Files
saphid--frame-control/ui/frame_devices.py
T
saphidandClaude Opus 5.5 cb182dbce5 Devices: fixes from review round 3
- Attempts carry a generation: one overtaken by a switch, a removal or a login
  change routes nothing back to the old headset and can't report connected.
- Removing the active headset or changing its user/port reroutes at once,
  before anything that can fail.
- One known_hosts file per headset (~/.ssh/frame-control-hosts/<id>):
  forgetting one headset's key can't drop another's, whoever else writes.
- learn() checks, under the config lock, that the block is still what the
  attempt started from before writing to it.
- A switch stops live video and drops captures from the previous headset.
- A probe shares its time between the addresses a name resolves to.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
2026-09-28 21:48:39 +10:00

709 lines
28 KiB
Python

"""The headsets Frame Control knows, and the addresses each can be reached at.
One headset can answer at several addresses: a LAN IP at home, another in the
office, its mDNS name (frame.local), its Tailscale IP or MagicDNS name. The
registry keeps them all, learns which worked on which network, and hands the
connector (frame_link.py) an order to try them in.
Stored as JSON in frame_host.data_dir("devices.json"). The format is plain so the
iPhone app can share it later; docs/devices.md describes it:
{"version": 1, "active": "<device id>",
"devices": [{"id", "name", "alias", "user", "port", "identity_files",
"addresses": [{"host", "kind": lan|mdns|tailscale|manual, "label",
"networks": [network ids it worked on], "last_ok", "last_rtt_ms"}]}],
"networks": {"<network id>": {"name", "ssid", "gateway", "gateway_mac", "last_seen"}}}
Headsets set up before this existed live only in ~/.ssh/config, in the managed
`# >>> steam-frame (ALIAS) >>>` blocks that scripts/connect.sh and
ui/frame_connect.py write; they're imported from there, so nobody has to add
them again. Each device keeps its alias: Terminal's `ssh frame` and the helper
scripts go on working, and the connector rewrites the block's HostName to the
last address that worked, so they follow it.
Host keys are pinned per headset, not per address: ssh gets
`-o HostKeyAlias=frame-control-<id>` and a known_hosts file of the headset's own
(~/.ssh/frame-control-hosts/<id>), so a different device answering at a
remembered IP is caught.
Python stdlib only.
"""
import contextlib
import copy
import json
import os
import re
import secrets
import subprocess
import tempfile
import threading
import time
from pathlib import Path
import frame_host
import frame_network
VERSION = 1
# Everything here can end up in ssh arguments or ~/.ssh/config, so nothing that
# could start an option, add a line, or carry a directive.
NAME_RE = re.compile(r"[A-Za-z0-9][A-Za-z0-9._-]{0,63}")
HOST_RE = re.compile(r"[A-Za-z0-9:][A-Za-z0-9.:-]{0,252}(%[A-Za-z0-9._-]{1,32})?")
TEXT_MAX = 60
KINDS = ("lan", "mdns", "tailscale", "manual")
KIND_LABEL = {"lan": "Local network", "mdns": "mDNS (.local)", "tailscale": "Tailscale", "manual": "Other"}
DEFAULT_USER = "steamos"
class DeviceError(ValueError):
"""Bad input from the page; the server answers 400 with the message."""
def ssh_dir():
"""~/.ssh, or $FRAME_CONTROL_SSH_DIR in tests so they never touch the real one."""
return Path(os.environ.get("FRAME_CONTROL_SSH_DIR") or Path.home() / ".ssh")
def ssh_config():
return ssh_dir() / "config"
PIN_DIR = "frame-control-hosts"
def known_hosts(device_id):
"""The headset's own known_hosts file: one per headset, so saving or forgetting one
headset's key (by ssh or by the app) can never touch another's."""
return ssh_dir() / PIN_DIR / device_id
def known_hosts_opt(device_id):
"""How ssh is told about it. `~` rather than the full path when it's the usual
place, so a home folder with a space in its name can't split the option."""
if os.environ.get("FRAME_CONTROL_SSH_DIR"):
return str(known_hosts(device_id))
return f"~/.ssh/{PIN_DIR}/{device_id}"
def host_key_alias(device_id):
return f"frame-control-{device_id}"
# ---- validation ----------------------------------------------------------------
def check_alias(alias):
if not isinstance(alias, str) or not NAME_RE.fullmatch(alias):
raise DeviceError("The SSH alias must be a plain name: letters, digits, dot, dash or underscore")
return alias
def check_user(user):
if not isinstance(user, str) or not NAME_RE.fullmatch(user):
raise DeviceError("The user name must be letters, digits, dot, dash or underscore")
return user
def check_host(host):
host = host.strip() if isinstance(host, str) else host
if (not isinstance(host, str) or not HOST_RE.fullmatch(host) or ".." in host
or ("%" in host and ":" not in host.split("%")[0])): # a zone only follows an IPv6 address
raise DeviceError(f"{host!r} isn't a host name or IP address")
return host
def check_port(port):
try:
port = int(port)
except (TypeError, ValueError):
raise DeviceError("The port must be a number") from None
if not 1 <= port <= 65535:
raise DeviceError("The port must be between 1 and 65535")
return port
def check_text(text, what):
text = (text or "").strip() if isinstance(text, (str, type(None))) else None
if text is None or len(text) > TEXT_MAX or re.search(r"[\x00-\x1f\x7f]", text):
raise DeviceError(f"The {what} must be plain text of at most {TEXT_MAX} characters")
return text
def check_kind(kind):
if kind not in KINDS:
raise DeviceError(f"The kind must be one of {', '.join(KINDS)}")
return kind
def ssh_host(host):
"""A host for ssh's HostName, which expands %-tokens: an IPv6 zone's % is doubled."""
return host.replace("%", "%%")
# ---- ~/.ssh/config's managed blocks ---------------------------------------------
BLOCK_RE = re.compile(r"# >>> steam-frame \((" + NAME_RE.pattern + r")\) >>>")
def begin_mark(alias):
return f"# >>> steam-frame ({alias}) >>>"
def end_mark(alias):
return f"# <<< steam-frame ({alias}) <<<"
def parse_blocks(text):
"""The managed blocks: [{"alias", "hostname", "user", "port", "identity_files"}]."""
blocks, cur = [], None
for line in text.splitlines():
m = BLOCK_RE.fullmatch(line.strip())
if m:
cur = {"alias": m.group(1), "hostname": None, "user": None, "port": 22, "identity_files": []}
continue
if cur is None:
continue
if line.strip() == end_mark(cur["alias"]):
blocks.append(cur)
cur = None
continue
f = line.split(None, 1)
if len(f) != 2:
continue
key, value = f[0].lower(), f[1].strip()
if key == "hostname" and cur["hostname"] is None:
cur["hostname"] = value.replace("%%", "%")
elif key == "user" and cur["user"] is None:
cur["user"] = value
elif key == "port" and value.isdigit():
cur["port"] = int(value)
elif key == "identityfile":
cur["identity_files"].append(value)
return blocks
def read_config(path=None):
path = Path(path or ssh_config())
try:
return path.read_text(encoding="utf-8")
except (OSError, UnicodeDecodeError):
return ""
# One edit of ~/.ssh/config at a time: between this app's threads (_config_lock) and
# with Set Up Connection (frame_connect.py and scripts/connect.sh take the same lock
# file). _edit_config also notices any other program writing in between.
_config_lock = threading.Lock()
LOCK_NAME = "config.frame-control.lock"
@contextlib.contextmanager
def file_lock(path, timeout=30):
"""An exclusive lock on `path` (created if need be) shared with other processes:
POSIX record locks (what zsh's `zsystem flock` takes), or msvcrt on Windows."""
path.parent.mkdir(parents=True, exist_ok=True)
fh = open(path, "a+")
try:
deadline = time.monotonic() + timeout
while True:
try:
if frame_host.WINDOWS:
import msvcrt
fh.seek(0)
msvcrt.locking(fh.fileno(), msvcrt.LK_NBLCK, 1)
else:
import fcntl
fcntl.lockf(fh, fcntl.LOCK_EX | fcntl.LOCK_NB)
break
except OSError:
if time.monotonic() > deadline:
raise OSError(f"{path} stayed locked (is Set Up Connection running?)")
time.sleep(0.1)
yield
finally:
try:
if frame_host.WINDOWS:
import msvcrt
fh.seek(0)
msvcrt.locking(fh.fileno(), msvcrt.LK_UNLCK, 1)
else:
import fcntl
fcntl.lockf(fh, fcntl.LOCK_UN)
except OSError:
pass
fh.close()
def _write_config(path, text, expected):
"""Swap the file in whole (as frame_connect.write_config does), keeping it private.
