Vaadin push: Push is not available - push

Question

I have a Maven project, I added vaadin-push as dependency in the pom.xml.
The first problem is in the MainUI class, when I add the annotation #Push(PushMode.MANUAL) it doesn't recognize the PushMode so I am stuck with #Push. When I add it, i get the error message when I access the UI:
{"timestamp":1519112562626,"status":500,"error":"Internal Server Error","exception":"com.vaadin.server.ServiceException","message":"java.lang.IllegalStateException: Push is not available. See previous log messages for more information.","path":"/bp/list"}
I tried to follow the instructions on vaadin website on push so I added a web.xml (I didnt have one previously). I'm not sure whether it is being used. I would prefer to configure this solely by annotations.
<?xml version="1.0" encoding="UTF-8"?>
<web-app
id="WebApp_ID" version="3.0"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
<servlet>
<servlet-name>Business Process UI</servlet-name>
<servlet-class>com.vaadin.server.VaadinServlet</servlet-class>
<init-param>
<param-name>UI</param-name>
<param-value>com.oursys.bpspkpibpcheck.view.MainUI</param-value>
</init-param>
<!-- Enable server push -->
<init-param>
<param-name>pushmode</param-name>
<param-value>automatic</param-value>
</init-param>
<async-supported>true</async-supported>
</servlet>
</web-app>
What I actually want to achieve is to update the UI on a Rest request, I think the Rest part already works apart from the Push:
public class UILister {
private static HashMap<UUID,MainUI> uiByUuid = new HashMap<UUID,MainUI>();
public static void closeUIConnectorFrame(UUID uuid) {
MainUI ui = uiByUuid.get(uuid);
if(ui != null) {
ui.access(new Runnable() {
#Override
public void run() {
ui.closeConnectorFrame();
ui.push();
}}
);
}
}
public static void addUI(UUID uuid, MainUI mainUI) {
uiByUuid.put(uuid, mainUI);
}
}
pom.xml. I removed the vaadin-push since it tells me I am overriding the one configured automatically.
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.leosoftsys</groupId>
<artifactId>bpsp-kpi-bp-check</artifactId>
<version>0.0.1</version>
<packaging>jar</packaging>
<name>bpsp-kpi-bp-check</name>
<description>Business Check For BPS+</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.8.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Dalston.SR4</spring-cloud.version>
<vaadin.version>8.1.1</vaadin.version>
</properties>
<repositories>
<repository>
<id>vaadin-addons</id>
<url>http://maven.vaadin.com/vaadin-addons</url>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-actuator-docs</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-oauth2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.security.oauth</groupId>
<artifactId>spring-security-oauth2</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-security</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zuul</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
</dependency>
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-spring-boot-starter</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/commons-net/commons-net -->
<dependency>
<groupId>commons-net</groupId>
<artifactId>commons-net</artifactId>
<version>3.6</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.jcraft/jsch -->
<dependency>
<groupId>com.jcraft</groupId>
<artifactId>jsch</artifactId>
<version>0.1.54</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.data/spring-data-jpa -->
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.11.6.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.hibernate.javax.persistence/hibernate-jpa-2.0-api -->
<!-- <dependency>
<groupId>org.hibernate.javax.persistence</groupId>
<artifactId>hibernate-jpa-2.0-api</artifactId>
<version>1.0.1.Final</version>
</dependency>
-->
<dependency>
<groupId>org.vaadin.addon</groupId>
<artifactId>confirmdialog</artifactId>
<version>3.2.0</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.module</groupId>
<artifactId>jackson-module-parameter-names</artifactId>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jdk8</artifactId>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.datatype</groupId>
<artifactId>jackson-datatype-jsr310</artifactId>
</dependency>
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-themes</artifactId>
</dependency>
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-sass-compiler</artifactId>
<version>0.9.13</version>
</dependency>
<dependency>
<groupId>net.jodah</groupId>
<artifactId>failsafe</artifactId>
<version>1.0.4</version>
</dependency>
<dependency>
<groupId>org.zalando</groupId>
<artifactId>failsafe-actuator</artifactId>
<version>0.4.1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.json/json -->
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20171018</version>
</dependency>
<!--
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-push</artifactId>
<version>${vaadin.version}</version>
</dependency>
-->
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-bom</artifactId>
<version>${vaadin.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<resources>
<resource>
<directory>src/main/webapp</directory>
</resource>
<resource>
<directory>src/main/resources</directory>
</resource>
</resources>
<testResources>
</testResources>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-maven-plugin</artifactId>
<version>${vaadin.version}</version>
<executions>
<execution>
<goals>
<goal>clean</goal>
<goal>resources</goal>
<goal>update-theme</goal>
<goal>update-widgetset</goal>
<goal>compile-theme</goal>
<goal>compile</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>

Answer 1

In your pom, add
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-push</artifactId>
</dependency>
You don't need to specify a <version> here, since the version is managed by vaadin-bom (bill of materials) which declares the correct version for each artifact (so that it is easier to avoid conflicting dependencies to different versions of the same framework), but importing the BOM doesn't add the dependencies by itself.
<dependency>
<groupId>com.vaadin</groupId>
<artifactId>vaadin-bom</artifactId>
<version>${vaadin.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
I removed the vaadin-push since it tells me I am overriding the one configured automatically.
The one configured automatically refers to the version managed by the BOM. For instance, when one adds a dependency to vaadin-push with a <version> tag, Eclipse it gives the following warning:
Overriding managed version 8.1.1 for vaadin-push