teleren/devto huggingface dataset:
What is a servlet?
Published: 2023-05-30 17:28:22



A servlet is a Java class that runs on a web server and handles requests from web clients (such as browsers). A servlet can generate dynamic web content, such as HTML, XML, JSON, etc. A servlet can also interact with databases, files, and other web resources.

## Servlet API 📚

The servlet API is a set of interfaces and classes that define how a servlet communicates with the web server and the web client. The servlet API is part of the Java EE (Enterprise Edition) specification. The servlet API consists of two packages: `javax.servlet` and `javax.servlet.http`.

The `javax.servlet` package contains the core interfaces and classes for servlets, such as `Servlet`, `ServletConfig`, `ServletRequest`, `ServletResponse`, etc.

The `javax.servlet.http` package contains the HTTP-specific interfaces and classes for servlets, such as `HttpServlet`, `HttpServletRequest`, `HttpServletResponse`, etc.

## Life cycle of a servlet 🔄

The life cycle of a servlet describes the stages that a servlet goes through from its creation to its destruction. The life cycle of a servlet can be summarized in three steps:

1. Initialization: The web server loads the servlet class and creates an instance of the servlet. The web server then calls the `init()` method of the servlet to initialize it. The `init()` method is called only once for each servlet instance.
2. Service: The web server invokes the `service()` method of the servlet to handle requests from web clients. The `service()` method can delegate the request to other methods based on the HTTP method (such as `doGet()`, `doPost()`, etc.). The `service()` method is called multiple times for each servlet instance, once for each request.
3. Destruction: The web server calls the `destroy()` method of the servlet to terminate it. The `destroy()` method is called only once for each servlet instance, when the web server decides to unload the servlet (such as when the web server shuts down or when the servlet is idle for a long time).

The following diagram illustrates the life cycle of a servlet:

```mermaid
sequenceDiagram
    participant Web Server
    participant Servlet
    Web Server->>Servlet: load and create
    Servlet->>Web Server: init()
    loop service()
        Web Server->>Servlet: request
        Servlet->>Web Server: response
    end
    Web Server->>Servlet: destroy()
```
6 Websites You’ll Love As A Developer
Tags: webdev, javascript, programming, tutorial
Published: 2023-05-30 17:13:03

If you're looking for a website that specifically focuses on providing assistance and resources for developers, you might find the following website helpful:

**1. [medCode](https://www.medcode.dev/)**
MedCode's Blog – Your Ultimate Destination for Software and Design Insights. Dive into a wealth of knowledge curated specifically for software enthusiasts and design aficionados. From cutting-edge coding techniques to innovative design trends, MedCode's Blog offers invaluable resources to elevate your skills and stay ahead of the curve. Join our community today and unlock the secrets to success in the dynamic worlds of software development and design.


**2. Roadmap.sh**
Roadmap.sh is a website that offers comprehensive technology roadmaps for various career paths in software development and web development. It provides step-by-step guides and resources to help individuals navigate their learning journeys and progress in their chosen field

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/i55bweu8iz6dxp6tdgaj.PNG)

**3. Codepen.io**

CodePen is an online code editor and social development environment that allows developers to write HTML, CSS, and JavaScript code and see the live results in real-time. It provides a collaborative platform for developers to create, experiment, and showcase their front-end web development projects.

With CodePen, you can create and edit HTML, CSS, and JavaScript code directly in your browser. It offers a split-screen view where you can write code in one pane and see the live output in the other. This immediate feedback helps developers quickly iterate and test their code.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/uh7bm1jgli98aatk06v2.PNG)

**4. stackoverflow**
Stack Overflow is a widely-used question-and-answer website for programmers and developers. It serves as a community-driven platform where individuals can ask questions related to programming, software development, and various technologies. Other community members provide answers, solutions, and insights to these questions.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/5e4sms3ub9lzv04mlbb2.PNG)

**5. Readme.io**

Readme.io is a platform that helps developers create beautiful, interactive, and user-friendly documentation for their APIs, SDKs, libraries, or any other software products. It provides tools and features to streamline the process of creating, hosting, and maintaining documentation.
 
![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/gktbpxq2uivwweb9qe93.PNG)

**6. GitBook**
 

GitBook is a platform that allows individuals and teams to create and publish online documentation, ebooks, and knowledge bases. It provides a user-friendly interface and a range of features to streamline the process of writing, collaborating, and distributing content.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/oiu04yus7mnzjtdelvz7.PNG)
App to classify bears with IA 🐻‍❄️🐻
Tags: python, flask, javascript, webdev
Published: 2023-05-30 17:01:45

In 2023 all people are talking about IA. However, it is not totally new. New technologies have been developed by large companies for years, and one of the best known is Open IA.

I have built a web application using Flask to consume services from the client, in this case, the Bear type classification. 

