PSQLException：连接尝试失败-Appengine部署错误

Question

将我的Maven Spring-boot Java应用程序部署到Google App Engine时遇到的问题。

我的 pom.xml 是：

<?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>
    <parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.1.RELEASE</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>
<groupId>com.sample</groupId>
<artifactId>catapi</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>catapi</name>
<packaging>war</packaging>
<description>Demo project for Spring Boot</description>

<properties>
    <java.version>1.8</java.version>
</properties>

<dependencyManagement>
    <dependencies>
      <dependency>
      <groupId>org.springframework.cloud</groupId>
      <artifactId>spring-cloud-gcp-dependencies</artifactId>
      <version>1.0.0.RC1</version>
      <type>pom</type>
      <scope>import</scope>
      </dependency>
  </dependencies>
</dependencyManagement>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-jdbc</artifactId>
    </dependency>

    <!--dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-gcp-starter-sql</artifactId>
        <version>1.0.0.BUILD-SNAPSHOT</version>
    </dependency-->

    <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <scope>runtime</scope>
        <version>42.1.1</version>
    </dependency>

    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.1.0</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>jul-to-slf4j</artifactId>
      <scope>provided</scope>
    </dependency>

    <dependency>
        <groupId>com.google.cloud.sql</groupId>
        <artifactId>postgres-socket-factory</artifactId>
        <version>1.0.4</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

<repositories>
  <!-- Use Spring Milestone Repository -->
  <repository>
    <id>repository.spring.milestone</id>
    <name>Spring Milestones Repository</name>
    <url>http://repo.spring.io/milestone</url>
  </repository>
</repositories>

<build>
    <plugins>
        <plugin>
          <groupId>com.google.cloud.tools</groupId>
          <artifactId>appengine-maven-plugin</artifactId>
          <version>1.3.2</version>
          <configuration>
            <version>1</version>
          </configuration>
        </plugin>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

我的 appengine-web.xml 是：

<appengine-web-app xmlns="http://appengine.google.com/ns/1.0">
  <version>1</version>
  <threadsafe>true</threadsafe>
  <runtime>java8</runtime>
</appengine-web-app>

我在主应用程序下添加了 ServletInitializer.java ，这使其在 mvn appengine：run 上运行得非常好。 在 mvn spring-boot：run 中也可以正常工作。

我的 application.properties 是：

spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.PostgreSQLDialect
spring.jpa.hibernate.ddl-auto=create
spring.jpa.hibernate.show-sql=true

spring.datasource.url=jdbc:postgresql://35.200.222.222:5432/test
spring.datasource.username=postgres
spring.datasource.password=Welcome1!

spring.datasource.initialization-mode=always
spring.datasource.initialize=true
spring.datasource.schema=classpath:/schema.sql
spring.datasource.continue-on-error=true

错误是：

PSQLException: The connection attempt failed.
org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl (ConnectionFactoryImpl.java:275)

错误日志是：

org.postgresql.util.PSQLException: The connection attempt failed.
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl (ConnectionFactoryImpl.java:275)
at org.postgresql.core.ConnectionFactory.openConnection (ConnectionFactory.java:49)
at org.postgresql.jdbc.PgConnection.<init> (PgConnection.java:194)
at org.postgresql.Driver.makeConnection (Driver.java:450)
at org.postgresql.Driver.connect (Driver.java:252)
at com.zaxxer.hikari.util.DriverDataSource.getConnection (DriverDataSource.java:136)
at com.zaxxer.hikari.pool.PoolBase.newConnection (PoolBase.java:369)
at com.zaxxer.hikari.pool.PoolBase.newPoolEntry (PoolBase.java:198)
at com.zaxxer.hikari.pool.HikariPool.createPoolEntry (HikariPool.java:467)
at com.zaxxer.hikari.pool.HikariPool.checkFailFast (HikariPool.java:541)
at com.zaxxer.hikari.pool.HikariPool.<init> (HikariPool.java:115)
at com.zaxxer.hikari.HikariDataSource.getConnection (HikariDataSource.java:112)
at org.springframework.jdbc.datasource.DataSourceUtils.fetchConnection (DataSourceUtils.java:151)
at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection (DataSourceUtils.java:115)
at org.springframework.jdbc.datasource.DataSourceUtils.getConnection (DataSourceUtils.java:78)
at org.springframework.jdbc.datasource.init.DatabasePopulatorUtils.execute (DatabasePopulatorUtils.java:46)
at org.springframework.boot.autoconfigure.jdbc.DataSourceInitializer.runScripts (DataSourceInitializer.java:210)
at org.springframework.boot.autoconfigure.jdbc.DataSourceInitializer.createSchema (DataSourceInitializer.java:104)
at org.springframework.boot.autoconfigure.jdbc.DataSourceInitializerInvoker.afterPropertiesSet (DataSourceInitializerInvoker.java:64)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods (AbstractAutowireCapableBeanFactory.java:1804)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean (AbstractAutowireCapableBeanFactory.java:1741)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean (AbstractAutowireCapableBeanFactory.java:576)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean (AbstractAutowireCapableBeanFactory.java:498)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0 (AbstractBeanFactory.java:320)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton (DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean (AbstractBeanFactory.java:318)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean (AbstractBeanFactory.java:224)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveNamedBean (DefaultListableBeanFactory.java:1112)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveBean (DefaultListableBeanFactory.java:407)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean (DefaultListableBeanFactory.java:341)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBean (DefaultListableBeanFactory.java:335)
at org.springframework.boot.autoconfigure.jdbc.DataSourceInitializerPostProcessor.postProcessAfterInitialization (DataSourceInitializerPostProcessor.java:55)

完整错误堆栈跟踪图像： error1 error2 error3

点击应用程序网址后，浏览器如下所示：browser_error

Error: Server Error
The server encountered an error and could not complete your request.
Please try again in 30 seconds.

有人可以帮助我解决其他需要改变的地方吗？