echobot: print invite link with python

The entire stack is setup to support 'localhost'  as a value for
ssh_host, returning LocalExec when that is the case, but this last step
made a new explicit SSHExec connection to config.mail_domain.

This changes that to simply use the subprocess module when ssh_host is
local.

This also fixes the issue where the connection was made to
'config.mail_domain' instead of the supplied ssh_host value, ensuring
that remains consistent.

Additionally, the entire process will be skipped if --dry-run is used
with cmdeploy, allowing a dry-run to complete without error.

CHANGELOG.md

@@ -11,6 +11,9 @@
 - Organized cmdeploy into install, configure, and activate stages
   ([#695](https://github.com/chatmail/relay/pull/695))
 
+- echobot: print invite-link also if it's deployed locally
+  ([#751](https://github.com/chatmail/relay/pull/751))
+
 - docs: move readme.md docs to sphinx documentation rendered at https://chatmail.at/doc/relay 
   ([#711](https://github.com/chatmail/relay/pull/711))
 

cmdeploy/src/cmdeploy/cmdeploy.py

@@ -11,6 +11,7 @@ import pathlib
 import shutil
 import subprocess
 import sys
+import time
 from pathlib import Path
 
 import pyinfra
@@ -109,15 +110,22 @@ def run_cmd(args, out):
     try:
         retcode = out.check_call(cmd, env=env)
         if retcode == 0:
-            if not args.disable_mail:
+            if not args.disable_mail and not args.dry_run:
                 print("\nYou can try out the relay by talking to this echo bot: ")
-                sshexec = SSHExec(args.config.mail_domain, verbose=args.verbose)
-                print(
-                    sshexec(
-                        call=remote.rshell.shell,
-                        kwargs=dict(command="cat /var/lib/echobot/invite-link.txt"),
+                invite_path = Path("/var/lib/echobot/invite-link.txt")
+                if ssh_host in ["localhost", "@local", "@docker"]:
+                    while not invite_path.exists():
+                        time.sleep(0.1)
+                    with invite_path.open() as f:
+                        print(f.readline())
+                else:
+                    echo_sshexec = get_sshexec(ssh_host, verbose=args.verbose)
+                    print(
+                        echo_sshexec(
+                            call=remote.rshell.shell,
+                            kwargs=dict(command=f"cat {invite_path}"),
+                        )
                     )
-                )
             out.green("Deploy completed, call `cmdeploy dns` next.")
         elif not remote_data["acme_account_url"]:
             out.red("Deploy completed but letsencrypt not configured")