Returns False, writing nothing, if the file no longer holds `expected`."""
fd_, tmp = tempfile.mkstemp(prefix="config.frame-control.", dir=str(path.parent))
tmp = Path(tmp)
try:
with os.fdopen(fd_, "w", encoding="utf-8") as fh:
fh.write(text)
if not frame_host.WINDOWS:
tmp.chmod(0o600)
for attempt in range(20): # Windows: a running ssh.exe can hold the file for a moment
if read_config(path) != expected:
return False
try:
os.replace(tmp, path)
return True
except PermissionError:
time.sleep(0.25)
raise OSError(f"{path} stayed locked by another program")
finally:
if tmp.exists():
tmp.unlink()
def _edit_config(path, change):
"""Apply change(lines) -> new lines or None to the file, retrying if another program
wrote it meanwhile. -> True if the file changed."""
with _config_lock, file_lock(path.with_name(LOCK_NAME)):
for _ in range(5):
text = read_config(path)
new = change(text.splitlines())
if new is None:
return False
if _write_config(path, "\n".join(new) + "\n", text):
return True
raise OSError(f"{path} kept changing while Frame Control tried to update it")
def rewrite_block(alias, path=None, hostname=None, user=None, port=None, expect=None):
"""Change HostName, User or Port inside ALIAS's managed block, leaving the rest of the
file alone. -> True if the file changed. Does nothing if there's no such block, or
if `expect` ({"hostname", "user", "port"}; None values match anything) no longer
describes the block, checked under the lock: someone else changed it meanwhile."""
def change(lines):
if expect:
block = next((b for b in parse_blocks("\n".join(lines)) if b["alias"] == alias), None)
if not block or any(v is not None and block[k] != v for k, v in expect.items()):
return None
return _rewritten(lines, alias, hostname, user, port)
return _edit_config(Path(path or ssh_config()), change)
def _rewritten(lines, alias, hostname, user, port):
begin, end = begin_mark(alias), end_mark(alias)
if begin not in lines or end not in lines:
return None
i, j = lines.index(begin), lines.index(end)
if j < i:
return None
block = lines[i:j]
want = {"hostname": ssh_host(hostname) if hostname else None, "user": user,
"port": str(port) if port else None}
out, seen = [], set()
for line in block:
f = line.split(None, 1)
key = f[0].lower() if f else ""
if key in want and want[key] is not None and key not in seen:
seen.add(key)
if key == "port" and want[key] == "22":
continue # the default; connect.sh leaves it out
out.append(f" {f[0]} {want[key]}")
else:
out.append(line)
if want["port"] and want["port"] != "22" and "port" not in seen:
at = next((n + 1 for n, line in enumerate(out) if line.split(None, 1)[:1] == ["HostName"]), 2)
out.insert(at, f" Port {want['port']}")
new = lines[:i] + out + lines[j:]
return None if new == lines else new
def remove_block(alias, path=None):
def change(lines):
begin, end = begin_mark(alias), end_mark(alias)
if begin not in lines or end not in lines or lines.index(end) < lines.index(begin):
return None
return lines[:lines.index(begin)] + lines[lines.index(end) + 1:]
return _edit_config(Path(path or ssh_config()), change)
# ---- pinned host keys -------------------------------------------------------------
def _keygen(*args):
try:
return subprocess.run(["ssh-keygen", *args], capture_output=True, stdin=subprocess.DEVNULL, text=True,
timeout=10)
except (OSError, subprocess.TimeoutExpired):
return None
def pinned(device_id):
"""Whether a key is saved for the headset. Entries are plain text (ssh gets
HashKnownHosts=no), but ask ssh-keygen too in case one was hashed."""
target = known_hosts(device_id)
try:
lines = target.read_text(encoding="utf-8").splitlines()
except (OSError, UnicodeDecodeError):
return False
name = host_key_alias(device_id)
if any(line.split(None, 1)[0].split(",").count(name) for line in lines
if line.strip() and not line.startswith("#")):
return True
r = _keygen("-F", name, "-f", str(target))
return bool(r and r.returncode == 0 and r.stdout.strip())
def seed_pin(device_id, hosts, port=22, sources=None):
"""Copy the host keys ssh already trusts for one of `hosts` into the headset's file
under its alias, so moving to per-headset pinning asks nobody to trust anything again.
