投稿時間:2021-11-30 00:37:44 RSSフィード2021-11-30 00:00 分まとめ(44件)

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AWS	AWS	Alef Education: Building an Adaptive Learning System for K12 Students using AWS	https://www.youtube.com/watch?v=Dp3YAxFp-YM	Alef Education Building an Adaptive Learning System for K Students using AWSAlef Education is a leading global education technology company that is at the forefront of using artificial intelligence and machine learning technologies to create personalised learning experiences that transform the way the world is educated Alef Education provides AI powered learning and teaching solutions that leverage real time data to drive improvements across the education ecosystem With the power of AI Alef Education aims to establish a holistic educational experience from the moment students acquire new knowledge to the step when the skills are reviewed and evaluated The solutions Alef Education provides also target both high performing students and at risk students leaving no student behind and catering to personalized needs Check out more resources for architecting in the AWS​​​cloud AWS AmazonWebServices CloudComputing ThisIsMyArchitecture	2021-11-29 14:41:02
python	Pythonタグが付けられた新着投稿 - Qiita	Python でテキストデータの会話文を1行に成型する	https://qiita.com/ph_ys2018/items/f90edfd02a846f2ba5d0	「」の対が要素に収まっているリストを返す関数をメモ代わりに記載する。	2021-11-29 23:13:13
python	Pythonタグが付けられた新着投稿 - Qiita	平仮名<==>カタカナ　変換	https://qiita.com/StrawBerryMoon/items/c256b533436d7398cb50	chrord	2021-11-29 23:02:34
js	JavaScriptタグが付けられた新着投稿 - Qiita	Vanilla JavaScript をずっと書いていたけど、Reactに入門してみた。	https://qiita.com/anderson0119/items/9b942da0415c275203c6	長文になりましたが、Reactに入門してみました。	2021-11-29 23:32:09
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	エラー: メイン・クラスcooking.CookingApplicationを検出およびロードできませんでした。	https://teratail.com/questions/371547?rss=all	エラーメイン・クラスcookingCookingApplicationを検出およびロードできませんでした。	2021-11-29 23:46:03
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	[Unity]扉を開閉した際の衝突を回避したい	https://teratail.com/questions/371546?rss=all	Unity扉を開閉した際の衝突を回避したいお世話になっております。	2021-11-29 23:44:51
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	pickerviewの文字固定	https://teratail.com/questions/371545?rss=all	下記の写真のように純正のアップルの時間アプリでは、pickerを回転させても「時間」などは回転せずに固定されています。	2021-11-29 23:42:28
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	Laravel: Image Interventionで作成した画像をビューに表示したい。	https://teratail.com/questions/371544?rss=all	LaravelImageInterventionで作成した画像をビューに表示したい。	2021-11-29 23:41:46
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	デバッグが開始されない。【VScode】	https://teratail.com/questions/371543?rss=all	デバッグが開始されない。	2021-11-29 23:27:43
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	コンテナを起動と同時にSQLを流したい（テーブル作成）	https://teratail.com/questions/371542?rss=all	コンテナを起動と同時にSQLを流したいテーブル作成前提・実現したいことコンテナを起動した際、create文を流したいのですが、上手くいきません。	2021-11-29 23:10:59
Program	[全てのタグ]の新着質問一覧｜teratail（テラテイル）	Wordpressの記事一覧を分割して表示したい	https://teratail.com/questions/371541?rss=all	Wordpressの記事一覧を分割して表示したい固定ページを作成中ですがページにつき件表示する設定で、記事を分割にして表示したいと思ってます。	2021-11-29 23:04:09
Git	Gitタグが付けられた新着投稿 - Qiita	Gitまとめ	https://qiita.com/ogamasa4466/items/8369dac77a9710767f35	そのままコミットを積み重ねることもできるが、次にチェックアウトしたときに目印がないため戻ってこれなくなる。	2021-11-29 23:59:50
技術ブログ	Developers.IO	Step Functionsステートマシンの実行のイベントソースを確認する	https://dev.classmethod.jp/articles/check-the-event-source-of-step-functions-state-machine-execution/	awsstepfunctions	2021-11-29 14:53:36
海外TECH	Ars Technica	James Webb Space Telescope cleared for late December launch	https://arstechnica.com/?p=1816596	ariane	2021-11-29 14:45:40
海外TECH	MakeUseOf	How to Change Your Twitter Password	https://www.makeuseof.com/how-to-change-twitter-password/	account	2021-11-29 14:45:12
海外TECH	MakeUseOf	Is Windows 11 Good for Developers?	https://www.makeuseof.com/is-windows-11-good-for-developers/	windows	2021-11-29 14:30:12
海外TECH	MakeUseOf	Unbalanced vs. Balanced Audio – What’s the Difference?	https://www.makeuseof.com/unbalanced-vs-balanced-audio-differences/	different	2021-11-29 14:15:11
海外TECH	DEV Community	Day 2 - Basic CSS | #100DaysOfCode	https://dev.to/jannatinnaim/day-2-basic-css-100daysofcode-17d9	Day Basic CSS DaysOfCode What did I learn today Completed the Basic CSS from FreeCodeCamp CSS gives websites their looks It s kinda like makeup but on steroids I ve only scratched the surface of it and I know there s so much to learn about CSS What problems did I face I didn t face any problems today either I m somewhat familiar with CSS which helped me get through the basics of it Although this might change very soon What do I want to do tomorrow Tomorrow I take on the Applied Design course This one seems kinda challenging and probably is Excited for it How was the experience so far So far so good I got the basics of HTML and CSS and now comes their practical uses So hoping for the best Useful LinksFree Code CampGitHub	2021-11-29 14:38:37
海外TECH	DEV Community	Memory Management in Javascript	https://dev.to/ohdylan/memory-management-in-javascript-4aod	Memory Management in JavascriptJavascript is a high level language that has GC garbage collections being done by the modern browsers Javascript engines This gives Javascript developers an impression that neither they need to know what is happening behind the scene nor doing something to improve the memory management of their Javascript app One of the reasons that lower level languages such as C language are faster and more efficient is because we can control the GC manually therefore they are more optimised and efficient in memory management There are three main parts of Javascript memory management consists of When we assign a value to a variable it will automatically allocate an available memory piece to store the value and with reference linked to this variable This variable is then used in the script When variable is not in used anymore or the reference was removed the memory in heaps will automatically be freed to prevent memory leaks Javascript is using Mark and Sweep algorithm for memory management as the points above Basically it will mark those memory reference that are in used by the script and sweep the rest off var apple color red category fruits var apple color red category fruits apple There might be cases where garbage collection is not able to free up those unused memory and causes memory leaks We as a Javascript developer could do something to try preventing them Three of the most commonly seen causes of memory leaks are Event ListenersEvent listeners will automatically be removed when the DOM element is detached from the DOM tree and with no more reference to it in Javascript However older browser such as IE will not be able to handle this properly Besides we should also plan the usage of our event listeners carefully because they are not in used most of the time until events are triggered and they take up memory when those DOM elements are active Global VariablesThere is always a Global Object in Javascript for example the window object in browser and the global object in Node js We should try to avoid using global variables as they will always exist when the global execution context is still in the stacks This global execution context is created before any code is executed and therefore these global variables will always be attached and not being garbage collected Again planning is important Try to use local variables defined with let and const not var if we declare with var it will be part of the Global Object within the blocked scope for example in functions The local variables in functions are automatically cleared off when the function call is popped off from the stack Things that continuously running in the backgroundWe should also be careful when we use functions such as setInterval When we use a variable in the callback function this variable will always be attached and not getting cleared off Conclusion Planning before executing even the logic of assiging variables This will help improving the performance of your app especially when it scales up	2021-11-29 14:26:49
