Initial Commit

vm/host/owuivm-guest-run

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+"""Push a local script into the running maintenance guest and run it.
+
+    sudo owuivm-guest-run vm/images/ubuntu/by-hand.sh
+
+WHY THIS EXISTS
+
+Preparing a base image by hand means typing into a VNC console, and the
+list of things to do to it is a hundred lines long. Everything on that
+list is ordinary shell, so the only real problem is getting the text in
+there - and the machine already has a channel for exactly that, the same
+one every session uses.
+
+It needs qemu-guest-agent inside the guest, which is also the one thing
+on that list that genuinely has to be typed by hand: it is what this
+speaks to. So the sequence is always "install the guest agent by hand,
+then push the rest".
+
+Deliberately the maintenance socket only. A session's guest belongs to
+the agent, and a way to inject a script into it from the host is not
+something this host should own.
+"""
+from __future__ import annotations
+
+import sys
+
+sys.path.insert(0, "/usr/local/lib/owuivm")
+
+from guest import Guest, GuestError  # noqa: E402
+
+SOCKET = "/run/owuivm/00000000000000000000000000000000/ga.sock"
+
+
+def main(argv: list[str]) -> int:
+    if len(argv) != 2:
+        print(f"usage: {argv[0]} <script>", file=sys.stderr)
+        return 64
+    with open(argv[1], "rb") as handle:
+        body = handle.read()
+    remote = "/root/" + argv[1].rsplit("/", 1)[-1]
+
+    try:
+        with Guest(SOCKET, timeout=30.0) as agent:
+            if not agent.ping(timeout=10.0):
+                raise GuestError("the guest agent did not answer")
+            agent.write_file(remote, body)
+            print(f"pushed {len(body)} bytes to {remote}; running it\n", flush=True)
+            # No timeout worth arguing about: this installs packages over
+            # a link that is as fast as the host's, and a run that is
+            # still going is not a run that has failed.
+            result = agent.shell(f"bash {remote}", timeout_s=1800.0)
+    except (GuestError, OSError) as exc:
+        print(f"could not reach the machine: {exc}", file=sys.stderr)
+        print("\nIs it running, and is qemu-guest-agent installed inside it?"
+              "\n  sudo apt install -y qemu-guest-agent"
+              "\n  sudo systemctl enable --now qemu-guest-agent", file=sys.stderr)
+        return 69
+
+    sys.stdout.write(result["stdout"])
+    if result["stderr"].strip():
+        sys.stderr.write("\n-- stderr --\n" + result["stderr"])
+    print(f"\nexit code: {result['exit_code']}  ({result['seconds']}s)")
+    return 0 if result["exit_code"] == 0 else 1
+
+
+if __name__ == "__main__":
+    raise SystemExit(main(sys.argv))