BookingApp

Table of Contents

• Introduction
• Before you Start
  • Is your Machine Compatible?
  • Programs to Install
  • Running on Virtual Machine
• Clone the BookingApp Project
  • Import to Eclipse
• Build the BookingApp Project
  • Build from Command Line
  • Build from Eclipse
• Run the BookingApp Application
  • Run through Jar
  • Run through Docker
• Setup X Server Environment for Docker
  • Linux
  • Windows

Introduction

BookingApp is a simple desktop application written in Java 17 for managing reservations developed with TDD, build automation and continuous integration practices. Once the application is launched, you can add your clients and their reservations via a Java Swing GUI. Informations are stored in a database server running as a Docker container. BookingApp is compatible with both MongoDB and PostgreSQL DBMSs, respectively via the Java Driver and Hibernate APIs.

💡 Tip: BookingApp followed by "project" indicates the entire job, which includes builds, tests and hence the source code, while "application" indicates the executable which you can launch and use.

On GitHub Actions are stored results about Maven builds and tests for Linux OS, MacOS, and Windows, and also the website status for the BookingApp project and the release status for the BookingApp application:

📝 Note: On Windows systems some unit and integration tests cannot be executed due to lack of compatibility of required Docker images, like MongoDB and PostgresSQL. If you are brave enough, you can fill the void by creating custom Docker images for MongoDB and PostgreSQL starting from a Windows OS base layer.

On Coveralls are published the history and statistics of BookingApp test code coverage, while on SonarCloud are published analysis of BookingApp code quality, particularly on reliability, security and maintainability:

Before you start

Is your Machine Compatible?

If you just launch the BookingApp application with PostgreSQL as DBMS there are no known machine requirements.

Otherwise, the BookingApp project runs a Docker container with MongoDB, the version of which is greater than 5.0 and requires the use of Advanced Vector Extensions (AVX) instructions. To determine whether your CPU model supports AVX, check the manufacturer’s website and enter your CPU model number. Alternatively, below there are other methods specific to the Operating System (OS).

📝 Note: Even if your machine supports AVX instructions, a hosted Virtual Machine may disable them due to virtualization issues. See the section on Running on Virtual Machine for fixing this possible problem.

Linux and MacOS

To check if CPU has AVX capabilities on Unix systems, run the following command on the terminal:

grep avx /proc/cpuinfo

If the output is not empty then your cores have AVX support.

Windows

On Windows systems, enable AVX capabilities directly by running the following command on a Command Prompt as Administrator:

bcdedit /set xsavedisable 0

If you see a confirmation message then your cores have AVX support.

Programs to Install

To run the BookingApp application, at least the following programs must be installed on your computer:

• Java 17
• Docker Engine

To replicate builds, tests and so on, the BookingApp project also requires:

• Git
• Docker Compose

You can also build the BookingApp project with Maven from the command line. In this case Maven is mandatory, possibly with the version 3.8.6.

If you want to use an IDE, the BookingApp project was developed using Eclipse, so it is recommended.

Running on Virtual Machine

It is possible to clone and run BookingApp on a OS installed on a Virtual Machine (VM) program (e.g. VirtualBox, VMware Workstations, etc.), but it may not work due to lack of support for AVX/AVX2 instructions, even if your host machine's CPU supports them.

Hosted by Windows 11

On Windows 11 the supporting of AVX/AVX2 instructions in a VM may fail due to virtualization problems. In this case it's necessary to:

• disable the hypervisor launch which is enabled by default.

  First of all, check if the hypervisor is executing: press together WIN + R > enter msinfo32 > in the System Summary window you should find the following entry (otherwise skip over to the next point): A hypervisor was detected. The features required for Hyper-V will not be displayed. In this case, open a Command Prompt as Administrator and run bcdedit /set hypervisorlaunchtype off. Then restart your machine for applying changes.
  

  When you need to undo the changes, open a Command Prompt as Administrator and run bcdedit /set hypervisorlaunchtype auto. Then restart your machine for applying changes.

• disable Windows security Memory Integrity.

  ⚠️ Warning: This is a very bad thing to do because the Memory integrity feature is stated to prevent injection attacks into virtualization-based security processes. Unfortunately, this is require in order to enable AVX/AVX2 instructions in VMs.

