cleanin up coding conventions

files/fimplate.py

@@ -1,73 +1,100 @@
 #!/usr/bin/env python
 import sys,re,os
-from argparse import ArgumentParser 
+from argparse import ArgumentParser
 from argparse import RawTextHelpFormatter
+
 def setup_options():
-    parser=ArgumentParser(description="""Template Filler
-    
+    parser = ArgumentParser(
+        description="""Template Filler
+
 === Template example: ===
   Hello [[name]]!
-[[letter]]  
+[[letter]]
 
 == Value file/Value pair example: ==
 [[name]]=John
-[[letter]]=@letter.txt 
-    """,formatter_class=RawTextHelpFormatter)
-    parser.add_argument("-e",action="store_true",dest="env",default=False,
-                      help="Use the environment to replace ${env} style variables.")
-    parser.add_argument("-f",action="store",dest="file",
-                      help="File name to read keys/values.")
-    parser.add_argument("-p",action="append",dest="values",default=[],
-                     help="key=value pairs. This option may be issued several times.")
-    parser.add_argument('template', action="store", nargs='?',
-                    help="Template file to be filled. If not defined, stdin used.")
-    options=parser.parse_args()
+[[letter]]=@letter.txt
+    """,
+        formatter_class = RawTextHelpFormatter
+    )
+    parser.add_argument(
+        "-e",
+        action = "store_true",
+        dest = "env",
+        default = False,
+        help = "Use the environment to replace ${env} style variables."
+    )
+    parser.add_argument(
+        "-f",
+        action = "store",
+        dest = "file",
+        help = "File name to read keys/values."
+    )
+    parser.add_argument(
+        "-p",
+        action = "append",
+        dest = "values",
+        default = [],
+        help = "key=value pairs. This option may be issued several times."
+    )
+    parser.add_argument(
+        'template',
+        action = "store",
+        nargs = '?',
+        help = "Template file to be filled. If not defined, stdin used."
+    )
+    options = parser.parse_args()
     return options
 
+
 def parse_file(filename):
-    pairs=[]
-    with open(filename,"r") as reader:
-        for i,l in enumerate(reader):
-            l=l.rstrip("\n\r")
-            if len(l)==0:
+    pairs = []
+    with open(filename, "r") as reader:
+        for i, l in enumerate(reader):
+            l = l.rstrip("\n\r")
+            if len(l) == 0:
                 continue
             tokens = l.split('=', 1)
-            if len(tokens)!=2:
-                print("File %s:%i key=value pair '%s' does not parse"%(filename,i+1,l,))
-                sys.exit(1) 
+            if len(tokens) != 2:
+                print("File %s:%i key=value pair '%s' does not parse"%(
+                    filename, i+1, l,
+                ))
+                sys.exit(1)
             pairs.append( (tokens[0], tokens[1].decode('string_escape')) )
     return pairs
 
 def parse_arguments(args):
-    pairs=[]
+    pairs = []
     for p in args:
         tokens = p.split('=', 1)
-        if len(tokens)!=2:
+        if len(tokens) != 2:
             print("Argument key=value pair '%s' does not parse"%(p,))
-            sys.exit(1) 
+            sys.exit(1)
         pairs.append( (tokens[0], tokens[1].decode('string_escape')) )
     return pairs
 
-options=setup_options();
-pairs=[]
-if options.file!=None:
-    pairs.extend(parse_file(options.file))
-pairs.extend(parse_arguments(options.values))
-if options.template==None:
-    in_reader=sys.stdin
-else:
-    in_reader=open(options.template,'rb')
-for l in in_reader:
-    for p in pairs:
-        value=p[1]
-        if len(value)>0:
-            if value[0]=="@":
-                value=open(value[1:],'rt').read()
-            elif value[0:2]=="\\@":
-                value=value[1:]
-        l=l.replace(p[0],value)
-    if options.env:
-        var_list=[m.group(0) for m in re.finditer('\${[^ ]+}', l)]
-        for v in var_list:
-            l=l.replace(v,os.environ.get(v[:-1][2:],""))
-    sys.stdout.write(l)
+
+if __name__ == "__main__":
+    options = setup_options();
+    pairs = []
+    if options.file != None:
+        pairs.extend(parse_file(options.file))
+    pairs.extend(parse_arguments(options.values))
+    if options.template == None:
+        in_reader = sys.stdin
+    else:
+        in_reader = open(options.template, 'rb')
+    for l in in_reader:
+        for p in pairs:
+            value = p[1]
+            if len(value) > 0:
+                if value[0] == "@":
+                    value = open(value[1:], 'rt').read()
+                elif value[0:2] == "\\@":
+                    value = value[1:]
+            l = l.replace(p[0], value)
+        if options.env:
+            var_list = [m.group(0) for m in re.finditer('\${[^ ]+}', l)]
+            for v in var_list:
+                l = l.replace(v, os.environ.get(v[:-1][2:], ""))
+        sys.stdout.write(l)