sivalingams

Scaling your API with rate limiters

The following are examples of the four types rate limiters discussed in the accompanying blog post. In the examples below I've used pseudocode-like Ruby, so if you're unfamiliar with Ruby you should be able to easily translate this approach to other languages. Complete examples in Ruby are also provided later in this gist.

In most cases you'll want all these examples to be classes, but I've used simple functions here to keep the code samples brief.

Request rate limiter

This uses a basic token bucket algorithm and relies on the fact that Redis scripts execute atomically. No other operations can run between fetching the count and writing the new count.

sivalingams

  def get_random_string(length=5)
    source=("a".."z").to_a + ("A".."Z").to_a + (0..9).to_a + ["_","-","."]
    key=""
    length.times{ key += source[rand(source.size)].to_s }
    return key
  end

sivalingams

# Copyright 2017 Google Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,

sivalingams

#  ---------------------------------------------------------------------------
#
#  Description:  This file holds all my BASH configurations and aliases
#
#  Sections:
#  1.   Environment Configuration
#  2.   Make Terminal Better (remapping defaults and adding functionality)
#  3.   File and Folder Management
#  4.   Searching
#  5.   Process Management

sivalingams

Keybase proof

I hereby claim:

• I am sivalingams on github.
• I am sivalingam (https://keybase.io/sivalingam) on keybase.
• I have a public key whose fingerprint is 0C98 9B53 7D1A BCA9 85FC 4341 237A 7155 FE78 C0C0

To claim this, I am signing this object:

sivalingams

• Setup Database

create database [db-name];
revoke all on schema public from public;
create schema [schema-name];
create table [schema-name].[table-name](
  ...
) 

sivalingams

import sys
from xml.dom.minidom import _get_StringIO
from lxml import html
import requests
import os
import re
import time
import datetime
import csv
import urllib2