  You can find it on Settings > Privacy & security > Windows Security > Device security > Core isolation details > Memory integrity. As soon as turned this feature off, restart your machine to allow Windows to apply the change.

If everything went right, your VM should now support AVX/AVX2 instructions as well as the host machine. You can make this check running the previous section instructions on the OS installed on your VM. If you're using VirtualBox you can make this check earlier by looking at the below right side of your running VM: there must be an icon like . Instead, if you see an icon like , it means that hypervisor is still running (and the virtualization is slower, just like a turtle) then AVX/AVX2 core instructions will be not supported.

⚠️ Warning: It is really recommended to revert all the changes here described as soon as you no longer use the VM.

Clone the BookingApp Project

Use the Git command line to clone the BookingApp project. Choose any folder and run on the terminal:

git clone https://github.com/marcopaglio/BookingApp.git

A copy of the BookingApp project will be downloaded.

💡 Tip: In the chosen folder will appear a directory named BookingApp/. This is the project root directory.

Import to Eclipse

📝 Note: Following steps have been defined using EclipseIDE 2022-12 and 2023-09. Different versions may involve slightly different steps.

Once cloned via Git command line, you can import the BookingApp project to Eclipse:

1. Open Eclipse and choose any workspace location.
2. From the top left bar: File > Open Projects from File System... > use Directory.. to choose for the project root directory > make sure of selecting the Search for nested projects option > from the Folder list import all subfolders but not the root folder BookingApp > Finish.

📝 Note: Just imported on Eclipse, there may be appeared some dependencies errors on the Problems tab. Don't worry, just File > Refresh once and they will go away. See the Eclipse Configuration Guide for other solutions for possible problems.

Build the BookingApp Project

When you build the BookingApp project is necessary to have DBMSs' Docker image locally, otherwise they will be downloaded during the build execution causing a possible timeout failure. In order to avoid this, before the very first build, run the following commands on the terminal:

docker pull mongo:6.0.7
docker pull postgres:15.3

📝 Note: On Linux and MacOS you have to precede Docker commands with sudo. You may not use it if you add your user to the Docker group. See the Docker Installation Guide for more details.

Build from Command Line

You can build the BookingApp project from the command line with Maven or Maven Wrapper. In next build commands replace the placeholder <MVN> with the right script command, depending on what you choose:

• with Maven use mvn.
• with Maven Wrapper use ./mvnw for Unix systems (e.g: Linux, MacOS, etc.), or ./mvnw.cmd for Windows.

💡 Tip: Maven Wrapper is very useful for users that don’t want to install Maven at all. For this reason building with Maven Wrapper is recommended. If you prefer using Maven directly, make sure to install Maven yourself, and preferably with the same version used for the BookingApp project, that is 3.8.6, otherwise build might fails.

Build Commands

Place yourself into the project root directory and open a Command Prompt. The very basic command to build the BookingApp project is as follows:

<MVN> -f booking-aggregator/pom.xml clean install

Its execution will remove unnecessary files generated in previous builds and install dependencies locally for each module. In this way, you can then build each sub-module indipendently, just change booking-aggregator with one between booking-domain-module, booking-business-module and booking-ui-module in the previous command.
Additionally, all unit, integration and end-to-end tests will be performed with Maven. If the command is executed for a sub-module, tests will be executed only for the specific module.

Alternative builds can be run by adding one or more profiles at the end of the previous command:

• -Pjacoco adds test coverage. BookingApp project already provides test coverage results on Coveralls, but you can see them yourself once the execution finishes at /booking-report/target/site/jacoco-aggregate/index.html.

• -Ppitest adds mutation testing. BookingApp project already provides mutation testing results on the website, but you can see them yourself once the execution finishes at /booking-report/target/pit-reports/index.html.

• -Pskip-gui-tests skips tests that require a graphical environment. This profile is useful to quickly see how builds work, since GUI tests slow them down.

• -Pdocker dockerizes the application. The Docker image created is named booking-app and it is verified with both MongoDB and PostgreSQL.

  📝 Note: This Maven profile opens the BookingApp application inside a Docker container, therefore it needs the access to the X display server in order to work propertly. Please, make sure you setup X server environment for Docker before using the -Pdocker profile.

