old_contents: # Copyright 2017 Jonathan Anderson
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  # 1. Redistributions of source code must retain the above copyright notice, this
  # list of conditions and the following disclaimer.
  #
  # 2. Redistributions in binary form must reproduce the above copyright notice,
  # this list of conditions and the following disclaimer in the documentation
  # and/or other materials provided with the distribution.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  import base64
  import config
  import hashlib
  import hmac as hm
  import os
  
  secret = os.environ.get("SECRET_KEY")
  if secret is None:
      import random, warnings
      warnings.warn(
          'No SECRET_KEY in .env or environment; generating one-time key\n')
  
      secret = random.getrandbits(128)
  
  else:
      secret = hashlib.sha512(secret).digest()
  
  def hmac(text):
      assert type(text) == str
      assert len(text) > 0
  
      h = hm.new(secret, text, hashlib.sha512)
      return base64.b32encode(h.digest()).lower()[:20]
  
  def verify(text, mac):
      return (mac == hmac(text))
  
new_contents: # Copyright 2017 Jonathan Anderson
  #
  # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  # 1. Redistributions of source code must retain the above copyright notice, this
  # list of conditions and the following disclaimer.
  #
  # 2. Redistributions in binary form must reproduce the above copyright notice,
  # this list of conditions and the following disclaimer in the documentation
  # and/or other materials provided with the distribution.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  # DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  # FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  import base64
  import config
  import hashlib
  import hmac as hm
  import os
  
  secret = os.environ.get("SECRET_KEY")
  if secret is None:
      import random, string, warnings
      warnings.warn(
          'No SECRET_KEY in .env or environment; generating one-time key\n')
  
      secret = ''.join(
              random.SystemRandom()
                    .choice(string.ascii_uppercase + string.digits)
              for _ in range(20)
      )
  
  else:
      secret = hashlib.sha512(secret).digest()
  
  def hmac(text):
      assert type(text) == str
      assert len(text) > 0
  
      h = hm.new(secret, text, hashlib.sha512)
      return base64.b32encode(h.digest()).lower()[:20]
  
  def verify(text, mac):
      return (mac == hmac(text))
  
subject: Fix random secret key generation.