Kotlin整合Vertx开发Web应用

约定不等于承诺〃 2022-04-23 15:04 221阅读 0赞

今天我们尝试Kotlin整合Vertx，并决定建立一个非常简单的Web应用程序，使用Kotlin和Vertx作为编程语言进行编码构建。

#### 生成项目 ####

--------------------

*  打开控制台窗口执行以下代码进行生成一个maven项目

mvn archetype:generate -DgroupId=com.edurt.kvi -DartifactId=kotlin-vertx-integration -DarchetypeArtifactId=maven-archetype-quickstart -Dversion=1.0.0 -DinteractiveMode=false

*  修改pom.xml增加java和kotlin的支持

<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/maven-v4_0_0.xsd">
    
        <modelVersion>4.0.0</modelVersion>
        <groupId>com.edurt.kvi</groupId>
        <artifactId>kotlin-vertx-integration</artifactId>
        <packaging>jar</packaging>
        <version>1.0.0</version>
    
        <name>kotlin-vertx-integration</name>
        <description>Kotlin Vertx Integration is a open source kotlin vertx integration example.</description>
    
        
        <properties>
            
            <dependency.kotlin.version>1.2.71</dependency.kotlin.version>
            <dependency.vertx.ersion>3.4.1</dependency.vertx.ersion>
            
            <plugin.maven.compiler.version>3.3</plugin.maven.compiler.version>
            <plugin.maven.javadoc.version>2.10.4</plugin.maven.javadoc.version>
            <plugin.maven.kotlin.version>1.2.71</plugin.maven.kotlin.version>
            
            <environment.compile.java.version>1.8</environment.compile.java.version>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
            <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
            <java.version>1.8</java.version>
            <jvmTarget>1.8</jvmTarget>
        </properties>
    
        
        <dependencies>
            
            <dependency>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-stdlib-jdk8</artifactId>
                <version>${dependency.kotlin.version}</version>
            </dependency>
            <dependency>
                <groupId>org.jetbrains.kotlin</groupId>
                <artifactId>kotlin-reflect</artifactId>
                <version>${dependency.kotlin.version}</version>
            </dependency>
            
            <dependency>
                <groupId>io.vertx</groupId>
                <artifactId>vertx-core</artifactId>
                <version>${dependency.vertx.ersion}</version>
            </dependency>
            <dependency>
                <groupId>io.vertx</groupId>
                <artifactId>vertx-web</artifactId>
                <version>${dependency.vertx.ersion}</version>
            </dependency>
        </dependencies>
    
        
        <prerequisites>
            <maven>3.5.0</maven>
        </prerequisites>
    
        
        <build>
            <sourceDirectory>${project.basedir}/src/main/kotlin</sourceDirectory>
            <testSourceDirectory>${project.basedir}/src/test/kotlin</testSourceDirectory>
            <plugins>
                <plugin>
                    <artifactId>kotlin-maven-plugin</artifactId>
                    <groupId>org.jetbrains.kotlin</groupId>
                    <configuration>
                        <args>
                            <arg>-Xjsr305=strict</arg>
                        </args>
                        <compilerPlugins>
                            <plugin>spring</plugin>
                            <plugin>jpa</plugin>
                            <plugin>all-open</plugin>
                        </compilerPlugins>
                        <pluginOptions>
                            <option>all-open:annotation=javax.persistence.Entity</option>
                        </pluginOptions>
                    </configuration>
                    <dependencies>
                        <dependency>
                            <groupId>org.jetbrains.kotlin</groupId>
                            <artifactId>kotlin-maven-allopen</artifactId>
                            <version>${plugin.maven.kotlin.version}</version>
                        </dependency>
                        <dependency>
                            <groupId>org.jetbrains.kotlin</groupId>
                            <artifactId>kotlin-maven-noarg</artifactId>
                            <version>${plugin.maven.kotlin.version}</version>
                        </dependency>
                    </dependencies>
                    <executions>
                        <execution>
                            <id>kapt</id>
                            <goals>
                                <goal>kapt</goal>
                            </goals>
                            <configuration>
                                <sourceDirs>
                                    <sourceDir>src/main/kotlin</sourceDir>
                                </sourceDirs>
                                <annotationProcessorPaths>
                                    <annotationProcessorPath>
                                        <groupId>org.springframework.boot</groupId>
                                        <artifactId>spring-boot-configuration-processor</artifactId>
                                        <version>${project.parent.version}</version>
                                    </annotationProcessorPath>
                                </annotationProcessorPaths>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>${plugin.maven.compiler.version}</version>
                    <configuration>
                        <source>${environment.compile.java.version}</source>
                        <target>${environment.compile.java.version}</target>
                    </configuration>
                </plugin>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-javadoc-plugin</artifactId>
                    <version>${plugin.maven.javadoc.version}</version>
                    <configuration>
                        <aggregate>true</aggregate>
                        
                        <tags>
                            <tag>
                                <name>Description</name>
                                <placement>test</placement>
                                <head>description</head>
                            </tag>
                        </tags>
                        
                        <additionalparam>-Xdoclint:none</additionalparam>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    
    </project>

