APIs can have different architectures and standards, one of which is REST. REST stands for representational state transfer and is a commonly used architecture when implementing and creating APIs for the web. Choosing a web framework for a REST API implementation is not as trivial as one might think; there are many metrics to consider, one of which is performance. In this study, we compared the most used back-end web frameworks in 2021, ASP.NET Core, Express.js, and Flask, to see which performs best in throughput, response time, and computer resource usage. Finding the best-performing framework will help future developers choose which framework to use in terms of performance. Selecting a good framework from the beginning is essential to prevent the need to change framework in the future. To benchmark the different APIs, we did an experiment where we used JMeter, an open-source software for testing the performance of websites and APIs. By varying the number of virtual users and throughput, we were able to find the limit of each framework and their respective resource usage during different loads. We have concluded that ASP.NET Core had the best performance when it comes to response time and throughput. Furthermore, ASP.NET Core had the most efficient memory utilization throughout the entire experiment, and during loads higher than 4500 throughputs per second, it was also the most CPU efficient. Below 4500 throughput per second, Express.js was the most CPU-efficient framework but still had more memory usage than ASP.NET Core. According to our metrics, the performance of Flask was far behind Express.js and ASP.NET Core and should therefore not be considered a high-performance framework.

The Representational State Transfer (REST) architecture style surfaced quickly to be the favorable scheme to standardize the communication for network-based hypermedia systems due to its uniform discipline. As a result, various giant web services adopted the REST architecture as their primary architectural choice for their services. Regardless of the REST style's uniform discipline, de-facto practices appeared among REST services. Consequently, numerous studies have analyzed REST services and found to a significant extent, misalignments between the theoretical aspects of REST and the practices of REST. One of the studies examined a set of services that claimed to be REST against a class of 17 design criteria that realize the principles of the REST architecture, and it found that the majority of the subject services were inconsistent in applying the REST principles. This study has followed the research mentioned earlier and examined a limited set of REST services and surveyed REST practitioners to examine their practices against the same class of the 17 design criteria to determine to what extent they are applying the 17 design criteria and analyze the statistical differences between the practices of REST services and the practices of REST practitioners. The study results show that REST services and REST practitioners applied most of the 17 design criteria. However, the study also found heterogeneous practices in REST services that go against the principles of the REST style. Furthermore, the statistical analysis results suggest a misalignment between the practices of REST services and REST practitioners in relation to the 17 design criteria.

RESTful services are becoming increasingly popular. This work, that was carried out at Scania IT, investigates how a RESTful service should be designed and specified so that it meets the demands of an enterprise environment. In particular, this report will focus on documentation and validation of RESTful services, i.e. specifications. These are important aspects in an enterprise environment. The investigation consists of a comparative case study of four specification formats and Hypermedia As The Engine Of Application State (HATEOAS). The results show that the most commonly used specification formats have flaws. They also suggest that Swagger and RAML (RESTful API Modeling Language) are the two most mature formats. The results also show that HATEOAS, which is a more dynamic approach, can be useful in an enterprise environment but that it requires careful design. / REST-tjänster blir alltmer populära. Detta arbete, som utfördes på Scania IT, undersöker hur en REST-tjänst bör designas och specifieras för att möta de krav som finns i en enterprise-miljö. Specifikt kommer denna rapport att fokusera på dokumentation och validering av REST-tjänster, med andra ord specifikationer. Dessa är viktiga aspekter i en enterprise-miljö. Undersökningen består av en jämförande fallstudie med fyra specifikationsformat samt Hypermedia As The Engine Of Application State (HATEOAS). Resultaten visar att de mest vanligt förekommande specifikationsformaten har brister. De antyder också att Swagger och RAML (RESTful API Modeling Language) är de två mest mogna formaten. Resultaten visar också att HATEOAS, som är ett mer dynamiskt angreppssätt, kan vara användbart i en enterprise-miljö men att det kräver omsorgsfull design.

