Infrastructure & Reliability on Pablo Seminario

Building a serverless Telegram bot

Mon, 03 Sep 2018 18:48:00 +0000

With the arrival of FaaS and all the serverless infrastructure providers (AWS, Google Cloud, Azure, etc) now is easy to deploy our own Telegram bot.

A Webhook-based bot it’s the perfect use case for serverless computing, using for example Google Cloud Functions we’ll have all these advantages:

Our function will be associated to a public endpoint (IPv4 and IPv6) over HTTPS (using a valid certificate provided by Google)
Pay only for function invocations and its compute resources consumption, so it could be cheaper than paying for a server powered on all the time
No server management
Scales automatically

Requirements

Before start building your bot you’ll need to:

Register a new bot following these instructions core.telegram.org/bots in order to get an API token
Using a Google Cloud account, register a new project, enable the Cloud Functions API and install the Cloud SDK following the official quickstart

Code

In a few lines of Python you can code a simple echo bot that will reply with the same message that it receives:

 text
 text
 
# main.py
import os
import telegram

def webhook(request):
 bot = telegram.Bot(token=os.environ["TELEGRAM_TOKEN"])
 if request.method == "POST":
 update = telegram.Update.de_json(request.get_json(force=True), bot)
 chat_id = update.message.chat.id
 # Reply with the same message
 bot.sendMessage(chat_id=chat_id, text=update.message.text)
 return "ok"

The only dependency needed is the amazing python-telegram-bot library:

 text
 text
 
# requirements.txt 
python-telegram-bot==11.1.0

Notes about Android and IPsec on Linux

Sat, 23 Apr 2016 21:35:00 +0000

Here’s some personal notes about the excellent Jeff Sharkey’s article Deploying a pure-IPsec PKI VPN server for Android devices

My setup is a little bit different to that of Jeff, I have a 1Gbps fiber plan, a Linux server natted behind my ISP’s router and my IPsec VPN server is running on a Linux container (LXC), so this container doesn’t have a public IP address. The OS used in all the servers is Ubuntu Trusty 14.04. On the VPN client side I’m using Android 6.0 Mashmallow.

You Build It, You Run It

Sun, 05 Apr 2015 20:38:00 +0000

Giving developers operational responsibilities has greatly enhanced the quality of the services, both from a customer and a technology point of view. The traditional model is that you take your software to the wall that separates development and operations, and throw it over and then forget about it. Not at Amazon. You build it, you run it. This brings developers into contact with the day-to-day operation of their software. It also brings them into day-to-day contact with the customer. This customer feedback loop is essential for improving the quality of the service.

DNS resolution for LXC in Ubuntu 14.04

Sun, 27 Jul 2014 15:28:00 +0000

Working with LXC (Linux containers) in Ubuntu is very easy but by default you need to know the IP address of new containers to connect to services (ssh, database, webserver, etc.) running on them.

With some minor configuration you can connect to your containers using a domain name like that

 terminal
 bash
 
$ sudo lxc-create --name container1
$ sudo lxc-start --name container1 --daemon
$ ssh ubuntu@container1.lxc

In Ubuntu 14.04 Trusty Tahr, lxc-create use by default the Ubuntu template and it will create a user called ubuntu, to change it take a look at the template options with lxc-create -t ubuntu -h.

Do not program defensively

Thu, 19 Dec 2013 08:49:00 +0000

Most of the code in the system should be written with the assumption that the input data to the function in question is correct. Only a small part of the code should actually perform any checking of the data. This is usually done when data enters the system for the first time, once data has been checked as it enters the system it should thereafter be assumed correct.

source: Program Development Using Erlang

The value of breaking the law

Wed, 17 Jul 2013 08:20:00 +0000

Interesting post and essay about the value and the ability to break the law.

source: Bruce Schneier’s blog

Running Scrapy on Amazon EC2

Tue, 26 Mar 2013 16:21:00 +0000

Sometimes can be useful to crawl sites with Scrapy using temporary resources on the cloud, and Amazon EC2 is perfect for this task. You can launch an Ubuntu OS instance and schedule your spiders using the Scrapyd API. With boto, a python interface to Amazon Web Services, you can launch instances and install the scrapy daemon using the user data feature to run a script on boot.

First, you need an AWS account with your access keys, a EC2 security group accepting TCP connections on port 6800 and a key pair for the selected region. After that you must choose an Ubuntu EC2 image, here you can find a list of Ubuntu AMIs.

World IPv6 day

Wed, 06 Jun 2012 21:53:00 +0000

To celebrate the world IPv6 day I decided to activate IPv6 on this blog. Now you can visit my site with native IPv6 connectivity.

If you want to know more about IPv6 you can start reading this overview.

Installing Solr on Debian 6.0

Tue, 22 Feb 2011 19:29:00 +0000

Update: this is an old blog post, Solr is now included in Debian since 7.0, it can be installed through apt-get by calling apt-get install solr-tomcat.

Recently I’ve been working on a Django project that uses the Haystack search API and the Solr search engine to perform full text searching on indexed data.

This project was initially deployed on a Debian 5.0 (Lenny) server with some issues with Tomcat, but using the latest stable release of Debian (code named Squeeze) install Tomcat 6 and Solr is very easy.

ext4 support in Ubuntu Intrepid 8.10

Wed, 01 Jul 2009 01:34:00 +0000

This is just a simple tip to use ext4 filesystems in Ubuntu Intrepid Ibex 8.10. On Ubuntu Jaunty ext4 filesystems is fully supported but in Intrepid was on development. To use it we must load the module ext4dev

 terminal
 bash
 
sudo modprobe ext4dev

to check the filesystems supported by the kernel we can do

 terminal
 bash
 
cat /proc/filesystems

there should be a line with ext4dev. Now, if we try to mount a formatted partition as ext4, we will see that it’s not possible

Mi clave GPG comprometida

Mon, 22 Sep 2008 14:53:00 +0000

Con el robo de amidala (mi laptop) mi clave GPG privada que iba dentro quedo comprometida. Pero con la copia de la clave privada y del certificado de revocación que tenía revoké mi clave en pks.lugmen.org.ar

gpg --import revoke-cert.asc
gpg --keyserver pks.lugmen.org.ar --send-keys 555B6773

Con esto no se borra mi clave en el servidor pero ya aparece como revocada.

Keysigning Party @LUGMen

Fri, 13 Jun 2008 02:36:00 +0000

Como algunos sabrán y para los que no también, en la reunión pasada de LUGMen se hizo una keysigning party, hace casi una semana, pero por los efectos del alcohol olvidé mi cámara con las fotos de la reunión en la casa de unos amigos :P Pero acá están. Solo faltaron 2 de los 15 que confirmaron su presencia. Se habló sobre criptografía, nos reímos de los nombres reales y las fotos de los documentos de cada uno, y como siempre hubo tortitas y Coca-Cola®. Así quedo actualmente mi anillo de confianza

Instalando una TDM400P sobre Etch

Wed, 22 Nov 2006 12:23:00 +0000

Introducción

Para que Asterisk pueda hacer uso de la red telefónica conmutada (PSTN) es necesario contar con una interfaz, la misma la proveen los módulos de hardware FXS o FXO, que permiten la interconexión directamente a teléfonos o a las líneas telefónicas. En mi caso tengo una TDM400P que tiene integrados dos módulos FXO y dos módulos FXS. Todo esto lo haremos funcionar sobre un Debian GNU/Linux Etch con kernel 2.6.17.