webapp/backend/zeiterfassung.py

   1 #!/usr/bin/python
   2
   3 import hashlib
   4 import hmac
   5 import json
   6 import tornado.httpclient
   7 import tornado.gen
   8 import urllib
   9 import urlparse
  10
  11 from misc import Object
  12
  13 class ZeiterfassungClient(Object):
  14         algorithm = "Zeiterfassung-HMAC-SHA512"
  15
  16         def init(self):
  17                 self.url = self.settings.get("zeiterfassung_url")
  18
  19                 # API credentials
  20                 self.api_key    = self.settings.get("zeiterfassung_api_key")
  21                 self.api_secret = self.settings.get("zeiterfassung_api_secret")
  22
  23                 # Check if all configuration values are set
  24                 if not all((self.url, self.api_key, self.api_secret)):
  25                         raise RuntimeError("%s is not configured" % self.__class__.__name__)
  26
  27                 # Create HTTPClient
  28                 self.http_client = tornado.httpclient.AsyncHTTPClient(
  29                         defaults = {
  30                                 "User-Agent" : "IPFireWebApp",
  31                         }
  32                 )
  33
  34         def _make_signature(self, method, path, body):
  35                 # Empty since we only support POST
  36                 canonical_query = ""
  37
  38                 # Put everything together
  39                 string_to_sign = "\n".join((
  40                         method, path, canonical_query,
  41                 )).encode("utf-8") + body
  42
  43                 # Compute HMAC
  44                 h = hmac.new(self.api_secret.encode("utf-8"), string_to_sign, hashlib.sha512)
  45
  46                 return h.hexdigest()
  47
  48         @tornado.gen.coroutine
  49         def send_request(self, path, **kwargs):
  50                 url = urlparse.urljoin(self.url, path)
  51
  52                 # Query arguments are all keyword arguments
  53                 arguments = kwargs
  54
  55                 request = tornado.httpclient.HTTPRequest(url, method="POST")
  56                 request.body = urllib.urlencode(arguments)
  57
  58                 # Compose the signature
  59                 signature = self._make_signature("POST", path, request.body)
  60
  61                 # Add authorization header
  62                 request.headers["Authorization"] = " ".join(
  63                         (self.algorithm, self.api_key, signature)
  64                 )
  65
  66                 # Send the request
  67                 response = yield self.http_client.fetch(request)
  68
  69                 # Decode the JSON response
  70                 d = json.loads(response.body.decode())
  71
  72                 raise tornado.gen.Return(d)