create-vm in py

1 files changed, 96 insertions, 73 deletions

diff --git a/create-vm b/create-vm
index 3fe4544..454db06 100755
--- a/create-vm
+++ b/create-vm
@@ -1,83 +1,106 @@
-#!/bin/bash
+#!/usr/bin/env python3
 
-set -eu -o pipefail
+import os
+import shutil
+import socket
+import subprocess
+import sys
+import tempfile
+import time
 
-cloud_init_iso()
-{
-    local iso="$1"
-    local hostname="$2"
-    local pubkey="$3"
-    local dir="$(mktemp -d)"
 
-    cat <<EOF > "$dir/meta-data"
+def cloud_init_iso(iso, hostname, pubkey):
+    tmp = tempfile.mkdtemp()
+
+    with open(os.path.join(tmp, "meta-data"), "w") as f:
+        f.write(
+            f"""\
 # Amazon EC2 style metadata
-local-hostname: $hostname
-EOF
+local-hostname: {hostname}
+"""
+        )
 
-    cat <<EOF > "$dir/user-data"
+    with open(os.path.join(tmp, "user-data"), "w") as f:
+        f.write(
+            f"""\
 #cloud-config
 ssh_authorized_keys:
-- $pubkey
-EOF
-
-    genisoimage -quiet -volid cidata -joliet -rock -output "$iso" "$dir"
-    rm -rf "$dir"
-}
-
-
-create_vm()
-{
-    local name="$1"
-    local memory="$2"
-    local cpus="$3"
-    local image="$4"
-    local iso="$5"
-
-    virt-install \
-	--name="$name" \
-	--memory "$memory" \
-	--vcpus "$cpus" \
-	--disk="path=$image,cache=none" \
-	--disk="path=$iso,readonly=on" \
-	--network=network=default \
-	--quiet \
-	--connect qemu:///system \
-	--cpu=host-passthrough \
-	--os-variant=debian9 \
-	--import \
-	--graphics=spice \
-	--noautoconsole
-}
-
-wait_for_ssh()
-{
-    local host="$1"
-    while ! nc -w 1 "$host" 22 < /dev/null > /dev/null
-    do
-	sleep 5
-    done
-}
+- {pubkey}
+"""
+        )
+
+    subprocess.check_call(
+        [
+            "genisoimage",
+            "-quiet",
+            "-volid",
+            "cidata",
+            "-joliet",
+            "-rock",
+            "-output",
+            iso,
+            tmp,
+        ]
+    )
+    shutil.rmtree(tmp)
+
+
+def create_vm(vm, image, iso, memory=1024, cpus=1):
+    subprocess.check_call(
+        [
+            "virt-install",
+            "--name",
+            vm,
+            "--memory",
+            str(memory),
+            "--vcpus",
+            str(cpus),
+            f"--disk=path={image},cache=none",
+            f"--disk=path={iso},readonly=on",
+            "--network=network=default",
+            "--connect",
+            "qemu:///system",
+            "--cpu=host-passthrough",
+            "--os-variant=debian9",
+            "--import",
+            "--graphics=spice",
+            "--noautoconsole",
+            "--quiet",
+        ]
+    )
+
+
+def wait_for_ssh(hostname):
+    ssh_port = 22
+    while True:
+        time.sleep(5)
+        try:
+            conn = socket.create_connection((hostname, ssh_port), timeout=1)
+        except Exception:
+            continue
+        conn.close()
+        break
+
+
+def main():
+    base, vm, memory, cpus, img, size, pubkey = sys.argv[1:]
+
+    memory = int(memory)
+    cpus = int(cpus)
+    pubkey = open(pubkey).read()
+
+    iso = f"{vm}.iso"
+    cloud_init_iso(iso, vm, pubkey)
+
+    if os.path.exists(img):
+        os.remove(img)
+    shutil.copy(base, img)
+
+    subprocess.check_call(["qemu-img", "resize", "-q", img, size])
+
+    create_vm(vm, img, iso, memory=memory, cpus=cpus)
+    wait_for_ssh(vm)
+    os.remove(iso)
 
 
 main()
-{
-    local base="$1"
-    local vm="$2"
-    local memory="$3"
-    local cpus="$4"
-    local img="$5"
-    local size="$6"
-    local pubkey="$(cat "$7")"
-
-    local iso="$vm.iso"
-
-    cloud_init_iso "$vm.iso" "$vm" "$pubkey"
-    cp "$base" "$img"
-    qemu-img resize -q "$img" "$size"
-    create_vm "$vm" "$memory" "$cpus" "$img" "$iso"
-    wait_for_ssh "$vm"
-    rm -f "$iso"
-}
-
-
-main "$@"