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Travis CI is a distributed web service for building and testing software that uses GitHub as a source code hosting service. In addition to the above scripts, you can add your own, thanks to the extensive configuration options. In this article we will set up Travis CI for working with PVS-Studio by the example of PPSSPP code.

A developer, who first encountered generating emails, has almost no chance to write an application, that will do it correctly. Around 40% of emails, generated by corporate applications, are violating some form of standard, and due to this, there are problems with delivery and display. There are reasons for this: emails are technically more difficult than the web, and operating emails is regulated by a few hundred standards, as well as an uncountable number of generally accepted (and not as much) practices, whereas the email clients are more varied and unpredictable than browsers. Testing may significantly improve the situation, but materials that are dedicated to testing the email system, are practically non-existent.

Mail.ru regularly interacts with its users by email. In our projects, all the components responsible for generating emails and even individual mailings, are subject to mandatory testing. In this article, we will share our experience (learning from our mistakes).

There’s a problem we needed to address in the course of developing our games. It’s complicated to generate a random number in a distributed network. Almost all blockchains have already faced this issue. Indeed, in networks where there is no trust between anyone, the creation of a random number solves a wide range of problems.

In this article, we explain how we solved this problem for our games. The first of these was Waves Xmas Tree.

TL;DR: Client-server architecture of our internal configuration management tool, QControl.
At its basement, there’s a two-layered transport protocol working with gzip-compressed messages without decompression between endpoints. Distributed routers and endpoints receive the configuration updates, and the protocol itself makes it possible to install intermediary localized relays. It is based on a differential backup (“recent-stable,” explained further) design and employs JMESpath query language and Jinja templating for configuration rendering.

Qrator Labs operates on and maintains a globally distributed mitigation network. Our network is anycast, based on announcing our subnets via BGP. Being a BGP anycast network physically located in several regions across the Earth makes it possible for us to process and filter illegitimate traffic closer to the Internet backbone — Tier-1 operators.

On the other hand, being a geographically distributed network bears its difficulties. Communication between the network points-of-presence (PoP) is essential for a security provider to have a coherent configuration for all network nodes and update it in a timely and cohesive manner. So to provide the best possible service for customers, we had to find a way to synchronize the configuration data between different continents reliably.

In the beginning, there was the Word… which quickly became communication protocol in need of an upgrade.

Developer Christophe Verdot shares his experiences of recently taking the online course ‘Mastering Web 3.0 with Waves’.



What is your background? What motivated you to take the course?

I’ve been a web developer for about 15 years, working mostly as a freelancer.

Technology is rapidly changing all parts of our life. This is starting to impact the way that you grill your food. We’ve seen some new wi-fi grills hitting the market. But what is this and what advantages does it have over the other grills on the market? Let’s delve deeper into the world of wi-fi grills to find these answers.

What is a Wi-Fi Grill?

Over the last few years, we’ve seen the rise of wi-fi technology. It’s allowed us to automate our lives, making a lot of things easier. For example, now you’ll be able to turn on the lights at home from an app on your phone. You can start preheating the oven for dinner when you leave the office. This technology has always existed in the world of grilling. For example, you could purchase a thermometer, which lets you monitor the internal temperature of the meat from your phone.
A grill with wi-fi, though, takes this concept to the next level. Using this technology, you’ll be able to control a lot of aspects of the grilling process. For example, you’ll be able to set the temperature of the grill. Sensors in the grill will then help to automatically adjust the heat to fit your preferences. You can also control when the grill turns itself on and off. The features will often depend on the model that you purchase.

PVS-Studio supports analyzing projects developed in C, C++, C#, and Java. You can use the analyzer under Windows, Linux, and macOS. This small article will tell you the basics of analyzing C and C++ code in Linux environment.

Installation

There are different ways to install PVS-Studio under Linux, depending on your distro type. The most convenient and preferred method is to use the repository, since it allows auto-updating the analyzer upon releasing new versions. Another option is to use the installation package, which you can get here.

One thing about WebSockets is that you need a lot of resources on the client's side to generate high enough load for the server to actually eat up all the CPU resources.

There are several challenges you have to overcome because the WebSockets protocol is more CPU demanding on the client's side than on the server's side. At the same time you need a lot of RAM to store information about open connections if you have millions of them.

I've been lucky enough to get a couple of new servers for a limited period of time at my disposal for the hardware "burnout" tests. So I decided to use my Lua Application Server — LAppS to do both jobs: test the hardware and perform the LAppS high load tests.

On May 10, we announced the limited beta of GitHub Package Registry, a package management service that makes it easy to publish public or private packages next to your source code. It currently supports familiar package management tools: JavaScript (npm), Java (Maven), Ruby (RubyGems), .NET (NuGet), and Docker images, with more to come.

Today we’re excited to announce that we’ll be adding support for Swift packages to GitHub Package Registry. Swift packages make it easy to share your libraries and source code across your projects and with the Swift community.

In today’s contemporary world the private computer has become a staple of daily life.
Even those few persons who don't use computers in their daily work life can possibly have access to a computer on that they perform alternative necessary tasks.

With all of the access to info that computers permit and with all of the work they will facilitate a personal perform, this trend of a computer in every home and in each workplace of business isn't shocking.

But what may be shocking, and downright aggravating, is when the computer you are working on suddenly shuts off, goes blank, or explodes in the dreaded blue screen of death.

These and other common computer problems are among the most frequently occurring issues that one might experience with their computers.

The following may be a list of 5 common Computer issues and what may be done to mend them.

Hi All,

I’m in the process of implementing a new simple microservices-based project as an example of a step-by-step guide for those who had a hard time with a microservices architecture and are still looking for “another” good reference. Also, I would really appreciate thought through feedback and proposal to make this project a high-quality chunk of work.