Build from Eclipse

You can also build the BookingApp project using launch files from Eclipse. They are located into booking-aggregate, booking-domain-module, booking-business-module and booking-ui-module inside launches folders. Just right click on the .launch file > select Run As > click on the same name Maven configuration to start the build.

Launch file naming convention consists of a radix that is the module name, and a suffix that indicates what the build does in particular:

Suffix	What it does
-install	Runs all tests and installs dependencies locally for each module.
-verify	Runs all tests.
-test-without-docker	Only runs unit tests that don't require the use of Docker.
-junit-report	Runs all tests and generates unit test results at /target/site/surefire-report.html and integration and end-to-end test results at /target/site/failsafe-report.html.
-jacoco	Does the same thing as -Pjacoco of Build commands section. If launched on a sub-module, test coverage results can be found at /target/site/jacoco/index.html.
-pitest	Does the same thing as -Ppitest of Build commands section. If launched in a sub-module, mutation testing results can be found at /target/pit-reports/index.html.
-pages	Generates a static website for the BookingApp project that can be visited from /target/staging/index.html.
-docker	Does the same thing as -Pdocker of Build commands section.
-without-gui-tests	Does the same thing as-Pskip-gui-tests of Build commands section.
-docs	Generates a jar archive for source code and another for its javadoc in the /target/ directory.
-reset-dependencies	Removes the project dependencies from the local repository. It is useful when you have to remove unused or conflicting dependencies.

Remember that launch files in booking-aggregate execute on the whole project, while the others execute on the single module, so they need to have dependencies installed before starting.

Run Tests from Eclipse

In the BookingApp project three modules contain tests:

• booking-domain-module contains only unit tests.
• booking-business-module contains unit and integration tests.
• booking-ui-module contains both unit, integration and end-to-end tests.

You can run them directly from Eclipse: right click on the module > Run As > JUnit Test. This will execute all the tests of that module.

Before running tests from Eclipse, make sure Docker is turned on and working properly. Then, unit tests doesn't require any additional setting, since they are run with TestContainers; instead, integration and end-to-end tests need a well-configured running instance of MongoDB and once of PostgreSQL. You can start such instances in Docker containers through Docker Compose commands as follows:

docker compose -f docker-compose/MongoDB/docker-compose.yml up
docker compose -f docker-compose/PostgreSQL/docker-compose.yml up

💡 Tip: As you can see, there is another folder inside the docker-compose directory. It also contains a compose file which starts a SonarQube instance in a Docker container. This can be used in conjuction with the -Psonar profile (not previously mentioned) to measure the code quality locally. For more details, read the description in compose files.

Run the BookingApp Application

You can run the BookingApp application through its jar file or using its Docker image.
Remember that the BookingApp application is compatible with both MongoDB and PostgreSQL, so you also need to decide which of them to launch the application with.

Run through Jar

💡 Tip: You can obtain a FatJar of the BookingApp application in two ways: from the build of the BookingApp project or directly by downloading it from Releases.

If you decide to run the BookingApp application through its jar file, you need a running instance of MongoDB or PostgreSQL, depending on which one you prefer.

MongoDB

The MongoDB instance has to be part of a replica set, let's call it rs0. You can start it by running a Docker container with the following command:

docker run -d --name booking-mongo-set -p 27017:27017 mongo:6.0.7 mongod --replSet rs0

After few seconds, the MongoDB instance asks for the replica set initialization (if you remove the detached mode -d from the command above, you can read on terminal an error message just like Cannot use a non-local read concern until replica set is finished initializing). It's the right time to run this other command:

docker exec -it booking-mongo-set mongosh --eval "rs.initiate()"

If the confirmation message ok: 1 appears, then the replica set is also initialized.

📝 Note: This procedure only needs to be applied once, then stop the MongoDB instance through docker stop booking-mongo-set, and start it again (ready for use) with docker start booking-mongo-set.

Once the MongoDB instance is ready, place yourself into the jar file folder (in the BookingApp project it is located in /booking-app/target/), open a Command Prompt and launch the BookingApp application via the following command:

java -jar booking-app-1.1.0-jar-with-dependencies.jar --dbms=MONGO --host=localhost --port=27017 --name=<YOUR_DB_NAME>

The placeholder <YOUR_DB_NAME> must be replaced with a custom name for your database.

