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This week on my CS Journey, I want to look closely at the topic of REST API Design. I know We have been doing several activities regarding the topic in class and the homework assignment is associated with it, however, I wanted to be very knowledgeable on the topic, so I decided to do more research. REST is an acronym for Representational State Transfer. A REST API is a way for two computer systems to communicate over HTTP in a similar way to web browsers and servers do. Let start by looking at what An API is,  An API is an application programming interface. It is a set of rules that allow programs to talk to each other. The developer generally creates the API on the server and allows the client to talk to it and the REST determines how an API should look like.

Now let’s look at the anatomy of a request is, An API request has four main important parts: The endpoint, The method, The headers, and The data or body. When an API interacts with another system, the touchpoints of that communication are considered endpoints. Each endpoint is the location from which APIs can access the resources they need to carry out to do their function. The way APIs work is using  “requests” and “responses.” Meaning that each URL is called a request while the data sent back to you is called a response.

Generally, when it comes to methods it has five types. Which are: GET, POST, PUT, PATCH, and DELETE. These methods provide meaning for the request you’re making. They are also used to perform four possible actions that are Create, Read, Update, and Delete also known as CRUD. Next, the Headers are used to provide information to both the client and the server. It can be used for many purposes, such as authentication and providing information about body content. Lastly, the body or the data is what contains information you want to be sent to the server. This option is only used with POST, PUT, PATCH, or DELETE requests.

Overall, I learned a lot from this blog. The source I used explained the topic very well. I highly recommend everyone to check it out, because it has a variety of examples and documents that you need to know about REST APIs to be able to read the API documentation and use them effectively. It also goes deep into the methods and the request meaning of each of them, I think it is very important to understand those concepts because companies all over the world are using APIs to transfer vital information, processes, transactions, and more.




From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.

What is Rest API


API is short for Application Programming Interface (API), which describes a class library’s characteristics or how to use it. Your personal library may contain “API documentation” of available functionality.

A REST API in API Gateway is a collection of resources and methods integrated with back-end HTTP endpoints, Lambda functions, or other AWS services. You can use API Gateway features to help you with all aspects of the API lifecycle, from creation through monitoring your production APIs.

API Gateway REST APIs use a request/response model where a client sends a request to a service and responds back synchronously. This kind of model is suitable for many different kinds of applications that depend on synchronous communication.

When many people refer to API documentation these days, they often refer to an HTTP API that might share your application data over the web. For example, Twitter provides an API that allows users to request tweets in a specific format to easily import them into their own applications. This is where the HTTP API is potent. It can mix and match data from multiple applications to a mixed application or create an application that enhances the experience of using other people’s applications.

It is an application that allows us to view, create, edit, and delete parts.

REST is the shorthand for Representational State Transfer, which was proposed by Roy Fielding T to describe the standard way of creating an HTTP API, and he found that the four common behaviors (view, create, edit, and delete) could all be mapped directly to the implementations in HTTP.

The different HTTP methods:









Most of the time, when you’re looking at your browser’s dots, you’re using the HTTP GET method. The GET method is only used when you request resources from the Internet. When you submit a form, you often use the POST method to send data back to the site. As for the other approaches, some browsers may not fully implement them at all. But that’s fine if it’s for our use. We have many HTTP methods to choose from to help describe these four behaviors, and we will use client libraries that already know how to use these different HTTP methods.

Rest API benefits:

Resource oriented, easy to see

To GET something, you need to GET (GET is safe, does not modify the service resource), you need to POST (POST is unsafe), you need to PUT (PUT is idempotent), and DELETE (DELETE is idempotent).

Traditional CRUD requires four different interfaces, but the REST API requires only one. (Distinguish between different requests)


From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

What’s the difference between JavaScript and Java?

 What is Javascript?

It’s a scripting language that runs in a browser, and Javascript can do almost anything on a Web page:

HTML can be manipulated, providing a tool to change HTML at runtime. Events can be attached and executed, in line with the idea of event-oriented programming. The data verification function verifies the validity of the form of data when submitting the form. The operation of the client’s browser: forward, backward, refresh, jump, open a new window, print, etc. Cookies can be created and used.

What is Java?

Java is a programming language introduced by Sun. It is an interpreted language with syntax rules similar to C++. Java is also a cross-platform programming language. The program written in Java language is called “Applet” (small application program). After compiling it into class files by the compiler, it is stored in the WWW page and marked on the HTML file accordingly. As long as the client software of Java is installed, the client can run the “Applet” directly on the network. Java is well suited to enterprise networks and Internet environments and is now one of the most popular and influential programming languages on the Internet. Java has many remarkable advantages, such as simplicity, object-oriented, distributed, interpretability, reliability, security, structural neutrality, portability, high performance, multithreading, and dynamism. Java dispenses with C++ features that do more harm than good and many that are rarely used. Java can run on any microprocessor, and programs developed in Java can be transmitted over the network and run on any client.