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/pz849wct9804idcncukk.png)

The model used is trained with a DataSet of bear images categorized into 6 classes, each of 50 images.

🏴classes = [polar, spectacled, pardo, panda, malayo, americanBlack]

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/bksyxlc98e3d764uiuzy.png)

The user should drag and drop an image or upload, clicking in the drop area to send the form.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/rwtiuzr99xix3ss8rgnh.png)

Finally, the model makes the prediction and shows you the type of bears with their main characteristics.

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/hgmz7l50hkxaex0p6vbh.png)
It is an open source project and can be modified according to contributions.

Follow me for more content 💻🔬
Link in the bio
https://github.com/SergioSerranoDv/Classification-Model
Generative AI with Azure OpenAI (DALL-E Overview)
Tags: ai, openai, azure, tutorial
Published: 2023-05-30 16:57:34

Hey, there! In this article we'll learn about Generative AI, and how to use the Azure OpenAI service for image generation with DALL-E.

Generative Artificial Intelligence is a type of AI that creates new and original content based on what it has learned from previous data. It can be used to generate text, images, music, and more.  

####**Azure OpenAI**

Azure OpenAI is part of the Azure Cognitive Services that uses generative AI models. In this sense, these are the workloads that we can consider:

- Generating Natural Language.
- Generating Code.
- Generating Images. 

For our Azure OpenAI overview, we'll exemplify this scenario: *Generate images* with DALL-E 2.

## **Exploring Azure OpenAI**

####**Create Azure OpenAI service:**

As a first point, within Azure we'll have to create a new OpenAI resource like any other. 

Here, in addition to the subscription and resource group, we must specify the name, region, and the pricing tier for the new resource.

![Create Azure OpenAI resource](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/2x83c4hn41t2uy075duo.png)

With the service created, here we can see the resource overview, keys & endpoints, and the *Go to Azure OpenAI Studio* option to go to the low-code dashboard.

![Azure OpenAI resource](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/yovohtgezrhjhcwsukke.png)

####**Azure OpenAI Studio:**

And here we have it: The Azure OpenAI portal (https://oai.azure.com/). 

![](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/6uhgiqdv3zrph1p5n02c.png)

To work with DALL-E, in the portal we must go to the `DALL·E 2 playground` section and start generating images with the prompts that we specify:

![](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/7xoyc62i1u9anm6nkz7p.png)

For each image generated these will be our available options:

- Copy prompt.
- Generate a new image with the same prompt.
- Download the image. 
- Show code (to call the model).
- Delete image.

To generate an example of consuming DALL-E in Python, this would be an example of how we can generate the code (from the _Show Code_ option in a generated image):

![](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/a9ir0fwytc9u7dyjw1v6.png)

## **Thanks for reading!**

If you have any questions or ideas in mind, it will be a pleasure to be able to be in communication with you, and together exchange knowledge with each other.

If you would like to learn more about Azure OpenAI, this Microsoft Learn module is a good option: [Introduction to Azure OpenAI Service](https://learn.microsoft.com/en-us/training/modules/explore-azure-openai/). 

See you on [Twitter](https://twitter.com/esDanielGomez) / [LinkedIn](https://www.linkedin.com/in/esdanielgomez).
The biggest enemies of a developer - Part 1
Tags: webdev, programming, learning, beginners
Published: 2023-05-30 16:49:07

## Dealing with frustration and overwhelmness as a Dev


As a developer, there will be a lot of things trying to make your life harder. Whether its your boss or a stupid bug. Its important to cope with all this and not get overwhelmed by it.

I noticed that I wasn't really good at coping with these things. I felt frustrated and overwhelmed a lot. It affected not just my work but also my personal life.

So I researched a little and summarized a couple of points that might help you out.

## How to cope with frustration
Coding is frustrating, ok?
I don't care what anybody says it is not easy to code.

At first, your code runs fine, then you accidentally remove a semicolon and your whole house catches on fire.

But jokes aside. Here is what I found helpful over the years:

### Take a break
I found that 99% of the time when you feel frustrated about programming the best thing you can do is hit the shutdown button and take a break(please don't be like me and save your files first...).

Close your laptop and go for a walk. Play with your kids. Read or do something that would make you forget about that bug you are currently stuck on.

Then when you feel ready get back to it, and you will feel way better.
This lets your mind take a break. This way it can process all that information you dumped there unconsciously.

**Fun fact:** Our unconscious is way more powerful than our conscious.

### Accept it
Remind yourself that frustration is normal.

You are doing hard things that not everybody would be capable to do so it's understandable if you feel frustrated.

Try to view it as a sign that you are getting out of your comfort zone and making progress.
Essentially that's what is it all about - **constantly learning new things**.

### Remember that you are not alone
Come on now, there are a lot of developers out there just like you who got stuck on the same problem. No reason for you to feel frustrated.