海外TECH	DEV Community	Legacy: alarming symptoms and problems	https://dev.to/typeable/legacy-alarming-symptoms-and-problems-5820	Legacy alarming symptoms and problemsAuthor Victoriia Zaripova IntroductionThe purpose of this post is to give non IT specialists a basic insight into the hazards of obsolete computer systems and code and the way they may harm the business You might have heard the word legacy usually with a negative connotation from the technical staff This term is used to denote the methods technologies and computer systems or application software that are declared to be obsolete due to some reason However does this legacy always have negative implications for the business is it mandatory to get rid of it and how can you understand that it really creates problems As a rule the developers analysts testers and support staff are those who face the legacy issues most often which is evidenced by the broad experience of our own team For end users these issues usually remain under the bonnet and for CEOs they are concealed behind report figures without showing any logic behind them Basically the situation on the whole reminds of the permanent tuning of outside appearance and interior in a car where the engine is at its last gasp but the passengers suspect nothing Sooner or later this automotive marvel is bound to die somewhere between point A and point B but until that time the car will make a positive impression especially if the passenger compartment is extremely comfortable and the suspension or speaking straight out the frontline allows driving over potholes almost smoothly However there is also no point in replacing your tried and tested tractor with a trendy smart right on the spot Everything depends on the objectives and current state of the issue How can you understand that legacy is a hindrance Here is the list of alarming symptoms and issues you can notice even without being a professional Lack of well defined and clear documentation for the supported business processesPerhaps now the documentation seems to be of no importance since each of your employees is a real pro who can explain the entire business process from A to Z at any moment and knows the information system they are using inside out However the real life experience usually shows that this is far from being the case Moreover even the terms used by the personnel in different departments differ significantly The most basic example is the attempt to build the business process for supply agreements approval Lawyers treat the term “agreement quite differently from accountants and both departments focus on entirely different stages of the agreement approval Today businesses are more willing to recognize the value of transparent and well organized business processes and you ll have little difficulty in finding a post on the advantages of this approach Here is an example Benefits of BPM Massive Advantages of Business Process Management Besides this article is also notable for the studies it s based on in particular the study of stating that the outbreak of COVID made businesses invest more in the business process automation and altered their assessment of how important it is to change the obsolete processes Rigidity in improvementsDue to some reasons you are not able to integrate easily and quickly with the leading services timely scale up or flexibly modify the software and consequently always miss the boat of market opportunities Just believe this is not a chain of tragic accidents but a disturbing symptom This symptom is especially clearly seen in governmental institutions where rigidity is embedded in the work format and where all changes require long term approval For instance excess expenses of the US government for the IT infrastructure in over billion dollars triggered the internal investigation showing that obsolete software is the key issue Nevertheless commercial companies whose way of operation implies flexibility and openness to new technologies also suffer from the legacy Airline companies banks insurance companies and retailers sooner or later turn out to be unable to overcome the rigidity of obsolete software As a result their operation becomes unstable they are not able to bring new products and services to market or even stably support the existing ones For example in August Delta Air Lines faced an unexpected failure of the booking check in and boarding systems which always seemed to be reliable which resulted in an hours long downtime and cancellation of more than flights This and other cases are described in the post Legacy systems are problems for boardrooms not computer geeks Financial Times Jan Low spirits in the IT team and loss of users loyaltyOne would think that the legacy cannot affect the team morale There is no secret as any modification of legacy systems resembles a patch on the A bomb most probably it won t go off but you wouldn t like to touch it again if you can help it Specialists in obsolete languages and technologies don t come cheap one has only to think about the YK problem Novices on the other hand try to patch the old environment with something new so with time all this becomes a monstrous zoo of technologies where not every specialist would dare to plunge As the result the users complain more and more about the problems and the product development is hindered Moreover the personnel are more likely to leave as they ll be demotivated and not willing to dig through the problems of obsolete monstrous code with documentation missing or passed over as verbal folklore Of course no one is indispensable but you should remember that selection and adaptation of a new staff member come at a price and the more complex and intricate the project is the more time it will take the new employee to become up to speed while being paid for work with the old code Meanwhile the rest of the team will have to solve business critical problems And now imagine that dramatic market changes and they ve always been dramatic recently require an immediate response It s not necessary to imagine for yourself you can just read what situation the businesses are facing today The coronavirus COVID business impact Standard solutionsThus we ve found out that legacy is not just a problem for the IT department but also a potential threat to the company stability and growth Let s consider standard solutions for this situation Ignore this path can be costly if you already see the problems listed above but it can be optimal in some cases In the long run if the business pathway is unchangeable it s better to rely on the trusted comrade in arms with whom you went through fire and water Replace it with completely new software sometimes this path is the only possible solution because the legacy like a disease can infect the environment very quickly Replace gradually component wise this way is usually the revolution from below when the IT department systematically performs refactoring of the home system but it usually requires almost boundless tenacity and consistency Reengineering of business processes and the software this path is perhaps the most radical practical and effective but it s labour intensive and needs the deliberate commitment of the management ConclusionAs you can see legacy can do harm to the business not only to the programmers nerves You can deal with the legacy in different ways and different ways will work for specific cases In our next post we ll describe in more detail when and what way should be selected and will also tell how technical tools can help you to work with the legacy	2021-11-29 14:21:08