-> True if a key is pinned."""
if pinned(device_id):
return True
sources = sources or [ssh_dir() / "known_hosts", ssh_dir() / "known_hosts2"]
name = host_key_alias(device_id)
for host in hosts:
wanted = host if port == 22 else f"[{host}]:{port}"
keys = []
for src in sources:
if not Path(src).is_file():
continue
r = _keygen("-F", wanted, "-f", str(src))
for line in (r.stdout if r else "").splitlines():
f = line.split()
if len(f) >= 3 and not line.startswith("#") and not f[0].startswith("@"):
keys.append(f"{name} {f[1]} {f[2]}")
if keys:
target = known_hosts(device_id)
target.parent.mkdir(**({} if frame_host.WINDOWS else {"mode": 0o700}), parents=True, exist_ok=True)
fd_, tmp = tempfile.mkstemp(prefix=".seed-", dir=str(target.parent))
with os.fdopen(fd_, "w", encoding="utf-8") as fh:
fh.write("\n".join(dict.fromkeys(keys)) + "\n")
os.replace(tmp, target) # whole file at once: ssh never sees half of it
return True
return False
def forget_pin(device_id):
"""Drop a headset's saved key, e.g. after SteamOS was reinstalled. The next connection
trusts whatever key the headset shows, as a first connection does."""
try:
known_hosts(device_id).unlink()
return True
except FileNotFoundError:
return False
# ---- address order --------------------------------------------------------------------
def order_addresses(addresses, network_id, tailscale_up):
"""The order to try a device's addresses in, each with why it's there:
known to work on this network, then mDNS, then Tailscale if it's up, then the rest
(addresses that only ever worked elsewhere last). The user's order breaks ties."""
def group(a):
nets = a.get("networks") or []
if network_id and network_id in nets:
return 0, "worked on this network before"
if a["kind"] == "mdns":
return 1, "mDNS name"
if a["kind"] == "tailscale":
return (2, "Tailscale") if tailscale_up else (5, "Tailscale isn't running")
if nets:
return 4, "worked on another network"
return 3, "not tried on this network yet"
ranked = sorted(enumerate(addresses), key=lambda p: (group(p[1])[0], p[0]))
return [(a, group(a)[1]) for _, a in ranked]
# ---- the registry ------------------------------------------------------------------------
def new_address(host, kind=None, label=""):
host = check_host(host)
return {"host": host, "kind": check_kind(kind) if kind else frame_network.guess_kind(host),
"label": check_text(label, "label"), "networks": [], "last_ok": None, "last_rtt_ms": None}
class Registry:
"""devices.json, loaded once and saved on every change. Thread-safe."""
def __init__(self, path=None, config=None):
self.path = Path(path or frame_host.data_dir("devices.json"))
self.config = Path(config) if config else None # None: ssh_config() at call time
self.lock = threading.RLock()
self.data = {"version": VERSION, "active": None, "devices": [], "networks": {}}
self.load()
# -- storage --
def load(self):
with self.lock:
try:
data = json.loads(self.path.read_text(encoding="utf-8"))
except (OSError, ValueError):
return
if isinstance(data, dict) and isinstance(data.get("devices"), list):
data.setdefault("networks", {})
data.setdefault("active", None)
data["devices"] = [d for d in data["devices"] if self._sane(d)]
self.data = data
@staticmethod
def _sane(d):
try:
check_alias(d["alias"])
d["addresses"] = [a for a in d.get("addresses") or [] if isinstance(a, dict) and HOST_RE.fullmatch(a.get("host", ""))
and a.get("kind") in KINDS]
for a in d["addresses"]:
a.setdefault("networks", [])
a.setdefault("label", "")
return NAME_RE.fullmatch(d.get("id", "")) is not None
except (KeyError, TypeError, DeviceError):
return False
def save(self):
with self.lock:
self.path.parent.mkdir(parents=True, exist_ok=True)
tmp = self.path.with_name(self.path.name + ".tmp")
tmp.write_text(json.dumps(self.data, indent=1), encoding="utf-8")
os.replace(tmp, self.path)
def snapshot(self):
with self.lock:
return copy.deepcopy(self.data)
# -- lookups --
def devices(self):
with self.lock:
return copy.deepcopy(self.data["devices"])
def _find(self, device_id):
for d in self.data["devices"]:
