my-notes

Build and Package Manager Tools

• Building the code
  • Compiling
  • Compress
  • Hundreds of files into 1 single file
• Artifactory repository
  • Keep artifact in storage
  • to deploy it multiple times, have backup, etc
  • examples:
    • Nexus
    • JFrog Artifactory

What kind of file is the artifact?

Artifact file looks different for each programming language

Example, for Java, the artifact is a JAR file, which includes whole code plus dependencies.

Install Build Tools

Install Java:

# using the one from the package manager
sudo apt install default-jdk

# setting JAVA_HOME variable (seems to be important for some tools)
# put the code below in your ~/.profile
if [ -d "/usr/lib/jvm/default-java/bin" ]; then
    JAVA_HOME="/usr/lib/jvm/default-java"
    PATH="$JAVA_HOME/bin:$PATH"
fi

Install Maven

See instructions in https://maven.apache.org/install.html

Install Gradle

I just used IntelliJ.

Install Node + npm

I prefer to use Node Version Manager.

Download IntelliJ

Download page: https://www.jetbrains.com/idea/download/

The Community version has the needed tools.

Build an Artifact

• Build tools for Java applications:
  • Maven (uses XML)
  • Gradle (uses Groovy)

With Gradle

The ./gradlew present in the Nana’s repo is enough to build the project.

Executing ./gradlew build will generate the ./build/ folder and the .jar file will be placed in ./build/libs/.

With Maven

Config the pom.xml file with the <build> tag. Then:

mvn install

The .jar file will be placed in ./target/ folder.

Build Tools for Development

Managing dependencies:

• With Maven:
  • file: pom.xml
• With Gradle:
  • file: build.gradle
• repository: https://mvnrepository.com/

Run the Application

Command to run a .jar file:

java -jar <file.jar>

Build JS Application

Backend

• no special artifact type
• npm or yarn for dependency manager
• npm repository for dependencies

# install dependencies (inside projects directory)
npm install

# when the package.json is properly configured
npm start   # start the application
npm stop    # stop the application
npm test    # run the tests
npm publish # publish the artifact

# create an artifact file
npm pack    # creates a tar file

What does the zip/tar file include?

• application code, but NOT the dependencies.
• to run the app on the server:
  • you must install the dependencies first
  • unpack zip/tar
  • run the App

Frontend

• Frontend/React code needs to be transpiled
• code needs to be compressed/minified
• Separate tools for that - build tools/bundler (e.g.: webpack, grunt, etc.)

# install dependencies (inside projects directory)
npm install

# assuming webpack is installed and "build" in package.json calls webpack
# and it bundles the code minified/transpiled.
npm run build

When working with Java in the backend and React in the frontend, it’s possible to:

• bundle the App with Webpack
• manage dependencies with npm or yarn
• package everything into a WAR file

Common Concepts and Differences of Build Tools

language	dependency manager
Java	Maven or Gradle
JavaScript	npm or yarn
Python	pip

Pattern in all these tools:

• dependency file
• repository for dependencies
• command line tool
• package managers

Publish an Artifact

Publish artifact into a artifact repository.

• build tools have commands for that
• then you can download (curl, wget) it anywhere

Build Tools & Docker

• No need to build and move different artifact types (e.g.: jar, war, zip).
  • Just one artifact type: a docker image.
• No need for a repository for each file type.
  • Just one, for Docker images.
• No need to install dependencies on the server.
  • Just execute install command inside Docker image.
• Docker makes it easier to standardize the way to publish software artifacts.
• Docker image is an alternative for all other artifact types.

• You don’t need to install npm or java on the server. Execute everything in the image.

• You still need to build the Apps, and then create the Docker image (via Dockerfile).

Build Tools for DevOps

Why should a DevOps Engineer know these build tools?

• help developers for building the application
• because you know where and how it will run
  • build Docker image > push to repo > run on server
• you need to configure the build automation tool, CI/CD pipeline
  • install dependencies, run tests, build/bundle the app, push to repo
  • you DON’T run the app locally
• you need to execute tests on the build servers
• build and package into Docker image.