this the answer was "cannot reach 192.168.1.121:554 - Operation
+    timed out", which reads as a broken camera and sends somebody to re-type
+    an address and a password that were always correct. Asked directly by the
+    owner, about his own cameras, from his phone's connection.
+
+    Two states, two different actions, so they must not share a sentence: on
+    the same network the camera or its address is the problem; on a different
+    one the COMPUTER is in the wrong place and no setting will fix it.
+    """
+    import ipaddress
+    try:
+        addr = ipaddress.ip_address(host)
+    except ValueError:
+        return ""  # a DNS name; nothing can be concluded from the string
+    # The RFC1918 blocks and link-local, spelled out rather than `is_private`.
+    # That property is broader than "an address on somebody's LAN": it also
+    # covers the carrier-grade NAT range and the documentation networks
+    # (192.0.2, 198.51.100, 203.0.113), and telling somebody who typed one of
+    # those that it is "on the shop's own network" would be a confident wrong
+    # answer in the place people look first. Found by a test using 203.0.113.9
+    # as an example of a PUBLIC address, which `is_private` calls private.
+    lan = any(addr in ipaddress.ip_network(n) for n in
+              ("10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16", "169.254.0.0/16")
+              if addr.version == 4)
+    if not lan:
+        return ""
+
+    mine = _local_ipv4()
+    if not mine:
+        return (" - that is a private address, reachable only from inside "
+                "the network the camera is on")
+    try:
+        same = ipaddress.ip_network(f"{mine}/24", strict=False).supernet_of(
+            ipaddress.ip_network(f"{host}/24", strict=False))
+    except (ValueError, TypeError):
+        same = False
+    if same:
+        return (f" - this computer is on that network ({mine}), so check the "
+                f"camera is powered on and that {host} is its address")
+    return (f" - this computer is on {mine}, not the camera's network. A "
+            f"private address like {host} is only reachable from inside the "
+            f"shop's own network, never over the internet or mobile data, so "
+            f"recognition has to run on a computer in the shop")
+
+
 def _tcp_reachable(source: "str | int", timeout: float
                    ) -> "tuple[bool, str]":
     """Cheap pre-flight for an rtsp:// URL. Non-URL sources pass through."""
@@ -85,10 +157,11 @@ def _tcp_reachable(source: "str | int", timeout: float
             return True, ""
     except socket.timeout:
         return False, (f"no response from {parsed.hostname}:{port} within "
-                       f"{timeout:.0f}s - check the IP address and that the "
-                       f"camera is on the same network")
+                       f"{timeout:.0f}s{_wrong_network_hint(parsed.hostname)}")
     except OSError as exc:
-        return False, f"cannot reach {parsed.hostname}:{port} - {exc.strerror or exc}"
+        return False, (f"cannot reach {parsed.hostname}:{port} - "
+                       f"{exc.strerror or exc}"
+                       f"{_wrong_network_hint(parsed.hostname)}")
 
 
 def _fourcc(cap) -> str:

behavision/model_assets.py

@@ -5,6 +5,7 @@ from __future__ import annotations
 import logging
 import shutil
 import ssl
+import urllib.error
 import urllib.request
 from pathlib import Path
 
@@ -65,6 +66,27 @@ def _https_context() -> "ssl.SSLContext | None":
     return ssl.create_default_context(cafile=certifi.where())
 
 
+def _is_cert_failure(err: BaseException) -> bool:
+    """Is this a certificate-verification failure, however it is wrapped?
+
+    `urllib` does NOT let `ssl.SSLCertVerificationError` out. It catches it and
+    re-raises `urllib.error.URLError(err)`, carrying the original on `.reason`
+    - so `except ssl.SSLCertVerificationError` around `urlopen` matches
+    nothing, ever.
+
+    That is not a subtlety this file gets to record academically: the first
+    version of the fallback below was written exactly that way, shipped, and
+    failed on the machine it was written for with the very traceback it was
+    meant to prevent. The unit test passed throughout, because the fake it
+    used raised the bare SSL error - a shape real urllib never produces. A
+    stub that agrees with the author is worse than no test, and the test now
+    raises what urllib raises.
+    """
+    reason = getattr(err, "reason", None)
+    return isinstance(err, ssl.SSLCertVerificationError) or \
+        isinstance(reason, ssl.SSLCertVerificationError)
+
+
 def _urlopen(url: str, timeout: float = 60.0):
     """Open a URL, falling back to certifi's CA bundle on a verify failure.
 
