RestAPIUtils.kt

val secret = HMAC_SECRET
var keySpec: SecretKeySpec
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val obfuscatedSecretData = Base64.decode(secret, Base64.DEFAULT)
val shipFastAPIKeyData = loadShipFastAPIKey(context).toByteArray(Charsets.UTF_8)
for (i in 0 until minOf(obfuscatedSecretData.size, shipFastAPIKeyData.size)) {
  obfuscatedSecretData[i] = (obfuscatedSecretData[i].toInt() xor shipFastAPIKeyData[i].toInt()).toByte()
}
val obfuscatedSecret = Base64.encode(obfuscatedSecretData, Base64.DEFAULT)
keySpec = SecretKeySpec(Base64.decode(obfuscatedSecret, Base64.DEFAULT), "HmacSHA256")
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// Compute the request HMAC using the HMAC SHA-256 algorithm
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