# encoding: utf-8
from typing import Optional, Awaitable
from prometheus_client import Gauge
from prometheus_client.core import CollectorRegistry
from prometheus_client.exposition import choose_encoder
import tornado.ioloop
import tornado.web
import os
import tornado.gen
from datetime import datetime
from kubernetes import client
import urllib3

urllib3.disable_warnings(urllib3.exceptions.InsecureRequestWarning)
api_token = os.getenv('API_TOKEN')
api_addr = os.getenv('API_ADDR')
namespace = os.getenv('NAMESPACE')


def date_time_to_date(date):
    """
    专门给k8s api使用 获取到的时间对象+8小时后转换为日期字符串
    :param date:<class 'datetime.datetime'> 2022-06-29 04:13:33+00:00
    :return:  2022-06-29 04:13:33+00:00 +8 小时并且 转换 str
    """
    from datetime import timedelta, datetime
    new_data = date + timedelta(hours=8)
    new_data = datetime.strftime(new_data, '%Y-%m-%d %H:%M')
    return new_data


def list_namespaced_deployment(api_addr, api_token, namespace):
    """
    获取连接
    :return: conn
    """
    configuration = client.Configuration()
    setattr(configuration, 'verify_ssl', False)
    client.Configuration.set_default(configuration)
    configuration.host = api_addr
    configuration.verify_ssl = False
    configuration.debug = False
    configuration.api_key = {"authorization": "Bearer " + api_token}
    conn = client.Configuration.set_default(configuration)
    _api_client = client.AppsV1Api(api_client=conn)
    req = _api_client.list_namespaced_deployment(namespace).items
    deployment_list = []
    for i in req:
        create_time = date_time_to_date(i.metadata.creation_timestamp)
        ns = {
            "name": i.metadata.name,
            "image": i.spec.template.spec.containers[0].image,
            "namespace": i.metadata.namespace,
            "labels": i.spec.template.metadata.labels,
            "create_time": create_time,
            "run": i.status.replicas if i.status.replicas else 0,
            "status": i.status.conditions[0].status,
        }
        deployment_list.append(ns)
    return deployment_list


class ExporterApi:
    def __init__(self):
        # 注册收集器&最大耗时map
        self.collector_registry = CollectorRegistry(auto_describe=False)

        # 接口调用summary统计
        self.deployment_list = Gauge(name="deployment",
                                     documentation="Num of request time summary",
                                     labelnames=("name", "image", "create_time", "run"),
                                     registry=self.collector_registry)

    # 获取/metrics结果
    def get_prometheus_metrics_info(self, handler):
        encoder, content_type = choose_encoder(handler.request.headers.get('accept'))
        handler.set_header("Content-Type", content_type)
        handler.write(encoder(self.collector_registry))

    # summary统计
    def set_prometheus_request_summary(self):
        data = list_namespaced_deployment(api_addr=api_addr, api_token=api_token, namespace=namespace)
        for i in data:
            print(i)
            name = i.get("name")
            image = i.get("image")
            create_time = i.get("create_time")
            run = i.get("run")
            self.deployment_list.labels(name, image, create_time, run).set("1")


global g_monitor


class MetricsHandler(tornado.web.RequestHandler):
    def data_received(self, chunk: bytes) -> Optional[Awaitable[None]]:
        pass

    def get(self):
        print('INFO', datetime.now(), "/metrics Get.")
        g_monitor.set_prometheus_request_summary()
        # 通过Metrics接口返回统计结果
        g_monitor.get_prometheus_metrics_info(self)


if __name__ == "__main__":
    try:
        g_monitor = ExporterApi()
        app = tornado.web.Application([(r"/metrics?", MetricsHandler), ])
        app.listen(80)
        print("listen:80")
        tornado.ioloop.IOLoop.current().start()
    except Exception as e:
        print(e)