The goal of this project has been to create an online store for a music store called Music for All. The company's business concept is to sell new and used music equipment online with payment systems via mail or Paypal. The project consists of three separate parts: the first part that stores product information in a SQL Server database created via ASP.NET Core Web API and Entity Framework, the second part consists of an admin interface that contains a login system created by ASP.NET Core Identity Framework which make it possible for a logged in admin be able to create, delete and update products through a Headless CSM which was created by ASP.NET Core MVC and Entity Framework Core. The online store was developed via React.JS, Next.Js and Redux, which created functionality for consuming the REST API and functions that increased the web application's availability and usability. The REST API was developed via ASP.NET Core. The design was performed via React.JS and Sass and Node.JS to be able to execute JS code on the browser. / Målet med detta projektet har varit att skapa en webbutik för en musikaffär som heter Music for All och skulle etablera sig i sommaren. Företagets affärsidé var att sälja nya och begagnade musikutrustningar på nätet med betalningssystem via post eller Paypal. Projektet utvecklades i tre separata delar där en del lagrade produktinformationer i en SQL Server databas som skapades via ASP.NET Core Web API och Entity Framework, andra delen bestod av ett admingränssnitt som innefattade ett inloggningssystem som skapades av ASP.NET Core Identity Framework för att inloggade anställda skulle kunna använda ett innehållshanteringssystem/Headless CSM som skapades via ASP.NET Core MVC och Entity Framework Core. Webbutiken utvecklades via React.JS, Next.Js och Redux som skapade både funktionalitet för konsumering av REST API:et och funktioner som ökade webbapplikationens tillgänglighet och användbarhet. REST API:et utvecklades via ASP.NET Core. Designen utfördes via React.JS, Sass och Node.JS för att kunna exekvera JS kod på webbläsaren.

Application Programming Interfaces (APIs) are an important component in modern-day web applications. Representation State Transfer (REST) has been the de facto standard for building web APIs since its inception in 2000. In 2015 Facebook launched GraphQL, a technology with the purpose of solving some of the drawbacks of traditional REST APIs. However, few scientific studies have yet to assess the benefits and drawbacks of GraphQL vs REST from a performance standpoint. In this study, a controlled experiment was conducted to assess three categories of runtime performance: response time, CPU consumption and memory consumption. Results show that GraphQL consumes more server-side resources than REST, except in certain scenarios, while response time depends highly on the query. When fetching the same amount of data, REST is more efficient than GraphQL in every regard.  Keywords: Web Development, Application Programming Interfaces, REST, GraphQL, Performance.

Projektet hade som syfte att hjälpa personer med diagnosen dyspraxi, mer specifikt oral dyspraxi. Oral dyspraxi yttrar sig som problematik medatt koordinera munrörelser vilket kan leda till svårigheter att prata tydligt och därmed även saker som svårigheter att kommunicera med andra och talgenans. Dyspraxi yttrar sig som tydligast hos unga barn då dessa ännu inte hunnit utveckla metoder för att dölja sin funktionsnedsättning. I projektet uppstod idén att denna problematik kunde hjälpas genom att skapa motivation och glädje i talpedagogiksessioner som annars kan kännas som utdragna för det barn som genomgår dem. Denna tanke ledde till efterforskning kring gamification och resulterade i ett brädspel som används av barnet med dyspraxi ihop med en talpedagog baserat på talpedagogikmetoden Rapid Syllable Transition Treatment. Brädspelet ficknamnet svammel utifrån de nonsensord som förekommer inom RapidSyllable Transition Treatment.

