Process txt files instead of CSV

Generate salt and write with n,r,p parameters as a first line of the
outfile.

userhash.py

@@ -2,15 +2,14 @@
 """Pseudonymize data."""
 
 import argparse
-import json
+import base64
 import sys
-from csv import DictReader
+from secrets import token_bytes
 
 try:
     from hashlib import scrypt
 except ImportError:
     from scrypt import hash
-
     def scrypt(password, salt, n, r, p):
         return hash(password, salt, n, r, p)
 
@@ -18,7 +17,7 @@ except ImportError:
 MIN_SALT_LENGTH = 16
 
 arg_parser = argparse.ArgumentParser(
-    description='Apply scrypt to every row of csv file',
+    description='Apply scrypt to every row of txt file. Salt, N, r and p parameters will be written as a first line',
     epilog=(
         'Please use hashes only for reconciliation. ' +
         'Do not store them more than it is needed for reconciliation. ' +
@@ -51,17 +50,18 @@ arg_parser.add_argument(
     help='parallelization factor (default: {0})'.format(DEFAULT_SCRYPT_P),
 )
 arg_parser.add_argument(
-    'salt',
-    default=sys.stdin,
-    type=lambda in_str: in_str.encode('utf-8'),
-    help='salt for scrypt (minimum: 16 bytes)',
+    '-s',
+    '--salt',
+    default=token_bytes(32),
+    type=lambda in_str: base64.b64decode(in_str),
+    help='base64 encoded salt for scrypt (minimum: 16 bytes)',
 )
 arg_parser.add_argument(
     'infile',
     nargs='?',
     type=argparse.FileType('r'),
     default=sys.stdin,
-    help='Comma Separated Values file (CSV) with header (default: stdin)',
+    help='text file to be hashed line by line (default: stdin)',
 )
 arg_parser.add_argument(
     'outfile',
@@ -81,16 +81,24 @@ if len(args.salt) < MIN_SALT_LENGTH:
     raise ValidationException('Salt shall be longer than 16 bytes')
 
 with args.infile:
-    reader = DictReader(args.infile)
     with args.outfile:
-        for row in reader:
-            args.outfile.writelines((
-                scrypt(
-                    json.dumps(row, sort_keys=True).lower().encode('utf-8'),
-                    salt=args.salt,
-                    n=args.n,
-                    r=args.r,
-                    p=args.p,
-                ).hex(),
-                '\n',
-            ))
+        args.outfile.write(
+            ' '.join((
+                base64.b64encode(args.salt).decode('ascii'),
+                str(args.n),
+                str(args.r),
+                str(args.p),
+            )) + '\n',
+        )
+        for row in args.infile:
+            args.outfile.write(
+                base64.b85encode(
+                    scrypt(
+                        row.rstrip('\n').encode('utf-8'),
+                        salt=args.salt,
+                        n=args.n,
+                        r=args.r,
+                        p=args.p,
+                    ),
+                ).decode('ascii') + '\n',
+            )