import requests

##
# POST a request to the backend, and return a error
# response if any error occurs.
#
# @param endpoint the backend endpoint where to POST
#        this request.
# @param json the POST's body.
# @return the backend response (JSON format).
def backend_post(backend_url, endpoint, json):
    headers = {"Authorization": "ApiKey " + APIKEY}
    try:
        resp = requests.post(
            urljoin(backend_url, endpoint), json=json, headers=headers
        )
    except requests.ConnectionError:
        err_abort(500, message="Could not establish connection to backend")
    try:
        response_json = resp.json()
    except ValueError:
        err_abort(
            500,
            message="Could not parse response from backend",
            status_code=resp.status_code
        )
    if resp.status_code != 200:
        err_abort(
            500,
            message="Backend returned error status",
            json=response_json,
            status_code=resp.status_code
        )
    return response_json


##
# Issue a GET request to the backend.
#
# @param endpoint the backend endpoint where to issue the request.
# @param params (dict type of) URL parameters to append to the request.
# @return the JSON response from the backend, or a error response
#         if something unexpected happens.
def backend_get(backend_url, endpoint, params):
    headers = {"Authorization": "ApiKey " + APIKEY}
    try:
        resp = requests.get(
            urljoin(backend_url, endpoint), params=params, headers=headers
        )
    except requests.ConnectionError:
        err_abort(500, message="Could not establish connection to backend")
    try:
        response_json = resp.json()
    except ValueError:
        err_abort(500, message="Could not parse response from backend")
    if resp.status_code != 200:
        err_abort(
            500,
            message="Backend returned error status",
            json=response_json,
            status_code=resp.status_code
        )
    return response_json