Try Googleing the problem.
Somebody probably already encountered it and uploaded the solution for it. If not ask for help on forums such as Stack Overflow(and hope not to get downvoted to depression).

If you don't find a solution online but still manage to solve the problem try to be your own savior and upload it somewhere.
This way the next person won't have to go through what you went through.

Thanks for reading this article. Part 2 is coming soon.
Tiny css separator
Tags: css, typography, html, util
Published: 2023-05-30 10:23:10

Ever had a case where you want to separate some test with a special character. But maybe some content is dynamic. And if not the first is visible - then the separator would be out of place - right? 

This is a little solution I came up with in css using data attributes, empty selector and sibling selectors. 

```css
*:not(:empty) + [data-before]:before {
  content: " " attr(data-before) " ";
}
```

## Use like this

Use it like this with some conditional JSX syntax. 

```jsx
<p>
  {tags && <span>{tags}</span>}
  {date && <span data-before="-">{date}</span>}
</p>
```

This would output **Tagname - May 4:th 2023**  if `tags` is available. And **May 4:th 2023** when no `tags` are available.

## How it works

From left to right top to bottom. The star `*` selector looks at every element. And then the `:not(:empty)` will take any element that has content inside. That is not empty! Then we have the `+` that will select the very next element after that. That element must have a `data-before` attribute. And then we add the `:before` pseudo element. In that before element we add content with spaces before and after and the content from the data attribute `data-before`.

Hope this was useful or educational or something like that.  

Until next time, Cheers!
TEMPORARY FUNCTION IN SQL
Tags: sql, datascience, database
Published: 2023-05-30 16:42:05

##Why use temporary functions?

You might ask “Do we really need functions in SQL?”, 
absolutely yes. Temporary functions are important for several reasons:

•	Organization -- As program grow in complexity, having all the queries in a big chunk increase difficult in understanding the program. Temporary function is almost like a mini-program that we can write separately from our main program, this allows us to reduce a complicated program into smaller, more manageable chunks, which reduces the overall complexity of our program.
•	Reusability -- Once a temporary function is written, it can be called multiple times to the current session. This avoids duplicated queries (“Don’t Repeat Yourself”) and minimizes the probability of copy/paste errors. 


## Example of temporary function

Assume you are a data analyst of a wholesale company, having a database containing tables (Sales and Products). The “Sales” table contains information about sales transactions, including the product ID, quantity, and total price. The “Products” table holds product information, including the product ID, name, price, and discount. You want to know the price of products after discount.

```
CREATE OR REPLACE FUNCTION get_discounted_price(product_id INT)
RETURNS NUMERIC(10, 2)
AS
$$
DECLARE
  original_price NUMERIC(10, 2); 
  discount_rate NUMERIC(5, 2);
  discounted_price NUMERIC(10, 2);
BEGIN
  SELECT price, discount INTO original_price, discount_rate
  FROM Products
  WHERE product_id = product_id;

  discounted_price := original_price * (1 - discount_rate);

  RETURN discounted_price;
END;
$$
LANGUAGE plpgsql;
```
In the above code we create a temporary function named "get_discounted_price" that takes a product ID as a parameter and returns the price after applying the discount for that product.

We utilize our temporary function in our query as follows

```
SELECT product_id, product_name, get_discounted_price(product_id) AS discounted_price
FROM Products;
```

**_REMEMBER_**: Temporary functions are specific to the current session and will be automatically dropped when the session ends.
Basic Workflow in Entity Framework
Tags: webdev, programming, opensource, productivity
Published: 2023-05-30 16:35:51

The Entity Framework (EF) is an object-relational mapping (ORM) framework that simplifies database operations in .NET applications. It provides a way to work with databases using object-oriented principles rather than writing raw SQL queries. Here's a basic workflow when working with Entity Framework:

**1**. Define your entities: Create the classes that represent your database tables. Each class typically corresponds to a table in the database, and the properties of the class represent the columns of the table. You can use attributes or fluent API to define relationships, primary keys, and other database-specific configurations.

**2**. Create a DbContext class: DbContext is the main class in Entity Framework that represents the database session and provides access to the entities. Inherit from the DbContext class and include DbSet properties for each entity you want to work with.

**3**. Configure the connection string: Specify the connection string in your application configuration file (e.g., app.config or web.config). The connection string contains information about the database server, authentication, and other settings required to establish a connection.

**4**. Establish a database connection: Create an instance of your DbContext class. Entity Framework will use the connection string to establish a connection with the database.

**5**. Perform database operations: Use the DbSet properties on your DbContext to perform CRUD (Create, Read, Update, Delete) operations on the entities. For example, you can use methods like Add, Find, Update, Remove, and query methods to interact with the database.

**6**. Save changes: After making changes to your entities, call the SaveChanges method on the DbContext to persist the changes to the database. Entity Framework will generate the appropriate SQL statements based on the modifications you made.