The report presents information about the development of an intern logbook made for the company Ångtvättbilen Västernorrland. The application is created with the goal and purpose to make the daily data management more effective and to gather all the coworkers information in one tool. The application is build up with the help of WordPress where the developer creates an own theme together with new post types, plugins and CRUD-functionalities. The project results in an working, responsive, progressive web application where the members can log in to their own personal account. In the app, the coworkers can save data from the work that they are doing or have done. When a member enters information about a work and saves it, the data gets available for all the coworkers to see in an table. The information is from there possible to both edit and delete. The webbapplication also includes a page for image upload where the members can submit images together with an text to the social media manager. The images is delivered by an automatic email. On the webpage there is also a page for a shoppinglist where all the members can add articles that need to be bought. The shoppinglist has all the CRUD-functionalities too. At last every coworker has their own member-profile where they can manage their own information and where they can upload an image of themself. All the personal-information is also visible to the other members on the site. The tools in the application is available from front-end and the coworkers does not have access to the WordPress administration. The goal and purpose of the project is achieved. / Examensrapporten innefattar utvecklingen av en intern företagsapplikation, i form av en loggbok som skapas till Ångtvättbilen Västernorrland. Applikationen skapas med syftet och målet att effektivisera företagets datahantering samt för att ge medarbetarna möjlighet att samla allas information på ett ställe. Applikationen, som blir en progressive web app byggs upp i WordPress genom att utvecklaren skapar ett eget tema samt egna post-typer, plugins och CRUD-funktionaliteter. Arbetet resulterar i en fungerande, responsiv webbapplikation med möjlighet för medarbetarna att, med ett eget konto logga in i applikationen för att därefter ha möjligheten att bland annat lagra data från arbeten som utförs och utförts. När en medarbetare lagrat information om ett arbete visas denna information, tillsammans med författarens namn upp i en tabell synlig för alla medlemmar. Informationen går därefter både att redigera och radera. Webbplatsen innehåller även en undersida för bilduppladdning där medarbetarna kan skicka in bilder tillsammans med bildtext till ansvarig för sociala medier som då får tillgång till datan genom att ett automatiskt mail skickas ut. På webbplatsen finns även en sida som innehåller en inköpslista där alla medarbetare kan fylla på med vad som ska beställas eller köpas in. Inköpslistan har också CRUD-möjligheter så att all data som skapas kan läsas ut, redigeras och raderas. Tillsist har även varje medarbetare en egen profil där de egna uppgifterna kan redigeras samt att alla medlemmar visas upp i en lista tillsammans med dess uppgifter. Alla verktyg på webbplatsen är tillgängliga från front-end och medarbetarna har inte tillgång till baksidan, det vill säga WordPress-gränssnittet.

This diploma thesis deals with the creation of a solution for continuous data acquisition from web sources. The application is in charge of automatically navigating web pages, extracting data using dedicated selectors, and subsequently standardizing them for further processing for data mining.

This diploma thesis deals with desing and implementation of order management system in restaurant facilities. The main goal was to create a cross-platform mobile application that allows users to order items through web REST API. System will then distribute these orders to facility staff. The system verifies authenticity of orders by using unique dynamic QR codes.

Smart devices (or things) in the realm of IoT (Internet of Things) talk to each other and transfer data over the Internet.IoT vendors provide APIs for their clients to send data to the gateways and application servers. However, there is a lack of guidelines on how a vendor would design its API and resource URIs (Uniform Resource Identifiers). A generic design solution –design patterns– would make the API design and development easier for the vendors. Design patterns are reusable solutions to recurring problems and provide improved reusability and understandability. Currently, there are no design patterns for URIs of IoT APIs that IoT vendors can use. In this paper, we analyzed more than 1,300 URIs from 13 IoT APIs including IBM Watson and Microsoft Azure, and proposed eight novel design patterns for URIs of IoT APIs. We analyzed one dataset divided into two subsets: (1) analysis set with 70% of all our URIs to define design patterns for URIs of IoT APIs and (2) validation set with the remaining 30% of the URIs to verify the prevalence of the defined design patterns. We could map 84% of our validation set to the defined design patterns, i.e., design patterns are prevalent in the IoT domain.