geomon/gschliefgraben_glasfaser/my_api.py

'''
Python version: 3.7
https://www.mybluelinux.com/python-how-to-refresh-an-jwt-access-token-using-decorators/
https://stackoverflow.com/questions/37094419/python-requests-retry-request-after-re-authentication
'''

import string
import time
import os
import requests


class MyApi():
    """ MyApi class """
    host = None
    key = None
    secret = None
    access_token = None
    access_token_expiration = None

    def __init__(self, host):
        # the function that is executed when
        # an instance of the class is created
        self.host = host
        # self.key = key
        # self.secret = secret

        try:
            self._session = requests.Session()  # Session for tokens
            self.access_token = self.authenticate()
            if self.access_token is None:
                raise Exception("Request for access token failed.")
            else:
                self.session = requests.Session()  # Authenticated session
                self.session.headers["Authorization"] = "Bearer " + \
                    self.access_token
                self.session.hooks['response'].append(self.reauth)
                self.access_token_expiration = time.time() + 3600
        except requests.exceptions.HTTPError as errh:
            print("Http Error:", errh)
        except requests.exceptions.ConnectionError as errc:
            print("Error Connecting:", errc)
        except requests.exceptions.Timeout as errt:
            print("Timeout Error:", errt)
        except requests.exceptions.RequestException as err:
            print("OOps: Something Else", err)

    def reauth(self, res, *args, **kwargs):
        """Hook to re-authenticate whenever authentication expires."""
        if res.status_code == requests.codes['unauthorized']:
            if res.request.headers.get('REATTEMPT'):
                res.raise_for_status()
            # self.refresh_auth()
            req = res.request
            req.headers['REATTEMPT'] = 1
            # req = self.session.auth(req)
            res = self.session.send(req)
            return res

    # def refresh_auth(self):
    #     """Use the refresh token to get a new access token."""
    #     res = self._session.post(self.abs_url(
    #         "api/token/refresh/"), data={"refresh": self.refresh})
    #     if res.status_code == 200:
    #         self.access_token = res.json()['access_token']
        # else:
        #     # Token expired -> re-authenticate
    def getSensorData(self, sensor: string, date_start, date_end):
        ''' request observations'''
        try:
            request = self.session.get('https://api.dgnss-sensors.com/gschliefgraben?sensors=(\''+sensor+ '\')&start=' + date_start+ '&end=' + date_end,
                                       headers={
                                           'cache-control': 'no-cache',
                                           'Content-Type': 'application/x-www-form-urlencoded',
                                           'accept': 'application/json'
                                       },
                                       data="grant_type=client_credentials&scope=gschliefgraben"
                                       )
            # optional: raise exception for status code
            request.raise_for_status()
        except requests.exceptions.HTTPError as err:
            print(err)
            return None
        else:
            # assuming the response's structure is
            # {"access_token": ""}
            data = request.json()
            return data

    def authenticate(self):
        ''' the function that is
        # used to request the JWT '''
        try:
            # build the JWT and store
            # in the variable `token_body`
            refresh_token = os.environ.get("REFRESH_TOKEN")

            # request an access token
            request = requests.post(self.host,
                                    headers={
                                        'Authorization': 'Basic ' + refresh_token,
                                        'cache-control': 'no-cache',
                                        'Content-Type': 'application/x-www-form-urlencoded',
                                        'accept': 'application/json'
                                    },
                                    data='grant_type=client_credentials&scope=gschliefgraben')

            # optional: raise exception for status code
            request.raise_for_status()
        except requests.exceptions.HTTPError as err:
            print(err)
            return None
        else:
            # assuming the response's structure is
            # {"access_token": ""}
            data = request.json()
            access_token_expire = time.time() + int(data['expires_in'])
            return data['access_token']