Hello folks,
Am having issues completing this project: https://www.codecademy.com/paths/create-a-back-end-app-with-javascript/tracks/bapi-javascript-objects-modules-and-browser-compatibility/modules/bapi-node-modules/projects/message-mixer-node](https://www.codecademy.com/paths/create-a-back-end-app-with-javascript/tracks/bapi-javascript-objects-modules-and-browser-compatibility/modules/bapi-node-modules/projects/message-mixer-node
I’m on step 11, and can’t quite get running the super-encoder.js program to work… I type ‘$ node super-encoder.js encode’ and get the prompt to enter the message I wish to encrypt.
Then when I type ‘hello world’, it returns undefined.
Can anyone spot why this may be? Thanks!
message-mixer.js:
// Import the functions from encryptors.js here.
const encryptors = require('./encryptors.js');
const { caesarCipher, symbolCipher, reverseCipher } = encryptors;
// User Input / Output Logic
/////////////////////////////////////////////
const encryptionMethod = getEncryptionMethod();
process.stdin.on('data', (userInput) => {
displayEncryptedMessage(encryptionMethod, userInput);
});
/* Helper function for determining which cipher method
the user chose when they ran the program. */
function getEncryptionMethod() {
let encryptionMethod;
const encryptionType = process.argv[2];
if (encryptionType === 'symbol') {
encryptionMethod = symbolCipher;
} else if (encryptionType === 'reverse') {
encryptionMethod = reverseCipher;
} else if (encryptionType === 'caesar') {
let amount = Number(process.argv[3]);
if (Number.isNaN(amount)) {
process.stdout.write(`Try again with a valid amount argument. \n`)
process.exit();
}
encryptionMethod = (str) => caesarCipher(str, amount);
}
else {
process.stdout.write(`Try again with a valid encryption type. \n`)
process.exit();
}
process.stdout.write('Enter the message you would like to encrypt...\n> ');
return encryptionMethod;
}
/* Helper function for displaying the encrypted message to the user. */
function displayEncryptedMessage(encryptionMethod, userInput) {
let str = userInput.toString().trim();
let output = encryptionMethod(str);
process.stdout.write(`\nHere is your encrypted message:\n> ${output}\n`)
process.exit();
}
encryptors.js:
// Declare and export the functions here.
const caesarCipher = (str, amount = 0) => {
if (amount < 0) {
return caesarCipher(str, amount + 26);
}
let output = '';
for (let i = 0; i < str.length; i++) {
let char = str[i];
if (char.match(/[a-z]/i)) {
let code = str.charCodeAt(i);
if (code >= 65 && code <= 90) {
char = String.fromCharCode(((code - 65 + amount) % 26) + 65);
} else if (code >= 97 && code <= 122) {
char = String.fromCharCode(((code - 97 + amount) % 26) + 97);
}
}
output += char;
}
return output;
};
const symbolCipher = (str) => {
const symbols = {
'i': '!',
'!': 'i',
'l': '1',
'1': 'l',
's': '$',
'$': 's',
'o': '0',
'0': 'o',
'a': '@',
'@': 'a',
'e': '3',
'3': 'e',
'b': '6',
'6': 'b'
}
let output = '';
for (let i = 0; i < str.length; i++) {
let char = str.toLowerCase()[i];
if (symbols[char]) {
output += symbols[char]
} else {
output += char;
}
}
return output;
};
const reverseCipher = (sentence) => {
let words = sentence.split(' ');
for (let i = 0; i < words.length; i++) {
words[i] = words[i].split('').reverse().join('');
}
return words.join(' ');
};
module.exports = {
caesarCipher,
symbolCipher,
reverseCipher
};
super-encoder.js:
// Import the encryptors functions here.
const encryptors = require('./encryptors.js');
const {caesarCipher, symbolCipher, reverseCipher} = encryptors;
const encodeMessage = (str) => {
// Use the encryptor functions here.
return
reverseCipher(symbolCipher(caesarCipher(str, 6)));
}
const decodeMessage = (str) => {
// Use the encryptor functions here.
return
caesarCipher(symbolCipher(reverseCipher(str)), -6);
}
// User input / output.
const handleInput = (userInput) => {
const str = userInput.toString().trim();
let output;
if (process.argv[2] === 'encode') {
output = encodeMessage(str);
}
if (process.argv[2] === 'decode') {
output = decodeMessage(str);
}
process.stdout.write(output + '\n');
process.exit();
}
// Run the program.
process.stdout.write('Enter the message you would like to encrypt...\n> ');
process.stdin.on('data', handleInput);
