The right way to retailer keys in env recordsdata?

Utilizing the Setting in Vapor 4

Similar to many standard server facet frameworks, your Vapor based mostly backend software can load a file referred to as .env. It’s potential to retailer key-value based mostly (secret) configuration values inside this file. If you run the app, one of many following file might be loaded, based mostly on the present setting:

• Manufacturing (.env)
• Growth (.env.improvement)
• Testing (.env.testing)

If you execute your exams the .env.testing file might be used. If you happen to begin the app utilizing the serve Vapor command you can too change the setting utilizing the --env or -e flag. The accessible choices are manufacturing and improvement, and the corresponding .env file might be loaded. It’s potential to create a customized setting, you may learn extra about this within the official Vapor docs. The .env file often accommodates one key and worth per line, now the issue begins once you need to retailer a multiline secret key within the file. So what can we do about this? 🤔

Base64 encoded secret keys

Sure, we are able to encode the key key utilizing a base64 encoding. No, I do not need to copy my secrets and techniques into an on-line base64 encoder, as a result of there’s a fairly easy shell command that I can use.

echo "<my-secret-key>" | base64

If you happen to do not like unix instructions, we are able to all the time put collectively just a little Swift script and use an extension on the String sort to encode keys. Simply save the snippet from under right into a base64.swift file, put your key into the important thing part, give the file some executable permission & run it utilizing the chmod o+x && ./base64.swift one-liner command and voilá…

#! /usr/bin/swift

import Basis

extension String {

    func base64Encoded() -> String? {
        return information(utilizing: .utf8)?.base64EncodedString()
    }
}

let key = """
    <my-secret-key-comes-here>
"""

print(key.base64Encoded()!)

You’ll be able to copy & paste the encoded worth of the key key into your individual .env.* file, exchange the asterix image together with your present setting in fact, earlier than you do it. 🙈

//e.g. .env.improvement
SECRET_KEY="<base64-encoded-secret-key>"

Now we simply need to decode this key in some way, earlier than we are able to begin utilizing it…

Decoding the key key

You’ll be able to implement a base64 decoder as a String extension with just some strains of Swift code.

import Basis

extension String {

    func base64Decoded() -> String? {
        guard let information = Information(base64Encoded: self) else { return nil }
        return String(information: information, encoding: .utf8)
    }
}

Now in my tasks I like to increase the Setting object and place all my customized variables there as static constants, this manner I can entry them in a extremely handy manner, plus if one thing goes mistaken (often after I do not re-create the .env file after a git reset or I haven’t got all of the variables current within the dotenv file) the app will crash due to the pressured unwraps, and I am going to know for certain that one thing is mistaken with my setting. It is a crash for my very own security. 💥

import Vapor

extension Setting {
    static let secretKey = Self.get("SECRET_KEY")!.base64Decoded()!
}


Setting.secretKey

I feel this strategy may be very helpful. In fact it’s best to place the .env.* sample into your .gitignore file, in any other case should you place some secrets and techniques into the dotenv file and also you push that into the distant… nicely, everybody else will know your keys, passwords, and so on. You do not need that, proper? ⚠️

Be happy to make use of this technique when it’s important to implement a Register With Apple workflow, or a Apple Push Notification service (APNs). In these circumstances you will positively need to cross one ore extra secret keys to your Vapor based mostly backend software. That is it for now, thanks for studying.