海外TECH	DEV Community	Why Not to Become a Data Engineer	https://dev.to/seattledataguy/why-not-to-become-a-data-engineer-44ke	Why Not to Become a Data EngineerAs companies struggle to manage their massive and complex data sets the necessity for data engineers has become more apparent Data engineering became the fastest growing single job in with  percent year on year growth and there s little reason to believe demand for data engineers will slow soon  As with all careers though there are pros and cons to data engineering  Here s what you need to know about this up and coming job field and some of the reasons you may or may not want to pursue it What Is a Data Engineer Data engineers move remodel and manage data sets from s if not s of internal company applications so analysts and data scientists don t need to spend their time constantly pulling data sets They may also create a core layer of data that lets different data sources connect to it to get more information or context  Data engineers spend their time developing data pipelines managing data warehouses and maintaining all the various infrastructure components they develop along the way These specialists are usually the first people to handle data They process the data so it s useful for everyone not just the systems that store it There are obvious reasons to become a data engineer like a high salary and numerous opportunities due to limited competition within the job market but we re not focusing on those today Instead let s ask the question why not to become a data engineer What Skills Does a Data Engineer Need To assist you as a new data engineer I have created a skill set pyramid that can be thought of as a hierarchy of skill set needs This will help you focus on the skills you should learn first allowing you to build a solid foundation as you move on to more specific skills Just remember the way you learn each step of the pyramid does not need to be overly rigid or stay in a strict order You can layer each step helping you progress as you learn Let s get started Reasons Not to Become a Data EngineerDespite being an in demand career that promises high earnings and job security becoming a data engineer isn t for everyone As with most professions it s important to consider your own skills talents and personality before choosing a career in data engineering Here are some of the reasons you may not want to become a data engineer You re Letting Money Drive Your Career ChoiceWhile money is certainly important it shouldn t be the driving force behind your career choice Assuming you re planning to work in the tech field anyway it s better to choose a role you will genuinely enjoy even if the earnings could be a bit lower  A difference of or even in earnings won t drastically impact the lifestyle of a highly paid tech worker especially once taxes are taken into account The level of enjoyment you derive from your work on the other hand will affect your overall happiness and satisfaction in your professional life The average data engineer earns  per year which is significantly above the overall US average of The financial benefits of becoming a data engineer however become much less clear when compared to other jobs in the tech field The average software engineer for example can expect to make about As you can see the difference between a software engineer s salary and a data engineer s salary is fairly negligible If software engineering would be a more fulfilling job for you the slightly higher average salary isn t worth going into data engineering You Don t Enjoy the Engineering MindsetData engineering requires you to adopt and deploy an engineering mindset which some people can find rather constrictive  Because data engineers often need to create pieces of infrastructure that other engineers can maintain in the future they must work within a strict set of rules and standards These rules are extremely important but can also seem burdensome to those who prefer more creative freedom in their projects This isn t to say of course that there aren t creative aspects to the engineering mindset High level problem solving for instance often requires engineers to develop creative solutions Likewise engineers use creative problem solving skills to continuously improve their projects In order to be a successful data engineer you ll need to be able to balance your creative impulses with the rigorous mindset of an engineering professional You Aren t Flexible EnoughOne of the most interesting aspects of being a data engineer is the flexibility and lack of definition for the role  Because of its highly interdisciplinary nature data engineering combines elements of data analysis programming modeling machine learning and many other specific skills  Becoming a professional data engineer requires you to flexibly adapt and deploy these various skills as needed for the specific project you re working on The downside of this interdisciplinary approach to data engineering is that it requires more flexibility than most other tech jobs In your data engineering career you may take on drastically different roles at different companies while maintaining the same job title If you prefer to have a well defined set role you likely won t enjoy the somewhat chaotic world of data engineering You Don t Enjoy Continuous LearningA final reason you may not want to become a data engineer is that you don t enjoy the process of continuous learning Technologies are constantly shifting and evolving requiring data engineers to update their skills on an ongoing basis The cloud data warehouse tool Snowflake for example has seen substantial growth over the last years as companies have embraced cloud computing As trends like this emerge data scientists must learn to use new tools and technologies to stay at the cutting edge If one of your career goals is to eventually stop learning and rest on your laurels data engineering won t be a good fit for you Indeed this is true of almost all roles in the tech industry Continuous learning is crucial for staying on top of trends and technologies and even the most seasoned experts must pursue ongoing education to remain relevant Failure to stay on top of new developments practically guarantees that your skills will eventually become outdated While you might be able to work with older technologies at a handful of companies your career options will narrow significantly when you stop updating your skills Conclusion Know YourselfAs you can see knowing