@@ -75,7 +97,13 @@ def _urlopen(url: str, timeout: float = 60.0):
     """
     try:
         return urllib.request.urlopen(url, timeout=timeout)
-    except ssl.SSLCertVerificationError:
+    except (urllib.error.URLError, ssl.SSLCertVerificationError) as err:
+        # Only a certificate problem is worth a second attempt. "No route to
+        # host" and "connection refused" arrive as URLError too, and retrying
+        # those with a different CA list changes nothing except how long the
+        # operator waits for the real message.
+        if not _is_cert_failure(err):
+            raise
         ctx = _https_context()
         if ctx is None:
             raise

desktop/frontend/dist/index.html

@@ -4,7 +4,7 @@
     <meta charset="UTF-8" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <title>Behavision</title>
-    <script type="module" crossorigin src="./assets/index-6LYbNlbD.js"></script>
+    <script type="module" crossorigin src="./assets/index-DSNu_2FW.js"></script>
     <link rel="stylesheet" crossorigin href="./assets/index-DOJ2bRrM.css">
   </head>
   <body>

desktop/frontend/src/views/Cameras.jsx

@@ -14,6 +14,18 @@ import { MAKES, makeById } from '../../../../shared/cameraMakes.js'
 // signed off through.
 const BLANK = { id: '', host: '', port: 554, path: '', username: '', password: '', max_width: 1280 }
 
+// "This computer's own camera" - a webcam or a built-in FaceTime camera.
+//
+// The engine has supported it since the first version (`webcam: 0` picks a
+// capture index instead of building an RTSP URL) and no screen has ever
+// offered it: another case of the API being able to do something the UI
+// could not reach. It matters most for the thing it was missing from, which
+// is showing the product to somebody. A laptop's own camera gives real
+// recognition, of real faces, in the room, depending on no network at all -
+// where pointing a demo machine at a camera in another building depends on
+// two internet connections and a tunnel staying up while you talk.
+const WEBCAM = 'webcam'
+
 export default function Cameras() {
   const { data, error, reload } = usePolled(() => api.cameras(), 8000)
   const [editing, setEditing] = useState(null)
@@ -190,7 +202,9 @@ function useStreamURLs(cams) {
 function CameraSheet({ cam, onClose, onSaved }) {
   const isNew = !cam.id
   const [f, setF] = useState({ ...BLANK, ...cam, password: '', path: cam.path || (isNew ? MAKES[0].path : '') })
-  const [make, setMake] = useState(isNew ? MAKES[0].id : 'manual')
+  const [make, setMake] = useState(isNew ? MAKES[0].id : (cam.webcam != null ? WEBCAM : 'manual'))
+  const [index, setIndex] = useState(cam.webcam != null ? String(cam.webcam) : '0')
+  const local = make === WEBCAM
   const [test, setTest] = useState(null)
   const [busy, setBusy] = useState(null)
   const [error, setError] = useState(null)
@@ -199,6 +213,7 @@ function CameraSheet({ cam, onClose, onSaved }) {
   // Only overwrite the path when the preset has one, so choosing "I know the
   // path" does not wipe what the installer already typed.
   function chooseMake(e) {
+    if (e.target.value === WEBCAM) { setMake(WEBCAM); setTest(null); return }
     const m = makeById(e.target.value)
     setMake(m.id)
     setF(prev => ({ ...prev, path: m.path || prev.path }))
@@ -212,6 +227,14 @@ function CameraSheet({ cam, onClose, onSaved }) {
       if (v === '' || v === null || v === undefined) continue
       out[k] = (k === 'port' || k === 'max_width') ? Number(v) : v
     }
+    if (local) {
+      // An address and a webcam index are alternatives, not extras: the
+      // engine's source() takes the webcam first, so leaving a half-typed
+      // host behind would make the saved camera describe two different
+      // things and only one of them would be used.
+      for (const k of ['host', 'path', 'username', 'password']) delete out[k]
+      out.webcam = Number(index) || 0
+    }
     return out
   }
 
@@ -259,7 +282,7 @@ function CameraSheet({ cam, onClose, onSaved }) {
           <p className="lead">Three things from the camera: its address, its make, and its password. Test before you save — a wrong address is the most common mistake.</p>
           {error && <div className="err"><Icon.Warning size={15} />{error}</div>}
 
