send_code_metrics.py

import functools
import logging
import graypy
import json
import time
import random
from collections import defaultdict, deque
from flask import Flask, jsonify, g

app = Flask(__name__)

class Encoder(json.JSONEncoder):
    def default(self, obj):
        base = super(Encoder, self).default
        # specific encoder for the timed functions
        if isinstance(obj, deque):
            calls = list(obj)
            return {'num_calls': len(calls), 'min': min(calls), 'max': max(calls), 'values': calls}
        return base(obj)

def timeit(func):
    @functools.wraps(func)
    def _timeit(*args, **kw):
        start = time.time()
        try:
            return func(*args, **kw)
        finally:
            if 'timers' not in g:
                g.timers = defaultdict(functools.partial(deque, maxlen=5))
            g.timers[func.__name__].append(time.time() - start)
    return _timeit


@timeit
def fast_stuff():
    time.sleep(.001)

@timeit
def some_slow_stuff():
    time.sleep(random.randint(1, 100) / 100.)

def set_view_metrics(view_func):
    @functools.wraps(view_func)
    def _set_view_metrics(*args, **kw):
        try:
            return view_func(*args, **kw)
        finally:
            app.logger.info(json.dumps(dict(g.timers), cls=Encoder))
    return _set_view_metrics

def set_app_metrics(app):
    for endpoint, func in app.view_functions.items():
        app.view_functions[endpoint] = set_view_metrics(func)


@app.route('/api', methods=['GET', 'POST'])
def my_microservice():
    some_slow_stuff()
    for i in range(12):
        fast_stuff()
        resp = jsonify({'result': 'OK', 'Hello': 'World!'})
        fast_stuff()
    return resp


if __name__ == '__main__':
    handler = graypy.GELFHandler('localhost', 12201)
    app.logger.addHandler(handler)
    app.logger.setLevel(logging.INFO)
    set_app_metrics(app)
    app.run()