yourself and your preferences is essential to deciding whether a career in data engineering is right for you In addition to knowing what you like to do in terms of specific tasks and working conditions it s also important to consider your own personality  Data engineering is a suitable role for people who prefer to work in the background within a company rather than directly driving conversations with management using data insights If you prefer that more extroverted side of data though you may enjoy a role as a data scientist Overall becoming a data engineer is a great career choice for people who love detail following engineering guidelines and building pipelines that allow raw data to be turned into actionable insights  As mentioned earlier a career in data engineering also offers excellent earning potential and strong job security With that said the job isn t for everyone If some of the reasons detailed above seem to describe you it may be a good idea to give data engineering a second thought and explore other tech careers that could fit you better If you want to read watch more about data engineering then check out the links below Data Engineer Vs Analytics Engineer Vs AnalystWhy Migrate To The Modern Data Stack And Where To Start Great Data Engineering Tools For My Favorite Data Engineering Tools SQL Tips For Data ScientistsWhat Are The Benefits Of Cloud Data Warehousing And Why You Should Migrate	2021-11-29 14:16:24
海外TECH	DEV Community	Auto Rename Tag	https://dev.to/larrocax/auto-rename-tag-1b9e	Auto Rename Tag Auto Rename Tag is an extension created for html that changes the ending of tag automatically only when you change the start of itAUTO RENAME TAG	2021-11-29 14:08:15
海外TECH	DEV Community	JavaScript News and Updates of November 2021	https://dev.to/plazarev/javascript-news-and-updates-of-november-2021-1li6	JavaScript News and Updates of November Hello everyone Welcome to a new edition of my monthly news digest dedicated to the latest developments in JavaScript The last month of autumn brought several exciting releases and useful info for the web community This time you will learn about the latest programming trends from the State of the Octoverse survey become familiar with a new product and updates from DHTMLX estimate changes in Angular and TypeScript get a foretaste of new capabilities in ASP NET Core and find out how JS now can be used in Excel Besides I also prepared a pack of articles with useful guides and tips on various JavaScript issues Let s roll New Tools and Updates Key Takeaways from State of the Octoverse It is time to explore key trends in the software development world highlighted in the latest edition of GitHub s State of the Octoverse In this popular annual survey includes valuable insights based not only on traditional analysis of the platform s repositories but also on responses from more than developers The response to a typical question on the most popular programming language remains the same during the past several years It is JavaScript followed by Python nd and Java rd Here we can also mention that TypeScript retained its position in the top while PHP dropped from rd to th place compared to The survey also includes some other interesting facts For instance more than million developers joined GitHub in increasing the total number of GitHub users to million The productivity of the dev community is now comparable with prepandemic levels Almost half of the interviewed developers want to have a hybrid working schedule home office after the pandemic is over Check out the full report to get more useful information from GitHub What s New in Angular Angular is one of the most well known tools in the JavaScript ecosystem Despite its complexity this framework still remains a preferred choice for many programmers especially for those who work on enterprise scale apps The Angular development team from Google continues working on the improvement of this product to keep it competitive with other popular JS frameworks Early this month Angular was finally updated to version This major update comes with a range of useful changes and enhancements for empowering the coding capabilities of web developers The most notable goodies of this release are the removal of the View Engine modernized Angular Package Format APF simplified API for dynamic creation of components and support for persistent build cache Learn more about these and other novelties introduced in v by visiting the Angular blog Introducing DHTMLX Kanban Board vDHTMLX is well known in the web development community for providing high quality JavaScript libraries for various business purposes Recently the company has expanded the product line of JavaScript for project management with a new promising tool JavaScript Kanban board It is written in pure JS and CSS to cover all needs of developers in the workflow visualization DHTMLX Kanban has an intuitive drag and drop interface including three main parts toolbar board with cards and editor All these elements can be easily configured and customized to meet specific project requirements JavaScript Kanbans built with DHTMLX can be complemented with numerous useful features such as filtering amp searching swimlanes setting task priority adding attachments tracking of time and deadlines and much more Numerous localization options help to adjust the Kanban interface to any location This Kanban library is also notable for its high compatibility It can be integrated with popular JS frameworks and any server side technology Go and Node js backends are included by default But more interestingly developers have an opportunity to combine the Kanban component with other popular DHTMLX products namely Gantt and Scheduler Thus devs get everything they need to build a multifunctional solution for project management with DHTMLX If you are interested to learn more detailed information about DHTMLX Kanban read the release article New NET Update Boosts ASP NET Core CapabilitiesMicrosoft rolled out a long awaited major update of the NET cross platform development platform to version This release includes multiple features and improvements for the whole NET architecture including ASP NET Core This performant web framework is a successor to ASP NET that allows building feature packed UIs IoT apps and backend services From now on ASP NET Core supports many useful features such as hot reload minimal APIs asynchronous data streaming null state analysis JS modules and more Moreover single page applications based on ASP NET Core now have a more flexible pattern that can be utilized with other popular JS frameworks Find more details on new additions to ASP NET Core in this blog post JavaScript is Now Available in ExcelExcel is probably the first thing that comes to mind when talking about software solutions for working with tabular data At some point almost every PC user resorts to this tool and its super handy formulas Moreover Excel now also supports JavaScript This month Microsoft released a new JavaScript API that will expand the customization capabilities of developers with Excel It will be possible to create custom data types and related functions within Excel or extend existing ones for achieving various business goals Learn more about this novelty in this blog post Meet Minor Updates of DHTMLX ComponentsIf you want to close the issue of convenient editing