feat(lxc): add LXC container support for local chatmail development

Add cmdeploy "lxc-test" command to run cmdeploy against local containers,
with supplementary lxc-start, lxc-stop and lxc-status subcommands.
See doc/source/lxc.rst for full documentation including prerequisites,
DNS setup, TLS handling, DNS-free testing, and known limitations.
This commit is contained in:
holger krekel
2026-03-30 08:07:11 +02:00
committed by j4n
parent 44b1cef7d2
commit 9a03588e16
8 changed files with 1691 additions and 1 deletions

1
.gitignore vendored
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@@ -5,6 +5,7 @@ __pycache__/
*.swp
*qr-*.png
chatmail*.ini
lxconfigs/
# C extensions

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@@ -0,0 +1,475 @@
"""lxc-start/stop/status/test subcommands for testing with local containers."""
import os
import time
from ..util import get_git_hash, get_version_string, shell
from .incus import RELAY_IMAGE_ALIAS, Incus, RelayContainer
RELAY_NAMES = ("test0", "test1")
# -------------------------------------------------------------------
# lxc-start
# -------------------------------------------------------------------
def lxc_start_cmd_options(parser):
_add_name_args(
parser,
help_text="User relay name(s) to create (default: test0).",
)
parser.add_argument(
"--ipv4-only",
dest="ipv4_only",
action="store_true",
help="Create an IPv4-only container.",
)
parser.add_argument(
"--run",
action="store_true",
help="Run 'cmdeploy run' on each container after starting it.",
)
def lxc_start_cmd(args, out):
"""Create/Ensure and start LXC relay and DNS containers."""
with out.section("Preparing container setup"):
_lxc_start_cmd(args, out)
def _lxc_start_cmd(args, out):
ix = Incus(out)
sub = out.new_prefixed_out()
out.green("Ensuring base image ...")
ix.ensure_base_image()
out.green("Ensuring DNS container (ns-localchat) ...")
dns_ct = ix.get_dns_container()
dns_ct.ensure()
sub.print(f"DNS container IP: {dns_ct.ipv4}")
names = args.names if args.names else RELAY_NAMES
relays = list(ix.get_container(n) for n in names)
for ct in relays:
out.green(f"Ensuring container {ct.name!r} ({ct.domain}) ...")
ct.ensure()
ip = ct.ipv4
sub.print("Configuring container hostname ...")
ct.configure_hosts(ip)
sub.print(f"Writing {ct.ini.name} ...")
ct.write_ini(disable_ipv6=args.ipv4_only)
sub.print(f"Config: {ct.ini}")
if args.ipv4_only:
ct.disable_ipv6()
ipv6 = None
else:
output = ct.bash(
"ip -6 addr show scope global -deprecated"
" | grep -oP '(?<=inet6 )[^/]+'",
check=False,
)
ipv6 = output.strip() if output else None
sub.print(f"{_format_addrs(ip, ipv6)}")
sub.green(f"Container {ct.name!r} ready: {ct.domain} -> {ip}")
out.print()
# Reset DNS zones only for the containers we just started
started_cnames = {ct.name for ct in relays}
managed = ix.list_managed()
started = [c for c in managed if c["name"] in started_cnames]
if started:
out.print(
f"Resetting DNS zones for {len(started)} domain(s) (A + AAAA records) ..."
)
dns_ct.reset_dns_records(dns_ct.ipv4, started)
for ct in relays:
if ct.name in started_cnames:
sub.print(f"Configuring DNS in {ct.name} ...")
ct.configure_dns(dns_ct.ipv4)
# Generate the unified SSH config
out.green("Writing ssh-config ...")
ssh_cfg = ix.write_ssh_config()
sub.print(f"{ssh_cfg}")
# Verify SSH via the generated config
for ct in relays:
sub.print(f"Verifying SSH to {ct.name} via ssh-config ...")
if ct.verify_ssh(ssh_cfg):
sub.print(f"SSH OK: ssh -F lxconfigs/ssh-config {ct.domain}")
else:
sub.red(f"WARNING: SSH verification failed for {ct.name}")
# Print integration suggestions
ssh_cfg = ix.ssh_config_path
if not ix.check_ssh_include():
sub.green(
"\n(Optional) To use containers from any SSH client, add to ~/.ssh/config:"
)
sub.green(f" Include {ssh_cfg}")
# Optionally run cmdeploy run + dns on each relay
if args.run:
for ct in relays:
with out.section(f"cmdeploy run: {ct.sname} ({ct.domain})"):
ret = _run_cmdeploy("run", ct, ix, out, extra=["--skip-dns-check"])
if ret:
out.red(f"Deploy to {ct.sname} failed (exit {ret})")
return ret
with out.section("loading DNS zones"):
for ct in relays:
ret = _run_cmdeploy(
"dns", ct, ix, out,
extra=["--zonefile", str(ct.zone)],
)
if ret:
out.red(f"DNS for {ct.sname} failed (exit {ret})")
return ret
if ct.zone.exists():
dns_ct.set_dns_records(ct.zone.read_text())
out.print(f"Restarting filtermail-incoming on {ct.name}")
ct.bash("systemctl restart filtermail-incoming")
# -------------------------------------------------------------------
# lxc-stop
# -------------------------------------------------------------------
def lxc_stop_cmd_options(parser):
parser.add_argument(
"--destroy",
action="store_true",
help="Delete containers and their config files after stopping.",
)
parser.add_argument(
"--destroy-all",
dest="destroy_all",
action="store_true",
help="Like --destroy, but also remove the ns-localchat DNS container.",
)
_add_name_args(
parser,
help_text="Container name(s) to stop (default: test0 + test1).",
)
def lxc_stop_cmd(args, out):
"""Stop (and optionally destroy) local LXC relay containers."""
ix = Incus(out)
names = args.names or RELAY_NAMES
destroy = args.destroy or args.destroy_all
for ct in map(ix.get_container, names):
if destroy:
out.green(f"Destroying container {ct.name!r} ...")
ct.destroy()
else:
out.green(f"Stopping container {ct.name!r} ...")
ct.stop(force=True)
if args.destroy_all:
dns_ct = ix.get_dns_container()
out.green(f"Destroying DNS container {dns_ct.name!r} ...")
dns_ct.destroy()
ix.delete_images()
if destroy:
ix.write_ssh_config()
out.green("LXC containers destroyed.")
else:
out.green("LXC containers stopped.")
# -------------------------------------------------------------------
# lxc-test
# -------------------------------------------------------------------
def lxc_test_cmd_options(parser):
parser.add_argument(
"--one",
action="store_true",
help="Only deploy and test against test0 (skip test1).",
)
def lxc_test_cmd(args, out):
"""Run full LXC pipeline: start, deploy, DNS, zone files, and tests.
All commands run directly on the host using
``--ssh-config lxconfigs/ssh-config`` for SSH access.
