Maven exec plugin to invoke npm install and build. Integrating Spring Boot and Angular builds.

maven-npm-install-pom.xml

      <plugin>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-maven-plugin</artifactId>
        <configuration>
          <executable>true</executable>
        </configuration>
      </plugin>
      <plugin>
        <artifactId>maven-resources-plugin</artifactId>
        <executions>
          <execution>
            <id>copy-resources</id>
            <phase>validate</phase>
            <goals>
              <goal>copy-resources</goal>
            </goals>
            <configuration>
              <outputDirectory>${project.build.directory}/classes/static</outputDirectory>
              <resources>
                <resource>
                  <directory>src/main/frontend/dist</directory>
                </resource>
              </resources>
            </configuration>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <groupId>org.codehaus.mojo</groupId>
        <artifactId>exec-maven-plugin</artifactId>
        <version>1.6.0</version>
        <executions>
          <execution>
            <id>npm-install</id>
            <phase>prepare-package</phase>
            <goals>
              <goal>exec</goal>
            </goals>
            <configuration>
              <executable>npm</executable>
              <arguments>
                <argument>install</argument>
                <argument>--silent</argument>
              </arguments>
              <workingDirectory>src/main/frontend</workingDirectory>
            </configuration>
          </execution>
          <execution>
            <id>npm-build</id>
            <phase>prepare-package</phase>
            <goals>
              <goal>exec</goal>
            </goals>
            <configuration>
              <executable>npm</executable>
              <arguments>
                <argument>run</argument>
                <argument>build</argument>
              </arguments>
              <workingDirectory>src/main/frontend</workingDirectory>
            </configuration>
          </execution>
        </executions>
      </plugin>