cloud-init-cherrypy/main.py

import os
import sys

import cherrypy
from cherrypy.lib.static import serve_file
import yaml
import socket

import configparser

PATH = os.path.dirname(os.path.abspath(__file__))

config = configparser.ConfigParser()
config.read("config.ini")

user_data_filename = config["app"].get("user_data", "sample_file.txt")
meta_data_filename = config["app"].get("meta_data", "meta_data_extra.txt")


class MainApp:
    def __init__(self, *args):
        self._init_ip()

    def _init_ip(self):
        """
        Get remote IP
        """
        try:
            self.remoteip = cherrypy.request.headers.get(
                'X-Real-Ip',
                cherrypy.request.remote.ip
            )
        except:
            self.remoteip = cherrypy.request.remote.ip

        self.hostinfo = socket.gethostbyaddr(self.remoteip)

    @cherrypy.expose
    def user_data(self):
        """
        Serves a static file
        """
        filepath = os.path.join(PATH, "data", user_data_filename)
        return serve_file(filepath, "application/x-download", "attachment")

    @cherrypy.expose
    def meta_data(self):
        """
        Return meta-data in YAML
        """
        hostname =self.hostinfo[0]
        data = {"instance-id": hostname.split(".")[0], "local-hostname": hostname}

        filepath = os.path.join(PATH, "data", hostname, meta_data_filename)
        if os.path.exists(filepath):
            with open(filepath, "r") as f:
                line = f.readlines()[0]
                ls = list(map(lambda k: k.strip(), line.split(":")))
                data[ls[0]] = ls[1]

        return yaml.dump(data)

    @cherrypy.expose
    def finished(self, data):
        """
        Saves additional meta-data

        :param data: meta-data to be added
        """
        folder = os.path.join(PATH, "data", self.hostinfo[0])
        if not os.path.exists(folder):
            os.makedirs(folder)

        with open(os.path.join(folder, meta_data_filename), "w") as f:
            f.write(data)


ROOT = MainApp()

if __name__ == "__main__":
    cherrypy.server.socket_host = config["server"].get("server_host", "127.0.0.1")
    cherrypy.server.socket_port = config["server"].getint("server_port", 8081)
    ENGINE = cherrypy.engine

    cherrypy.tree.mount(ROOT)
    if hasattr(ENGINE, "signal_handler"):
        ENGINE.signal_handler.subscribe()
    if hasattr(ENGINE, "console_control_handler"):
        ENGINE.console_control_handler.subscribe()
    try:
        ENGINE.start()
    except Exception:
        sys.exit(1)
    else:
        ENGINE.block()