"""
ix = Incus(out)
t_total = time.time()
relay_names = list(RELAY_NAMES)
if args.one:
relay_names = relay_names[:1]
local_hash = get_git_hash()
# Per-relay: start, deploy, then snapshot the first relay as a
# reusable image so the second relay launches pre-deployed.
ipv4_only_flags = {RELAY_NAMES[0]: False, RELAY_NAMES[1]: True}
for ct in map(ix.get_container, relay_names):
name = ct.sname
ipv4_only = ipv4_only_flags.get(name, False)
v_flag = " -" + "v" * out.verbosity if out.verbosity > 0 else ""
start_cmd = f"cmdeploy lxc-start{v_flag} {name}"
if ipv4_only:
start_cmd += " --ipv4-only"
with out.section(f"cmdeploy lxc-start: {name}"):
ret = out.shell(start_cmd, cwd=str(ix.project_root))
if ret:
return ret
status = _deploy_status(ct, local_hash, ix)
with out.section(f"cmdeploy run: {name}"):
if "IN-SYNC" in status:
out.print(f"{name} is {status}, skipping")
else:
ret = _run_cmdeploy("run", ct, ix, out, extra=["--skip-dns-check"])
if ret:
out.red(f"Deploy to {name} failed (exit {ret})")
return ret
# Snapshot the first relay so subsequent ones launch pre-deployed
if not ix.find_image([RELAY_IMAGE_ALIAS]):
with out.section("lxc-test: caching relay image"):
ct.publish_as_relay_image()
for ct in map(ix.get_container, relay_names):
with out.section(f"cmdeploy dns: {ct.sname} ({ct.domain})"):
ret = _run_cmdeploy("dns", ct, ix, out, extra=["--zonefile", str(ct.zone)])
if ret:
out.red(f"DNS for {ct.sname} failed (exit {ret})")
return ret
with out.section(f"lxc-test: loading DNS zones {' & '.join(relay_names)}"):
dns_ct = ix.get_dns_container()
for ct in map(ix.get_container, relay_names):
if ct.zone.exists():
zone_data = ct.zone.read_text()
out.print(f"Loading {ct.zone} into PowerDNS ...")
dns_ct.set_dns_records(zone_data)
# Restart filtermail so its in-process DNS cache
# does not hold stale negative DKIM responses
# from before the zones were loaded.
for ct in map(ix.get_container, relay_names):
out.print(f"Restarting filtermail-incoming on {ct.name} ...")
ct.bash("systemctl restart filtermail-incoming")
with out.section("cmdeploy test"):
first = ix.get_container(relay_names[0])
env = None
if len(relay_names) > 1:
env = os.environ.copy()
env["CHATMAIL_DOMAIN2"] = ix.get_container(relay_names[1]).domain
ret = _run_cmdeploy("test", first, ix, out, **({"env": env} if env else {}))
if ret:
out.red(f"Tests failed (exit {ret})")
return ret
elapsed = time.time() - t_total
out.section_line(f"lxc-test complete ({elapsed:.1f}s)")
if out.section_timings:
out.print("Section timings:")
for name, secs in out.section_timings:
out.print(f" {name:.<50s} {secs:5.1f}s")
out.print(f" {'total':.<50s} {elapsed:5.1f}s")
out.section_timings.clear()
return 0
# -------------------------------------------------------------------
# lxc-status
# -------------------------------------------------------------------
def lxc_status_cmd_options(parser):
pass
def lxc_status_cmd(args, out):
"""Show status of local LXC chatmail containers."""
ix = Incus(out)
containers = ix.list_managed()
if not containers:
out.red("No LXC containers found. Run 'cmdeploy lxc-start' first.")
return 1
local_hash = get_git_hash()
# Get storage pool path for display
storage_path = None
data = ix.run_json(["storage", "show", "default"], check=False)
if data:
storage_path = data.get("config", {}).get("source")
msg = "Container status"
if storage_path:
msg += f": {storage_path}"
out.section_line(msg)
dns_ip = None
for c in containers:
_print_container_status(out, c, ix, local_hash)
if c["name"] == ix.get_dns_container().name:
dns_ip = c["ip"]
out.section_line("Host ssh and DNS configuration")
_print_ssh_status(out, ix)
_print_dns_forwarding_status(out, dns_ip)
return 0
def _print_container_status(out, c, ix, local_hash):
"""Print name/status, domain/IPs, and RAM for one container."""
cname = c["name"]
is_running = c.get("status") == "Running"
ct = ix.get_container(cname)
# First line: name + running/STOPPED + deploy status
if not is_running:
tag = "STOPPED"
elif not isinstance(ct, RelayContainer):
tag = "running"
else:
tag = f"running {_deploy_status(ct, local_hash, ix)}"
out.print(f"{cname:20s} {tag}")
# Second line: domain, IPv4, IPv6
domain = c.get("domain", "")
ip = c.get("ip") or "?"
ipv6 = c.get("ipv6")
out.print(f"{domain:20s} {_format_addrs(ip, ipv6)}")
# Third line: RAM (RSS), config
detail_out = out.new_prefixed_out(" " * 21)
try:
used, total = ct.rss_mib()
except Exception:
ram_str = "RSS ?"
else:
ram_str = f"RSS {used}/{total} MiB ({used * 100 // total}%)"
if isinstance(ct, RelayContainer):
detail = f"{ram_str}, config: {os.path.relpath(ct.ini)}"
else:
detail = ram_str
detail_out.print(detail)
out.print()
def _print_ssh_status(out, ix):
"""Print SSH integration status."""
ssh_cfg = ix.ssh_config_path
if ix.check_ssh_include():
out.green("SSH: ~/.ssh/config includes lxconfigs/ssh-config ✓")
else:
out.red("SSH: ~/.ssh/config does NOT include lxconfigs/ssh-config")
sub = out.new_prefixed_out()
sub.print("Add to ~/.ssh/config:")
sub.print(f" Include {ssh_cfg}")
def _print_dns_forwarding_status(out, dns_ip):
"""Print host DNS forwarding status for .localchat."""
sub = out.new_prefixed_out()
if not dns_ip:
out.red("DNS: ns-localchat container not found")
return
try:
rv = shell("resolvectl status incusbr0")
dns_ok = dns_ip in rv.stdout and "localchat" in rv.stdout
except Exception:
dns_ok = None
if dns_ok is True:
out.green(f"DNS: .localchat forwarding to {dns_ip}")
elif dns_ok is False:
out.red("DNS: .localchat forwarding NOT configured")
sub.print("Run:")
sub.print(f" sudo resolvectl dns incusbr0 {dns_ip}")
sub.print(" sudo resolvectl domain incusbr0 ~localchat")
else:
sub.print("DNS: .localchat forwarding status UNKNOWN")
# -------------------------------------------------------------------
# Internal helpers
# -------------------------------------------------------------------
def _format_addrs(ip, ipv6=None):
parts = [f"IPv4 {ip}"]
if ipv6:
parts.append(f"IPv6 {ipv6}")
return ", ".join(parts)
def _deploy_status(ct, local_hash, ix):
"""Return a human-readable deploy status string.
