take hostname from command line

main.py

@@ -1,15 +1,17 @@
 # TODO
-#  Implement Monitoring of VM
+#  1. Verify that commands successfully did what they are
+#     supposed to do by querying state of VM using QMP.
+#  2. Implement Monitoring of VM.
+
+
+# For QEMU Monitor Protocol Commands Information, See
+# https://qemu.weilnetz.de/doc/qemu-doc.html#pcsys_005fmonitor
 
 import json
 import shutil
 import os
 import subprocess
-
-# For Commands Information
-# https://qemu.weilnetz.de/doc/qemu-doc.html#pcsys_005fmonitor
-
-
+import argparse
 import qmp
 
 from etcd3_wrapper import Etcd3Wrapper
@@ -18,7 +20,9 @@ from decouple import config
 
 def get_vm_start_cmd(owner_dir, vm_uuid):
     vm_sock_flags = f"-qmp unix:{owner_dir}/.vm/{vm_uuid}-sock,server,nowait"
-    vm_start_command_flags = f"-boot c -net nic -net user -m 256 {vm_sock_flags} -daemonize"
+    vm_start_command_flags = (
+        f"-boot c -net nic -net user -m 256 {vm_sock_flags} -daemonize"
+    )
     vm_start_command = f"""qemu-system-x86_64 {owner_dir}/.vm/{vm_uuid}.raw {vm_start_command_flags}"""
     return vm_start_command
 
@@ -32,9 +36,8 @@ def get_qemu_mon(sock_file):
     return m
 
 
-def main():
+def main(hostname):
     client = Etcd3Wrapper()
-    hostname = config("HOST_NAME")
 
     events = client.watch_prefix("/v1/vm/")
 
@@ -105,11 +108,17 @@ def main():
                 client.put(e.key, e.value, value_in_json=True)
             else:
                 print("Starting VM")
-                subprocess.run(get_vm_start_cmd(owner_dir, vm_uuid).split(" "))
+                subprocess.run(
+                    get_vm_start_cmd(owner_dir, vm_uuid).split(" ")
+                )
                 e.value["status"] = "RUNNING"
                 client.put(e.key, e.value, value_in_json=True)
         else:
             continue
 
 
-main()
+argparser = argparse.ArgumentParser()
+argparser.add_argument("hostname", help="Name of this host. e.g /v1/host/1")
+args = argparser.parse_args()
+
+main(args.hostname)