-          {isNew && (
+          {isNew && !local && (
             <section className="formsection">
               <h4>Find it</h4>
               {scan === null && (
@@ -301,15 +324,20 @@ function CameraSheet({ cam, onClose, onSaved }) {
                 <em className="hint">Short, no spaces. It names this camera everywhere and cannot be changed later.</em>
               </label>
             )}
-            <div className="fieldrow">
-              <label className="field"><span>Address</span>
-                <input value={f.host} onChange={set('host')} placeholder="192.168.1.20" inputMode="decimal" />
-                <em className="hint">On a label on the camera, or in its own app under “network”.</em>
-              </label>
-              <label className="field narrow"><span>Port</span>
-                <input value={f.port} onChange={set('port')} inputMode="numeric" />
-              </label>
-            </div>
+            {local
+              ? <label className="field narrow"><span>Camera number</span>
+                  <input value={index} onChange={e => { setIndex(e.target.value); setTest(null) }} inputMode="numeric" />
+                  <em className="hint">0 is the built-in camera. Try 1 if a second one is plugged in.</em>
+                </label>
+              : <div className="fieldrow">
+                  <label className="field"><span>Address</span>
+                    <input value={f.host} onChange={set('host')} placeholder="192.168.1.20" inputMode="decimal" />
+                    <em className="hint">On a label on the camera, or in its own app under “network”.</em>
+                  </label>
+                  <label className="field narrow"><span>Port</span>
+                    <input value={f.port} onChange={set('port')} inputMode="numeric" />
+                  </label>
+                </div>}
           </section>
 
           <section className="formsection">
@@ -317,27 +345,34 @@ function CameraSheet({ cam, onClose, onSaved }) {
             <label className="field"><span>Make of camera</span>
               <select value={make} onChange={chooseMake}>
                 {MAKES.map(m => <option key={m.id} value={m.id}>{m.label}</option>)}
+                <option value={WEBCAM}>This computer’s own camera</option>
               </select>
-              {chosen.note && <em className="hint">{chosen.note}</em>}
-            </label>
-            <label className="field"><span>Stream path</span>
-              <input className="mono" value={f.path} onChange={set('path')} placeholder="/Streaming/Channels/101" />
-              <em className="hint">Filled in from the make. Change it only if the camera’s own app says something else.</em>
+              {local
+                ? <em className="hint">Recognition runs on this computer’s built-in or plugged-in camera. Nothing on the network is involved.</em>
+                : chosen.note && <em className="hint">{chosen.note}</em>}
             </label>
+            {!local && (
+              <label className="field"><span>Stream path</span>
+                <input className="mono" value={f.path} onChange={set('path')} placeholder="/Streaming/Channels/101" />
+                <em className="hint">Filled in from the make. Change it only if the camera’s own app says something else.</em>
+              </label>
+            )}
           </section>
 
-          <section className="formsection">
-            <h4>Sign-in to the camera</h4>
-            <div className="fieldrow">
-              <label className="field"><span>Username</span>
-                <input name="rtsp-account" autoComplete="off" value={f.username} onChange={set('username')} placeholder="admin" />
-              </label>
-              <label className="field"><span>Password</span>
-                <input type="password" name="rtsp-secret" autoComplete="new-password" value={f.password}
-                       onChange={set('password')} placeholder={cam.has_password ? '(unchanged)' : ''} />
-              </label>
-            </div>
-          </section>
+          {!local && (
+            <section className="formsection">
+              <h4>Sign-in to the camera</h4>
+              <div className="fieldrow">
+                <label className="field"><span>Username</span>
+                  <input name="rtsp-account" autoComplete="off" value={f.username} onChange={set('username')} placeholder="admin" />
+                </label>
+                <label className="field"><span>Password</span>
+                  <input type="password" name="rtsp-secret" autoComplete="new-password" value={f.password}
+                         onChange={set('password')} placeholder={cam.has_password ? '(unchanged)' : ''} />
+                </label>
+              </div>
+            </section>
+          )}
 