Compares the full deployed version (hash + diff) against
the local state built by :func:`~cmdeploy.util.get_version_string`.
"""
deployed = ct.deployed_version()
if deployed is None:
return "NOT DEPLOYED"
# A container launched from the relay image has the same
# git hash but a different domain — always redeploy.
deployed_domain = ct.deployed_domain()
if deployed_domain and deployed_domain != ct.domain:
return f"DOMAIN-MISMATCH (deployed: {deployed_domain})"
deployed_lines = deployed.splitlines()
deployed_hash = deployed_lines[0] if deployed_lines else ""
short = deployed_hash[:12]
if not local_hash:
return f"UNKNOWN (deployed: {short})"
local_short = local_hash[:12]
if deployed_hash != local_hash:
return f"STALE (deployed: {short}, local: {local_short})"
# Hash matches — check for uncommitted diffs
local_version = get_version_string()
if deployed != local_version:
return f"DIRTY ({local_short}, undeployed changes)"
return f"IN-SYNC ({short})"
def _add_name_args(parser, help_text):
parser.add_argument("names", nargs="*", metavar="NAME", help=help_text)
def _run_cmdeploy(subcmd, ct, ix, out, extra=None, **kwargs):
"""Run ``cmdeploy <subcmd>`` with standard --config/--ssh flags.
*ct* is a Container (uses ``ct.ini`` and ``ct.domain``).
Returns the subprocess exit code.
"""
extra_str = " ".join(extra) if extra else ""
v_flag = " -" + "v" * out.verbosity if out.verbosity > 0 else ""
cmd = f"""
cmdeploy {subcmd}{v_flag}
--config {ct.ini}
--ssh-config {ix.ssh_config_path}
--ssh-host {ct.domain}
{extra_str}
"""
if "cwd" not in kwargs:
kwargs["cwd"] = str(ix.project_root)
return out.shell(cmd, **kwargs)

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"""Core Incus operations for local chatmail LXC containers."""
import json
import subprocess
import textwrap
import time
from pathlib import Path
from ..util import shell
LABEL_KEY = "user.localchat-managed"
SSH_KEY_NAME = "id_localchat"
DOMAIN_SUFFIX = ".localchat"
UPSTREAM_IMAGE = "images:debian/12"
BASE_IMAGE_ALIAS = "localchat-base"
BASE_SETUP_NAME = "localchat-base-setup"
RELAY_IMAGE_ALIAS = "localchat-relay"
DNS_CONTAINER_NAME = "ns-localchat"
DNS_DOMAIN = "ns.localchat"
class DNSConfigurationError(Exception):
"""Raised when the DNS container is not reachable or not answering."""
def _extract_ip(net_data, family="inet"):
"""Extract the first global-scope IP of *family* from network state data.
*net_data* is the ``state.network`` dict from ``incus list --format=json``.
*family* is ``"inet"`` for IPv4 or ``"inet6"`` for IPv6.
Returns the address string, or None.
"""
for iface_name, iface in net_data.items():
if iface_name == "lo":
continue
for addr in iface.get("addresses", []):
if addr["family"] == family and addr["scope"] == "global":
return addr["address"]
return None
class Incus:
"""Gateway for all Incus container operations.
Instantiated once per CLI command and passed around so that
all modules share a single entry point for Incus interactions.
"""
def __init__(self, out):
self.out = out
self.project_root = Path(__file__).resolve().parent.parent.parent.parent.parent
self.lxconfigs_dir = self.project_root / "lxconfigs"
self.lxconfigs_dir.mkdir(exist_ok=True)
self.ssh_key_path = self.lxconfigs_dir / SSH_KEY_NAME
if not self.ssh_key_path.exists():
shell(
f"ssh-keygen -t ed25519 -f {self.ssh_key_path} -N '' -C localchat",
check=True,
)
self.ssh_config_path = self.lxconfigs_dir / "ssh-config"
def write_ssh_config(self):
"""Write ``lxconfigs/ssh-config`` mapping all containers to their IPs.
Each Host block maps the container name, the domain name, and the
short relay name (e.g. ``_test0``) to the container's IP, using the
shared localchat SSH key. Returns the path to the file.
"""
containers = self.list_managed()
key_path = self.ssh_key_path
lines = ["# Auto-generated by cmdeploy lxc-start — do not edit\n"]
for c in containers:
hosts = [c["name"]]
domain = c.get("domain", "")
if domain and domain != c["name"]:
hosts.append(domain)
short = domain.split(".")[0]
if short and short not in hosts:
hosts.append(short)
lines.append(f"\nHost {' '.join(hosts)}\n")
lines.append(f" Hostname {c['ip']}\n")
lines.append(" User root\n")
lines.append(f" IdentityFile {key_path}\n")
lines.append(" IdentitiesOnly yes\n")
lines.append(" StrictHostKeyChecking accept-new\n")
lines.append(" UserKnownHostsFile /dev/null\n")
lines.append(" LogLevel ERROR\n")
path = self.ssh_config_path
path.write_text("".join(lines))
return path
def check_ssh_include(self):
"""Check if the user's ~/.ssh/config already includes our ssh-config."""
user_ssh_config = Path.home() / ".ssh" / "config"
if not user_ssh_config.exists():
return False
lines = user_ssh_config.read_text().splitlines()
target = f"include {self.ssh_config_path}".lower()
return any(line.strip().lower() == target for line in lines)
def get_host_nameservers(self):
"""Return upstream nameservers found on the host."""
ns = []
for path in ["/run/systemd/resolve/resolv.conf", "/etc/resolv.conf"]:
p = Path(path)
if p.exists():
for line in p.read_text().splitlines():
if line.strip().startswith("nameserver "):
addr = line.split()[1]
if addr not in ("127.0.0.1", "127.0.0.53", "::1"):
if addr not in ns:
ns.append(addr)
if ns:
break
return ns
def run(self, args, check=True, capture=True, input=None):
"""Run an incus command.
When *capture* is True and *verbosity* >= 1, output is streamed
to the terminal line-by-line while also being captured for
later return via result.stdout.
"""
cmd = ["incus", "--quiet"] + list(args)
sub = self.out.new_prefixed_out(" ")
if not capture:
# Simple case: let subprocess handle streams (no capture)
if self.out.verbosity >= 1:
sub.print(f"$ {' '.join(cmd)}")
return subprocess.run(
cmd, text=True, input=input, check=check, stdout=None, stderr=None
)
# Capture case: we may need to stream while capturing
if sub.verbosity >= 1:
cmd_lines = " ".join(cmd).splitlines()
sub.print(f"$ {cmd_lines.pop(0)}")
if sub.verbosity >= 2:
for line in cmd_lines:
sub.print(f" {line}")
proc = subprocess.Popen(
cmd,
text=True,
stdin=subprocess.PIPE if input else subprocess.DEVNULL,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE,
)
stdout_lines = []
if input:
proc.stdin.write(input)
proc.stdin.close()
for line in proc.stdout:
stdout_lines.append(line)
if sub.verbosity >= 2:
sub.print(f" > {line.rstrip()}")
stderr = proc.stderr.read()
ret = proc.wait()
stdout = "".join(stdout_lines)
if check and ret != 0:
full_output = stdout + stderr
for line in full_output.splitlines():
if sub.verbosity < 1: # and we haven't printed it yet
sub.red(line)
raise subprocess.CalledProcessError(ret, cmd, output=stdout, stderr=stderr)
return subprocess.CompletedProcess(cmd, ret, stdout=stdout, stderr=stderr)
def run_json(self, args, check=True):
"""Run an incus command with ``--format=json``.
