How to implement email tracking solution?

nginX has a module called empty_gif that generates a 1*1 pixel image. It is usually put at the end of campaign emails in order to track how many users have opened the email. The code for nginX is:

location = /empty.gif {
     empty_gif;
     expires -1;
     post_action @track;
 }

 location @track {
    internal;
     proxy_pass http://tracking-backend/track$is_args$args;
    proxy_set_header    x-ip     $remote_addr;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
 }

The above code check if /empty.gif URL is requested, if answer is yes then serve the image and makes expires to -1 to not cache the image and finally using post_action which calls a sub request after the current request has been fininshed. The parameters you need to pass is put after the image link in email like:

https://www.example.com/empty.gif?token=SOMETHING_TO_TRACK

#nginx #email #empty_gif #email_tracking #pixel

A collection of useful nginX configurations:

https://github.com/lebinh/nginx-conf#sub-request-upon-completion

#github #nginx

https://stackoverflow.blog/2018/09/05/developer-salaries-in-2018-updating-the-stack-overflow-salary-calculator/?cb=1

#salary #stackoverflow #report

#ebook #pdf #epub #vue

#ebook #mobi #pdf #docker #windows

https://ewanvalentine.io/microservices-in-golang-part-1/

#go #golang #microservice #docker #kubernetes #consul

https://realpython.com/python-web-scraping-practical-introduction/

#python #requests #web_scraping

How to convert the below line of string:

data = '15 0 42 50 "some text" "" 4 4 "text"'

into:

[15, 0, 42, 50, 'some text', '', 4, 4, 'text']

As you may have noted you cannot use split as there are texts with spaces in between. For that we can use the below code:

import csv
 import io

 file = io.StringIO(data)  # use io.BytesIO in python 2
 reader = csv.reader(file, delimiter=' ')
 split_data = next(reader)
 parsed_data = [int(x) if x.isdigit() else x for x in split_data]

NOTE: use io.BytesIO instead of io.StringIO in case you are using python 2.

#python #csv #reader #split #stringIO #byteIO

https://svgporn.com/

#logos #svg #logo

#ebook #pdf #mobi #security #cyber_security

#ebook #pdf #mobi #security #kali #linux #ethical_hacker #cookbook

How to disable visual block in VIM?

There is a feature in vim that as you select a text inside of vim, it turns the mode into VISUAL BLOCK. This is annoying for me in case you want to disable it put the below code in ~/.vimrc:

set mouse-=a

#vim #visual_block #mouse #set #vimrc

https://www.bloomberg.com/news/features/2018-10-04/the-big-hack-how-china-used-a-tiny-chip-to-infiltrate-america-s-top-companies

#news #china #amazon #hack

#ebook #pdf #mobi #python #cookbook

nethogs is used to monitor network traffic. You can see which processes use the most bandwidth and hogs the network.

Installtion on debian:

apt-get install nethogs

You can give the nethogs a network interface to see what's going on under the hood:

nethogs eth0

The output would something like:

PID USER       PROGRAM                                                       DEV        SENT      RECEIVED
9023 root      python                                                        eth0        6.083     175.811 KB/sec
20745 root     python                                                        eth0        2.449      45.715 KB/sec
11934 www-da.. nginx: worker process                                         eth0      131.580      20.238 KB/sec
25925 root     /usr/bin/python                                               eth0        3.674      10.090 KB/sec

When nethogs is open, you can press r in order to sort based on RECEIVED or press s to sort based on SENT packets. To change the mode that it is shown for KB/sec press m multiple times and see the output.

#network #sysadmin #linux #nethogs #nethog #network #eth0