and formatting data in a web app the new DHTMLX Spreadsheet is exactly what you need The most notable part of this release is the appearance of several new types of Excel functions expanding the list of available formulas from to The DHTMLX development team also added support for boolean operators and a new default number format Date In addition end users now can easily regulate the size of spreadsheet rows right from the UI and adjust the positioning of text in cells with the new Vertical Align button Want to learn more Here is the full release article Moreover web developers now can also take advantage of DHTMLX Vault This JavaScript file uploader was enriched with important features inline editing keyboard navigation and the ability to disable file preview This blog post offers more details on these features Highlighting TypeScript TypeScript is justly regarded as a promising technology that may one day reach the level of JavaScript in popularity or even higher That is why Microsoft dedicates significant efforts to unleash the full potential of this programming language The recent TypeScript update to version is another step in this direction With a new utility type Awaited and modified Promise object developers get greater opportunities for asynchronous programming Starting from v built in types can be updated separately from the compiler It is also possible to use template string types as discriminants in unions and disable unused imports Two EcmaScript proposals namely Ergonomic brand checks and Import assertions were also implemented It was also planned to include the ESM ECMAScript modules support for Node js in this update but it was temporarily removed due to some implementation issues To get more details on this release pay a visit to the Microsoft blog Useful Tips and Articles Using React Hooks in Web ApplicationsIntroduced in v hooks has become a real game changer for programmers who use React framework for building web applications They give access to the state of a component and other capabilities of React without writing classes Hooks allow writing concise reusable and easy to debug code If you want to deepen your understanding of React hooks explore their practical application and learn how to create custom hooks check out this useful article Avoiding Common Mistakes with JavaScript PromisesSometimes developers get carried away with using too many complex nested callbacks in their code It may lead to a serious issue known as callback hell that makes code unmanageable But fortunately JavaScript has a special Promise object that helps to avoid this problem by providing an effective way for working with asynchronous operations But when using JS promises something can also go wrong The author of this article describes five common mistakes in utilizing JavaScript promises and how to get rid of them in your coding practice How to Implement Microservices in Node jsUsage of microservices can be considered as an alternative to a standard monolithic approach in web application architecture While a monolithic app comes as a single unit solutions based on microservices are divided into multiple independent parts The implication here is that any changes introduced in the monolithic codebase affect the whole system i e a new version of the product should be released The microservice architecture does not have this problem but like any technology it also has some drawbacks This article offers a deeper insight into using microservices their pros and cons and a guide on implementing this type of architecture with Node js Creating a Blockchain with JavaScriptIn recent years the whole world of high technologies has been buzzing about blockchain In essence this innovative technology is designed for securely storing any kind of data It became the heart of almost all cryptocurrencies The demand for blockchain developers is skyrocketing so you can make your first steps in this field right now The YouTube channel Simply Explained provides a great collection of videos that explain the main operating principles of blockchains and help to build a simple version of your own blockchain with JavaScript Dealing with Trojan Source Attacks in JavaScript CodeThis month cyber security researchers from the University of Cambridge revealed a remarkable report dedicated to a new type of source code attack and supply chain attack named Trojan Source This technique exploits Unicode based bidirectional control characters to inject malware into source code comments The main issue here is that these harmful elements are very unlikely to be discovered during the code review Thus it is entirely possible that you can get in trouble without suspecting a thing by simply copying benign looking code from StackOverflow or GitHub This article offers useful recommendations on how to prevent Trojan Source attacks using ESLint	2021-11-29 14:07:10
海外TECH	DEV Community	Getting your HTTP Cache-Control headers right	https://dev.to/imkevdev/getting-your-http-cache-control-headers-right-32m9	Getting your HTTP Cache Control headers rightCross posted from Caching plays a fundamental role in performance What s quicker than a fast request No request Getting your caching strategy right can make a huge difference to your users both repeat and first time There are only two hard things in Computer Science cache invalidation and naming things Phil Karlton years later this well known saying still holds true and while I cannot help you with the naming I want to share what I know about caching to make it easier for you to decide on a caching strategy Disclaimer The scope of this article isn t to serve as a comprehensive guide to all possible caching strategies and how they work there s already plenty of content like that around My goal is to provide you with a reference which you could use to answer the question How should I cache this resource What is caching A cache is a store where you could put a resource This could be done to avoid having to recalculate an expensive computation or to place the content closer to the user In websites this is dictated by the Cache Control header which is defined in the HTTP specification Note The Expires header is no longer needed as its behavior is covered by the Cache Control header Private and shared cachesIn addition to caching in your browser if your content is behind a CDN then your cache control headers influence how the CDN caches your content on the edge Browser cache is referred to as a private cache while a CDN cache is referred to as a shared cache The cacheability of a resource is set using the directives below public Any cache may store the response including a CDN private The response is intended for a single user and should only be stored by the browser cache no store Should not be stored on any cache DemoTo test the different cache control headers I have created a repository containing a simple NodeJS server Please feel free to explore the source code on GitHub and run the application locally Static assetsStatic assets refer to files whose contents do not change and are not generated on request This includes scripts stylesheets and images As these files are generated at build time most modern build tools can assign a unique hash to each file This hash serves as a unique fingerprint for each version of the file and is included in the resource s URL This could be in