docker-compose selenium-grid，maven，java。用于设置功能的空虚拟池

Question

我正在尝试在docker容器中运行selenium java项目：

我的docker-compose.yml：

version: '3'
services:
  hub:
    image: selenium/hub:3.141.59-vanadium
    container_name: hub
    ports:
      - "4444:4444"

  firefox:
    image: selenium/node-firefox:3.141.59-vanadium
    volumes:
      - /dev/shm:/dev/shm
    depends_on:
      - hub
    environment:
      - HUB_HOST=hub
      - HUB_PORT=4444

  mongo:
    image: 'mongo:4.0.4'
    ports:
      - '27017:27017'
    volumes:
      - 'mongo:/data/db'

  app:
    image: app:latest
    ports:
      - "5050:5050"
    depends_on:
      - mongo
      - firefox

volumes:
  mongo:

my Dockerfile for java app：

#
# Build stage
#
FROM maven:3.6.0-jdk-11-slim AS build
COPY src /home/app/src
COPY pom.xml /home/app

# build jar with dependencies
RUN mvn -f /home/app/pom.xml clean compile assembly:single

#
# Package stage
#
FROM openjdk:11-jre-slim
COPY --from=build /home/app/target/app-1.0-SNAPSHOT-jar-with-dependencies.jar /usr/local/lib/app.jar
EXPOSE 5001
ENTRYPOINT ["java","-jar","/usr/local/lib/app.jar", "docker"]

来自pom.xml的插件：

    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>7</source>
                <target>7</target>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>exec-maven-plugin</artifactId>
            <version>1.6.0</version>
            <configuration>
                <mainClass>learn.selenium.Main</mainClass>
            </configuration>
        </plugin>
        <plugin>
            <!-- Build an executable JAR -->
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-jar-plugin</artifactId>
            <version>3.0.0</version>
            <configuration>
                <archive>
                    <manifest>
                        <addClasspath>true</addClasspath>
                        <classpathPrefix>lib/</classpathPrefix>
                        <mainClass>learn.selenium.Main</mainClass>
                    </manifest>
                </archive>
            </configuration>
        </plugin>
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <configuration>
                <archive>
                    <manifest>
                        <mainClass>learn.selenium.Main</mainClass>
                    </manifest>
                </archive>
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
            </configuration>
        </plugin>
    </plugins>

从代码连接到selenium：

Capabilities firefoxCapabilities = new FirefoxOptions();
WebDriver driver = new RemoteWebDriver(new URL("http://hub:4444/wd/hub"), firefoxCapabilities);

当我尝试运行只包含selenium内容的docker compose时，它看起来工作得很好。但是当我将java app添加到容器中时，我得到了以下错误：

hub        | org.openqa.grid.common.exception.GridException: Empty pool of VM for setup Capabilities {acceptInsecureCerts: true, browserName: firefox, moz:firefoxOptions: {args : {}}}
hub        |    at org.openqa.grid.internal.ProxySet.verifyAbilityToHandleDesiredCapabilities(ProxySet.java:146)
...
app_1  | org.openqa.selenium.WebDriverException: Error forwarding the new session Empty pool of VM for setup Capabilities {acceptInsecureCerts: true, browserName: firefox, moz:firefoxOptions: {args: [], prefs: {}}}
app_1  | Command duration or timeout: 453 milliseconds
app_1  |    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

以下是网格控制台：

​

你能指点我哪里做错了吗？

Answer 1

好吧，看起来，当我尝试连接集线器时，集线器还没有准备好。因此，为了测试，我添加了Thread.sleep(1000)，它起作用了。我认为这里的正确方法是ping集线器，并在状态更改为ready后继续进行web驱动程序初始化。对我来说，这很奇怪，因为我添加了

 depends_on:
  - mongo
  - firefox

所以我希望我的java项目能在selenium相关的容器启动并准备好之后运行。