There are tons of articles and source code examples. But, unfortunately, I could not find any reference with simple step-by-step instructions, without doing a deep dive into Docker, Event Store, a multitude of configurations, cloud deployment stuff, etc. I cloned several projects and tried to start playing with them, but you know, only God knows how to start them, which dependencies are missing and why all those scripts are failing with thousands of ERRORS.

For example, this eShop project from Microsoft contains all we need, but it is not so simple to figure out what is going on there, SQL database connection strings, Docker scripts fail, no How-Tos and I’m not sure it is super-simple architecture you need to start with.

At the moment, cloud CI systems are a highly-demanded service. In this article, we'll tell you how to integrate analysis of source code into a CI cloud platform with the tools that are already available in PVS-Studio. As an example we'll use the Travis CI service.

Dr. Martin Kleppmann is a researcher in distributed systems at the University of Cambridge, and the author of the highly acclaimed «Designing Data-Intensive Applications» (O'Reilly Media, 2017). 

Kevin Scott, CTO at Microsoft once said: «This book should be required reading for software engineers. Designing Data-Intensive Applications is a rare resource that connects theory and practice to help developers make smart decisions as they design and implement data infrastructure and systems.»

Martin’s main research interests include collaboration software, CRDTs, and formal verification of distributed algorithms. Previously he was a software engineer and an entrepreneur at several Internet companies including LinkedIn and Rapportive, where he worked on large-scale data infrastructure.

Vadim Tsesko (@incubos) is a lead software engineer at Odnoklassniki who works in Core Platform team. Vadim’s scientific and engineering interests include distributed systems, data warehouses and verification of software systems.

Contents:

• Moving from business to academic research;
  
• Discussion of «Designing Data-Intensive Applications»;
  
• Common sense against artificial hype and aggressive marketing;
  
• Pitfalls of CAP theorem and other industry mistakes;
  
• Benefits of decentralization;
  
• Blockchains, Dat, IPFS, Filecoin, WebRTC;
  
• New CRDTs. Formal verification with Isabelle;
  
• Event sourcing. Low level approach. XA transactions; 
  
• Apache Kafka, PostgreSQL, Memcached, Redis, Elasticsearch;
  
• How to apply all that tools to real life;
  
• Expected target audience of Martin’s talks and the Hydra conference.
  

Hello Habr! Now that is summer vacation season. Many of you will take a flight to a place far from your everyday routine at home. Before this hot vacation season starts, we should discuss an interesting and useful method on how to save money using a VPN.

One of the easiest ways to see the value in this is looking at car rentals while on vacation.

Introduction

In mid-April, we published news about the Android.InfectionAds.1 trojan, which exploited several critical vulnerabilities in Android. One of them, CVE-2017-13156 (also known as Janus), allows malware to infect APK files without damaging the digital signature. The other one is CVE-2017-13315. It gives the trojan extended privileges, so that it can install and uninstall applications independently from user. A detailed analysis of Android.InfectionAds.1 is available in our virus library; while we’re here we will touch upon the CVE-2017-13315 vulnerability and see what it does.

Every now and then we create our own problems with our own hands… with our vision of the world… with our inaction… with our laziness… and with our fears. As a result, it seems to become very convenient to swim in the public flow of sewage patterns… because it is warm and fun, and the rest does not matter – we can smell round. But after a fail comes the realization of the simple truth – instead of generating an endless stream of causes, self-pity and self-justification, it is enough just to do what you consider the most important for yourself. This will be the starting point for your new reality.

For me, the written below is just such a starting point. The way is expected to be lingering…

We’re excited to announce starting today you can try the Windows Subsystem for Linux 2 by installing Windows build 18917 in the Insider Fast ring! In this blog post we’ll cover how to get started, the new wsl.exe commands, and some important tips. Full documentation about WSL 2 is available on our docs page.

Before reading this article, it is recommended to read the previous one: Audio over Bluetooth: most detailed information about profiles, codecs, and devices / по-русски

Some wireless headphone users note low sound quality and lack of high frequencies when using the standard Bluetooth SBC codec, which is supported by all headphones and other Bluetooth audio devices. A common recommendation to get better sound quality is to buy devices and headphones with aptX or LDAC codecs support. These codecs require licensing fees, that's why devices with them are more expensive.

It turns out that the low quality of SBC is caused by artificial limitations of all current Bluetooth stacks and headphones' configuration, and this limitation can be circumvented on any existing device with software modification only.

This article is also available in Russian / Эта статья также доступна на русском языке

The mass market of smartphones without the 3.5 mm audio jack changed headphones industry, wireless Bluetooth headphones have become the main way to listen to music and communicate in headset mode for many users.
Bluetooth device manufacturers rarely disclose detailed product specifications, and Bluetooth audio articles on the Internet are contradictory and sometimes incorrect. They do not tell about all the features, and often publish the same false information.
Let's try to understand the protocol, the capabilities of Bluetooth stacks, headphones and speakers, Bluetooth codecs for music and speech, find out what affects the quality of the transmitted audio and the delay, learn how to capture and decode information about supported codecs and other device features.

TL;DR:

• SBC codec is OK
• Headphones have their own per-codec equalizer and post processing configuration
• aptX is not as good as the advertisements say
• LDAC is a marketing fluff
• Voice audio quality is still low
• Browsers are able to execute audio encoders compiled to WebAssembly from C using emscripten, and they won't even lag.

Testing is an important part of the development process. And sometimes developers need to run tests locally, before committing changes.

If your application uses Amazon Web Services, python library moto is the perfect thing for that.