           {test && (
             test.ok

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "behavision"
-version = "1.1.0"
+dynamic = ["version"]
 description = "Production face recognition over RTSP"
 requires-python = ">=3.10"
 dependencies = [
@@ -22,7 +22,11 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
-dev = ["pytest>=8.0"]
+# httpx is test-only and never ships in the wheel. The HTTP tests begin with
+# `pytest.importorskip("httpx")` so a bare checkout still runs - which is
+# right, and has a cost worth knowing: without it the suite reports 239 passed
+# and quietly SKIPS 32 API tests. `pip install -e .[dev]` is how to get them.
+dev = ["pytest>=8.0", "httpx>=0.27"]
 
 [tool.setuptools.packages.find]
 include = ["behavision*"]
@@ -32,3 +36,9 @@ behavision = ["static/*"]
 
 [tool.pytest.ini_options]
 testpaths = ["tests"]
+
+# One version for the package and the wheel. Two literals in two files is how
+# they came to disagree (1.0.0 here, 1.1.0 there) and how neither tracked a
+# release.
+[tool.setuptools.dynamic]
+version = {attr = "behavision.__version__"}

release.sh

@@ -50,7 +50,28 @@ step "2. Agent and setup tool"
 step "3. Engine source and wheel"
 # The wheel is built with the checkout's own interpreter; requires-python is a
 # statement about the SHOP PC, which setup enforces when it finds Python there.
+# Stamp the tag into the wheel version. Without this every release built
+# behavision-1.1.0-py3-none-any.whl, and `pip install --upgrade` on a machine
+# that already had 1.1.0 is a no-op - so an engine fix reached nobody who had
+# ever run setup, while the Go binaries beside it updated normally. Nothing
+# reported a version either, so there was no way to tell a shop PC three
+# releases behind from a current one.
+#
+# v0.5.6-demo -> 0.5.6+demo, which is valid PEP 440: a local segment takes
+# alphanumerics and dots, never hyphens.
+TMPVER=$(mktemp)
+PEP440=$(printf '%s' "${TAG#v}" | sed 's/-/+/; s/[^0-9A-Za-z.+]/./g')
+trap 'git checkout -- behavision/__init__.py 2>/dev/null || true; rm -f "$TMPVER"' EXIT
+# A temp file rather than `sed -i`, whose argument handling differs between
+# BSD and GNU - this script is run from a Mac today and that is not a reason
+# to plant a portability trap in a release path.
+sed "s/^__version__ = .*/__version__ = \"$PEP440\"/" behavision/__init__.py > "$TMPVER"
+cat "$TMPVER" > behavision/__init__.py
 .venv/bin/python -m pip wheel --no-deps --ignore-requires-python -q -w "$STAGE/engine-src" . 2>&1 | grep -v "DEPRECATION\|WARNING: Ignoring" || true
+git checkout -- behavision/__init__.py
+rm -f "$TMPVER"
+trap - EXIT
+echo "   engine wheel version $PEP440"
 ls "$STAGE"/engine-src/behavision-*.whl >/dev/null || { echo "wheel was not built" >&2; exit 1; }
 cp pyproject.toml requirements.txt "$STAGE/engine-src/"
 mkdir -p "$STAGE/engine-src/config" && cp config/default.yaml "$STAGE/engine-src/config/"

tests/test_api_cameras.py

@@ -225,3 +225,42 @@ def test_an_inverted_per_camera_pair_is_rejected_not_stored(client):
              tuning={"enroll_threshold": 0.8, "match_threshold": 0.5})
     assert r.status_code == 400
     assert c.get("/api/cameras").json() == []
+
+
+# "This computer's own camera" — the demo case, and a capability the engine
+# has always had with nothing able to reach it.
+#
+# It matters most for showing the product to somebody. A laptop's own camera
+# gives real recognition, of real faces, in the room, depending on no network
+# at all — where pointing a demo machine at a camera in another building
+# depends on two internet connections and a tunnel staying up while you talk.
+def test_this_computers_own_camera_can_be_added(client):
+    c, eng = client
+    r = c.post("/api/cameras", json={"id": "laptop", "webcam": 0})
+    assert r.status_code == 201, r.text
+    assert "laptop" in eng.workers
+
+    cam = next(x for x in c.get("/api/cameras").json() if x["id"] == "laptop")
+    # Returned, or the form cannot tell a webcam camera from a half-filled
+    # RTSP one when somebody opens it to edit.
+    assert cam["webcam"] == 0
+    assert eng.camera_store.get("laptop").source() == 0
+
+
+def test_a_second_camera_index_is_kept(client):
+    """0 is the built-in one; a plugged-in camera is usually 1. An index
+    silently coerced to 0 would open the wrong camera and look like the
+    setting had no effect."""
+    c, eng = client
+    assert c.post("/api/cameras", json={"id": "usb", "webcam": 1}).status_code == 201
+    assert eng.camera_store.get("usb").source() == 1
+
+
+def test_a_webcam_camera_survives_a_reload(client, tmp_path):
+    """It has to be on disk, not only in the running engine: a demo that
+    forgets its camera when the app restarts is worse than no demo."""
+    c, _ = client
+    c.post("/api/cameras", json={"id": "laptop", "webcam": 0})
+    again = CameraStore(tmp_path / "cameras.json").get("laptop")
+    assert again.source() == 0
+    assert again.safe_url() == "webcam:0"

