问题描述

问题

Ktor 应用程序的main方法在部署到 AppEngine 时不会被调用。应用程序的主要方法是基于Timer从 API 请求中检索内容并将该信息保存到客户端使用的 Firestore 数据库的逻辑。

此逻辑当前在将Jar部署到 AppEngine 时有效。但是，如果需要端点，使用Ktor实现这一点将节省部署时间并有助于将来证明后端服务。

预期的

一旦将应用程序部署到 AppEngine，就会调用Ktor 应用程序的main方法，类似于在 IntelliJ 中运行应用程序的 main 方法时的调用方式。

实际的

仅在调用应用程序的托管路由后才调用main方法。

IE：https://[yourProjectName].appspot.com

设置

主要方法

import io.ktor.application.Application
fun Application.main() {
    // App logic here.
}

构建.gradle

buildscript {
ext.kotlin_version = '1.3.10'
ext.ktor_version = '1.0.0'
ext.appengine_version = '1.9.60'
ext.appengine_plugin_version = '1.3.4'
ext.junitJupiterVersion  = '5.0.3'

repositories {
    jcenter()
    mavenCentral()
}
dependencies {
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    classpath "com.google.cloud.tools:appengine-gradle-plugin:$appengine_plugin_version"
    classpath 'org.junit.platform:junit-platform-gradle-plugin:1.0.3'
    }
}

plugins {
    id 'org.jetbrains.kotlin.jvm' version '1.2.51'
}

apply plugin: 'java'
apply plugin: 'kotlin'
apply plugin: 'war'
apply plugin: 'com.google.cloud.tools.appengine'

sourceSets {
    main.kotlin.srcDirs = [ 'src/main/kotlin' ]
}

sourceCompatibility = 1.8

repositories {
    jcenter()
    mavenCentral()
    maven { url "https://kotlin.bintray.com/ktor" }
}

dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
    implementation "io.ktor:ktor-server-servlet:$ktor_version"
    implementation "io.ktor:ktor-html-builder:$ktor_version"
    providedCompile "com.google.appengine:appengine:$appengine_version"
    implementation 'com.squareup.retrofit2:retrofit:2.3.0'
    implementation 'com.squareup.retrofit2:converter-gson:2.3.0'
    implementation 'com.squareup.retrofit2:adapter-rxjava:2.3.0'
    implementation 'io.reactivex.rxjava2:rxjava:2.1.1'
    implementation 'com.google.firebase:firebase-admin:6.3.0'
    implementation 'com.google.apis:google-api-services-youtube:v3-rev204-1.23.0'
    testCompile group: 'junit', name: 'junit', version: '4.12'
    // JUnit Jupiter API and TestEngine implementation
    testCompile("org.junit.jupiter:junit-jupiter-api:${junitJupiterVersion}")
    testRuntime("org.junit.jupiter:junit-jupiter-engine:${junitJupiterVersion}")
    testCompile("org.assertj:assertj-core:3.10.0")
    // To avoid compiler warnings about @API annotations in JUnit code
    testCompileOnly('org.apiguardian:apiguardian-api:1.0.0')
}

kotlin.experimental.coroutines = 'enable'

compileKotlin {
    kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
    kotlinOptions.jvmTarget = "1.8"
}

task run(dependsOn: appengineRun)

appengine {
    deploy {
    version = 'media-staging-1201181257pm'
    }
}

src/main/resources/application.conf

ktor {
    application {
        modules = [ InitializationKt.main ]
    }
}

src/main/webapp/WEB-INF/

appengine-web.xml

<?xml version="1.0" encoding="utf-8"?>
<appengine-web-app xmlns="http://appengine.google.com/ns/1.0">
    <threadsafe>true</threadsafe>
    <runtime>java8</runtime>
</appengine-web-app>

web.xml

<?xml version="1.0" encoding="ISO-8859-1" ?>
<web-app 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" version="3.0">
    <servlet>
        <display-name>KtorServlet</display-name>
        <servlet-name>KtorServlet</servlet-name>
    <servlet-class>io.ktor.server.servlet.ServletApplicationEngine</servlet-class>
        <!-- path to application.conf file, required -->
        <init-param>
            <param-name>io.ktor.config</param-name>
            <param-value>application.conf</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>KtorServlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

标签： google-app-enginekotlinktor

google-app-engine - Ktor App 部署到 AppEngine 时未调用 Main 方法

问题描述

问题

预期的

实际的

设置

解决方案

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