nixos-anywhere-pxe: explicitly print nixos-anywhere cmd including the ssh key

this allows the user to just copy paste the command and run it manually, in case it failed

Author: pogobanane

src/nixos_anywhere_pxe/__init__.py

@@ -335,8 +335,7 @@ def ssh_private_key() -> Iterator[SshKey]:
 def nixos_anywhere(
     ip: str, flake: str, ssh_private_key: Path, nixos_anywhere_args: List[str]
 ) -> None:
-    run(
-        [
+    cmd = [
             # FIXME: path
             "bash",
             str(NIXOS_ANYWHERE_SH),
@@ -346,11 +345,13 @@ def nixos_anywhere(
             # do not substitute because we do not have internet and copying locally is faster.
             "--no-substitute-on-destination",
             ip,
-        ]
-        + nixos_anywhere_args,
+        ] + nixos_anywhere_args
+    run(cmd,
         extra_env=dict(SSH_PRIVATE_KEY=ssh_private_key.read_text()),
         check=False,
     )
+    print(f"If the installation failed, you may run the install command manually again:")
+    print(f"{cmd} -i {ssh_private_key.read_text()}")
 
 
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