tests/test_model_download.py

@@ -9,6 +9,7 @@ perfectly - numpy, onnxruntime, faiss, all of it - and then could not fetch a
 """
 import io
 import logging
+import os
 import ssl
 import urllib.request
 
@@ -33,9 +34,18 @@ class _Resp(io.BytesIO):
 
 
 def _verify_error():
-    return ssl.SSLCertVerificationError(
+    """What urlopen ACTUALLY raises, which is not what it looks like.
+
+    urllib catches ssl.SSLCertVerificationError and re-raises
+    urllib.error.URLError(err), carrying the original on `.reason`. The first
+    version of this test raised the bare SSL error - a shape real urllib never
+    produces - so it passed against a fallback that could never fire, and the
+    fix shipped and failed on the machine it was written for with the exact
+    traceback it was meant to prevent.
+    """
+    return urllib.error.URLError(ssl.SSLCertVerificationError(
         "[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: "
-        "unable to get local issuer certificate")
+        "unable to get local issuer certificate"))
 
 
 def test_a_machine_with_no_trust_store_falls_back_to_the_bundled_one(monkeypatch):
@@ -74,12 +84,22 @@ def test_a_working_trust_store_is_used_as_is(monkeypatch):
 
 
 def test_a_real_network_failure_is_not_disguised_as_a_certificate_problem(monkeypatch):
+    """A URLError is not automatically a certificate problem.
+
+    "No route to host" and "connection refused" arrive as URLError too, and
+    retrying those with a different CA list changes nothing except how long
+    the operator waits for the real message.
+    """
+    calls = []
+
     def fake(url, timeout=None, context=None):
+        calls.append(context)
         raise urllib.error.URLError("no route to host")
 
     monkeypatch.setattr(urllib.request, "urlopen", fake)
     with pytest.raises(urllib.error.URLError):
         model_assets._urlopen("https://example.invalid/m.onnx")
+    assert calls == [None], f"a dead network was retried as a CA problem: {calls}"
 
 
 def test_progress_lines_survive_the_rewrite(tmp_path, monkeypatch, caplog):
@@ -103,3 +123,42 @@ def test_progress_lines_survive_the_rewrite(tmp_path, monkeypatch, caplog):
     pct = [ln for ln in lines if ln.startswith("download: face detector ")]
     assert pct, f"no progress lines at all: {lines}"
     assert "download: face detector 100%" in pct, pct
+
+
+@pytest.mark.skipif(not os.environ.get("BEHAVISION_NETWORK_TESTS"),
+                    reason="set BEHAVISION_NETWORK_TESTS=1 to reach github.com")
+def test_against_a_real_machine_with_no_trust_store(tmp_path, monkeypatch):
+    """The whole thing, over the real network, with the real failure.
+
+    Every stub above is a statement about what I believe urllib does, and the
+    first version of this file proved how much that is worth. Python's default
+    context honours SSL_CERT_FILE, so pointing it at an EMPTY file reproduces
+    a python.org macOS build exactly: a default context that trusts nobody.
+    certifi is loaded by path and is unaffected by the variable, so if the
+    fallback works here it works there.
+    """
+    empty = tmp_path / "no-cas.pem"
+    empty.write_text("")
+    monkeypatch.setenv("SSL_CERT_FILE", str(empty))
+    monkeypatch.setenv("SSL_CERT_DIR", str(tmp_path / "nothing"))
+
+    # Not every interpreter can be put into that state, and pretending
+    # otherwise would turn this into a test that passes by not running. A
+    # Python linked against LibreSSL - which is what macOS Command Line Tools
+    # ships - reads the system keychain and ignores SSL_CERT_FILE entirely:
+    # measured, 128 CAs loaded with the variable pointing at an empty file. A
+    # python.org build links OpenSSL and honours it: 0 CAs, which is the
+    # condition being reproduced.
+    if ssl.create_default_context().get_ca_certs():
+        pytest.skip("this interpreter ignores SSL_CERT_FILE (%s), so the "
+                    "no-trust-store condition cannot be reproduced here"
+                    % ssl.OPENSSL_VERSION)
+
+    # The premise: the default context really is broken in this process.
+    with pytest.raises(urllib.error.URLError) as caught:
+        urllib.request.urlopen(model_assets.YUNET_URL, timeout=30)
+    assert model_assets._is_cert_failure(caught.value), caught.value
+
+    dest = tmp_path / "yunet.onnx"
+    model_assets._fetch(model_assets.YUNET_URL, dest, "face detector")
+    assert dest.stat().st_size > 200_000

tests/test_wrong_network.py

@@ -0,0 +1,81 @@
+"""Why a camera "will not connect", when the real answer is that the computer
+asking is in the wrong building.
+
+Asked directly by the owner, about his own cameras, from his phone's
+connection: *"when i connect from my mobile internet the cameras wont connect,
+why is that"*. The answer was `cannot reach 192.168.1.121:554 - Operation
+timed out`, which reads as a broken camera and sends somebody to re-type an
+address and a password that were always correct.
+"""
+import pytest
+
+from behavision import capture
+
+
+@pytest.fixture
+def on(monkeypatch):
+    def _set(ip):
+        monkeypatch.setattr(capture, "_local_ipv4", lambda: ip)
+    return _set
+
+
+def test_a_different_network_says_so_and_says_what_to_do(on):
+    on("10.11.12.13")  # a phone's tethered network
+    hint = capture._wrong_network_hint("192.168.1.121")
+    assert "not the camera's network" in hint
+    # The action, not just the diagnosis: no setting on this screen fixes it.
+    assert "computer in the shop" in hint
+
+
+def test_the_same_network_sends_you_to_the_camera_instead(on):
+    on("192.168.1.120")
+    hint = capture._wrong_network_hint("192.168.1.121")
+    assert "on that network" in hint
+    assert "powered on" in hint
+    # Two states that need opposite actions must not share a sentence.
+    assert "not the camera's network" not in hint
+
+
+@pytest.mark.parametrize("host", [
+    "8.8.8.8",        # plainly routable
+    "203.0.113.9",    # TEST-NET-3: `is_private` calls this private, and it is
+                      # not a LAN address - which is why the check spells out
+                      # the RFC1918 blocks instead of asking is_private
+    "100.64.0.5",     # carrier-grade NAT, what a mobile network hands out
+])
+def test_an_address_that_is_not_a_lan_address_gets_no_hint(on, host):
+    """A routable address unreachable from here is an ordinary network fault,
+    and inventing a story about private networks would be wrong."""
+    on("192.168.1.120")
+    assert capture._wrong_network_hint(host) == ""
+
+
+def test_a_name_gets_no_hint(on):
+    """Nothing can be concluded about `camera.local` from the string, and a
+    guess here is a confident wrong answer in the place people look first."""
+    on("192.168.1.120")
+    assert capture._wrong_network_hint("camera.local") == ""
+
+
+def test_loopback_gets_no_hint(on):
+    on("192.168.1.120")
+    assert capture._wrong_network_hint("127.0.0.1") == ""
+
+
+def test_with_no_network_at_all_it_still_names_the_cause(on):
+    """A machine with no route cannot say which network it is on, and must not
+    pretend: the private-address fact is still true and still the reason."""
+    on("")
+    hint = capture._wrong_network_hint("192.168.1.121")
+    assert "private address" in hint
+    assert "this computer is on" not in hint
+
+
+def test_the_hint_reaches_the_message_a_person_reads():
+    """The whole point is the sentence on the screen, not a helper nobody
+    calls. Port 1 on a private address refuses or times out immediately."""
+    ok, msg = capture._tcp_reachable("rtsp://192.168.1.121:1/ch0", 1.0)
+    assert not ok
+    assert "192.168.1.121" in msg
+    # Whichever branch the OS takes, the explanation travels with it.
+    assert "network" in msg