the form of a query string parameter e g app js v cd or filename e g index ead js Having a unique URL means that you can cache these assets for a very long time even up to one year cache control max age When the website is redeployed and the contents of one of the source files have changed then it will be assigned a new URL and create a new cache entry If the files are served through a CDN then the CDN will cache this file Most CDNs will purge the old files on each redeployment Freshness Guaranteed Performance First user to request the file will receive it from the origin server Every other user will receive a cached copy Caching the HTML pageOne of the major headaches with caching is your HTML page Generally speaking your HTML page will make requests for other resources which are needed to render the page such as CSS images and JavaScript files Whenever your website is redeployed it will update the references to the static assets within the HTML document lt link rel stylesheet href style v css gt becomes lt link rel stylesheet href style v css gt So if the HTML document is cached users with a cached copy will request the old stylesheet style v css which no longer exists on the origin server So while style v css is likely to be cached on the user s browser because of its long expiry it is possible that some users encounter a broken website too If the cached resource style v css is removed from the cache before the cached HTML resource the user will see a broken layout To complicate matters your HTML may also contain server side rendered content retrieved from a CMS If the content is updated on the CMS the cached HTML is now stale ScenariosWhen deciding your caching strategy it is usually a trade off between performance and freshness Instead of explaining the different cache control directives and their applications I will be describing some real life scenarios I worked with and how I would set my cache control headers for that type of website BlogIf you are looking to cache your blog the chances are that the content is not time sensitive and you would prioritize performance over freshness Users are more likely to go directly to the article page instead of navigating through the website If they revisit your blog they are likely to return when a new article is published that is after the cache has expired The CSS and JavaScript files probably do not change that often either cache control public max age stale while revalidate The blog you re reading uses a public max age and stale while revalidate combination By applying a max age of minutes you can cache the page for the duration of the user s session If they leave the page and return within minutes it would load instantly The public directive states that the resource may be cached on both private and shared caches Therefore if the resource has expired in the user s browser cache it would request it from the CDN The CDN may have the resource cached and serve it instantly If it has expired on the CDN then it would fetch it from the origin and update the caches Using stale while revalidate means that the resource can be served stale for an additional seconds after it has expired while it is being revalidated In my specific case I am able to cache the HTML file rather aggressively as I ship very little JavaScript none of which is critical to the user experience and the critical CSS is inlined in the HTML file Depending on how important your subresources are to the user experience you may want to cache for a shorter period If your blog does not work at all without JavaScript then you might want to reduce the max age to avoid the race condition described earlier Freshness Users may receive a worst case minute old response Performance The first user to request the resource will wait for it to be fetched from the origin If the user returns within minutes they will receive a cached response If they return after minutes they will be served a cached copy from the CDN If no users visit the website for minutes the first user to visit the website will wait for the resource to be fetched from the origin News websiteA news website is updated frequently with new articles being added to the home page and the content of some articles updated several times per day cache control public max age stale while revalidate stale if error By applying a combination of max age stale while revalidate and stale if error you can always serve content quickly while minimizing the risk of stale data Resources will be cached on shared or private caches for seconds When the resource expires the cache will serve the stale data for another seconds The stale if error directive indicates that if the origin server does not respond when revalidating the resource the cache may serve the stale data for another minutes Note The stale if error directive isn t widely supported on the browser but is supported on most CDNs Freshness In the worst case the user may receive a minute old response The max age and stale while revalidate values may be adjusted to calibrate this worst case scenario Performance The first user to request the resource will wait for it to be fetched from the origin If the same user or any other user revisits the page within seconds they would get a cached response If they visit the page beyond seconds but within seconds then they would get an instant stale response while the cache is revalidated If they revisit the page beyond seconds then the resource is fetched from the CDN If no user visits the page for minute the next user will fetch the resource from the origin Live eventIf your website is showing a live event and content is updated frequently you want the data to be as fresh as possible An example of a live event may be a sports match showing real time scores or an election results page cache control public no cacheSetting no cache indicates that a cache must not be used for a subsequent request without revalidating it with the origin server This is the equivalent of must revalidate max age Once again setting public will enable your CDN to cache the resource and avoid hitting your origin server for each user request Freshness Users will always receive a fresh resource Performance Each request will incur a network call If the resource has not changed then the payload would only include the response headers Logged in pagesAny page or resource which is only available for a logged in user or contains data specific to a logged in session should not be cached cache control no storeFreshness Users will always receive a fresh resource Performance Each request will be fetched from the origin ConclusionHTTP Cache Control headers remain a cornerstone for good performance When choosing a caching strategy take your time to consider the following Not all resources are equal Measure the performance gains a user would benefit from if you cache a resource Can you get away with serving stale content Identify how likely your cached resources may become out of sync and what your users would experience in that eventuality Recommended readingThere is a lot of content explaining how the different cache control directives work Below are some of my favorite resources on the topic Caching best practices amp max age gotchasLove your cacheCache Control for CiviliansRemix Run Introduction to HTTP CachingCDN Caching Static Site Generation and Server Side RenderingHTTP cachingOrigin Cache ControlDifferent versions of your site can be running at the same timePhoto by Ricardo Resende on Unsplash	2021-11-29 14:04:12