Returns the parsed JSON on success.
When *check* is True raises ``subprocess.CalledProcessError``
on non-zero exit; when False returns *None* instead.
"""
result = self.run(
list(args) + ["--format=json"],
check=check,
)
if result.returncode != 0:
return None
return json.loads(result.stdout)
def run_output(self, args, check=True):
"""Run an incus command and return its stripped stdout.
When *check* is False, returns *None* on non-zero exit
instead of raising.
"""
result = self.run(args, check=check)
if result.returncode != 0:
return None
return result.stdout.strip()
def find_image(self, aliases):
"""Return the first alias from *aliases* that exists, else None."""
images = self.run_json(["image", "list"], check=False) or []
existing = {a.get("name") for img in images for a in img.get("aliases", [])}
for alias in aliases:
if alias in existing:
return alias
return None
def delete_images(self):
"""Delete the cached base and relay images."""
for alias in (RELAY_IMAGE_ALIAS, BASE_IMAGE_ALIAS):
self.run(["image", "delete", alias], check=False) # ok if absent
def list_managed(self):
"""Return list of dicts with name, ip, ipv6, domain, status, memory_usage."""
containers = []
for ct in self.run_json(["list"]):
config = ct.get("config", {})
if config.get(LABEL_KEY) != "true":
continue
name = ct["name"]
state = ct.get("state", {})
net = state.get("network") or {}
containers.append(
{
"name": name,
"ip": _extract_ip(net, "inet"),
"ipv6": _extract_ip(net, "inet6"),
"domain": config.get(
"user.localchat-domain", f"{name}{DOMAIN_SUFFIX}"
),
"status": ct.get("status", "Unknown"),
"memory_usage": state.get("memory", {}).get("usage", 0),
}
)
return containers
def ensure_base_image(self):
"""Build and cache a base image with openssh and the SSH key.
The image is published as a local incus image with alias
'localchat-base'. Subsequent container launches use this
image instead of the upstream Debian 12, skipping the
slow apt-get install step.
Returns the image alias.
"""
if self.find_image([BASE_IMAGE_ALIAS]):
self.out.print(f" Base image '{BASE_IMAGE_ALIAS}' already cached.")
return BASE_IMAGE_ALIAS
self.out.print(" Building base image (one-time setup) ...")
self.run(["delete", BASE_SETUP_NAME, "--force"], check=False)
self.run(["image", "delete", BASE_IMAGE_ALIAS], check=False)
self.run(["launch", UPSTREAM_IMAGE, BASE_SETUP_NAME])
ct = Container(self, BASE_SETUP_NAME)
ct.wait_ready()
key_path = self.ssh_key_path
pub_key = key_path.with_suffix(".pub").read_text().strip()
host_ns = self.get_host_nameservers()
ns_lines = "\n".join(f"nameserver {n}" for n in host_ns)
ct.bash(f"""
printf '{ns_lines}\n' > /etc/resolv.conf
apt-get -o DPkg::Lock::Timeout=60 update
DEBIAN_FRONTEND=noninteractive apt-get install -y openssh-server python3
systemctl enable ssh
apt-get clean
mkdir -p /root/.ssh
chmod 700 /root/.ssh
echo '{pub_key}' > /root/.ssh/authorized_keys
chmod 600 /root/.ssh/authorized_keys
""")
self.run(["stop", BASE_SETUP_NAME])
self.run(["publish", BASE_SETUP_NAME, f"--alias={BASE_IMAGE_ALIAS}"])
self.run(["delete", BASE_SETUP_NAME, "--force"])
self.out.print(f" Base image '{BASE_IMAGE_ALIAS}' ready.")
return BASE_IMAGE_ALIAS
def get_container(self, name):
"""Return a container handle for the given name.
Accepts both short relay names (``test0``) and full Incus
container names (``test0-localchat``). Returns
``DNSContainer`` for the DNS container and
``RelayContainer`` for everything else.
"""
if name == DNS_CONTAINER_NAME:
return DNSContainer(self)
return RelayContainer(self, name.removesuffix("-localchat"))
def get_dns_container(self):
"""Return a DNSContainer handle."""
return DNSContainer(self)
class Container:
"""The base container handle wraps all interactions with incus."""
def __init__(self, incus, name, domain=None):
self.incus = incus
self.out = incus.out
self.name = name
self.domain = domain or f"{name}{DOMAIN_SUFFIX}"
self.ipv4 = None
self.ipv6 = None
def bash(self, script, check=True):
"""Returns stdout from executing ``bash -ec <script>`` inside this container.
*script* is dedented and stripped so callers can use triple-quoted strings.
When *check* is False, returns *None* on non-zero exit instead of raising.
"""
script = textwrap.dedent(script).strip()
cmd = ["exec", self.name, "--", "bash", "-ec", script]
return self.incus.run_output(cmd, check=check)
def run_cmd(self, *args, check=True):
"""Return stdout from running a command directly in the container (no shell).
When *check* is False, returns *None* on non-zero exit instead of raising.
"""
return self.incus.run_output(
["exec", self.name, "--", *args],
check=check,
)
def start(self):
self.incus.run(["start", self.name])
def stop(self, force=False):
cmd = ["stop", self.name]
if force:
cmd.append("--force")
self.incus.run(cmd, check=False)
def launch(self):
"""Launch from the best available image, return the alias used."""
image = self.incus.find_image([RELAY_IMAGE_ALIAS, BASE_IMAGE_ALIAS])
if not image:
raise RuntimeError(
f"No base image '{BASE_IMAGE_ALIAS}' found. "
"Call ensure_base_image() before launching containers."
)
self.out.print(f" Launching from '{image}' image ...")
cfg = []
cfg += ("-c", f"{LABEL_KEY}=true")
cfg += ("-c", f"user.localchat-domain={self.domain}")
self.incus.run(["launch", image, self.name, *cfg])
return image
def ensure(self):
"""Create/start this container from the cached base image.
On first call, builds the base image (~30s).
Subsequent containers launch in ~2s from the cached image.
Returns ``self`` for chaining.
"""
data = self.incus.run_json(["list", self.name], check=False) or []
existing = [c for c in data if c["name"] == self.name]
if existing:
if existing[0]["status"] != "Running":
self.start()
else:
self.launch()
self.wait_ready()
return self
def destroy(self):
"""Stop, delete, and clean up config files."""
self.stop(force=True)
self.incus.run(["delete", self.name, "--force"], check=False)
def push_file_content(self, dest_path, content):
"""Write *content* to *dest_path* inside the container.
