Skip to main content

Set up a web server for learning HTTP headers


Motivation


We all follow the client-server model using the HTTP protocol for most of our web apps today. In development, we simply may have a backend API server and a frontend (web pages or mobile apps) only. However, it seemed that a proxy server is always required for production. In fact, most of the hardest issues in production come from integration. The requests and responses might be modified by the proxy server. Therefore, the understanding of HTTP protocol is one of the key skills to resolve those issues.

I wanted to dive deep into HTTP with some core concepts such as caching, cookies, and CORS. I didn't intend to go quickly rather than moved slowly to have a well understanding of what I do.

Prepare a server

The easiest way is to use my laptop as a server then I can just use "localhost". I can also use ngrok to make my web server online. Finally, I use an online tool such as RedBot to check the HTTP headers.

To make it more excited though, I deployed the app on AWS EC2. It was quite easy to launch an EC2 instance by using the wizard setup of AWS. Just simply use default settings for most of the cases. I was just curious about how to creating a new VPC (Virtual Private Cloud). To understand what exactly the IPv4 address and CIDR are, I first started to grab some knowledge about those topics by watching the following videos on YouTube


Next, I tried to create and do configure a virtual private network using Cisco Packet Tracer. I needed to configure IP address for involved devices: routers, servers, and laptop. Also, I did configure the routing tables for each router so that I could send packets among devices.

Coding

I used Express for my web server simply serving static files. I configured the HTTP header easily through passing the options of "express.static" middleware.

Deployment

Docker is my favourite tool for deployment. I created an image for my container running on my EC2 instance which I have already installed Docker. I also applied some best practices of Node.js and Docker. I built and pushed my Docker image into Docker Hub so that I could pull the image within the EC2 instance.

Happy coding!

Comments

Popular posts from this blog

Junit - Test fails on French or German string assertion

In my previous post about building a regex to check a text without special characters but allow German and French . I met a problem that the unit test works fine on my machine using Eclipse, but it was fail when running on Jenkins' build job. Here is my test: @Test public void shouldAllowFrenchAndGermanCharacters(){ String source = "ÄäÖöÜüß áÁàÀâÂéÉèÈêÊîÎçÇ"; assertFalse(SpecialCharactersUtils.isExistSpecialCharater(source)); } Production code: public static boolean isExistNotAllowedCharacters(String source){ Pattern regex = Pattern.compile("^[a-zA-Z_0-9_ÄäÖöÜüß áÁàÀâÂéÉèÈêÊîÎçÇ]*$"); Matcher matcher = regex.matcher(source); return !matcher.matches(); } The result likes the following: Failed tests: SpecialCharactersUtilsTest.shouldAllowFrenchAndGermanCharacters:32 null A guy from stackoverflow.com says: "This is probably due to the default encoding used for your Java source files. The ö in the string literal in the J...

Java 8 - Persistent data structure

The following is a series of posts about "functional programming in Java" which is the result of my understanding by reading the book " Java 8 in Action: Lambdas, Streams, and Functional-style Programming, by Alan Mycroft and Mario Fusco ". 1. Why functional programming? 2. Functional programming in Java 8 3. Java 8 - Using Functions as Values 4. Java 8 - Persistent data structure Persistent data structure is also known as a simple technique but it's very important. Its other names are functional data structure and immutable data structure. Why is it "persistent"? Their values persist and are isolated from changes happening elsewhere. That's it! This technique is described as below: If you need a data structure to represent the result of a computation, you should make a new one and not mutable an existing data structure. Destructive updates version public static A doSomething(A a){ a.setProp1("new value"); return...

Fulfilling Your Contribution Needs

Human resource management motivation Managing human today is quite different from the industrial age which treats people as just "chickens". Rather than people now are very important to the success of an organization. People are an organization's special resource. They should be encouraged to grow to contribute their effort and creativeness to their beloved working environment because the contribution is one of their most needs in life. Training people: getting rid of the ineffective model and adopting the new one The ineffective model of training people: Hiring new people --> giving them a crash course once --> expecting them working effectively.  That somehow makes sense but you're about to expect a luck because you do not really spend your effort for mentoring them. If they can work effectively, well...lucky you! Otherwise, you will blame that these people are ineffective and you let them go and hire the new ones. What a waste of time! The new effe...

DevOps Toolchain Enhancement

 Historically, our company ubitec had started with a customer project. Agile/Scrum was our proposal for working with customers. Time by time, Agile/Scrum also became our culture for software development. To be successful with this development approach, we somehow needed to have a fast release for customers (i.e. every one week). Back then, we had a build tool Jenkins which was responsible for having sprint release packages for our customers. The build job pipelines contain some steps such as gathering the artifacts, checking the code convention, running the tests, building docker images, and packaging an archived file (a zip file). The set of tools involved in a pipeline is roughly called a toolchain. It is just a part of a bigger process called the DevOps toolchain. Source: https://www.ibm.com/blogs/cloud-archive/2016/11/devops-architecture-available-on-bluemix-garage-method-site/ DevOps is a proven method that fits Agile. Today,  it is even treated as a mandatory factor...

Merging source in SVN

My team has used Primefaces for our projects. We sometimes have several branches of the projects with a new Primefaces's release. For example, we currently have a project with two branches, a branch for using Primeface 4.0, a trunk for using Primeface 5.0, and we are working these parallel branches. Our project looks like the following: - myProject - branches + primefaces4 + tag + trunk (primefaces5) My problem is how to copy the same source from the trunk to the branch "primefaces4". That is where SVN Merging can help! Here is the steps those I have conducted in my project. Step 1 : open the project with the branch "primefaces4" Step 2 : Team > Merge... Chose the trunk's URL. For example: http://192.168.9.10/svn/myProject/trunk Step 3 : Select the revision from "trunk" to merge. For example: +--revision--+--date--------+--author----+--comment---+ +  10        + 03.10.2014 + vanhuong   + f1: part 3 + +  9     ...