Problem starting Sidekiq in development

If you ever get this error:

can't link outside actor context

Followed by something like:

    /Library/Ruby/Gems/2.0.0/gems/celluloid-0.16.0/lib/celluloid.rb:176:in `new_link'
    /Library/Ruby/Gems/2.0.0/gems/sidekiq-3.3.4/lib/sidekiq/launcher.rb:21:in `initialize'
    /Library/Ruby/Gems/2.0.0/gems/sidekiq-3.3.4/lib/sidekiq/cli.rb:81:in `new'
    /Library/Ruby/Gems/2.0.0/gems/sidekiq-3.3.4/lib/sidekiq/cli.rb:81:in `run'
    /Library/Ruby/Gems/2.0.0/gems/sidekiq-3.3.4/bin/sidekiq:8:in `<top (required)>'
    /Library/Ruby/Gems/2.0.0/bin/sidekiq:23:in `load'
    /Library/Ruby/Gems/2.0.0/bin/sidekiq:23:in `<main>'

It's mostly likely somehow related with either ZenTest or another testing framework. 

In my case, i was adding the ZenTest gem both in the development and test groups of my Gemfile. Moving it away from the development group solved the problem.

AES encryption in Ruby and Decryption in Java

This one is precious, as it took me a long time to figure out. As a side-note, Java apparently only supports 128bit AES.

Here's the Ruby code:

def encrypt(string, pwd)
    salt = OpenSSL::Random.random_bytes(16)

    # prepare cipher for encryption
    e ='AES-128-CBC')

    # next, generate a PKCS5-based string for your key + initialization vector
    key_iv = OpenSSL::PKCS5.pbkdf2_hmac_sha1(pwd, salt, 1024, e.key_len+e.iv_len)
    key = key_iv[0, e.key_len]
    iv  = key_iv[e.key_len, e.iv_len]

    # now set the key and iv for the encrypting cipher
    e.key = key
    e.iv  = iv

    # encrypt the data!
    encrypted = '' << e.update(string) <<
    [encrypted, iv, salt].map {|v| ::Base64.strict_encode64(v)}.join("--")   

And the Java part:

public static String decrypt(String encrypted, String pwd) throws Exception {

        String[] parts = encrypted.split("--");
        if (parts.length != 3) return null;

        byte[] encryptedData = Base64.decodeBase64(parts[0]);
        byte[] iv = Base64.decodeBase64(parts[1]);
        byte[] salt = Base64.decodeBase64(parts[2]);

        SecretKeyFactory factory = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
        KeySpec spec = new PBEKeySpec(pwd.toCharArray(), salt, 1024, 128);
        SecretKey tmp = factory.generateSecret(spec);
        SecretKey aesKey = new SecretKeySpec(tmp.getEncoded(), "AES");

        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
        cipher.init(Cipher.DECRYPT_MODE, aesKey, new IvParameterSpec(iv));

        byte[] result = cipher.doFinal(encryptedData);
        return new String(result, "UTF-8");