*content* is dedented and stripped so callers can use
indented triple-quoted strings.
"""
content = textwrap.dedent(content).strip() + "\n"
self.incus.run(
["file", "push", "-", f"{self.name}{dest_path}"],
input=content,
)
self.bash(f"chmod 644 {dest_path}")
def wait_ready(self, timeout=60):
"""Wait until the container is running with an IPv4 address.
Sets ``self.ipv4`` and ``self.ipv6`` (may be *None*),
or raises ``TimeoutError``.
"""
deadline = time.time() + timeout
while time.time() < deadline:
data = self.incus.run_json(
["list", self.name],
check=False,
)
if data and data[0].get("status") == "Running":
net = data[0].get("state", {}).get("network", {})
self.ipv4 = _extract_ip(net, "inet")
self.ipv6 = _extract_ip(net, "inet6")
if self.ipv4:
return
time.sleep(1)
raise TimeoutError(
f"Container {self.name!r} did not become ready within {timeout}s"
)
def rss_mib(self):
"""Return ``(used, total)`` memory from container (or None if unobtainable)."""
output = self.bash("free -m", check=False)
if output:
for line in output.splitlines():
if line.startswith("Mem:"):
parts = line.split()
return int(parts[2]), int(parts[1])
class RelayContainer(Container):
"""Container handle for a chatmail relay.
Accepts the short relay name (e.g. ``test0``) and derives
the Incus container name and mail domain automatically.
"""
def __init__(self, incus, name):
super().__init__(
incus,
f"{name}-localchat",
domain=f"_{name}{DOMAIN_SUFFIX}",
)
self.sname = name
self.ini = incus.lxconfigs_dir / f"chatmail-{name}.ini"
self.zone = incus.lxconfigs_dir / f"{name}.zone"
def launch(self):
"""Launch (from a potentially cached image) and clear inherited chatmail-version."""
image = super().launch()
self.bash("rm -f /etc/chatmail-version")
return image
def destroy(self):
"""Stop, delete, and clean up config files."""
super().destroy()
if self.ini.exists():
self.ini.unlink()
def disable_ipv6(self):
"""Disable IPv6 inside the container via sysctl."""
# incus provides net.* virtualization for LXC containers so that
# these sysctls only affect the container's network namespace.
self.bash("""
sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1
""")
self.push_file_content(
"/etc/sysctl.d/99-disable-ipv6.conf",
"""
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
""",
)
def configure_hosts(self, ip):
"""Set hostname and /etc/hosts inside the container."""
self.bash(f"""
echo '{self.name}' > /etc/hostname
hostname {self.name}
sed -i '/ {self.domain}$/d' /etc/hosts
echo '{ip} {self.name} {self.domain}' >> /etc/hosts
""")
def publish_as_relay_image(self):
"""Publish this container as a reusable relay image.
Stops the container, 'publishes' it as 'localchat-relay', then restarts it.
"""
if self.incus.find_image([RELAY_IMAGE_ALIAS]):
return
self.out.print(
f" Locally caching {self.name!r} as '{RELAY_IMAGE_ALIAS}' image ..."
)
self.incus.run(
["publish", self.name, f"--alias={RELAY_IMAGE_ALIAS}", "--force"]
)
self.wait_ready()
self.out.print(f" Relay image '{RELAY_IMAGE_ALIAS}' ready.")
def deployed_version(self):
"""Read /etc/chatmail-version, or None if absent."""
return self.bash("cat /etc/chatmail-version", check=False)
def deployed_domain(self):
"""Read the domain deployed on the container (postfix myhostname)."""
return self.bash(
"postconf -h myhostname 2>/dev/null",
check=False,
)
def verify_ssh(self, ssh_config):
"""Verify SSH connectivity to this container."""
cmd = f"ssh -F {ssh_config} -o ConnectTimeout=60 root@{self.domain} hostname"
return shell(cmd, timeout=60).returncode == 0
def configure_dns(self, dns_ip):
"""Point this container's resolver at *dns_ip* and verify DNS is reachable."""
self.bash(f"""
systemctl disable --now systemd-resolved 2>/dev/null || true
rm -f /etc/resolv.conf
printf 'nameserver {dns_ip}\\n' >/etc/resolv.conf
mkdir -p /etc/unbound/unbound.conf.d
""")
self.push_file_content(
"/etc/unbound/unbound.conf.d/localchat-forward.conf",
f"""
server:
domain-insecure: "localchat"
forward-zone:
name: "localchat"
forward-addr: {dns_ip}
""",
)
self.bash("systemctl restart unbound 2>/dev/null || true")
self._wait_dns_reachable(dns_ip)
def _wait_dns_reachable(self, dns_ip, timeout=10):
"""Poll until *dns_ip* answers a DNS query from this container."""
if self.bash("which dig", check=False) is None:
self.bash(
"DEBIAN_FRONTEND=noninteractive "
"apt-get install -y dnsutils 2>/dev/null || true"
)
deadline = time.time() + timeout
while time.time() < deadline:
result = self.bash(
f"dig @{dns_ip} . SOA +short +time=1 +tries=1",
check=False,
)
if result and result.strip():
return
time.sleep(0.5)
raise DNSConfigurationError(
f"DNS at {dns_ip} not reachable from {self.name} after {timeout}s"
)
def write_ini(self, disable_ipv6=False):
"""Generate a chatmail.ini config file in lxconfigs/."""
from chatmaild.config import write_initial_config
overrides = {
"max_user_send_per_minute": 600,
"max_user_send_burst_size": 100,
"mtail_address": "127.0.0.1",
}
if disable_ipv6:
overrides["disable_ipv6"] = "True"
write_initial_config(self.ini, self.domain, overrides)
return self.ini
class DNSContainer(Container):
"""Container handle for the PowerDNS name server.
Manages the authoritative and recursive DNS services required for
name resolution in the local testing environment.
"""
def __init__(self, incus):
super().__init__(incus, DNS_CONTAINER_NAME, domain=DNS_DOMAIN)
def pdnsutil(self, *args, check=True):
"""Run ``pdnsutil <args>`` inside the DNS container."""
return self.run_cmd("pdnsutil", *args, check=check)
def replace_rrset(self, zone, name, rtype, ttl, rdata):
"""Shortcut for ``pdnsutil replace-rrset``."""
self.pdnsutil("replace-rrset", zone, name, rtype, ttl, rdata)
def restart_services(self):
"""Restart pdns and pdns-recursor, then wait until DNS is answering."""
self.bash("""
systemctl restart pdns
systemctl restart pdns-recursor || true
""")
self._wait_dns_ready()
def _wait_dns_ready(self, timeout=60):
"""Poll until the recursor answers a query on port 53."""
deadline = time.time() + timeout
while time.time() < deadline:
result = self.bash(
"dig @127.0.0.1 . SOA +short +time=1 +tries=1",
check=False,
)
if result and result.strip():
return
time.sleep(0.5)
raise DNSConfigurationError(f"DNS recursor not answering after {timeout}s")
def ensure(self):
"""Create the DNS container with PowerDNS if needed.
