cmdeploy: prepare chatmaild/cmdeploy changes for Docker support

- chatmaild:
  - basedeploy.py: Add has_systemd() guard. During Docker image builds
    there's no running systemd, so deployers that query SystemdEnabled
    facts would crash; this change might also be helpful for non-systemd
    platforms.
- cmdeploy:
  - cmdeploy.py:
    - when deploying to @docker, auto-set CHATMAIL_NOPORTCHECK and
      CHATMAIL_NOSYSCTL since neither makes sense inside a container
    - --config default now reads CHATMAIL_INI env var, so Docker
      entrypoints can point to a mounted ini without CLI flags.
  - deployers.py:
    - skip port check / CHATMAIL_NOPORTCHECK
    - skip echobot systemd cleanup w/ has_systemd
  - dovecot/deployer.py:
    - Guard sysctl writes behind CHATMAIL_NOSYSCTL
    - invert dovecot install check so it works without systemd
  - sshexec.py: Add __call__ to LocalExec so cmdeploy status works with
    @local target. Without it, cmdeploy status tried to call the
    executor directly and got TypeError.

Consolidated from j4n/docker branch commits (selection):
- 8953fde feat(cmdeploy): read CHATMAIL_INI env var for default --config path
- 81d7782 fix(cmdeploy): add __call__ to LocalExec so status works with @local
- 8bba78e docker: disable port check if docker is running. fix #694
- 865b514 docker: replace config flags with env vars, drop docker param (instead of f26cb08)

Files: cmdeploy/src/cmdeploy/{basedeploy,cmdeploy,deployers,sshexec,dovecot/deployer}.py

Co-authored-by: Keonik1 <keonik.dev@gmail.com>
Co-authored-by: missytake <missytake@systemli.org>

cmdeploy/src/cmdeploy/basedeploy.py

@@ -5,6 +5,11 @@ import os
 from pyinfra.operations import files, server, systemd
 
 
+def has_systemd():
+    """Returns False during Docker image builds or any other non-systemd environment."""
+    return os.path.isdir("/run/systemd/system")
+
+
 def get_resource(arg, pkg=__package__):
     return importlib.resources.files(pkg).joinpath(arg)
 

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -110,6 +110,9 @@ def run_cmd(args, out):
 
     cmd = f"{pyinf} --ssh-user root {ssh_host} {deploy_path} -y"
     if ssh_host in ["localhost", "@docker"]:
+        if ssh_host == "@docker":
+            env["CHATMAIL_NOPORTCHECK"] = "True"
+            env["CHATMAIL_NOSYSCTL"] = "True"
         cmd = f"{pyinf} @local {deploy_path} -y"
 
     if version.parse(pyinfra.__version__) < version.parse("3"):
@@ -336,7 +339,7 @@ def add_config_option(parser):
         "--config",
         dest="inipath",
         action="store",
-        default=Path("chatmail.ini"),
+        default=Path(os.environ.get("CHATMAIL_INI", "chatmail.ini")),
         type=Path,
         help="path to the chatmail.ini file",
     )

cmdeploy/src/cmdeploy/deployers.py

@@ -2,6 +2,7 @@
 Chat Mail pyinfra deploy.
 """
 
+import os
 import shutil
 import subprocess
 import sys
@@ -26,6 +27,7 @@ from .basedeploy import (
     activate_remote_units,
     configure_remote_units,
     get_resource,
+    has_systemd,
 )
 from .dovecot.deployer import DovecotDeployer
 from .filtermail.deployer import FiltermailDeployer
@@ -66,6 +68,8 @@ def _build_chatmaild(dist_dir) -> None:
 
 
 def remove_legacy_artifacts():
+    if not has_systemd():
+        return
     # disable legacy doveauth-dictproxy.service
     if host.get_fact(SystemdEnabled).get("doveauth-dictproxy.service"):
         systemd.service(
@@ -300,7 +304,7 @@ class LegacyRemoveDeployer(Deployer):
             present=False,
         )
         # remove echobot if it is still running
-        if host.get_fact(SystemdEnabled).get("echobot.service"):
+        if has_systemd() and host.get_fact(SystemdEnabled).get("echobot.service"):
             systemd.service(
                 name="Disable echobot.service",
                 service="echobot.service",
@@ -567,6 +571,7 @@ def deploy_chatmail(config_path: Path, disable_mail: bool, website_only: bool) -
             Out().red(f"Deploy failed: mtail_address {config.mtail_address} is not available (VPN up?).\n")
             exit(1)
 
+    if not os.environ.get("CHATMAIL_NOPORTCHECK"):
         port_services = [
             (["master", "smtpd"], 25),
             ("unbound", 53),

cmdeploy/src/cmdeploy/dovecot/deployer.py

@@ -1,3 +1,5 @@
+import os
+
 from chatmaild.config import Config
 from pyinfra import host
 from pyinfra.facts.server import Arch, Sysctl
@@ -9,6 +11,7 @@ from cmdeploy.basedeploy import (
     activate_remote_units,
     configure_remote_units,
     get_resource,
+    has_systemd,
 )
 
 
@@ -22,7 +25,8 @@ class DovecotDeployer(Deployer):
 
     def install(self):
         arch = host.get_fact(Arch)
-        if not host.get_fact(SystemdEnabled).get("dovecot.service"):
+        if has_systemd() and "dovecot.service" in host.get_fact(SystemdEnabled):
+            return  # already installed and running
         _install_dovecot_package("core", arch)
         _install_dovecot_package("imapd", arch)
         _install_dovecot_package("lmtpd", arch)
@@ -116,6 +120,7 @@ def _configure_dovecot(config: Config, debug: bool = False) -> (bool, bool):
 
     # as per https://doc.dovecot.org/2.3/configuration_manual/os/
     # it is recommended to set the following inotify limits
+    if not os.environ.get("CHATMAIL_NOSYSCTL"):
         for name in ("max_user_instances", "max_user_watches"):
             key = f"fs.inotify.{name}"
             if host.get_fact(Sysctl)[key] > 65535: