Create cmdlineparmsample1.py

qshpython/cmdlineparmsample1.py

@@ -0,0 +1,196 @@
+#!/QOpenSys/pkgs/bin/python3
+#------------------------------------------------
+# Script name: cmdlineparmsample1.py
+#
+# Description: 
+# This script is a good example of adding flexible  
+# command line parameter processing and parm validation
+# without caring which position a parm is passed in.
+#
+# Parameters:
+# --inputfile - Input file name
+# Valid formats: --inputfile=filename.txt  or 
+#                --inputfile filename.txt     
+#                --inputfile="filename.txt"
+#                --inputfile "filename.txt"
+#
+# --outputfile - Output file name
+# Valid formats: --outputfile=filename.txt  or 
+#                --outputfile filename.txt     
+#                --outputfile="filename.txt"
+#                --outputfile "filename.txt"
+#
+# --replace - Replace existing=True-replace, False-Do not replace
+# Valid formats: --replace=true  or 
+#                --replace true     
+#                --replace="filename.txt"
+#                --replace "filename.txt"
+#
+# Pip packages needed:
+# None - argparse is a standard module.
+#
+# Web reference links:
+# http://zetcode.com/python/argparse/
+# https://stackoverflow.com/questions/5943249/python-argparse-and-controlling-overriding-the-exit-status-code
+# https://www.techbeamers.com/use-try-except-python/
+# argument parse exceptions
+# https://stackoverflow.com/questions/8107713/using-argparse-argumenterror-in-python
+#------------------------------------------------
+
+import argparse
+import sys
+from sys import platform
+import os
+import re
+import time
+import traceback
+from pathlib import Path
+from datetime import date
+import datetime
+
+#------------------------------------------------
+# Script initialization
+#------------------------------------------------
+
+# Initialize or set variables
+appname="Command Line Parser Sample"
+exitcode=0 #Init exitcode
+exitmessage=''
+dashes="-------------------------------------------------------------------"
+today=date.today()
+curr_date = datetime.datetime.now()
+parmsexpected=6;
+datestamp=time.strftime("%Y%m%d")
+timestamp=time.strftime("%H%M%S")
+datetime2=time.strftime("%d%H%M%S")
+datetime3=time.strftime("%m/%d/%y-%H%M%S")
+
+# Create parm variables
+inputfile=""
+outputfile=""
+replace=""
+
+#------------------------------------------------
+# Define some useful functions
+#------------------------------------------------
+
+def str2bool(strval):
+    #-------------------------------------------------------
+    # Function: str2bool
+    # Desc: Constructor
+    # :strval: String value for true or false
+    # :return: Return True if string value is" yes, true, t or 1
+    #-------------------------------------------------------
+    return strval.lower() in ("yes", "true", "t", "1")
+
+def trim(strval):
+    #-------------------------------------------------------
+    # Function: trim
+    # Desc: Alternate name for strip
+    # :strval: String value to trim. 
+    # :return: Trimmed value
+    #-------------------------------------------------------
+    return strval.strip()
+
+def rtrim(strval):
+    #-------------------------------------------------------
+    # Function: rtrim
+    # Desc: Alternate name for rstrip
+    # :strval: String value to trim. 
+    # :return: Trimmed value
+    #-------------------------------------------------------
+    return strval.rstrip()
+
+def ltrim(strval):
+    #-------------------------------------------------------
+    # Function: ltrim
+    # Desc: Alternate name for lstrip
+    # :strval: String value to ltrim. 
+    # :return: Trimmed value
+    #-------------------------------------------------------
+    return strval.lstrip()
+
+#------------------------------------------------
+# Main script logic
+#------------------------------------------------
+
+# Output messages to STDOUT for logging
+print(dashes)
+print(appname)
+print("Start of Main Processing - " + time.strftime("%H:%M:%S"))
+print("OS:" + platform)
+
+try: # Try to perform main logic      
+
+
+   # Set up the command line argument parsing.
+   # If the parse_args function fails, the program will
+   # exit with an error 2. In Python 3.9, there is 
+   # an argument to prevent an auto-exit
+   # Each argument has a long and short version
+   parser = argparse.ArgumentParser()
+   parser.add_argument('-i','--inputfile', required=True,help="Input filename")
+   parser.add_argument('-o','--outputfile', required=True,help="Output file name")
+   #parser.add_argument('-r','--replace',help="True=Replace output file,False=Do not replace output file. Default=False")
+   parser.add_argument('-r','--replace',default="False",required=False,help="True=Replace output file,False=Do not replace output file. Default=False")
+   # Parse the command line arguments 
+   args = parser.parse_args()
+
+   # Pull arguments into variables so they are meaningful
+   inputfile=args.inputfile.upper().strip()
+   outputfile=args.outputfile.strip()
+   # If replace parm passed, use passed value instead of default
+   replace=str2bool(args.replace.strip())
+
+   # Argument parsing is done. Let's do some work
+   # In our case we will just PRINT the variables 
+   # to the console. Good for debugging or logging
+   print(dashes)
+   print("Parameters:")
+   print(f"Script file: {sys.argv[0]}")
+   print(f"Input file: {inputfile}")
+   print(f"Output file: {outputfile}")
+   print(f"Replace file: {replace}")   
+
+   # Set success info
+   exitcode=0
+   exitmessage=f"Parameter sample ran successfully."
+
+#------------------------------------------------
+# Handle Exceptions
+#------------------------------------------------
+# System Exit occurred. Most likely from argument parser
+except SystemExit as ex:
+     #print("Command line argument error.")
+     #######print("Command line arguments triggered script exit.")
+     exitcode=ex.code # set return code for stdout
+     exitmessage=str(ex) # set exit message for stdout
+     ###Enable the following for detailed trace
+     ###print('Traceback Info') # output traceback info for stdout
+     ###traceback.print_exc()      
+
+except argparse.ArgumentError as exc:
+     exitcode=99 # set return code for stdout
+     exitmessage=str(exc) # set exit message for stdout
+     print('Traceback Info') # output traceback info for stdout
+     traceback.print_exc()      
+     sys.exit(99)
+
+except Exception as ex: # Catch and handle exceptions
+     exitcode=99 # set return code for stdout
+     exitmessage=str(ex) # set exit message for stdout
+     print('Traceback Info') # output traceback info for stdout
+     traceback.print_exc()        
+     sys.exit(99)
+#------------------------------------------------
+# Always perform final processing
+#------------------------------------------------
+finally: # Final processing
+     # Do any final code and exit now
+     # We log as much relevent info to STDOUT as needed
+     print("")
+     print(dashes)
+     print('ExitCode:' + str(exitcode))
+     print('ExitMessage:' + exitmessage)
+     print("End of Main Processing - " + time.strftime("%H:%M:%S"))
+     print(dashes)