app.py

import os
import requests
from config import config
from flask_cors import CORS
from urllib.parse import parse_qsl
from exceptions import APIException
from flask import Flask, jsonify
import markdown
import markdown.extensions.fenced_code
import markdown.extensions.codehilite
from pygments.formatters import HtmlFormatter

app = Flask(__name__)
CORS(app)


@app.route("/")
def index():
    readme_file = open("README.md", "r")
    md_template_string = markdown.markdown(
        readme_file.read(), extensions=["fenced_code", "codehilite"]
    )

    # Generate css for syntax highlighting
    formatter = HtmlFormatter(style="emacs", full=True, cssclass="codehilite")
    css_string = formatter.get_style_defs()
    md_css_string = "<style>" + css_string + "</style>"

    md_template = md_css_string + md_template_string
    return md_template


@app.route("/authenticate/<code>", methods=["GET"])
def authenticate(code):
    creds = get_access_token(*build_config(code))
    return jsonify(creds)


def build_config(code):
    url = config["oauth_url"]
    headers = {"Content-Type": "application/json"}
    payload = {
        "client_id": os.environ.get(config["oauth_client_id"]),
        "client_secret": os.environ.get(config["oauth_client_secret"]),
        "code": code,
    }

    # Raise exceptions if client_id or client_secret not found.
    if not payload["client_id"]:
        raise APIException("Client Id is not found in environment", status_code=422)
    if not payload["client_secret"]:
        raise APIException("Client secret is not found in environment", status_code=422)
    return url, headers, payload


def get_access_token(url, headers, payload):
    response = requests.post(url, headers=headers, params=payload)
    # If client id not found
    if response.text == "Not Found":
        raise APIException("Client id is invalid", status_code=404)
    qs = dict(parse_qsl(response.text))
    creds = {item: qs[item] for item in qs}
    return creds


# Global error handler
@app.errorhandler(APIException)
def handle_api_exception(error):
    response = jsonify({"error": error.to_dict()})
    response.status_code = error.status_code
    return response


if __name__ == "__main__":
    app.run()