if d["id"] == device_id:
return d
raise DeviceError("No such headset (it may have been removed)")
def get(self, device_id):
with self.lock:
return copy.deepcopy(self._find(device_id))
def by_alias(self, alias):
with self.lock:
return next((copy.deepcopy(d) for d in self.data["devices"] if d["alias"] == alias), None)
def active(self):
with self.lock:
return self.data.get("active")
def set_active(self, device_id):
with self.lock:
self._find(device_id)
self.data["active"] = device_id
self.save()
# -- devices --
def add_device(self, alias, name=None, user=DEFAULT_USER, port=22, hosts=(), identity_files=()):
with self.lock:
check_alias(alias)
if any(d["alias"] == alias for d in self.data["devices"]):
raise DeviceError(f"There's already a headset with the alias {alias}")
ids = {d["id"] for d in self.data["devices"]}
device_id = secrets.token_hex(4)
while device_id in ids:
device_id = secrets.token_hex(4)
d = {"id": device_id, "name": check_text(name or ("Steam Frame" if alias == "frame" else alias), "name"),
"alias": alias, "user": check_user(user or DEFAULT_USER), "port": check_port(port),
"identity_files": [str(f) for f in identity_files][:8], "addresses": [], "config_host": None,
"added": time.time()}
for host in hosts:
if host and not any(a["host"] == host for a in d["addresses"]):
d["addresses"].append(new_address(host))
self.data["devices"].append(d)
if not self.data.get("active"):
self.data["active"] = device_id
self.save()
return copy.deepcopy(d)
def update_device(self, device_id, name=None, user=None, port=None):
"""-> the device after the change. The caller mirrors user and port into ~/.ssh/config."""
with self.lock:
d = self._find(device_id)
if name is not None:
d["name"] = check_text(name, "name") or d["alias"]
if user is not None:
d["user"] = check_user(user)
if port is not None:
d["port"] = check_port(port)
self.save()
return copy.deepcopy(d)
def remove_device(self, device_id):
"""Forget a headset. Its ~/.ssh/config block (if kept) isn't imported again
unless Set Up Connection changes it."""
with self.lock:
d = self._find(device_id)
self.data["devices"].remove(d)
self.data.setdefault("dismissed", {})[d["alias"]] = d.get("config_host") or ""
if self.data.get("active") == device_id:
self.data["active"] = self.data["devices"][0]["id"] if self.data["devices"] else None
self.save()
return d
# -- addresses --
def _addr(self, d, host):
for a in d["addresses"]:
if a["host"] == host:
return a
raise DeviceError(f"{host} isn't one of this headset's addresses")
def add_address(self, device_id, host, kind=None, label=""):
with self.lock:
d = self._find(device_id)
a = new_address(host, kind, label)
if any(x["host"] == a["host"] for x in d["addresses"]):
raise DeviceError(f"{a['host']} is already on the list")
if len(d["addresses"]) >= 32:
raise DeviceError("That's enough addresses for one headset")
d["addresses"].append(a)
self.save()
return copy.deepcopy(a)
def update_address(self, device_id, host, new_host=None, kind=None, label=None):
with self.lock:
d = self._find(device_id)
a = self._addr(d, host)
if new_host is not None and new_host != host:
new_host = check_host(new_host)
if any(x["host"] == new_host for x in d["addresses"]):
raise DeviceError(f"{new_host} is already on the list")
a.update(host=new_host, networks=[], last_ok=None, last_rtt_ms=None) # a new place: learn again
if kind is not None:
a["kind"] = check_kind(kind)
if label is not None:
a["label"] = check_text(label, "label")
self.save()
return copy.deepcopy(a)
def remove_address(self, device_id, host):
with self.lock:
d = self._find(device_id)
d["addresses"].remove(self._addr(d, host))
self.save()
def move_address(self, device_id, host, delta):
with self.lock:
d = self._find(device_id)
a = self._addr(d, host)
i = d["addresses"].index(a)
j = max(0, min(len(d["addresses"]) - 1, i + int(delta)))
d["addresses"].insert(j, d["addresses"].pop(i))
self.save()
def record_success(self, device_id, host, network_id, rtt_ms):
"""Learn: this address worked on this network."""
