import json as json_lib
import sys
import types
from socket import gethostname
from six.moves.urllib.parse import urlparse, urlunparse
import jwt
import requests
import six
from ...utilities.pyhocon import ConfigTree
from requests.auth import HTTPBasicAuth
from .callresult import CallResult
from .defs import ENV_VERBOSE, ENV_HOST, ENV_ACCESS_KEY, ENV_SECRET_KEY, ENV_WEB_HOST, ENV_FILES_HOST
from .request import Request, BatchRequest
from .token_manager import TokenManager
from ..config import load
from ..utils import get_http_session_with_retry, urllib_log_warning_setup
from ...version import __version__
class LoginError(Exception):
pass
class MaxRequestSizeError(Exception):
pass
class Session(TokenManager):
""" TRAINS API Session class. """
_AUTHORIZATION_HEADER = "Authorization"
_WORKER_HEADER = "X-Trains-Worker"
_ASYNC_HEADER = "X-Trains-Async"
_CLIENT_HEADER = "X-Trains-Client"
_async_status_code = 202
_session_requests = 0
_session_initial_timeout = (3.0, 10.)
_session_timeout = (10.0, 300.)
_write_session_data_size = 15000
_write_session_timeout = (300.0, 300.)
_sessions_created = 0
api_version = '2.1'
default_host = "https://demoapi.trains.allegro.ai"
default_web = "https://demoapp.trains.allegro.ai"
default_files = "https://demofiles.trains.allegro.ai"
default_key = "EGRTCO8JMSIGI6S39GTP43NFWXDQOW"
default_secret = "x!XTov_G-#vspE*Y(h$Anm&DIc5Ou-F)jsl$PdOyj5wG1&E!Z8"
# TODO: add requests.codes.gateway_timeout once we support async commits
_retry_codes = [
requests.codes.bad_gateway,
requests.codes.service_unavailable,
requests.codes.bandwidth_limit_exceeded,
requests.codes.too_many_requests,
]
@property
def access_key(self):
return self.__access_key
@property
def secret_key(self):
return self.__secret_key
@property
def host(self):
return self.__host
@property
def worker(self):
return self.__worker
def __init__(
self,
worker=None,
api_key=None,
secret_key=None,
host=None,
logger=None,
verbose=None,
initialize_logging=True,
client=None,
config=None,
http_retries_config=None,
**kwargs
):
if config is not None:
self.config = config
else:
self.config = load()
if initialize_logging:
self.config.initialize_logging()
token_expiration_threshold_sec = self.config.get(
"auth.token_expiration_threshold_sec", 60
)
super(Session, self).__init__(
token_expiration_threshold_sec=token_expiration_threshold_sec, **kwargs
)
self._verbose = verbose if verbose is not None else ENV_VERBOSE.get()
self._logger = logger
self.__access_key = api_key or ENV_ACCESS_KEY.get(
default=(self.config.get("api.credentials.access_key", None) or self.default_key)
)
if not self.access_key:
raise ValueError(
"Missing access_key. Please set in configuration file or pass in session init."
)
self.__secret_key = secret_key or ENV_SECRET_KEY.get(
default=(self.config.get("api.credentials.secret_key", None) or self.default_secret)
)
if not self.secret_key:
raise ValueError(
"Missing secret_key. Please set in configuration file or pass in session init."
)
host = host or self.get_api_server_host(config=self.config)
if not host:
raise ValueError("host is required in init or config")
self.__host = host.strip("/")
http_retries_config = http_retries_config or self.config.get(
"api.http.retries", ConfigTree()).as_plain_ordered_dict()
http_retries_config["status_forcelist"] = self._retry_codes
self.__http_session = get_http_session_with_retry(**http_retries_config)
self.__worker = worker or gethostname()
self.__max_req_size = self.config.get("api.http.max_req_size", None)
if not self.__max_req_size:
raise ValueError("missing max request size")
self.client = client or "api-{}".format(__version__)
self.refresh_token()
# update api version from server response
try:
token_dict = jwt.decode(self.token, verify=False)
api_version = token_dict.get('api_version')
if not api_version:
api_version = '2.2' if token_dict.get('env', '') == 'prod' else Session.api_version
Session.api_version = str(api_version)
except (jwt.DecodeError, ValueError):
pass
# now setup the session reporting, so one consecutive retries will show warning
# we do that here, so if we have problems authenticating, we see them immediately
# notice: this is across the board warning omission
urllib_log_warning_setup(total_retries=http_retries_config.get('total', 0), display_warning_after=3)
self.__class__._sessions_created += 1
def _send_request(
self,
service,
action,
version=None,
method="get",
headers=None,
auth=None,
data=None,
json=None,
refresh_token_if_unauthorized=True,
):
""" Internal implementation for making a raw API request.
- Constructs the api endpoint name
- Injects the worker id into the headers
- Allows custom authorization using a requests auth object
- Intercepts `Unauthorized` responses and automatically attempts to refresh the session token once in this
case (only once). This is done since permissions are embedded in the token, and addresses a case where
server-side permissions have changed but are not reflected in the current token. Refreshing the token will
generate a token with the updated permissions.