Calls ``super().ensure()`` to create/start the container
and set up SSH, then installs PowerDNS and configures
the Incus bridge to use this container as DNS.
"""
super().ensure()
self._install_powerdns()
self.incus.run(
["network", "set", "incusbr0", "dns.mode=none"],
check=False,
)
self.incus.run(
["network", "set", "incusbr0", f"raw.dnsmasq=dhcp-option=6,{self.ipv4}"],
check=False,
)
def destroy(self):
"""Stop, delete, and reset bridge DNS config."""
super().destroy()
self.incus.run(["network", "unset", "incusbr0", "dns.mode"], check=False)
self.incus.run(["network", "unset", "incusbr0", "raw.dnsmasq"], check=False)
def _install_powerdns(self):
"""Install and configure PowerDNS if not already present."""
if self.run_cmd("which", "pdns_server", check=False) is not None:
return
host_ns = self.incus.get_host_nameservers()
ns_lines = "\n".join(f"nameserver {n}" for n in host_ns)
self.bash(f"""
systemctl disable --now systemd-resolved 2>/dev/null || true
rm -f /etc/resolv.conf
printf '{ns_lines}\n' > /etc/resolv.conf
# Block automatic service startup during package installation
printf '#!/bin/sh\\nexit 101\\n' > /usr/sbin/policy-rc.d
chmod +x /usr/sbin/policy-rc.d
apt-get -o DPkg::Lock::Timeout=60 update
DEBIAN_FRONTEND=noninteractive apt-get install -y \
pdns-server pdns-backend-sqlite3 sqlite3 pdns-recursor dnsutils
# Remove the startup block
rm /usr/sbin/policy-rc.d
systemctl stop pdns pdns-recursor || true
mkdir -p /var/lib/powerdns
sqlite3 /var/lib/powerdns/pdns.sqlite3 \
</usr/share/doc/pdns-backend-sqlite3/schema.sqlite3.sql
chown -R pdns:pdns /var/lib/powerdns
""")
self.push_file_content(
"/etc/powerdns/pdns.conf",
"""
launch=gsqlite3
gsqlite3-database=/var/lib/powerdns/pdns.sqlite3
local-address=127.0.0.1
local-port=5353
""",
)
self.push_file_content(
"/etc/powerdns/recursor.conf",
"""
local-address=0.0.0.0
local-port=53
forward-zones=localchat=127.0.0.1:5353
allow-from=0.0.0.0/0
dont-query=
dnssec=off
""",
)
self.bash("""
systemctl start pdns
systemctl start pdns-recursor
echo 'nameserver 127.0.0.1' > /etc/resolv.conf
""")
self._wait_dns_ready()
def reset_dns_records(self, dns_ip, domains):
"""Create DNS zones with initial A records via pdnsutil.
Only sets SOA, NS, and A records as the minimal set
needed for SSH connectivity. Full records (MX, TXT, SRV,
CNAME, DKIM) are added later by ``cmdeploy dns``.
Args:
dns_ip: IP of the DNS container
domains: list of dicts with 'name', 'domain', 'ip'
"""
for d in domains:
domain = d["domain"]
ip = d["ip"]
self.out.print(f" {domain} -> {ip}")
# Delete and recreate zone fresh (removes stale records)
self.pdnsutil("delete-zone", domain, check=False)
self.pdnsutil("create-zone", domain, f"ns.{domain}")
serial = str(int(time.time()))
soa = f"ns.{domain} hostmaster.{domain} {serial} 3600 900 604800 300"
self.replace_rrset(domain, ".", "SOA", "3600", soa)
self.replace_rrset(domain, ".", "NS", "3600", f"ns.{domain}.")
self.replace_rrset(domain, ".", "A", "3600", ip)
self.replace_rrset(domain, "ns", "A", "3600", dns_ip)
# AAAA (domain -> container IPv6, if available)
ipv6 = d.get("ipv6")
if ipv6:
self.replace_rrset(domain, ".", "AAAA", "3600", ipv6)
self.out.print(f" zone reset: SOA, NS, A, AAAA ({ip}, {ipv6})")
else:
# Remove any stale AAAA record
self.pdnsutil("delete-rrset", domain, ".", "AAAA", check=False)
self.out.print(f" zone reset: SOA, NS, A ({ip}, IPv4-only)")
self.restart_services()
def set_dns_records(self, text):
"""Add or overwrite DNS records from standard BIND format.
Uses ``cmdeploy.dns.parse_zone_records`` to parse.
Zones are created automatically from the record names.
"""
from ..dns import parse_zone_records
zones_seen = set()
for name, ttl, rtype, rdata in parse_zone_records(text):
# Derive zone from name: find top-level .localchat domain
name_parts = name.split(".")
zone = name # fallback
for i in range(len(name_parts) - 1):
if name_parts[i + 1 :] == ["localchat"]:
zone = ".".join(name_parts[i:])
break
# Create zone if first time seeing it
if zone not in zones_seen:
self.pdnsutil(
"create-zone",
zone,
f"ns.{zone}",
check=False,
)
zones_seen.add(zone)
# Figure out the record name relative to zone
if name == zone:
relative = "."
elif name.endswith(f".{zone}"):
relative = name[: -(len(zone) + 1)]
else:
relative = name
self.replace_rrset(zone, relative, rtype, ttl, rdata)
if zones_seen:
self.restart_services()

View File

@@ -0,0 +1,174 @@
"""Tests for cmdeploy lxc-* subcommands."""
