Blank Pages

Flow
1

I added the necessary Vaadin dependencies (vaadin-core and vaadin-spring-boot-starter ) to my project, but when I try to access a view or even swagger, I only see a blank white page with these errors:

Screenshot 2024-08-03 211540
Screenshot 2024-08-03 2115401083×523 59.1 KB

Additional Information:

  • Spring Boot version: 3.0.2
  • Java version: 17
  • Vaadin version: 24.4.7

Here’s my complete pom.xml file for reference:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.0.2</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>DCS</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>DCS</name>
    <description>DCS Development Env</description>
    <properties>
        <java.version>17</java.version>
        <maven.compiler.release>17</maven.compiler.release>
        <vaadin.version>24.4.7</vaadin.version>

    </properties>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/net.sf.jasperreports/jasperreports -->
        <dependency>
            <groupId>net.sf.jasperreports</groupId>
            <artifactId>jasperreports</artifactId>
            <version>6.21.2</version>
        </dependency>
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.7</version> <!-- or the latest version available -->
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <!-- AWS Uploader -->
        <dependency>
            <groupId>com.amazonaws</groupId>
            <artifactId>aws-java-sdk</artifactId>
            <version>1.11.133</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-crypto</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
        </dependency>
        <dependency>
            <groupId>com.github.ulisesbocchio</groupId>
            <artifactId>jasypt-spring-boot-starter</artifactId>
            <version>3.0.3</version>
        </dependency>
        <dependency>
            <groupId>org.passay</groupId>
            <artifactId>passay</artifactId>
            <version>1.6.2</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-api</artifactId>
            <version>0.11.5</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-impl</artifactId>
            <version>0.11.5</version>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt-jackson</artifactId>
            <version>0.11.5</version>
        </dependency>
        <dependency>
            <groupId>javax.xml.bind</groupId>
            <artifactId>jaxb-api</artifactId>
            <version>2.3.1</version> <!-- Or the version compatible with your Java version -->
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-crypto</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <!-- Spring Data JPA -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <!-- Spring Boot Web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- Spring DevTools -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.23</version>
        </dependency>
        <dependency>
            <groupId>org.springdoc</groupId>
            <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
            <version>2.0.2</version>
        </dependency>
        <dependency>
            <groupId>org.mariadb.jdbc</groupId>
            <artifactId>mariadb-java-client</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>io.jsonwebtoken</groupId>
            <artifactId>jjwt</artifactId>
            <version>0.9.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
            <version>2.3.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.modelmapper</groupId>
            <artifactId>modelmapper</artifactId>
            <version>3.1.1</version>
        </dependency>


        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.6</version>
        </dependency>
        <dependency>
            <groupId>com.google.firebase</groupId>
            <artifactId>firebase-admin</artifactId>
            <version>7.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.javers</groupId>
            <artifactId>javers-core</artifactId>
            <version>6.2.3</version>
        </dependency>

        <dependency>
            <groupId>com.google.code.geocoder-java</groupId>
            <artifactId>geocoder-java</artifactId>
            <version>0.16</version>
        </dependency>
        <!-- H2 Database -->

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.mapstruct</groupId>
            <artifactId>mapstruct</artifactId>
            <version>1.4.2.Final</version> <!-- Replace with the latest version -->
        </dependency>

        <dependency>
            <groupId>org.hibernate.validator</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>8.0.0.Final</version>
        </dependency>
        <dependency>
            <groupId>commons-validator</groupId>
            <artifactId>commons-validator</artifactId>
            <version>1.7</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-csv</artifactId>
            <version>1.9.0</version> <!-- Or the latest version -->
        </dependency>
        <dependency>
            <groupId>com.opencsv</groupId>
            <artifactId>opencsv</artifactId>
            <version>5.5.2</version>
        </dependency>

        <!-- Jasper Reports -->
        <!--<dependency>-->
        <!--    <groupId>net.sf.jasperreports</groupId>-->
        <!--    <artifactId>jasperreports</artifactId>-->
        <!--    <version>6.9.0</version>-->
        <!--</dependency>-->
        <!-- Spring Boot Web Starter -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- Spring Boot Mail Starter -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-core</artifactId>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-spring-boot-starter</artifactId>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>

        </plugins>

    </build>
    <repositories>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.vaadin</groupId>
                <artifactId>vaadin-bom</artifactId>
                <version>${vaadin.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>
</project>

Can you identify any issues in my pom.xml configuration that might be causing the blank page and errors?

2

Maybe it will not solve the issue but at least:

Vaadin 24.4 requires Spring Boot 3.2 or newer

commons-io 2.7 will likely cause issues, since Flow uses 2.16

3

Tried Spring 3.2.8 and commons-io 2.16, no luck.

4

I’m encountering an issue where controllers returning views are not rendering correctly, while REST APIs returning JSON objects work as expected. This problem consistently occurs, and the error messages (as shown in the image) remain the same.

5

Compare your pom.xml with for example an project from start.vaadin.com - you are missing crucial configurations for the maven plugins.

6

I already tried that Christian but still no luck. It’s something with the rendering process. I managed to get swagger to work by excluding it using vaadin.excludeUrls=/swagger-ui/** as mentioned here. But the rest of the views are still not rendering.

7

How does your Spring security configuration look like? Maybe you are blocking some Vaadin internal request

8

permittedPathUris includes /ui/** which is the value set to vaadin.url-mapping property in the properties file.

@Bean
	public SecurityFilterChain securityFilterChain(HttpSecurity http) throws Exception {

		String[] userRoles = List.of("ADMIN", "USER").toArray(String[]::new);
		String[] permittedPathUris = PathUri.PermittedPathUris.toArray(String[]::new);
		log.info("permittedPathUris : " + Arrays.toString(permittedPathUris));

		http
				.csrf().disable()
				.cors().and()
				.addFilterBefore(corsFilter, UsernamePasswordAuthenticationFilter.class)
				.authorizeHttpRequests()
				.requestMatchers(permittedPathUris)
				.permitAll()
				.requestMatchers("/api/v1/**")
				.hasAnyAuthority(userRoles)
				.anyRequest().authenticated()
				.and()
				.exceptionHandling()
				.accessDeniedHandler(accessDeniedHandler())
				.and()
				.sessionManagement()
				.sessionCreationPolicy(SessionCreationPolicy.STATELESS)
				.and()
				.authenticationProvider(authenticationProvider)
				.addFilterBefore(jwtAuthFilter, UsernamePasswordAuthenticationFilter.class)
				.headers()
				.xssProtection()
				.and()
				.contentSecurityPolicy("script-src 'self'");

		return http.build();
	}
9

You should probably review your content security policy according to Frequently Reported Issues | Advanced Security Topics | Security | Flow | Vaadin Docs

10

Ok i will take a look at it. BTW the page keeps on loading while displaying a white screen.

11

Brilliant Marco, It was the content security policy in the security configuration that caused the white screen.

Thanks alot.