Tips, Expertise, Articles and Advice from the Pro's for Your Website or Blog to Succeed
One way to use a Python variable in an external Javascript is to declare the JS variable in the HTML template through the context object, then pass this variable to the external script code :
<script type="text/javascript">
js_var_from_dj = "{{ django_var }}";
</script>
<script src="https://dzone.com{% static "js/js_file.js" %}" type="text/javascript"></script>js_file.js :
In the previous installment, I talked about the Java garbage collector. In this part, I'll discuss the most common memory issue: the memory leak. I focus on managed languages, specifically Java, but I will mention some native code tools which are interesting. A memory leak contributes to heap size, which isn't the most pressing bug in most cases. But when left alone, memory usage can become a problem and, by that point, finding the issue is hard. Unlike a crash dump, where we get a reference to a specific line, a memory leak can remain hidden.
Unfortunately, this often means that memory leaks can carry into production and even cause problems to end users. E.g. This recent story about memory leaks hobbling Apples latest M1 computers. Virtual memory effectively means operating systems can carry memory leaks for a very long time. The performance overhead will be noticeable, though.
For Redux to work correctly, the state must be immutable. This means that whenever we update the Redux state, we have to create a copy of the whole state and set values to fields we want to change. In code, this usually looks like this:
let newState = {
...oldState,
field1: {
...oldState.field1,
field2: "someNewValue"
},
}Some modern object-oriented languages have the concept of indexers, which are properties that allow you to index instances of a class just like arrays by using the [] notation. In this article, I would like to show you how to do it in modern JavaScript.
Here’s an example in C#:
Here's how the end result will look like:
Want to try it? Here's the live demo you can use right away. Also, the full source code is available on GitHub.
One of my latest private projects was Frontend built fully with Vue.js. I wanted to support a group of users and roles, where certain account types would be restricted from entering given pages or seeing some of the components.
While Symfony restrictions are provided out-of-box, Vue.js doesn't have such a built-in mechanism, so I decided to combine a bit of knowledge from Vue.js tutorials and Symfony mechanism.
I have been working on Fintech projects for a long time. While working with business people I have realized that they want to see financial items in a proper business format. One of the most common requirements is they want to input amounts filed in a business format (like comma-separated amounts field by only allowing two decimal points, etc).
I have searched a lot on the internet and didn’t there any complete article or guideline to validate and take input of the amount field properly, and finance clients always want to input/type the amount field in a way where the user can feel that he/she is inputting/typing an amount, not a number or anything else.
Here at Sentry, we like to dogfood our product as much as possible. Sometimes, it results in unusual applications of our product and sometimes these unusual applications pay off in a meaningful way. In this blog post, we’ll examine one such case where we use the Sentry JavaScript SDK to instrument Jest (which runs our frontend test suite) and how we addressed the issues that we found.
We have high-level metrics for how well (or not) our CI is performing. This is useful to get a general sense of the health of the system, however, it does not help when doing a deeper dive into why a system is slow. We decided to instrument our CI jobs at the test runner level in order to get insights into the performance of the individual tests. We needed to be able to see if our test suite was slowing down because we were adding more tests or if it was because we had poor-performing tests.
Large numbers of data and requests from the web can be handled well by responsive APIs. Clients (like your browser) can subscribe to “events” by utilizing the “server-side event” model, which “pushes” available events to the client.
It is not useful in cases with simple CRUD applications, but when dealing with situations with millions of “subscribers”, it is significantly faster than traditional “request-response” architectures.
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Earlier this month the React Team released some updates concerning the release of React 18. These updates include the following:
Do you use BitBucket Pipeline as your CI server? Are you struggling with slow E2E tests in Cypress? Did you know BitBucket Pipeline can run parallel steps? You can use it to distribute your browser tests across several parallel steps to execute end-to-end Cypress tests in a short amount of time.
Distributing tests across parallel steps to spread the workload and run tests faster might be more challenging than you think. The question is how to divide Cypress test files across the parallel jobs in order to ensure the work is distributed evenly? But… is distributing work evenly what you actually want?
While JavaScript frameworks are now vital for web app development, many companies struggle to choose between React and Vue for their projects. The short answer is that there is no clear winner in the general React.js vs. Vue.js debate. Each framework has its pros and cons and is useful for different applications. So, we’ve put together this convenient guide to popular frameworks, to help you better understand the use cases of Vue vs. React and determine which one will work best for your next project.
Both React and Vue are open source JavaScript frameworks that make it easier and faster for developers to build complex user interfaces. Before we get into the React vs. Vue comparison, we’ll give you a brief overview of each one.
On January 27, 2021, Angie Jones of Applitools hosted Brian Douglas, aka "bdougie", a Staff Developer Advocate at GitHub, for a webinar to help you jump into GitHub Actions. You can watch the entire webinar on YouTube. This article goes through the highlights for you.
Angie Jones serves as Senior Director of Test Automation University and as Principal Developer Advocate at Applitools. She tweets at @techgirl1908, and her website here.
This is a 3 part series for unit testing the controller, service, and repository layers in a typical REST architecture. There are many approaches to doing this, I'm sharing a pattern that I find very flexible and hopefully, you can pick up some tips and tricks along the way.
Part 1 — Unit Testing the Controller | Git branch can be found here.
PDF documents are a major part of our digital lives and, in an era where we spend most of our time working inside a web browser, enhancing the PDF experience on the web is crucial for providing a seamless, multi-device experience. As the creators of PDF, this led Adobe to envision Acrobat Web; we embarked on our Acrobat Web journey with the introduction of the Document Cloud PDF Embed API in 2019.
The PDF Embed API offers Adobe’s pixel-perfect PDF viewing on the web with the promise of performance and ease of integration on all major browsers. It also offers UI customization and integration with Adobe Analytics. You can see the Embed API in action here.
Today we’d like to present a blueprint for large Vue JS projects. It uses the new and exciting Vite build tool and Lerna monorepo manager. I’ve built large enterprise projects in a similar way, using Angular, Vue JS, webpack, and rollup. Vite, created by the Vue JS team, looks very promising so I wanted to give it a try.
There are plenty of Vite tutorials and demos, mostly the usual Hello World and Todo apps. But I needed something more useful. I wanted to see whether Vite can replace rollup and webpack in large real-life projects.
Ryan Dahl is a software engineer and the original developer of the Node.js, and the Deno JavaScript and TypeScript runtime. We are glad to have had an opportunity to speak to Ryan about his projects, the main challenges in Deno, hear his thoughts on the future of JavaScript and TypeScript, find more about the third-party Deno ecosystem projects and discuss how he would have changed his approach to Node.js if he could travel back in time!
Evrone: Your new Deno project is quite an impact among developers. What are you doing right now most of the time?
Programming is a tough job, and it needs proper attention and outstanding information about the syntax and logic of language. We all understand that JSON is one of the most powerful ways to transmit data on the web. Still, writing code is a bit tricky. Now, there's no need to waste hours sitting and focusing on your code to detect the error. If you are curious to know why then stay tuned and keep reading this post until the end so that you can know everything!
JavaScript Object Notation, which is generally known as JSON, is a definitive text-based format. It is used to represent structured data based on JavaScript object syntax. Well, commonly it is used for delivering data in web applications, for example, sending data to the client from the server so that it can be shown on a web page, or vice versa. You'll come across it quite frequently, so, in this short article, we are providing you with all you require to work with JSON utilizing JavaScript, comprising parsing JSON so that data within it will be easy to access, and generate.