with self.lock:
try:
a = self._addr(self._find(device_id), host)
except DeviceError:
return
if network_id and network_id not in a["networks"]:
a["networks"] = (a["networks"] + [network_id])[-16:]
a["last_ok"] = time.time()
a["last_rtt_ms"] = rtt_ms
self.save()
def undismiss(self, alias):
"""Set Up Connection is about to run for this alias: import its block again."""
with self.lock:
if self.data.get("dismissed", {}).pop(alias, None) is not None:
self.save()
def set_config_host(self, device_id, host):
with self.lock:
try:
self._find(device_id)["config_host"] = host
except DeviceError:
return
self.save()
# -- networks --
def record_network(self, net):
"""Remember a network we've seen (for naming it), keeping its user-given name."""
if not net or not net.get("id"):
return
with self.lock:
known = self.data["networks"].get(net["id"]) or {"name": ""}
changed = (known.get("ssid") != (net.get("ssid") or known.get("ssid")) or
time.time() - (known.get("last_seen") or 0) > 3600 or "gateway" not in known)
known.update(ssid=net.get("ssid") or known.get("ssid"), gateway=net.get("gateway"), wifi=net.get("wifi"),
gateway_mac=net.get("gateway_mac"), last_seen=time.time())
self.data["networks"][net["id"]] = known
if changed:
self.save()
def name_network(self, network_id, name):
with self.lock:
if network_id not in self.data["networks"]:
raise DeviceError("That network hasn't been seen")
self.data["networks"][network_id]["name"] = check_text(name, "network name")
self.save()
def network_name(self, net):
"""What to call a network: the name given to it, its Wi-Fi name, or its router."""
if not net:
return "No network"
with self.lock:
known = self.data["networks"].get(net.get("id") or "") or {}
if known.get("name"):
return known["name"]
ssid = net.get("ssid") or known.get("ssid")
if ssid:
return ssid
if net.get("gateway"):
return f"{'Wi-Fi' if net.get('wifi') else 'Network'} via {net['gateway']}"
return "No network"
# -- ~/.ssh/config --
def sync_from_config(self, seed=True):
"""Import managed blocks we don't know yet, and pick up a HostName that Set Up
Connection changed since we last looked. -> True if anything changed."""
blocks = parse_blocks(read_config(self.config))
changed = False
with self.lock:
for b in blocks:
host = b["hostname"] if b["hostname"] and HOST_RE.fullmatch(b["hostname"]) else None
user = b["user"] if b["user"] and NAME_RE.fullmatch(b["user"]) else DEFAULT_USER
d = next((x for x in self.data["devices"] if x["alias"] == b["alias"]), None)
dismissed = self.data.get("dismissed", {})
if d is None and b["alias"] in dismissed:
if dismissed[b["alias"]] == (host or ""):
continue # removed on the Devices tab; unchanged since
del dismissed[b["alias"]]
if d is None:
try:
d = self._find(self.add_device(b["alias"], user=user, port=b["port"],
identity_files=b["identity_files"])["id"])
except DeviceError:
continue
if host:
d["addresses"].append(dict(new_address(host), label="From Set Up Connection"))
d["config_host"] = host
changed = True
if seed and host:
seed_pin(d["id"], [host], b["port"])
elif host and host != d.get("config_host"):
# Set Up Connection ran again and found the headset somewhere new.
d["config_host"] = host
if not any(a["host"] == host for a in d["addresses"]):
d["addresses"].insert(0, dict(new_address(host), label="From Set Up Connection"))
if seed:
seed_pin(d["id"], [host], b["port"])
changed = True
if d.get("config_login") != [user, b["port"]]:
# Set Up Connection (or an edit) changed who to log in as, or the port.
if d.get("config_login") is not None and [d["user"], d["port"]] != [user, b["port"]]:
d["user"], d["port"] = user, b["port"] if 1 <= b["port"] <= 65535 else d["port"]
d["config_login"] = [user, b["port"]]
changed = True
if d["identity_files"] != b["identity_files"] and b["identity_files"]:
d["identity_files"] = b["identity_files"][:8]
changed = True
d["managed"] = True
aliases = {b["alias"] for b in blocks}
for d in self.data["devices"]:
d["managed"] = d["alias"] in aliases
if changed:
self.save()
return changed