import shutil
import subprocess
import sys
import pytest
from cmdeploy.lxc import cli
from cmdeploy.lxc.incus import Incus
from cmdeploy.util import Out
pytestmark = pytest.mark.skipif(
not shutil.which("incus"),
reason="incus not installed",
)
# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------
@pytest.fixture
def ix():
out = Out()
return Incus(out)
@pytest.fixture(scope="session")
def lxc_setup():
out = Out()
ix = Incus(out)
ix.get_dns_container().ensure()
return ix.list_managed()
@pytest.fixture(scope="session")
def relay_container(lxc_setup):
test_names = {f"{n}-localchat" for n in cli.RELAY_NAMES}
relays = [c for c in lxc_setup if c["name"] in test_names and c.get("ip")]
if not relays:
pytest.skip("no test relay containers running")
return relays[0]
@pytest.fixture
def cmdeploy():
def run(*args):
return subprocess.run(
[sys.executable, "-m", "cmdeploy.cmdeploy", *args],
capture_output=True,
text=True,
check=False,
)
return run
# ---------------------------------------------------------------------------
# Tests
# ---------------------------------------------------------------------------
@pytest.mark.parametrize(
"subcmd, expected, absent",
[
(None, ["lxc-start", "lxc-stop", "lxc-test", "lxc-status"], ["lxc-destroy"]),
("lxc-start", ["--ipv4-only", "--run"], ["--config"]),
("lxc-stop", ["--destroy", "--destroy-all"], ["--config"]),
("lxc-test", ["--one"], ["--config"]),
("lxc-status", [], ["--config"]),
("run", ["--ssh-config"], ["--lxc"]),
("dns", ["--ssh-config"], []),
("test", ["--ssh-config"], []),
("status", ["--ssh-config"], []),
],
)
def test_help_options(cmdeploy, subcmd, expected, absent):
args = [subcmd, "--help"] if subcmd else ["--help"]
result = cmdeploy(*args)
output = result.stdout + result.stderr
assert result.returncode == 0
for flag in expected:
assert flag in output
for flag in absent:
assert flag not in output
class TestSSHConfig:
def test_lxconfigs(self, ix, lxc_setup):
d = ix.lxconfigs_dir
assert d.name == "lxconfigs"
assert d.exists()
path = ix.ssh_config_path
assert path.name == "ssh-config"
assert path.parent.name == "lxconfigs"
def test_write_ssh_config(self, ix, lxc_setup):
path = ix.write_ssh_config()
assert path.exists()
text = path.read_text()
for c in lxc_setup:
if c.get("ip"):
assert c["name"] in text
assert f"Hostname {c['ip']}" in text
assert "User root" in text
assert "IdentityFile" in text
assert "StrictHostKeyChecking accept-new" in text
def test_dns(ix, relay_container):
def dig(qname, qtype):
ct = ix.get_dns_container()
return ct.bash(f"dig @127.0.0.1 {qname} {qtype} +short").strip()
domain = relay_container["domain"]
assert dig(domain, "A") == relay_container["ip"]
assert domain in dig(domain, "MX")
assert "587" in dig(f"_submission._tcp.{domain}", "SRV")
class TestLxcStatus:
def test_cli_lxc_status_help(self, cmdeploy):
result = cmdeploy("lxc-status", "--help")
assert result.returncode == 0
assert "status" in result.stdout.lower()
def test_shows_containers(self, lxc_setup, capsys):
class QuietOut(Out):
def red(self, msg, **kw):
pass
def green(self, msg, **kw):
pass
ret = cli.lxc_status_cmd(None, QuietOut())
assert ret == 0
captured = capsys.readouterr().out
assert "ns-localchat" in captured
assert "running" in captured
def test_deploy_freshness(self, ix, monkeypatch):
ct = ix.get_container("x")
monkeypatch.setattr(
"cmdeploy.lxc.incus.RelayContainer.deployed_version",
lambda _self: "abc123def456",
)
monkeypatch.setattr(
"cmdeploy.lxc.incus.RelayContainer.deployed_domain",
lambda _self: ct.domain,
)
monkeypatch.setattr(
"cmdeploy.lxc.cli.get_version_string",
lambda: "abc123def456",
)
assert "IN-SYNC" in cli._deploy_status(ct, "abc123def456", ix)
assert "STALE" in cli._deploy_status(ct, "other_hash_here", ix)
# Hash matches but local has uncommitted changes
monkeypatch.setattr(
"cmdeploy.lxc.cli.get_version_string",
lambda: "abc123def456\ndiff --git a/foo",
)
assert "DIRTY" in cli._deploy_status(ct, "abc123def456", ix)
monkeypatch.setattr(
"cmdeploy.lxc.incus.RelayContainer.deployed_version",
lambda _self: None,
)
assert "NOT DEPLOYED" in cli._deploy_status(ct, "abc123", ix)

View File

@@ -15,7 +15,7 @@ author = 'chatmail collective'
extensions = [
#'sphinx.ext.autodoc',
#'sphinx.ext.viewdoc',
#'sphinx.ext.viewcode',
'sphinxcontrib.mermaid',
]

View File

@@ -16,5 +16,6 @@ Contributions and feedback welcome through the https://github.com/chatmail/relay
proxy
migrate
overview
lxc
related
faq

271
doc/source/lxc.rst Normal file
View File

@@ -0,0 +1,271 @@
Local testing with LXC/Incus
============================
The ``cmdeploy`` tool includes support for running
chatmail relays inside local
`Incus <https://linuxcontainers.org/incus/>`_ LXC containers.
This is meant for development, testing, and CI
without requiring a remote server.
LXC system containers are lightweight virtual machines
that share the host's kernel but run their own init system,
package manager, and network stack,
so the cmdeploy deployment scripts work pretty much
as they would on a real Debian server or cloud VPS.
Prerequisites
-------------
Install `Incus <https://linuxcontainers.org/incus/>`_
(LXC container manager).
See the `official installation guide
<https://linuxcontainers.org/incus/docs/main/installing/>`_
for full details.
After installing incus, initialise and grant yourself access::
sudo incus admin init --minimal
sudo usermod -aG incus-admin $USER
.. caution::
Adding yourself to ``incus-admin`` grants effective root access
to the host: any member can mount host directories into a container
and manipulate them as root.
This is fine for local testing of your own relay branches,
but do **not** use it for production setups
or for testing untrusted relay branches from others.
.. warning::
You **must now log out and back in** (or run ``newgrp incus-admin``)
after adding yourself to the group.
Without this, all ``cmdeploy lxc-*`` commands
will fail with permission errors.
Verify the installation works by running ``incus list``,
which should print an empty table without errors.
Quick start
-----------
::
cd relay
scripts/initenv.sh # bootstrap venv
source venv/bin/activate # activate venv
cmdeploy lxc-test # create containers, deploy, test
The ``lxc-test`` command provides an automated way
to run the full deployment and test pipeline.
It executes several ``cmdeploy`` subcommands in sequential steps.
If a step fails, you can copy-paste the printed command
and run it manually to debug.
No host DNS delegation or ``~/.ssh/config`` changes are needed
because ``lxc-test`` passes the required SSH and DNS options directly.
CLI reference
--------------
``lxc-start [--ipv4-only] [--run] [NAME ...]``
Create and start containers.
Without arguments, creates ``test0-localchat`` and ``ns-localchat`` (DNS).
Pass one or more ``NAME`` arguments to create user relay containers instead
(e.g. ``cmdeploy lxc-start myrelay``).
Use ``--ipv4-only`` to set ``disable_ipv6 = True`` in the generated ``chatmail.ini``,
producing an IPv4-only relay.
Use ``--run`` to automatically run ``cmdeploy run`` on each container after starting it.
Generates ``lxconfigs/ssh-config``.
It reuses existing containers and resets DNS zones to minimal records.
``lxc-stop [--destroy] [--destroy-all] [NAME ...]``
Stop relay containers.
Without arguments, stops ``test0-localchat`` and ``test1-localchat``.
Pass ``NAME`` to stop specific containers.
Use ``--destroy`` to also delete the containers and their config files.
Use ``--destroy-all`` to additionally destroy
the ``ns-localchat`` DNS container **and** remove
the cached ``localchat-base`` and ``localchat-relay``
images, giving a fully clean slate for the next ``lxc-test``.
User containers are **never** destroyed unless named explicitly.