#### 添加Vertx实例 ####

--------------------

*  创建CoreVerticle类文件

package com.edurt.kvi.core
    
    import io.vertx.core.AbstractVerticle
    import io.vertx.core.Future
    import io.vertx.core.Handler
    import io.vertx.ext.web.Router
    import io.vertx.ext.web.RoutingContext
    
    class CoreVerticle : AbstractVerticle() {
    
        override fun start(startFuture: Future<Void>?) {
            val router = createRouter()
            val port = config().getInteger("http.port", 8080)
            vertx.createHttpServer()
                    .requestHandler { router.accept(it) }
                    .listen(port) { result ->
                        if (result.succeeded()) {
                            startFuture?.complete()
                        } else {
                            startFuture?.fail(result.cause())
                        }
                    }
        }
    
        private fun createRouter() = Router.router(vertx).apply {
            get("/").handler(handlerRoot)
        }
    
        /**
         * create router instance
         */
        val handlerRoot = Handler<RoutingContext> { req ->
            req.response().end("Hello Kotlin Vertx Integration!")
        }
    
    }

*  设置启动类

package com.edurt.kvi
    
    import com.edurt.kvi.core.CoreVerticle
    import io.vertx.core.Vertx
    
    class KotlinVertxIntegration
    
    fun main(args: Array<String>) {
        val vertx = Vertx.vertx()
        vertx.deployVerticle(CoreVerticle::class.java.name)
    }

以上操作在`vertx.deployVerticle`阶段执行了部署Verticle的操作，即部署CoreVerticle。

*  启动应用后浏览器访问[http://localhost:8080][http_localhost_8080]出现以下页面

![blob.jpg][]

#### 增加页面渲染功能 ####

--------------------

*  修改pom.xml文件增加页面依赖

<dependency.slf4j.version>1.7.25</dependency.slf4j.version>
    
    <dependency>
        <groupId>io.vertx</groupId>
        <artifactId>vertx-web-templ-thymeleaf</artifactId>
        <version>${dependency.vertx.ersion}</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>${dependency.slf4j.version}</version>
    </dependency>

*  增加页面渲染文件

package com.edurt.kvi.router
    
    import io.vertx.ext.web.Router
    import io.vertx.ext.web.RoutingContext
    import io.vertx.ext.web.templ.ThymeleafTemplateEngine
    import org.thymeleaf.templatemode.TemplateMode
    
    class HomeViewRouter
    
    fun index(r: Router) {
        val engine = ThymeleafTemplateEngine.create().setMode(TemplateMode.HTML)
        r.get("/index.html").handler { c ->
            render(c, engine, "templates/index.html")
        }
    }
    
    fun render(c: RoutingContext, engine: ThymeleafTemplateEngine, templ: String) {
        engine.render(c, templ) { res ->
            if (res.succeeded()) {
                c.response().end(res.result())
            } else {
                c.fail(res.cause())
            }
        }
    }

*  在templates/index.html目录下创建页面文件

<!DOCTYPE html SYSTEM "http://www.thymeleaf.org/dtd/xhtml1-strict-thymeleaf-4.dtd">
    <html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>Kotlin Vertx Integration</title>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
    </head>
    
    <body>
    <p>Welcome To Kotlin Vertx Integration!</p>
    </body>
    </html>

*  修改CoreVerticle增加页面跳转

package com.edurt.kvi.core
    
    import com.edurt.kvi.router.index
    import io.vertx.core.AbstractVerticle
    import io.vertx.core.Future
    import io.vertx.core.Handler
    import io.vertx.core.Vertx
    import io.vertx.core.http.HttpServerResponse
    import io.vertx.ext.web.Router
    import io.vertx.ext.web.RoutingContext
    
    class CoreVerticle : AbstractVerticle() {
    
        override fun start() {
            val router = createRouter(vertx)
    
            // go to index page
            index(router)
    
            vertx.createHttpServer().requestHandler { handler -> router.accept(handler) }.listen(8080)
    
    //        val port = config().getInteger("http.port", 8080)
    //        vertx.createHttpServer()
    //                .requestHandler { router.accept(it) }
    //                .listen(port) { result ->
    //                    if (result.succeeded()) {
    //                        startFuture?.complete()
    //                    } else {
    //                        startFuture?.fail(result.cause())
    //                    }
    //                }
        }
    
        private fun createRouter() = Router.router(vertx).apply {
            get("/").handler(handlerRoot)
        }
    
        /**
         * create router instance
         */
        val handlerRoot = Handler<RoutingContext> { req ->
            req.response().end("Hello Kotlin Vertx Integration!")
        }
    
        fun createRouter(v: Vertx): Router {
            var router = Router.router(v)
            router.route("/").handler { c -> c.response().end("Hello Kotlin Vertx Integration!") }
            router.route("/index").handler { c -> c.response().html().end("Hello Kotlin Vertx Integration Page!") }
            return router
        }
    
        fun HttpServerResponse.html(): HttpServerResponse {
            return this.putHeader("content-type", "text/html")
        }
    
    }

*  启动应用后浏览器访问[http://localhost:8080/index.html][http_localhost_8080_index.html]出现以下页面

![blob.jpg][blob.jpg 1]

[http_localhost_8080]: http://localhost:8080
[blob.jpg]: /images/20220307/33264e35da824c38b7f80f3ad6dac6c4.png
[http_localhost_8080_index.html]: http://localhost:8080/index.html
[blob.jpg 1]: /images/20220307/3c3d72c2bf3343529937149dff44eeb9.png