HTTPRequestor.py

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# Copyright (c) 2024 Martin Schobert, Pentagrid AG
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from typing import Dict

import requests
from requests.adapters import HTTPAdapter
from urllib3 import Retry

class HTTPRequestor():

    def __init__(self):
        """
        Create a new downloaer, which keeps tracks of temporarily server errors.
        """
        retry_strategy = Retry(
            total=5,
            backoff_factor=1,
            status_forcelist=[429, 500, 502, 503, 504],
            respect_retry_after_header=True
        )
        adapter = HTTPAdapter(max_retries=retry_strategy)
        self.http = requests.Session()
        self.http.mount("https://", adapter)
        self.http.mount("http://", adapter)

    def _get(self, url: str, params: Dict[str, object]) -> requests.Response:
        """
        Internal helper for send GET requests.
        :param url: The URL to download.
        :param params: Parameters to pass to Request.get.
        :return: Returns a Response object.
        """
        r = self.http.get(url, params=params)

        if r.status_code != 200:
            raise RuntimeError(f"Failed to download certificate. HTTP status code is {r.status_code}.")

        return r

    def get(self, url: str, params: Dict[str, object]) -> bytes:
        """
        Wrapper for GET requests to an URL with parameters. Gets the content as bytes.
        :param url: The URL to download.
        :param params: Parameters to pass to Request.get.
        :return: Returns the reponse as bytes.
        """
        return self._get(url, params).content

    def get_json(self, url: str, params: Dict[str, object]) -> Dict[str, object]:
        """
        Wrapper for GET requests to an URL with parameters. Gets the content as JSON.
        :param url: The URL to download.
        :param params: Parameters to pass to Request.get.
        :return: Returns the reponse as JSON.
        """
        return self._get(url, params).json()