webapi.py

#!/usr/bin/env python
# vim: set fileencoding=utf-8 :

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import requests
import simplejson as json

from urllib.parse import urlparse


class WebAPIError(RuntimeError):
    def __init__(self, cmd, url, answer):
        message = "{cmd} error {status}: {url}\nError:{text}".format(
            cmd=cmd, status=answer.status_code, url=url, text=answer.text
        )
        super().__init__(message)


class WebAPI(object):
    """Central class for all remote service related calls"""

    API_VERSION = "v1"
    API_PATH = "/api/{}".format(API_VERSION)

    def __init__(self, platform, user, token=None):
        self.platform = platform
        self.parsed = urlparse(self.platform)
        self.user = "**anonymous**" if token is None else user
        self.token = token

    def is_anonymous(self):
        return self.token is None

    def __enter__(self):
        return self

    def __exit__(self, *exc):
        return

    def _make_headers(self):
        if self.token is None:
            return None

        return {
            "Authorization": "Token %s" % (self.token),
            "Content-Type": "application/json",
        }

    def __build_url(self, path):
        platform = self.parsed.geturl()
        if platform.endswith("/"):
            platform = platform[:-1]

        if path.startswith("/"):
            path = path[1:]

        url = "{platform}/{path}".format(platform=platform, path=path)
        return url

    def get(self, path):
        url = self.__build_url(path)
        answer = requests.get(url, headers=self._make_headers())

        # if answer.status_code < 200 or answer.status_code >= 300:
        if answer.status_code not in [200, 204]:
            raise WebAPIError("GET", url, answer)

        return answer.json()

    def post(self, path, data=None):
        url = self.__build_url(path)
        answer = requests.post(url, json=data, headers=self._make_headers())

        if answer.status_code not in [200, 201]:
            raise WebAPIError("POST", url, answer)

        try:
            return answer.json()
        except json.JSONDecodeError:
            return answer.text

    def put(self, path, data=None):
        url = self.__build_url(path)
        answer = requests.put(url, json=data, headers=self._make_headers())

        if answer.status_code not in [200, 204]:
            raise WebAPIError("PUT", url, answer)

        try:
            return answer.json()
        except json.JSONDecodeError:
            return answer.text

    def delete(self, path):
        url = self.__build_url(path)
        answer = requests.delete(url, headers=self._make_headers())

        # Should respond a 204 status and an empty body
        if answer.status_code not in [200, 204]:
            raise WebAPIError("DELETE", url, answer)