Different data types

Java has eight data types: byte, short, int, long, float, double, char, and Boolean, while JavaScript has three data types: number, String, and Boolean.

In addition, there are differences in Java and Javascript variables.

They are positioned differently

Unlike Java, which is a completely object-oriented programming language that requires you to design objects before you can write in Java, JavaScript is an object-oriented scripting language that provides developers with built-in objects, making it easier and less time-consuming.

Link in different ways

Unlike Java, which USES static linking, where object references must be made at compile time and the compiler needs to implement strong type checking, JavaScript USES dynamic linking, where object references can be checked at run time.

Different USES

The most essential difference between them is their usage. At present, Java is widely used in PC terminal, mobile terminal, Internet, data center, and so on, while JavaScript is mainly used to embed text into HTML pages, read and write HTML elements, control cookies, and so on.

Java and JavaScript have different strengths and different specialties. The Java arena is programming, while JavaScript’s heart is in Web pages, where it can do almost anything.


From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

How does Docker Assist Big Data analyst

 As we dive deeper into the semester we start to learn more tools that will assistance us with open source networks. For this pertrucalr week I looked into how docker will assistance someone in a bigdata constintration like myself. While doing my research I found out that docker allows us to put data or large files into containers. Which will allow us to deliver and respond much quicker to the customer with the use of docker. This is enabled not only the customer but the data scientist to have a more organized platform for information to be transferred. This is valuable because instead of  having to go through multiple platforms to transfer information instead with the use of docker you are able to use one platform to put the infromation into a container which will then transfer it to the client. With the power of docker it allows big data scientist to be self-sufficient and build effectce models which can be tested and modified on multiple occasions with out having to change the main structure of the data. With the use of docker it allows us to have the developer systems and product environment to be constant and be monitored under the same platforms, while prior to docker we where unable to do such a thing because the environments would always switch up and not be uniform. Finaly more systems should incorporate docker into there platforms because it allows us to package the information as applications, dependencies to be deployed as one single package. 

From the blog Nicholas Dudo by and used with permission of the author. All other rights reserved by the author.


This week on my CS Journey, I want to look more into JavaScript and how it is used in docker. Although we did a few activities on JavaScript, I was still confused so I decided to read and research more into it. JavaScript is a text-based programming language used both on the client-side and server-side which is mainly for the web. Many of the websites use JavaScript on all browsers making JavaScript the most-deployed programming language in history. The name JavaScript is quote misleading due to the resemblance of java programming language however, JavaScript is completely different from the Java programming language. Both Java and JavaScript are written, assembled and executed differently, and each has dramatic differences when it comes to what it can do. JavaScript is mainly used for: Adding interactive behavior to web pages like Change the color of a button when the mouse hovers over it, displaying animations, creating web and mobile apps, Game development, and  building web servers.

Now let’s get into Node.js which is what is used in docker. Over the decade Node.js has enabled JavaScript programming outside of web browsers, which has a dramatic success of Node means that JavaScript is now also the most-used programming language among software developers. Node.js is an open-source, cross-platform runtime environment for developing server-side and networking applications. Node.js applications are written in JavaScript and can be run within the Node.js runtime or any other operating systems. some of the features I learned from the blog is that, Node.js  can be  Asynchronous and Event-Driven meaning that All APIs of the Node.js library are asynchronous, it essentially means a Node.js based server never waits for an API to return data. It can be very fast since it is being built on the Google Chrome’s V8 JavaScript Engine, Node.js library is very fast in code execution, and lastly, No Buffering- Node.js applications never buffer any data. These applications simply output the data in chunks. 

The diagram below also helped to understand the concept well.

I highly recommend that everyone read the assigned book on JavaScript because it is very helpful in terms of understanding the concepts and the book covers a wide variety of interesting topics. Also, I suggest that everyone follow this tutorial it is an example that shows how to get a Node.js application into a Docker container. The guide also helps to understand basics of how a Node.js application is structured.

Here is the tutorial:

Sources :

From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.

What is UML and the differences with OOM

The difference between OOM and UML by definitions.

Object-oriented modeling (OOM) is the construction of objects using a collection of objects that contain stored values of the instance variables found within an object. Unlike models that are record-oriented, object-oriented values are solely objects.

