Production Build
To create a production build, run the following command:
mvn clean package -Pproduction
This builds a JAR
or WAR
file with all the dependencies and transpiled front-end resources, ready to be deployed.
The file can be found in the target
folder after the build completes.
Enabling Production Builds
The production build command should work out of the box for Vaadin starter projects, for example projects that are generated with https://start.vaadin.com.
The starter projects come with the necessary Maven configuration.
If you have created your project’s pom.xml
file manually, add the following Maven profile to enable production builds:
<profiles>
<profile>
<id>production</id>
<properties>
<vaadin.productionMode>true</vaadin.productionMode>
</properties>
<!--
.. configuration depending on environment ..
-->
<executions>
<execution>
<goals>
<goal>build-frontend</goal>
</goals>
<phase>compile</phase>
</execution>
</executions>
<!--
.. more configuration ..
-->
</profile>
</profiles>
The actual content of the profile depend on what environment your application is running in, but all the variations do two things:
-
Set the property
vaadin.productionMode
totrue
-
Call the Maven goal
vaadin:build-frontend
. The Maven goalvaadin:prepare-frontend
is also required, but that’s often declared already in the development build.
Once the Maven profile is added, you can call the production build command.
If you don’t have the production Maven profile in your pom.xml
file, the easiest way to get it’s to get a project base from https://start.vaadin.com (for Spring Boot projects) or from https://vaadin.com/hello-world-starters (for other stacks such as Jakarta EE, or plain Java), and then copy the production profile from the downloaded pom.xml
file.
Having the production build as a separate Maven profile is recommended to avoid unexpected problems due to production settings during development.
Note
|
Building for 64-bit
If your operating system is 64-bit, make sure to use a 64-bit JDK installation as well.
|
Excluding the Development Server Module
The Vite server integration and live reload features, which are available only in development builds, are contained in the module com.vaadin:vaadin-dev-server
.
When building the application for production, it’s recommended to exclude this module.
This can be achieved by adding the following dependency exclusion to the <dependencies>
section in the production
profile:
<profiles>
<profile>
<id>production</id>
<!-- above production build configuration -->
<dependencies>
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin</artifactId>
<exclusions>
<exclusion>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-dev-server</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
</profile>
</profiles>
This results in less code and fewer dependency libraries being bundled in the production application.
Transpilation and Bundling
Transpilation in Vaadin means converting all ES6 JavaScript to ES5 JavaScript format for older browsers. All Vaadin components are written using ES6, and consist of several JavaScript and CSS files. Transpilation makes sure this newer JavaScript code also works in browsers which don’t support all the latest JavaScript features.
During the build, minimization is done to make the files smaller. When minifying code, it’s often obfuscated, which makes it harder to read, hence this isn’t done for development builds.
Bundling is an optimization where multiple files are merged to a single collection, so that the browser doesn’t need to request so many files from the server. This makes the application load faster.
Plugin Goals and Goal Parameters
prepare-frontend
This goal validates whether the node
and npm
tools are installed and not too old (node
version 16.14
or later and npm
version 8.3
or later), and also installs them automatically to the .vaadin
folder in the user’s home directory if they are missing.
If they are installed globally but too old, there is an error message suggesting that you install newer versions instead.
Node.js is needed to run npm
to install front-end dependencies and Vite, which bundles the front-end files served to the client.
In addition, it visits all resources used by the application and copies them under the node_modules
folder, so they are available when vite
builds the frontend.
It also creates or updates the package.json
, vite.config.ts
and vite.generated.ts
files.
Goal Parameters
-
includes
(default:**/*.js,**/*.css
): Comma-separated wildcards for files and directories that should be copied. The default is only.js
and.css
files. -
npmFolder
(default:${project.basedir}
): The folder where thepackage.json
file is located. The default is the project root folder. -
generatedFolder
(default:${project.build.directory}/frontend/
): The folder where Flow puts generated files that are used by Vite. -
require.home.node
(default:false
): If set totrue
, always prefer Node.js automatically downloaded and installed into the.vaadin
directory in the user’s home directory.
build-frontend
This goal builds the front-end bundle. This is a complex process involving several steps:
-
update
package.json
with all the@NpmPackage
annotation values found in the classpath and automatically install these dependencies. -
update the JavaScript files containing code for importing everything used in the application. These files are generated in the
target/frontend
folder, and are used as the entry point of the application. -
create
vite.config.ts
if not found, or update it if some project parameters have changed. -
generate JavaScript bundles, chunks and transpile to ES5 using
vite
server. The target folder forWAR
packaging istarget/${artifactId}-${version}/build
. ForJAR
packaging, it’starget/classes/META-INF/resources/build
.
Goal Parameters
npmFolder
(default:${project.basedir}
-
The folder where the
package.json
file is located. The default is the project root folder. generatedFolder
(default:${project.build.directory}/frontend/
)-
The folder where Flow puts generated files that are used by Vite.
frontendDirectory
(default:${project.basedir}/frontend
)-
The directory with the project’s front-end source files.
generateBundle
(default:true
)-
Whether to generate a bundle from the project front-end sources.
runNpmInstall
(default:true
)-
Whether to run
pnpm install
(ornpm install
, depending on pnpmEnable parameter value) after updating dependencies. generateEmbeddableWebComponents
(default:true
)-
Whether to generate embedded web components from
WebComponentExporter
inheritors. optimizeBundle
(default:true
)-
Whether to include only front-end resources used from application entry points (the default) or to include all resources found on the class path. Should normally be left to the default, but a value of
false
can be useful for faster production builds or debugging discrepancies between development and production builds. pnpmEnable
(default:false
)-
Whether to use the
pnpm
ornpm
tool to handle front-end resources. The default isnpm
. useGlobalPnpm
(default:false
)-
Whether to use a globally installed
pnpm
tool instead of the default supported version ofpnpm
.
clean-frontend
This goal removes files that may cause inconsistencies when changing versions.
It’s suggested to not add the goal as a default to pom.xml
and instead use it with mvn vaadin:clean-frontend
when necessary.
Executing the clean-frontend
goal removes:
-
the package lock file;
-
the generated front-end folder (by default
frontend/generated
); -
the
node_modules
folder (this might need manual deletion).
The goal also cleans all dependencies that are framework-managed, and any dependencies that target the build folder from the package.json
file.
The clean-frontend
goal supports the same parameters as prepare-frontend
.