import hmac
import json
import hashlib
import urllib
import urllib2
from urlparse import urljoin, urlparse
from datetime import datetime
from tg.controllers.util import smart_str
from formencode import variabledecode
log = logging.getLogger(__name__)
class RestClient(object):
def __init__(self, api_key, secret_key, base_uri,
http_username=None, http_password=None):
self._api_key = api_key
self._secret_key = secret_key
self.base_uri = base_uri
self.Request = self._request_class()
self.RedirectHandler = self._redirect_handler_class()
redirect_handler = self.RedirectHandler()
if http_username:
pw_mgr = urllib2.HTTPPasswordMgrWithDefaultRealm()
pw_mgr.add_password(None, base_uri, http_username, http_password)
auth_handler = urllib2.HTTPBasicAuthHandler(pw_mgr)
self._opener = urllib2.build_opener(redirect_handler, auth_handler)
else:
self._opener = urllib2.build_opener(redirect_handler)
def sign_request(self, path, params):
if hasattr(params, 'items'): params = params.items()
has_api_key = has_api_timestamp = has_api_signature = False
for k,v in params:
if k == 'api_key': has_api_key = True
if k == 'api_timestamp': has_api_timestamp = True
if k == 'api_signature': has_api_signature = True
if not has_api_key: params.append(('api_key', self._api_key))
if not has_api_timestamp:
params.append(('api_timestamp', datetime.utcnow().isoformat()))
if not has_api_signature:
string_to_sign = path + '?' + urlencode(sorted(params))
digest = hmac.new(self._secret_key, string_to_sign, hashlib.sha256)
params.append(('api_signature', digest.hexdigest()))
return params
def request(self, method, path, **params):
req = self.Request(method, path, params)
fp = self._opener.open(req)
return json.loads(fp.read())
def _redirect_handler_class(self):
client = self
class RedirectHandler(urllib2.HTTPRedirectHandler):
def redirect_request(self, req, fp, code, msg, headers, newurl):
m = req.get_method()
if (code in (301, 302, 303, 307) and m in ("GET", "HEAD")
or code in (301, 302, 303) and m == "POST"):
newurl = newurl.replace(' ', '%20')
newheaders = dict((k,v) for k,v in req.headers.items()
if k.lower() not in ("content-length", "content-type")
)
result = urlparse(newurl)
log.debug('Redirect to %s' % result.path)
return client.Request(
'GET', result.path,
headers=newheaders,
origin_req_host=req.get_origin_req_host(),
unverifiable=True)
else:
raise urllib2.HTTPError(req.get_full_url(), code, msg, headers, fp)
return RedirectHandler
def _request_class(self):
client = self
class Request(urllib2.Request):
def __init__(self, method, path, params=None, **kwargs):
if params is None: params = {}
params = variabledecode.variable_encode(params, add_repetitions=False)
params = client.sign_request(path, params)
self._method = method.upper()
if self._method == 'GET':
url = urljoin(client.base_uri, path) + '?' + urlencode(params)
data=None
else:
url = urljoin(client.base_uri, path)
data=urlencode(params)
urllib2.Request.__init__(self, url, data=data, **kwargs)
def get_method(self):
return self._method
return Request
def generate_smart_str(params):
if isinstance(params, dict): iterparams = params.iteritems()
else: iterparams = iter(params)
for key, value in iterparams:
if value is None: continue
if isinstance(value, (list, tuple)):
for item in value:
yield smart_str(key), smart_str(item)
else:
yield smart_str(key), smart_str(value)
def urlencode(params):
"""
A version of Python's urllib.urlencode() function that can operate on
unicode strings. The parameters are first case to UTF-8 encoded strings and
then encoded as per normal.
"""
return urllib.urlencode([i for i in generate_smart_str(params)])