Microservices Architecture is a well-known pattern for building a complex system that consists of loosely coupled modules. It provides better scalability, and it is easier to develop a system in multiple teams so that they don’t interfere with each other too much. However, it is important to choose the right way of communication between the services. Otherwise, this kind of architecture can do more harm than good.
Originally posted on DEV.to
In my previous post, I touched on the point that Redis is more than just an in-memory cache.
Most people do not even consider Redis as a primary database. There are a lot of use cases where Redis is a perfect choice for non-cache related tasks.
In this article, I will demonstrate how I built a fully functional Q&A board for asking and upvoting the most interesting questions. Redis will be used as a primary database.
I will use Gatsby (React), Netlify serverless functions and Upstash Serverless Redis.
Upstash has been a good choice so far and I decided to try it out in a more serious project. I love everything serverless and how it makes things simpler for me.
Serverless will be a great choice for most tasks however you need to know the pros and cons of the tech you are using. I encourage you to learn more about serverless to get the most out of it.
The developer or owner of a software product often faces the question of choosing a suitable location for hosting server capacity. As you know, software always meets hardware.
In the previous article we refreshed our memory of WebRTC CDN and the ways this technology helps to minimize latency for WebRTC streams. We also discussed why load balancing and autoscaling wouldn't be amiss in CDNs. Here are the main points from the article:
The modern browsers do not give users a choice between using WebRTC and not using it. And while you can playback streams using HLS or MSE, WebRTC remains the only tool for capturing camera feeds and publishing streams from a browser. The browser developers have accepted this "format" and integrated it into their products – just as they used to support the Flash Player as a plugin. The only difference is that WebRTC comes natively integrated into the browser — as code, not a plugin. If, in a few years, a new and better library for video streaming is introduced they will undoubtedly make a switch. But these days, Chrome maintains its dominance, so no contenders for WebRTC are in sight.
Setting up Atom for working with python is quite a tricky task. I've spent a lot of time making it work. Autocompleting, autoformatting, type hints, and much more will be available to you after reading this tutorial.
The vast majority of IT specialists in various fields strive to perform manually as few actions as possible. I won't be afraid of the loud words: what can be automatized, must be automatized!
Let's imagine a situation: you need to deploy a lot of servers of the same type and do it quickly. Quickly deploy, quickly undeploy. For example, to deploy test rigs for developers. When development is carried out in parallel, you may need to separate the developers, so they don't impede each other and possible errors of one of them don't block the work of the others.
There may be several ways to solve this problem:
The PVS-Studio website turns 15 this year. This is quite significant for any internet resource. Back then, when our website was born, Russia announced 2006 as a year of humanities. That same year, in June, Denis Kryuchkov established a new platform, "Habrhabr" (now known as Habr). In November, Microsoft officially completed OS Windows Vista. That same month we registered the viva64.com domain.
We celebrated our domain's 10th anniversary with the website's redesign. After that, we would only change the resource capacity and features, but we'd never touch the design in any way. During this time, the number of articles grew so much that we needed to add tags to facilitate navigation. Right now we are also working on our YouTube channel. This means, you will see more and more new videos on our website as well. We keep adding new web pages at a tremendous rate, while the website's usability stays the same.
Time has come for big changes!
I have already written about AIOps and machine learning methods in working with IT incidents, about hybrid umbrella monitoring and various approaches to service management. Now I would like to share a very specific algorithm, how one can quickly get information about functioning conditions of business applications using synthetic monitoring and how to build, on this basis, the health metric of business services at no special cost. The story is based on a real case of implementing the algorithm into the IT system of one of the airlines.
Currently there are many APM systems, such as Appdynamics, Dynatrace, and others, having a UX control module inside that uses synthetic checks. And if the task is to learn about failures quicker than customers, I will tell you why all these APM systems are not needed. Also, nowadays health metrics are a fashionable feature of APM and I will show how you can build them without APM.
We describe the implementation of a custom Domain Name System (DNS) by using C socket programming for network communication, together with SQLite3 database for the storage of Internet Protocol (IP) for Uniform Resource Locator (URL). Then we provide a performance analysis of our implementation. Our code is available publicly .
In this topic, I will tell you how to dynamically parse and deserialize only part of the whole JSON document. We will create an implementation for .NET Core with C# as a language.
For example, we have the next JSON as a data source for the report. Notice that we will get this JSON in the runtime and at the compile step we don't know the structure of this document. And what if you need to select only several fields for processing?
Hi, My name is Alex and I am a DevOps engineer at Altenar. “No Windows, no problems.” - that is the answer I got by asking a guru of Ansible "How do you manage Windows?" on one of the local Ansible meetups. Although we have been running a modern stack (k8s, helm, .net core, etc) in production for about two years, that’s not how it has always been.