海外TECH	DEV Community	HLS Interstitials in Safari	https://dev.to/video/hls-interstitials-on-safari-go7	HLS Interstitials in Safari IntroductionAs mentioned in our previous post HLS interstitials doesn t work natively in Safari or in any other HTML player but that doesn t mean that it can t work Interstitial playback on Apple devices is accomplished using two players GettingStartedWithHLSInterstitials pdf p This is a common technique used in may AVOD services today albeit without the ads being part of the HLS manifest the client creates two lt video gt elements and puts them on top of each other and simply switch between which lt video gt element is visible This means that the only thing we are limited by is our ability to read the HLS interstitials from the manifest In this post we will focus on how to achieve this in Safari and in a future post we will show how to accomplish this using the excellent hls js library Reading the manifestSince HLS interstitials are added using the existing EXT X DATERANGE tag we can use the built in browser APIs to read them In Safari they have achieved this using the TextTrack interface listen to the addtrack event to detect when a texttrack is added to the video elementvideo textTracks addEventListener addtrack track TrackEvent gt check if the track is of kind metadata this is where Safari adds any EXT X DATERANGE information if track amp amp track kind metadata by default the track is disabled set it to hidden to allow it to start parsing any EXT X DATERANGE track mode hidden track cues will now be populated with all available EXT X DATERANGES in the entire manifest track addEventListener cuechange async evt gt if this event is dispatched the track activeCues property will contain the active EXT X DATERANGE The EXT X DATERANGEs will show up in the cues activeCues field of the metadata text track as DataCue the specification for those cues are just in draft so they are subject to change The relevant part for HLS interstitials is the following value key X ASSET LIST data lt url to X ASSET LIST gt startTime Note that each X attribute of the daterange will show up as separate cues so if you want full support for HLS interstitials you need to read from multiple cues to get a complete HLS interstitial configuration Using this technique we were able to create this simple PoC demo show casing how HLS interstitials can look today in Safari The demo contains a preroll and two midrolls one at s and one at m s LearningsWhen implementing this little PoC we discovered two specific things that one needs to workaround to get this to work The metadata track becomes disabled When the interstitial video is playing the master video will disable the metadata track which means that we can no longer read the EXT X DATERANGEs from the manifest Luckily the browser does dispatch the onchange event on the textTracks so we can force enable it if needed Safari reads a PDT of as falseIf you set the PDT of the HLS to EXT X PROGRAM DATE TIME T Z Safari will not set the startTime field of the EXT X DATERANGE cue correctly it will set all startTime fields to A simple workaround if you control the HLS is to set it to eg EXT X PROGRAM DATE TIME T Z About Eyevinn TechnologyEyevinn Technology is an independent consultant firm specialized in video and streaming Independent in a way that we are not commercially tied to any platform or technology vendor At Eyevinn every software developer consultant has a dedicated budget reserved for open source development and contribution to the open source community This give us room for innovation team building and personal competence development And also gives us as a company a way to contribute back to the open source community Want to know more about Eyevinn and how it is to work here Contact us at work eyevinn se	2021-11-29 14:01:51
Apple	AppleInsider - Frontpage News	Jack Dorsey reportedly preparing to step down as Twitter CEO	https://appleinsider.com/articles/21/11/29/jack-dorsey-reportedly-preparing-to-step-down-as-twitter-ceo?utm_medium=rss	Jack Dorsey reportedly preparing to step down as Twitter CEOJack Dorsey the CEO and co founder of Twitter is believed to be preparing to step away from his role as the head of the micro blogging app As the head of Twitter Jack Dorsey has had to weather many controversies on the site but it seems the next one will primarily feature him It is thought that the CEO will soon be stepping down According to anonymous sources of CNBC on Monday Dorsey is expected to step down from his position Few details are provided by the sources such as when it would be announced or the reasons behind the move Read more	2021-11-29 14:45:44
Apple	AppleInsider - Frontpage News	HomeKit smart plug & garage door roundup, Twinkly lights, Aqara G3 on HomeKit Insider	https://appleinsider.com/articles/21/11/29/homekit-smart-plug-garage-door-roundup-twinkly-lights-aqara-g3-on-homekit-insider?utm_medium=rss	HomeKit smart plug amp garage door roundup Twinkly lights Aqara G on HomeKit InsiderOn the latest episode of the HomeKit Insider podcast your hosts discuss Twinkly s newfound HomeKit support the Aqara G Hub and we roundup our favorite smart plugs and garage door openers Twinkly making of various holiday lighting products has just updated their devices via new firmware to bring native HomeKit support This includes various styles such as standard light strands curtain lights flexible strips and bundles of lights All just in time for the holidays Aqara also announced its new device the Aqara G Hub is available in the US This camera hub combo supports degree video via the Aqara app If you choose not to use the Aqara app you can use HomeKit Secure Video with recordings saved directly to iCloud Read more	2021-11-29 14:33:20
Apple	AppleInsider - Frontpage News	B&H Cyber Monday Sale: Mac hardware as low as $629, 14-inch MacBook Pro $1,799, $100 off iPads	https://appleinsider.com/articles/21/11/29/bh-cyber-monday-sale-mac-hardware-as-low-as-629-14-inch-macbook-pro-1799-and-in-stock-100-off-ipads?utm_medium=rss	B amp H Cyber Monday Sale Mac hardware as low as inch MacBook Pro off iPadsB amp H s Cyber Monday Apple Sale is live with triple digit discounts on the iPad Pro Mac mini MacBook Air iMac and even the new inch MacBook Pro Plus save on sales tax with Payboo Newest Cyber Monday dealsCyber Monday steals on Apple products are going on now at Apple Authorized Reseller B amp H Photo From Apple s M Mac mini for to off this inch MacBook Pro there s a wide selection of bargains to choose from for easy holiday gift giving Read more	2021-11-29 14:21:57
Apple	AppleInsider - Frontpage News	HexGaming Ultimate Controller review: competition grade for iOS, iPadOS, and macOS	https://appleinsider.com/articles/21/11/28/hexgaming-ultimate-controller-review-a-competition-level-controller-that-works-with-apple-gear?utm_medium=rss	HexGaming Ultimate Controller review competition grade for iOS iPadOS and macOSThe HexGaming Ultimate Controller lives up to its name with a fully customizable design swappable joysticks and programmable paddle buttons It also happens to be compatible with Apple s well connected ecosystem The front of our customized HexGaming Ultimate ControllerAn upgraded PS controller Read more	2021-11-29 14:29:37