UML stands for “Unified Modeling Language. The purpose of UML is visually representing a system along with its main actors, roles, actions, artifacts or classes, in order to better understand, alter, maintain, or document information about the system. We can say that UML is the new approach for documenting and modeling the software

Object-oriented modeling is the process of construction of objects. Objects contain stored values of the instance variables. It creates the union of the application and database development. The union is then transformed into a unified data model. This approach makes object identification and communication easy. It supports data abstraction, inheritances, and encapsulation. Modeling techniques are implemented using OOP supporting languages. OOM consists of the following three cases: Analysis, Design, and Implementation

UML, short for Unified Modeling Language, is a standardized modeling language consisting of a set of diagrams. UML is used to help system developers clarify, demonstrate, build, and document the output of a software system. UML represents a set of practices that have proven successful in modeling large and complex systems and is a very important part of the development of object-oriented software and software development processes. UML primarily USES graphical notations to represent the design of software projects. Using UML helps project teams communicate, explore potential designs, and validate the architectural design of the software. Below we will walk you through what UML is, the history of UML, and a description of each UML diagram type, supplemented by UML examples.

Why we like UML? What is the benefit of UML?

As the value of software products increases, companies are looking for technologies to improve software production processes, improve quality, reduce costs, and shorten time to market. These technologies include component technologies, visual programming, and the application of patterns and frameworks. Companies are also looking for technology that can manage the complexity of systems as they grow in scope and scale. They also recognize the need to address periodic architectural issues such as physical distribution, concurrency, replication, security, load balancing, and fault tolerance.

In the end, UML provides users with an off-the-shelf, expressive visual modeling language so that they can develop and exchange meaningful models. It provides Extensibility and Specialization mechanisms for core concepts. It Independents of the specific programming language and development process. Provides a formal basis for understanding the modeling language. It encourages the development of the market for object-oriented tools. It supports higher-level development concepts such as collaboration, frameworks, patterns, and components. It integrates Best Practices.


From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

Why use Docker?

 This week on my CS Journey, I want to talk about Docker. I know we went over several different activities in class; however, I was still a little confused, so I decided to look more into detail from outside sources to understand the concept and terms well. Docker is a tool designed to make it easier to create, deploy, and run applications by using containers. A container is not so much different than a Virtual Machine But, instead of creating a full operating system, a Docker Container has just the minimum set of operating system software needed for the application to run and rely on the host Linux Kernel itself.

The first blog talked about the importance of docker and how to step a docker file in the root directory. There was a 12-minute video from YouTube that explained the concept very well. I learned a lot from that YouTube video. The blog also talked about creating a docker-compose file which is a tool that allows you to deploy and manage multiple containers at the same time. I learned the concepts that go inside a file including, From where to take a Docker file to build a particular image, Which ports you want to expose, How to link containers, Which ports you want to bind to the host machine, and other key commands. This blog was very helpful to do assignment 4 building the Nginx and the MongoDB servers.  

The next blog talked about the benefit of docker, one of the major benefits of containers is portability. Containers can run on top of virtual machines, or in the cloud. This has made it easier to use cases of containers to be around software development. People now can write applications, place it in a container, and then the application can be moved across various environments, as it is encapsulated inside the container which I think is helpful in the environment. It was quite interesting to learn that Docker offers privately hosted repositories of containers, which are about $1 per container. Many tech companies are looking to get into the action of using docker at their place especially the cloud hosting companies.

It was interesting to learn about the concepts of Docker, how to use the commands properly and how major companies are using docker at their workplace, Overall, the blogs and the video helped me to understand the tools behind docker especially running your image from localhost to port and other interesting concepts. I highly recommend everyone check out the video it is well explained.




From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.

Docker Review


Today I want to explain some information from what I learned in the class and some sources outside.
What is Docker?
Docker is a package of Linux containers, providing a simple and easy to use container interface. It is by far the most popular Linux container solution. It is a kind of visual machine but it also has differences from the visual machine.
Docker packages the application and its dependencies in a single file. Running this file generates a virtual container. The program runs in this virtual container as if it were running on a real physical machine. With Docker, you don’t have to worry about the environment.
Generally speaking, Docker’s interface is quite simple. Users can easily create and use containers and put their own applications into the containers. Containers can also be versioned, copied, Shared, and modified just like normal code.
The main USES of Docker currently fall into three categories. First, provide a disposable environment. Examples include testing other people’s software locally and providing a unit test and build an environment for continuous integration. Second, provide flexible cloud services. Because Docker containers can be opened and closed on demand, they are ideal for dynamic dilatation and shrinkage. Third, establish micro-service architecture. With multiple containers, a machine can run multiple services, so the microservice architecture can be simulated on its own.
Docker mainly contains three basic concepts, namely image, container, and warehouse. Once you understand these three concepts, you can understand the entire life cycle of Docker. The following is a brief summary of these three points that we have a short view of the class.
Docker image is a special file system that not only provides the programs, libraries, resources, configuration files required by the container runtime but also contains some configuration parameters for the runtime. 
The essence of containers is processed, but unlike processes that execute directly on the host, container processes that run in their own separate namespace containers can be. Create, start, stop, delete, pause, and so on, the relationship between an image and a container is analogous to classes and instances in object-oriented programming.
Once the image is built, it is easy to run on the current host, but if you need to use the image on other servers, you need a centralized service to store and distribute the image, and Docker Registry is one such service. A Docker Registry can contain multiple repositories; Each warehouse can contain multiple tags; Each label corresponds to an image, where the label can be understood as the version number of the image.
On the whole, Docker is a concept that is more and more interesting, which is worth our in-depth understanding. 

