Better argument parsing for getpubkeys

App/getpubkeys

@@ -6,8 +6,9 @@
 # which we capture.  At the end, output all of the public keys to a
 # pubkeys.yaml file.
 
-# Usage: mkpubkeys [manifestfile.yaml [pubkeyfile.yaml]]
+# Usage: getpubkeys [-m manifest.yaml] [-p pubkeys.yaml]
 
+import argparse
 import re
 import shlex
 import subprocess
@@ -47,16 +48,20 @@ def getkey(node, manifestdata):
     return pubkey
 
 if __name__ == "__main__":
-    if len(sys.argv) > 1:
-        MANIFEST = sys.argv[1]
-    if len(sys.argv) > 2:
-        PUBKEYS = sys.argv[2]
+    aparse = argparse.ArgumentParser(
+        description='Create a TEEMS pubkeys.yaml file from a manifest.yaml file'
+    )
+    aparse.add_argument('-m', default=MANIFEST,
+        help='manifest.yaml input file')
+    aparse.add_argument('-p', default=PUBKEYS,
+        help='pubkeys.yaml output file')
+    args = aparse.parse_args()
 
     # A dictionary to store the output pubkeys
     pubkeys = {}
 
     # Read the manifest
-    with open(MANIFEST) as mf:
+    with open(args.m) as mf:
         manifest = yaml.safe_load(mf)
         for (node, data) in manifest.items():
             key = getkey(node, data)
@@ -65,5 +70,5 @@ if __name__ == "__main__":
 
     print('')
     print(yaml.dump(pubkeys))
-    with open(PUBKEYS, 'w') as pf:
+    with open(args.p, 'w') as pf:
         yaml.dump(pubkeys, pf)