如何在 Flask 的路线中跟踪每个 function 所用的时间？

Question

现在我正在尝试捕获 flask 中每个请求的统计信息，我能够捕获完成请求所需的时间。 有没有办法捕获路线内每个 function 所花费的时间。

MY Code capturing the time taken by a route
@app.teardown_request
def teardown_func(response):
    print("tearing down reqest")
    print("Request",request)
    required_data = {
        "path": request.full_path,
        "url": request.url,
        "json_data": request.get_json(),
        "start": request.start_time,
        "stop": dt.utcnow(),
        "total_elapsed_time": (dt.utcnow() - request.start_time).total_seconds()
    }
    print("request data",required_data)
    return response

def call_func():
    sleep(5)
    print("FunctionCalled")

def another_func():
    sleep(5)
    print("FunctionCalled2")


@app.route('/',methods=['GET','POST'])
def hello2():
    time.sleep(10)
    call_func()
    another_func()
    return 'Hello World'

如何计算 call_func() 和 another_func() 在执行该路由时需要 5 秒？

Answer 1

一种方法是在您希望计时的函数周围使用装饰器。 然后，装饰器会将 function 的名称和timings的运行时间添加到保存在应用程序全局g属性中的字典中。 这可以记录在teardown_request或after_request钩子中，或者像这里所做的那样，通过/视图 function 记录：

from flask import Flask, Response, g
import time

app = Flask(__name__)

@app.before_request
def before_request_func():
    g.timings = {}

from functools import wraps
def time_this(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        start = time.time()
        r = func(*args, **kwargs)
        end = time.time()
        g.timings[func.__name__] = end - start
        return r
    return wrapper


@time_this
def call_func():
    time.sleep(1)

@time_this
def another_func():
    time.sleep(2)

@app.route('/',methods=['GET','POST'])
def hello2():
    call_func()
    another_func()
    return Response('Hello World: ' + str(g.timings), mimetype='text/plain')

更新

I just want to make the point that when you time a view function, the timing will not be created and added to the timings dictionary until after the function returns, so in that case the timings dictionary is best processed in an after_request hook function, for例子：

@app.after_request
def after_request_func(response):
    # just append timings to the output response:
    response.data += ('\n' + str(g.timings)).encode('ascii')
    return response

@app.route('/',methods=['GET','POST'])
@time_this
def hello2():
    call_func()
    another_func()
    return Response('Hello World', mimetype='text/plain')

输出：

Hello World
{'call_func': 1.0014231204986572, 'another_func': 2.0004665851593018, 'hello2': 3.001889705657959}