From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

Adapter Design Pattern


    This week On my Blog, I want to talk about a design pattern. The One I want to focus on is Adapter Design Pattern. Adapter design pattern Convert an interface of a class into another interface clients expect. The adapter lets classes work together that couldn’t otherwise because of incompatible interfaces. The adapter design pattern is a structural design pattern that allows two unrelated/uncommon interfaces to work together. In other words, the adapter pattern makes two incompatible interfaces compatible without changing their existing code. Now Let’s take a look at an example that shows how the design works. From the blog, I used it provided a diagram that I think is helpful to understand the design pattern. In this diagram, Socket wrenches provide an example of the Adapter. A socket attaches to a ratchet, provided that the size of the drive is the same. Here a Ratchet is ½ in size and the socket is ¼ without using an adapter you cannot connect the ratchet and socket together. 

    Now let us take a look at the benefits and liabilities of using the adapter design pattern. The first benefit is that you can let any two unrelated classes run together. Second, Improved the reuse of classes, it Increased the transparency of classes and it has Good flexibility. Now for the Liabilities, the Adapter design pattern takes Too much use of adapters will make the system very messy and difficult to master as a whole. For example, if an interface A and B are implemented and interface B is adapted internally. If too many tasks are running in A system, it will be A disaster. So, if it’s not necessary, you can simply refactor the system without using an adapter. Also, in object-oriented programming especially in JAVA it inherits at most one class, it can only adapt to one adapter class at most, and the target class must be an abstract class.

    A real-life example that I found was about the card reader ACTS as an adapter between the memory card and the laptop. You insert the memory card into the card reader and insert the card reader into the portable computer. The memory card can be read from the portable computer.

    This source is helpful to understand the design pattern even more. I would suggest you take a look at the website because it goes into further detail about the Adapter design pattern, including various examples using diagrams and JAVA codes. 



From the blog haorusong by and used with permission of the author. All other rights reserved by the author.

Facade Design Pattern

This week on my CS Journey, I want to talk about the design patterns, Especially the Facade design pattern. In class, we also learned about other designs which are helpful. However, I wanted to focus on the Facade design pattern. To start of Facade is a structural design pattern that adds an interface to an existing system to hide its complexities. In other words, it provides a simple interface that can be used to manipulate more complex logic behind the scenes, that are hidden from the main user. According to the Gang of Four, the Facade pattern intends to “Provide a unified interface to a set of interfaces in a subsystem” From the blog I used it provided a diagram that I think is helpful to understand the design pattern. In the diagram, we can see that Facade is acting as an interface for the complex Subsystems that are hidden from the main clients. 

Now let’s take a look at a real-life example. A good example that I found was When a computer starts up, it involves the work of CPU, memory, hard drive, and other subsystems. To make it easy to use for users we can add a Facade that wraps the complexity of the task and provide one simple interface instead. This applies to the Facade design pattern because it hides the complexities of the system and provides an easy interface to the users. 


One of the liabilities is that a Facade might provide limited functionality in comparison to working with the subsystem directly. Does not prevent applications from using subsystems classes if they need to. Also, it can increase the number of wrapper classes. Another liability is that Facade can perform way too many tasks. One of the benefits is that it reduces compilation dependencies is vital in large software systems. Overall, The Facade design pattern is helpful when dealing with the complex system because It enables us to use the complex system much more easily.


There are a lot of examples, diagrams, and Java Codes, readings and a link to a GitHub resource that are provided in the blog I used. I would suggest you to take a look at the website because it goes into further detail about the facade design pattern, including various examples using diagrams and also this reference contains a lot of information that is broken down into easy steps which are user friendly.


Source :

From the blog Derin's CS Journey by and used with permission of the author. All other rights reserved by the author.