``lxc-test [--one]``
By default creates, deploys, and tests both ``test0`` and ``test1``
for dual-domain federation testing (sets ``CHATMAIL_DOMAIN2=_test1.localchat``).
test0 runs dual-stack (IPv4 + IPv6) while test1 runs IPv4-only (``disable_ipv6 = True``).
Pass ``--one`` to only deploy and test against ``test0``
(skips ``test1``, does not set ``CHATMAIL_DOMAIN2``).
``lxc-status``
Show live status of all LXC containers (including the DNS container),
deploy freshness (comparing ``/etc/chatmail-version``
against local ``git rev-parse HEAD`` and ``git diff``),
SSH config inclusion, and host DNS forwarding for ``.localchat``.
Reports **IN-SYNC**, **DIRTY** (hash matches but uncommitted changes exist),
**STALE** (different commit), or **NOT DEPLOYED**.
Container types
-----------------
**Test relay containers** (``test0-localchat``, ``test1-localchat``)
Created automatically by ``lxc-test``.
**test0** has IPv4 and IPv6 configured,
**test1** is IPv4-only (``disable_ipv6 = True``).
**User relay containers** (``<name>-localchat``)
Created by ``cmdeploy lxc-start <name>``
where ``<name>`` does not start with ``test``.
These are personal development instances,
never touched by ``lxc-stop --destroy`` unless named explicitly.
**DNS container** (``ns-localchat``)
Singleton container running PowerDNS.
Created automatically when any relay is started.
.. _lxc-ssh-config:
SSH configuration
-----------------
``cmdeploy lxc-start`` generates ``lxconfigs/ssh-config``,
a standard OpenSSH config file mapping every container name,
its domain, and a short alias to the container's IP address::
Host test0-localchat _test0.localchat _test0
Hostname 10.204.0.42
User root
IdentityFile /path/to/relay/lxconfigs/id_localchat
IdentitiesOnly yes
StrictHostKeyChecking accept-new
UserKnownHostsFile /dev/null
LogLevel ERROR
All ``cmdeploy`` commands (``run``, ``dns``, ``status``, ``test``)
accept ``--ssh-config lxconfigs/ssh-config`` to use this file.
``lxc-test`` passes it automatically.
**Using containers from the host shell:**
To make ``ssh _test0`` work from any terminal, add one line to ``~/.ssh/config``::
Include /absolute/path/to/relay/lxconfigs/ssh-config
.. _lxc-dns-setup:
.. _localchat-tld:
``.localchat`` DNS and name resolution
---------------------------------------
All LXC-managed chatmail domains use the ``.localchat`` pseudo-TLD
(e.g. ``_test0.localchat``, ``_test1.localchat``),
a non-delegated suffix that exists only within the local PowerDNS infrastructure.
A dedicated DNS container (``ns-localchat``)
is created so that local test relays interact
with DNS similar to a regular public Internet setup.
On first start, ``cmdeploy lxc-start`` creates this container
running two `PowerDNS <https://www.powerdns.com/>`_ services:
* **pdns-server** (authoritative) serves ``.localchat``
zones from a local SQLite database.
* **pdns-recursor** (recursive) listens on the Incus
bridge so all containers can use it.
Forwards ``.localchat`` queries to the local
authoritative server and resolves everything else recursively.
After the DNS container is up, ``lxc-start`` configures the Incus bridge
to advertise its IP via DHCP and disables Incus's own DNS.
DNS records are then created in two phases matching the "cmdeploy run" deployment flow:
1. **``lxc-start``** resets each relay zone to
**SOA, NS, and A** records (plus **AAAA** for dual-stack containers).
If host DNS resolution is configured, users can
afterwards run ``cmdeploy run --config lxconfigs/chatmail-test0.ini
--ssh-config lxconfigs/ssh-config --ssh-host _test0.localchat``.
LXC subcommands do not depend on host DNS resolution
and resolve addresses via ``lxconfigs/ssh-config``.
2. **``cmdeploy dns --zonefile``** generates a standard
BIND-format zone file (MX, TXT/SPF, TXT/DMARC,
TXT/MTA-STS, SRV, CNAME, DKIM) and loads it
into PowerDNS.
This two-phase approach prevents premature configuration of mail records
before the relay is actually deployed and running.
Once ``cmdeploy run`` deploys `Unbound <https://nlnetlabs.nl/projects/unbound/>`_
inside a relay container, Unbound has a configuration plugin snippet
that forwards all ``.localchat`` queries to the PowerDNS recursor,
and lets all other queries go through normal recursive resolution.
State outside the repository
-----------------------------
All generated configuration by lxc subcommands live in ``lxconfigs/``
(git-ignored), including the SSH key pair (``id_localchat``),
per-container ``chatmail-*.ini`` files, zone files, and ``ssh-config``.
The only state *outside* the repository is the Incus containers and images themselves
(managed via the ``incus`` CLI, labelled with ``user.localchat-managed=true``).
The Incus image store retains the following snapshot images:
* ``localchat-base``: Debian 12 with openssh-server and Python (built on first run)
* ``localchat-relay``: fully deployed relay snapshot,
cached after the first successful ``cmdeploy run``.
Subsequent relay containers launch from this image
so the deploy step is mostly no-ops (roughly 3× faster than a fresh deploy).
.. _lxc-tls:
TLS handling and underscore domains
------------------------------------
Container domains start with ``_`` (e.g. ``_test0.localchat``).
As described in :doc:`getting_started` ("Running a relay with self-signed certificates"),
underscore domains automatically use self-signed TLS
and ``smtp_tls_security_level = encrypt``.
This permits cross-relay federation between LXC containers
without any external certificate authority.
Delta Chat clients connecting to these relays
must be configured with
``certificateChecks = acceptInvalidCertificates``
(the test fixtures handle this automatically).
`PR #7926 on chatmail-core <https://github.com/chatmail/core/pull/7926>`_
is meant to make this special setting unnecessary for chatmail clients
that are connecting to underscore domains.
Known limitations
------------------
The LXC environment differs from a production
deployment in several ways:
**No ACME / Let's Encrypt**:
Self-signed TLS only (see :ref:`lxc-tls`);
ACME code paths are never exercised locally.
**No inbound connections from the internet**:
Containers sit on a private Incus bridge and are not port-forwarded.
Only the host and other containers on the same bridge can reach them.
**Local federation only**:
Cross-relay mail delivery (e.g. test0 → test1) works between containers on the same host,
but these relays are invisible to any external mail server.
**DNS is local only**:
The ``.localchat`` pseudo-TLD is not resolvable from the wider internet
(see :ref:`lxc-dns-setup`).
**IPv6 is ULA-only**:
Containers receive IPv6 addresses from the ``fd42:...`` ULA range on the Incus bridge.
These are not globally routable, but are sufficient for testing IPv6 service binding
(Postfix, Dovecot, Nginx) and DNS AAAA records inside the local environment.
test1 runs with ``disable_ipv6 = True`` to exercise the IPv4-only deployment path.