"""
host = self.host
headers = headers.copy() if headers else {}
headers[self._WORKER_HEADER] = self.worker
headers[self._CLIENT_HEADER] = self.client
token_refreshed_on_error = False
url = (
"{host}/v{version}/{service}.{action}"
if version
else "{host}/{service}.{action}"
).format(**locals())
while True:
if data and len(data) > self._write_session_data_size:
timeout = self._write_session_timeout
elif self._session_requests < 1:
timeout = self._session_initial_timeout
else:
timeout = self._session_timeout
res = self.__http_session.request(
method, url, headers=headers, auth=auth, data=data, json=json, timeout=timeout)
if (
refresh_token_if_unauthorized
and res.status_code == requests.codes.unauthorized
and not token_refreshed_on_error
):
# it seems we're unauthorized, so we'll try to refresh our token once in case permissions changed since
# the last time we got the token, and try again
self.refresh_token()
token_refreshed_on_error = True
# try again
continue
if (
res.status_code == requests.codes.service_unavailable
and self.config.get("api.http.wait_on_maintenance_forever", True)
):
self._logger.warning(
"Service unavailable: {} is undergoing maintenance, retrying...".format(
host
)
)
continue
break
self._session_requests += 1
return res
def add_auth_headers(self, headers):
headers[self._AUTHORIZATION_HEADER] = "Bearer {}".format(self.token)
return headers
def send_request(
self,
service,
action,
version=None,
method="get",
headers=None,
data=None,
json=None,
async_enable=False,
):
"""
Send a raw API request.
:param service: service name
:param action: action name
:param version: version number (default is the preconfigured api version)
:param method: method type (default is 'get')
:param headers: request headers (authorization and content type headers will be automatically added)
:param json: json to send in the request body (jsonable object or builtin types construct. if used,
content type will be application/json)
:param data: Dictionary, bytes, or file-like object to send in the request body
:param async_enable: whether request is asynchronous
:return: requests Response instance
"""
headers = self.add_auth_headers(
headers.copy() if headers else {}
)
if async_enable:
headers[self._ASYNC_HEADER] = "1"
return self._send_request(
service=service,
action=action,
version=version,
method=method,
headers=headers,
data=data,
json=json,
)
def send_request_batch(
self,
service,
action,
version=None,
headers=None,
data=None,
json=None,
method="get",
):
"""
Send a raw batch API request. Batch requests always use application/json-lines content type.
:param service: service name
:param action: action name
:param version: version number (default is the preconfigured api version)
:param headers: request headers (authorization and content type headers will be automatically added)
:param json: iterable of json items (batched items, jsonable objects or builtin types constructs). These will
be sent as a multi-line payload in the request body.
:param data: iterable of bytes objects (batched items). These will be sent as a multi-line payload in the
request body.
:param method: HTTP method
:return: requests Response instance
"""
if not all(
isinstance(x, (list, tuple, type(None), types.GeneratorType))
for x in (data, json)
):
raise ValueError("Expecting list, tuple or generator in 'data' or 'json'")
if not data and not json:
raise ValueError(
"Missing data (data or json), batch requests are meaningless without it."
)
headers = headers.copy() if headers else {}
headers["Content-Type"] = "application/json-lines"
if data:
req_data = "\n".join(data)
else:
req_data = "\n".join(json_lib.dumps(x) for x in json)
cur = 0
results = []
while True:
size = self.__max_req_size
slice = req_data[cur: cur + size]
if not slice:
break
if len(slice) < size:
# this is the remainder, no need to search for newline
pass
elif slice[-1] != "\n":
# search for the last newline in order to send a coherent request
size = slice.rfind("\n") + 1
# readjust the slice
slice = req_data[cur: cur + size]
if not slice:
raise MaxRequestSizeError('Error: {}.{} request exceeds limit {} > {} bytes'.format(
service, action, len(req_data), self.__max_req_size))
res = self.send_request(
method=method,
service=service,
action=action,
data=slice,
headers=headers,
version=version,
)
results.append(res)
if res.status_code != requests.codes.ok:
break
cur += size
return results
def validate_request(self, req_obj):
""" Validate an API request against the current version and the request's schema """
try:
# make sure we're using a compatible version for this request
# validate the request (checks required fields and specific field version restrictions)
validate = req_obj.validate
except AttributeError:
raise TypeError(
'"req_obj" parameter must be an backend_api.session.Request object'
)
validate()
def send_async(self, req_obj):
"""
Asynchronously sends an API request using a request object.
:param req_obj: The request object
:type req_obj: Request
:return: CallResult object containing the raw response, response metadata and parsed response object.
"""
return self.send(req_obj=req_obj, async_enable=True)
def send(self, req_obj, async_enable=False, headers=None):
"""
Sends an API request using a request object.
:param req_obj: The request object
:type req_obj: Request
:param async_enable: Request this method be executed in an asynchronous manner
:param headers: Additional headers to send with request
:return: CallResult object containing the raw response, response metadata and parsed response object.
