I wrote a simple program to encode a local text file with password and decode it back. There is one text file and it is either enocoded with password or is in plain text.
I had a version in python for this, but nim compiles to an executable, so I gave it a try.
I'm not perfectly happy with command line argument handling, as well as with some repeated code in
case statement, but maybe there are other things to improve too.
import os import system import strutils import terminal import xxtea const FILENAME = "passwords.txt" const USAGE = """Encrypt and decrypt a file using a password. Usage: vault open [file] vault close [file] Default file: passwords.txt WARNING: this program may overwrite or delete file content without a possibilty of recovery. Passwords cannot be recovered. Information can be destroyed by repeated attempts of encryption/decryption. Use at you own risk. """ proc getpass(message: string = "Password: "): string = return terminal.readPasswordFromStdin(message) proc getpass2(): string = let key = getpass() let key2 = getpass("Repeat password: ") if key == key2: return key else: quitWithMessage("Passwords do not match") proc write(content: string): void = writeFile(filepath(), content) proc notify(message: string): void = echo message, " ", filepath() # cli args helpers proc filepath(): string = try: return paramStr(2) except IndexError: return FILENAME proc command(): string = try: return paramStr(1).toLowerAscii() except IndexError: quitWithMessage(USAGE) # flow control proc quitWithMessage(message: string): void = echo message quit(1) # main if command() notin ["open", "close", "help"]: quitWithMessage(USAGE) let existingContent = readFile(filepath()) case command() of "open": let key = getpass() let newContent = xxtea.decrypt(existingContent, key) write(newContent) notify("Decoded") of "close": let key = getpass2() let newContent = xxtea.encrypt(existingContent, key) write(newContent) notify("Encoded") of "help": quitWithMessage(USAGE)
EDIT: I noticed nim has
try... except statement and used it with