**7**. Handle exceptions: Entity Framework throws exceptions for various scenarios, such as unique constraint violations or database connection errors. Make sure to handle these exceptions appropriately to provide meaningful feedback to the user or handle any necessary rollback or recovery operations.

This is a basic overview of the workflow in Entity Framework. There are additional features and techniques you can use, such as LINQ queries, eager loading, lazy loading, and transaction management, to further enhance your data access capabilities.
What is the entity framework? with Example
Tags: webdev, programming, opensource, aspdotnet
Published: 2023-05-30 16:31:56

Entity Framework is an object-relational mapping (ORM) framework provided by Microsoft. It simplifies the process of working with relational databases by allowing developers to work with database data as objects in their code.

Entity Framework provides a set of tools and libraries that enable developers to create, read, update, and delete data from a database without having to write complex SQL queries. It abstracts the underlying database schema and allows developers to interact with the database using a high-level object-oriented approach.

Here's a simple example to illustrate how Entity Framework works:

Let's say you have a database with a table called "Customers" that has columns like "Id", "Name", and "Email". Using Entity Framework, you can define a corresponding C# class called "Customer" that represents the structure of the table:

```csharp
public class Customer
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
}
```

Next, you would create a DbContext class, which acts as a bridge between your code and the database. The DbContext represents the database context and provides a way to query and interact with the database entities. Here's an example:

```csharp
public class CustomerContext : DbContext
{
    public DbSet<Customer> Customers { get; set; }
}
```

In this example, the DbSet<Customer> property represents the "Customers" table in the database.

To perform database operations, you can create an instance of the CustomerContext and use it to interact with the Customer entities:

```csharp
using (var context = new CustomerContext())
{
    // Insert a new customer
    var newCustomer = new Customer
    {
        Name = "John Doe",
        Email = "johndoe@example.com"
    };
    context.Customers.Add(newCustomer);
    context.SaveChanges();

    // Retrieve customers
    var customers = context.Customers.ToList();
    foreach (var customer in customers)
    {
        Console.WriteLine($"Id: {customer.Id}, Name: {customer.Name}, Email: {customer.Email}");
    }

    // Update a customer
    var existingCustomer = context.Customers.FirstOrDefault(c => c.Id == 1);
    if (existingCustomer != null)
    {
        existingCustomer.Email = "updatedemail@example.com";
        context.SaveChanges();
    }

    // Delete a customer
    var customerToDelete = context.Customers.FirstOrDefault(c => c.Id == 2);
    if (customerToDelete != null)
    {
        context.Customers.Remove(customerToDelete);
        context.SaveChanges();
    }
}
```

In this example, the code creates a new customer, inserts it into the database, retrieves all customers, updates an existing customer's email, and deletes a customer from the database.

Entity Framework handles the mapping between the C# objects and the database tables, as well as the generation of SQL queries necessary to perform the requested operations. It provides a convenient and intuitive way to work with databases, abstracting away the complexities of database access.
Advance SQL tricks.
Tags: sql, datascience, database
Published: 2023-05-30 16:20:37

Certainly! Here are a few advanced SQL tricks that can help you optimize and enhance your SQL queries:

1. Indexing:
   Indexing is a technique used to improve the performance of database queries by creating indexes on specific columns. Indexes allow the database to quickly locate and retrieve the data, especially when working with large tables. By identifying the columns frequently used in WHERE clauses or JOIN conditions, you can create indexes on those columns to speed up query execution.

2. Window Functions:
   Window functions allow you to perform calculations across a set of rows that are related to the current row. They are particularly useful when you need to calculate running totals, rankings, or moving averages.

3. Common Table Expressions (CTEs):
   CTEs allow you to define temporary result sets that can be referenced multiple times within a single query. They are particularly useful when you need to break down complex queries into smaller, more manageable parts.

4. Conditional Aggregation:
   Conditional aggregation allows you to perform aggregations based on specific conditions. For example, you may want to calculate the average salary for each department, excluding salaries below a certain threshold. 

These advanced SQL techniques can significantly enhance your query performance, flexibility, and ability to handle complex data manipulations. However, it's essential to consider the specific database system you are using, as some techniques may vary slightly across different DBMSs.
🇬🇧 Trying to make sense of the job market UK 🇬🇧
Tags: help, discuss
Published: 2023-05-30 15:57:54

I really want to return to development as a Svelte or Vue developer - I find that React is fine but many many people all doing that, and personally I've come to appreciate simplicity that particularly on Svelte offers and so I have now got to think should I become a niche developer or follow everyone else.

My search around the state of JS survey and indeed.com show me that jobs exist

Also now iv'e been out of practice in the eyes of an interviewer for a little while how can I shake that!

I know this is all questions for chatGPT but I need your experience :D