PVS-Studio user support often receives clients' suggestions on product improvement. We are happy to implement many of them. Recently one of the users suggested refining the automatic notification utility for developers (Blame Notifier). They asked us to make Blame Notifier extract the date/the code revision to which the analyzer issued a message using blame information from the version control system. This feature allowed us to expand the utility capabilities, which we'll discuss in this article.
"How much longer are you going to build it?" - a phrase that every developer has uttered at least once in the middle of the night. Yes, a build can be long and there is no escaping it. One does not simply redistribute the whole thing among 100+ cores, instead of some pathetic 8-12 ones. Or is it possible?
FTPS - is FTP with SSL layer, please don't mess it with SFTP. FTPS uses regular FTP protocol underneath, but all commands and data is encrypted using SSL. So mechanism of work is pretty same as in HTTPS: old protocol encapsulated in security layer. But that's breaks a lot of traditional FTP clients you are used to.
So here is 2 dead simple solutions I've tested with many FTPS servers, which setup could be much more correct then it actualy was. You can encounter FTPS servers configured in 2 ways with ports 20 + 21 and 989 + 990 used.
Filezilla is a GUI client available for both linux and windows. It has pretty specific interface. It can correctly handle wrong certificates, unusual ports and so on. Can be downloaded here. Just enter host, username, password and port(only if needed) and press Connect.
Mounting FTPS under linux
There is a an utililty called curlftpfs. It works under linux/*bsd and allows to mount remote FTPS(S) dir to you local directory. So in the simpliest ways on the ubuntu/debian it will look like:
sudo apt install curlftpfs
curlftpfscurlftpfs -o ssl ftp://USERNAME:PASSWORD@HOSTNAME:21/ /tmp/ftp-mount
If server you connecting to has wrong or outdated SSL certificate you can try:
curlftpfs -o ssl,no_verify_peer,no_verify_hostname ftp://USERNAME:PASSWORD@HOSTNAME:21/ /tmp/ftp-mount
If you need to change port from 21 to something else, remember, you can change port only in connection string, maybe via .netrc, but NOT with curlftpfs ftp_port option.
If you know a solution that allows to mount ftps folders under Windows, please mention it in comments.
Smoothly the era of mesh-networks is upon us. At the very least, the term is appearing more and more often in the information sphere. What attracts the attention of networkers? Let's try to understand the question, taking Yggdrasil network as an example as one of the most promising prototypes. The article is intended for a wide range of readers.
Hey, hey! I am Ilya Kalchenko, a Data Engineer at NIX, a fan of big and small data processing, and Python. In this article, I want to discuss the benefits of hybrid data lakes for efficient and secure data organization.
To begin with, I invite you to figure out the concepts of Data Warehouses and Data Lake. Let’s delve into the use cases and delimit areas of responsibility.
The year 2021 started on such a high note for Qrator Labs: on January 19, our company celebrated its 10th anniversary. Shortly after, in February, our network mitigated quite an impressive 750 Gbps DDoS attack based on old and well known DNS amplification. Furthermore, there is a constant flow of BGP incidents; some are becoming global routing anomalies. We started reporting in our newly made Twitter account for Qrator.Radar.
Nevertheless, with the first quarter of the year being over, we can take a closer look at DDoS attacks statistics and BGP incidents for January - March 2021.
In this article, we benchmark the performance of MySQL 8 default configuration vs. innodb_dedicated_server enabled configuration vs. the configuration recommended by MySQL Performance Tuning Service.
Types of smart traffic lights: adaptive and neural networks
Adaptive works at relatively simple intersections, where the rules and possibilities for switching phases are quite obvious. Adaptive management is only applicable where there is no constant loading in all directions, otherwise it simply has nothing to adapt to – there are no free time windows. The first adaptive control intersections appeared in the United States in the early 70s of the last century. Unfortunately, they have reached Russia only now, their number according to some estimates does not exceed 3,000 in the country.
Neural networks – a higher level of traffic regulation. They take into account a lot of factors at once, which are not even always obvious. Their result is based on self-learning: the computer receives live data on the bandwidth and selects the maximum value by all possible algorithms, so that in total, as many vehicles as possible pass from all sides in a comfortable mode per unit of time. How this is done, usually programmers answer – we do not know, the neural network is a black box, but we will reveal the basic principles to you…
Adaptive traffic lights use, at least, leading companies in Russia, rather outdated technology for counting vehicles at intersections: physical sensors or video background detector. A capacitive sensor or an induction loop only sees the vehicle at the installation site-for a few meters, unless of course you spend millions on laying them along the entire length of the roadway. The video background detector shows only the filling of the roadway with vehicles relative to this roadway. The camera should clearly see this area, which is quite difficult at a long distance due to the perspective and is highly susceptible to atmospheric interference: even a light snowstorm will be diagnosed as the presence of traffic – the background video detector does not distinguish the type of detection.