PostgreSQL

You can start the PostgreSQL instance by running a Docker container with the following command:

docker run -d --name booking-postgres -p 5432:5432 -e POSTGRES_DB=<YOUR_DB_NAME> -e POSTGRES_USER=<YOUR_USER> -e POSTGRES_PASSWORD=<YOUR_PSDW> postgres:15.3 -N 10

The placeholders <YOUR_DB_NAME>, <YOUR_USER> and <YOUR_PSWD> must be replaced with a custom name and login credentials for your database, respectively. The -N parameter, set to 10, can also be changed: it defines the maximum number of BookingApp instances that can be opened.

📝 Note: Once created, stop the PostgreSQL instance through docker stop booking-postgres, and start it again with docker start booking-postgres.

Once the PostgreSQL instance is ready, place yourself into the jar file folder (in the BookingApp project it is located in /booking-app/target/), open a Command Prompt and launch the BookingApp application with the following command (use the previously defined values for placeholders):

java -jar booking-app-1.1.0-jar-with-dependencies.jar --dbms=POSTGRES --host=localhost --port=5432 --name=<YOUR_DB_NAME> --user=<YOUR_USER> --pswd=<YOUR_PSWD>

Run through Docker

💡 Tip: You can obtain a Docker image of the BookingApp application by building the BookingApp project with the -Pdocker profile. Remember to setup X server environment for Docker before using this mode.

If you decide to run the BookingApp application through its Docker image, place yourself into the project root directory and open a Command Prompt. You can launch the BookingApp application and also a well-configured instance of the chosen DBMS (MongoDB or PostgreSQL) simply with the following Docker Compose command:

docker compose -f <COMPOSE_FILE> up

If your choice is MongoDB, replace <COMPOSE_FILE> with docker-compose-mongo.yml; otherwise, if your choice is PostgreSQL, replace <COMPOSE_FILE> with docker-compose-postgres.yml.

📝 Note: Are you using Windows with WSLg? The all-in-one command becomes: docker compose -f <COMPOSE_FILE> -f docker-compose-wslg.yml up.

Setup X Server Environment for Docker

Desktop GUI applications need a graphical environment for working propertly. Since BookingApp uses the standard Java GUI Swing, it also requires an X display server. Depending on the OS, the X server environment may or may not be native.
The X server must therefore be shared with Docker in order to pass access controls. After that, you will be able to open the BookingApp application inside a Docker container, as required with -Pdocker or when running the BookingApp application with Docker Compose commands.

Linux

Linux already has an X server environment, thus the only thing to do is to share it with Docker. The simplest way is to disable the access control to the X server for the Docker network:

• Run ifconfig for showing all the net interfaces. It may be necessary install the following package for running it: sudo apt install net-tools.
• From the printed list, find out the Docker virtual bridge (let's call it <DOCKER_NET>) which all the containers are connected to. As default it is docker0.
• Run xhost +local:<DOCKER_NET> e.g: xhost +local:docker0.

Now Docker containers can use the X server.

⚠️ Warning: Disabling access control is not a secure choice and you should rely on an authentication method, like xauth. For this reason, when you finish with Docker, it is highly recommanded to remove its access to the X display server by running xhost -local:<DOCKER_NET> e.g: xhost -local:docker0.

Windows

Windows has not a default X server environment, but it can use the one provided by Windows Subsystem for Linux GUI. WSL is necessary to run Docker in Linux containers and is compatible with Windows 10 (Build 19041 or later) and 11.

To use WSLg, just install the last version of WSL from the Microsoft Store or update it if a previous version is already installed through wsl --update.

📝 Note: If Docker is open you may need to restart it after WSL update.

Next, open a Command Prompt and set the DISPLAY variable pointing to the display provided by WSLg:

setx DISPLAY :0.0

By default, the setx command adds variables as user variable in the local environment. To add DISPLAY to the system environment use the -m parameter and run the Command Prompt as Administrator.

Once done, Docker can already use the X display server without any changes to access control. However, if you run the BookingApp application through Docker, you need to override some configurations by adding -f docker-compose-wslg.yml in the Docker Compose command, just after -f <COMPOSE_FILE>.