"""
self.validate_request(req_obj)
if isinstance(req_obj, BatchRequest):
# TODO: support async for batch requests as well
if async_enable:
raise NotImplementedError(
"Async behavior is currently not implemented for batch requests"
)
json_data = req_obj.get_json()
res = self.send_request_batch(
service=req_obj._service,
action=req_obj._action,
version=req_obj._version,
json=json_data,
method=req_obj._method,
headers=headers,
)
# TODO: handle multiple results in this case
try:
res = next(r for r in res if r.status_code != 200)
except StopIteration:
# all are 200
res = res[0]
else:
res = self.send_request(
service=req_obj._service,
action=req_obj._action,
version=req_obj._version,
json=req_obj.to_dict(),
method=req_obj._method,
async_enable=async_enable,
headers=headers,
)
call_result = CallResult.from_result(
res=res,
request_cls=req_obj.__class__,
logger=self._logger,
service=req_obj._service,
action=req_obj._action,
session=self,
)
return call_result
@classmethod
def get_api_server_host(cls, config=None):
if not config:
from ...config import config_obj
config = config_obj
return ENV_HOST.get(default=(config.get("api.api_server", None) or
config.get("api.host", None) or cls.default_host)).rstrip('/')
@classmethod
def get_app_server_host(cls, config=None):
if not config:
from ...config import config_obj
config = config_obj
# get from config/environment
web_host = ENV_WEB_HOST.get(default=config.get("api.web_server", "")).rstrip('/')
if web_host:
return web_host
# return default
host = cls.get_api_server_host(config)
if host == cls.default_host and cls.default_web:
return cls.default_web
# compose ourselves
if '://demoapi.' in host:
return host.replace('://demoapi.', '://demoapp.', 1)
if '://api.' in host:
return host.replace('://api.', '://app.', 1)
parsed = urlparse(host)
if parsed.port == 8008:
return host.replace(':8008', ':8080', 1)
raise ValueError('Could not detect TRAINS web application server')
@classmethod
def get_files_server_host(cls, config=None):
if not config:
from ...config import config_obj
config = config_obj
# get from config/environment
files_host = ENV_FILES_HOST.get(default=(config.get("api.files_server", ""))).rstrip('/')
if files_host:
return files_host
# return default
host = cls.get_api_server_host(config)
if host == cls.default_host and cls.default_files:
return cls.default_files
# compose ourselves
app_host = cls.get_app_server_host(config)
parsed = urlparse(app_host)
if parsed.port:
parsed = parsed._replace(netloc=parsed.netloc.replace(':%d' % parsed.port, ':8081', 1))
elif parsed.netloc.startswith('demoapp.'):
parsed = parsed._replace(netloc=parsed.netloc.replace('demoapp.', 'demofiles.', 1))
elif parsed.netloc.startswith('app.'):
parsed = parsed._replace(netloc=parsed.netloc.replace('app.', 'files.', 1))
else:
parsed = parsed._replace(netloc=parsed.netloc + ':8081')
return urlunparse(parsed)
@classmethod
def check_min_api_version(cls, min_api_version):
"""
Return True if Session.api_version is greater or equal >= to min_api_version
"""
def version_tuple(v):
v = tuple(map(int, (v.split("."))))
return v + (0,) * max(0, 3 - len(v))
# If no session was created, create a default one, in order to get the backend api version.
if cls._sessions_created <= 0:
try:
dummy = cls()
except Exception:
pass
return version_tuple(cls.api_version) >= version_tuple(str(min_api_version))
def _do_refresh_token(self, old_token, exp=None):
""" TokenManager abstract method implementation.
Here we ignore the old token and simply obtain a new token.
"""
verbose = self._verbose and self._logger
if verbose:
self._logger.info(
"Refreshing token from {} (access_key={}, exp={})".format(
self.host, self.access_key, exp
)
)
auth = HTTPBasicAuth(self.access_key, self.secret_key)
res = None
try:
data = {"expiration_sec": exp} if exp else {}
res = self._send_request(
service="auth",
action="login",
auth=auth,
json=data,
refresh_token_if_unauthorized=False,
)
try:
resp = res.json()
except ValueError:
resp = {}
if res.status_code != 200:
msg = resp.get("meta", {}).get("result_msg", res.reason)
raise LoginError(
"Failed getting token (error {} from {}): {}".format(
res.status_code, self.host, msg
)
)
if verbose:
self._logger.info("Received new token")
return resp["data"]["token"]
except LoginError:
six.reraise(*sys.exc_info())
except KeyError as ex:
# check if this is a misconfigured api server (getting 200 without the data section)
if res and res.status_code == 200:
raise ValueError('It seems *api_server* is misconfigured. '
'Is this the TRAINS API server {} ?'.format(self.host))
else:
raise LoginError("Response data mismatch: No 'token' in 'data' value from res, receive : {}, "
"exception: {}".format(res, ex))
except Exception as ex:
raise LoginError('Unrecognized Authentication Error: {} {}'.format(type(ex), ex))
def __str__(self):
return "{self.__class__.__name__}[{self.host}, {self.access_key}/{secret_key}]".format(
self=self, secret_key=self.secret_key[:5] + "*" * (len(self.secret_key) - 5)
)