clientSpider/handleManager.py

#!-*-encoding:utf-8-*-

"""
Faas 脚本定位函数
"""

import pkgutil
import operator
import importlib
import os
import traceback
from inspect import getmembers, isclass, isfunction

import json

# -------------------------------------配置-------------------------------------------------------

handlerFileName = 'spider_result_handler'
py_code_source_dir = os.environ.get('FAAS_CODE_DIR', 'F:/codes/python/clientSpider/')

py_code_handler_path_list = [py_code_source_dir + handlerFileName]
# 安全考虑，只能调用该目录下的方法，而不是任意模块方法，且作为 faas 服务内部约定，外部服务不需要感知该模块/目录名；但其目录下子目录/模块不做限制
py_code_handler_module_prefix = handlerFileName + '.'

# --------------------------------------约定------------------------------------------------------
faas_function_name__support = 'support'
faas_function_name__handle = 'handle'

const_key_function_id = "faas__function-id"
const_key_request_wrap = "faas__request_wrap"
const_key_params = "faas__req.params"
const_key_context = "faas__req.context"
const_key_result = "faas__invoke_result"
const_key_result_success = "faas__success"
const_key_reload = "faas__reload"
const_key_trace_id = "faas__trace_id"

# --------------------------------------上下文------------------------------------------------------
# 全局上下文(配置 稀缺连接)
    # 模块上下文(模块加载后存在的, 模块版本信息 )
    # 全局线程上下文(普通连接)
# 线程任务上下文(任务 任务间传递信息 模块线程上下文)


# --------------------------------------动态加载------------------------------------------------------

loaded_functions_cache = {}


# todo 进程锁
def load_functions(force_reload_module):
    """
    加载指定目录下的所有函数
    """
    func_dic = {}

    for importer, name, ispkg in pkgutil.walk_packages(py_code_handler_path_list, py_code_handler_module_prefix):
        if not ispkg and not operator.contains(name, 'test'):
            module = importlib.import_module(name)

            if force_reload_module:
                importlib.reload(module)

            # 遍历 module 中的元素， 取出所有的成员函数
            rest_dic = dict([(("%s-%s") % (name, func_name), value) for (func_name, value) in getmembers(module) if
                             isfunction(value)])
            func_dic.update(rest_dic)

    global loaded_functions_cache
    loaded_functions_cache = func_dic


# 函数路由
def func_route(func_dic, func_name, args={}):
    """
    函数路由: 根据函数名执行调用
    """
    # fixme 判断是否存在
    func = func_dic[func_name]
    print(func)

    if len(args) > 0:
        resp = func(**args)
    else:
        resp = func()

    return resp


def handle(pycode_file_name, req):
    """
    handle a request to the function
    Args:
        pycode_file_name (str): python file
        req (str): request body
    :returns json
    """

    json_req = json.loads(req)

    support_func_name = py_code_handler_module_prefix + "%s-%s" % (pycode_file_name, faas_function_name__support)
    pycode_function_id = py_code_handler_module_prefix + "%s-%s" % (pycode_file_name, faas_function_name__handle)

    global loaded_functions_cache

    if const_key_reload in json_req:
        load_functions(True)

    # print("函数字典keys：{}".format(func_dic.keys()))
    # pycode_file_name = json_req[const_key_function_id] if const_key_function_id in json_req else None
    if not loaded_functions_cache.get(pycode_function_id):
        load_functions(True)

    args = json_req
    success = False
    result = None

    try:
        result = func_route(loaded_functions_cache, pycode_function_id, args)
        success = True
        print(pycode_function_id + ' SUCCESS')
    except Exception as e:
        print(pycode_function_id + ' Error: ' + traceback.format_exc())
        pass

    faas_resp = {
        const_key_result_success: success,
        const_key_context: json_req[const_key_request_wrap][const_key_context],
        const_key_function_id: pycode_function_id,
        const_key_result: result
    }

    #faas_resp = json.dumps(faas_resp)

    return faas_resp


if __name__ == "__main__":
    """
    测试handle
    """
    reqInfo = {
        const_key_request_wrap: {
            const_key_context: {"contextKey1": "k1", "contextKey2": "k2"},
            const_key_params: {"param1": "a", "param2": "b"}
        }
    }

    resp = handle("cat", json.dumps(reqInfo))

    print(resp)