Apple	AppleInsider - Frontpage News	Amazon Cyber Monday deals are live: Up to 70% off Beats, routers, OLED TVs, Apple hardware, Sony headphones	https://appleinsider.com/articles/21/11/28/amazon-cyber-monday-deals-are-live-up-to-70-off-beats-routers-oled-tvs-apple-hardware-sony-headphones?utm_medium=rss	Amazon Cyber Monday deals are live Up to off Beats routers OLED TVs Apple hardware Sony headphonesAmazon s Cyber Monday deals start now with discounts of up to off everything from K OLED TVs to Apple AirPods Find out which deals are a must with even better than Black Friday pricing Amazon Cyber Monday Sale starts nowHundreds of Cyber Monday deals have launched at Amazon ahead of what could be the biggest shopping day of the year offering shoppers significant savings in nearly every vertical The AppleInsider Deals Team has been hard at work analyzing the latest offers to handpick the very best bargains from the flash sale Read more	2021-11-29 14:57:26
海外TECH	Engadget	Apple's second-gen AirPods are on sale for $100 right now	https://www.engadget.com/apple-second-generation-airpods-sale-cyber-monday-good-deal-144841170.html?src=rss	Apple x s second gen AirPods are on sale for right nowIf you re an iPhone Mac iPad and or Apple Watch user who s on the hunt for new earphones this Cyber Monday it s worth checking out deals on AirPods The second generation AirPods are currently on sale for on Amazon a saving of The price is on the product page but a coupon is applied at checkout Buy Apple AirPods nd gen at Amazon We gave the second gen AirPods a score of in our review giving them props for maintaining the same solid battery life as the first version and offering better wireless performance Elsewhere you can also save on the most recent model The third gen Apple AirPods are currently on Amazon after a coupon is applied In total Amazon has reduced the price by We gave the third gen AirPods a score of in our review in part due to the more comfortable design The latest version offers better audio quality and a longer battery life Buy Apple AirPods rd gen at Amazon Get the latest Black Friday and Cyber Monday offers by visiting our deals homepage and following EngadgetDeals on Twitter All products recommended by Engadget are selected by our editorial team independent of our parent company Some of our stories include affiliate links If you buy something through one of these links we may earn an affiliate commission	2021-11-29 14:48:41
海外TECH	Engadget	The Roomba j7+ vacuum hits new all-time low in iRobot's Cyber Monday sale	https://www.engadget.com/the-roomba-j7-vacuum-hits-new-all-time-low-in-i-robots-cyber-monday-sale-141515068.html?src=rss	The Roomba j vacuum hits new all time low in iRobot x s Cyber Monday saleThe holiday shopping season is one of the best times of year to look for a new vacuum ーrobotic or not We ve seen numerous models go on sale before and during Black Friday and now a new Cyber Monday sale has knocked iRobot devices down to new record lows Key among them are the new poop detecting j duo of robot vacuums both of which are off The Roomba j has dropped to while the j which comes with a clean base is down to Those prices are being matched at Best Buy and Wellbots too Buy Roomba j at Amazon Buy Roomba j at Amazon Shop Roomba Cyber Monday sale at Amazon quot Poop detecting quot might sound gimmicky but these robot vacuums have new AI driven computer vision technology that helps them detect obstacles as they clean so they can move around them That means instead of bumping into chair legs and tables these machines will do a better job of cleaning around those permanent fixtures in your home ーand they ll more easily avoid surprise hazards like pet poop And if your new robo vac doesn t avoid your pet s latest mess iRobot s Pet Owner Official Promise yes P O O P ensures that you ll get a new vacuum if such a disaster happens within your first year of ownership Otherwise the j devices are higher end Roombas so they have features like dual multi surface rubber brushes and Imprint Smart Mapping which lets you control which rooms the robot cleans The biggest difference between the j and the j is the inclusion of the clean base on the latter When it returns home to charge the j will automatically empty its bin into the clean base and you ll only have to empty the base about once every two months A number of more affordable Roombas are included in the sale too like the Roomba which remains on sale for This is one of our favorite budget robot vacuums thanks to its good cleaning abilities and easy to use mobile app You can also get the top of the line Roomba the s with the Braava Jet mopping robot for over off bringing it down to Get the latest Black Friday and Cyber Monday offers by visiting our deals homepage and following EngadgetDeals on Twitter All products recommended by Engadget are selected by our editorial team independent of our parent company Some of our stories include affiliate links If you buy something through one of these links we may earn an affiliate commission	2021-11-29 14:15:15
海外科学	NYT > Science	Laszlo Z. Bito, Scientist, Novelist and Philanthropist, Dies at 87	https://www.nytimes.com/2021/11/27/world/europe/laszlo-z-bito-dead.html	Laszlo Z Bito Scientist Novelist and Philanthropist Dies at He fled communist rule in Hungary discovered a treatment for glaucoma in the U S then became an author and a voice against authoritarianism in his homeland	2021-11-29 14:50:03
海外TECH	WIRED	The Best Cyber Monday Deals on Laptops and Home Office Gear	https://www.wired.com/story/best-cyber-monday-laptop-deals-2021	external	2021-11-29 14:52:00
金融	RSS FILE - 日本証券業協会	J-IRISS	https://www.jsda.or.jp/anshin/j-iriss/index.html	iriss	2021-11-29 15:34:00
ニュース	BBC News - Home	Sir Keir Starmer begins reshuffle of Labour shadow cabinet	https://www.bbc.co.uk/news/uk-politics-59461674?at_medium=RSS&at_campaign=KARANGA	leader	2021-11-29 14:08:55
ニュース	BBC News - Home	Storm Arwen: I'm a Celebrity to return on Tuesday following storm damage	https://www.bbc.co.uk/news/entertainment-arts-59459190?at_medium=RSS&at_campaign=KARANGA	arwen	2021-11-29 14:07:36
ニュース	BBC News - Home	Storm Arwen: Third night of no power for thousands	https://www.bbc.co.uk/news/uk-scotland-59457045?at_medium=RSS&at_campaign=KARANGA	beast	2021-11-29 14:45:29
ニュース	BBC News - Home	Magdalena Andersson: Sweden's first female PM returns after resignation	https://www.bbc.co.uk/news/world-europe-59459733?at_medium=RSS&at_campaign=KARANGA	hours	2021-11-29 14:14:47
ニュース	BBC News - Home	Ban MPs from paid consultancy roles, suggests standards committee	https://www.bbc.co.uk/news/uk-politics-59455071?at_medium=RSS&at_campaign=KARANGA	committeethe	2021-11-29 14:25:51
ニュース	BBC News - Home	Khan and Brook announce February fight - then pulled apart by security	https://www.bbc.co.uk/sport/boxing/59443132?at_medium=RSS&at_campaign=KARANGA	february	2021-11-29 14:25:07
ニュース	BBC News - Home	Covid map: Coronavirus cases, deaths, vaccinations by country	https://www.bbc.co.uk/news/world-51235105?at_medium=RSS&at_campaign=KARANGA	countrykey	2021-11-29 14:04:42
ビジネス	不景気.com	岐阜の「関ヶ原カントリークラブ」が民事再生、負債40億円 - 不景気.com	https://www.fukeiki.com/2021/11/sekigahara-country-club.html	岐阜県大垣市	2021-11-29 14:25:59
仮想通貨	BITPRESS（ビットプレス）	ビットバンク、12/3より「チェーンリンク（LINK）」の取扱開始	https://bitpress.jp/count2/3_10_12914	取扱	2021-11-29 23:26:02