도도의 초록누리

This time, I will introduce partitioning and high availability cluster (HaProxy) in MariaDB.

There are several ways to sustain a large system.

It is about partitioning techniques and clusters.

I would like to introduce the principle that a large-capacity system is supported through several methods.

The figure below is for a load balancer that distributes large-capacity systems.

It was introduced for the project called table partitioning and high principles and structure of MariaDB HAProxy the availability of one of the cluster load balancer.

- Apache Tomcat 9 - 2020년 9월 기준 - 최신

- Maven 3.6 - 2020년 9월 기준 - 최신

- 각종 RESTEasy 4.5.3 - 2020년 9월 기준 - 최신 (pom 셋팅)......

<?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.restmaven</groupId>

  <artifactId>restWeb</artifactId>

  <version>0.0.1-SNAPSHOT</version>

  <packaging>war</packaging>

  <name>restWeb Maven Webapp</name>

  <!-- FIXME change it to the project's website -->

  <url>http://localhost</url>

  <properties>

    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

    <maven.compiler.source>1.7</maven.compiler.source>

    <maven.compiler.target>1.7</maven.compiler.target>

  </properties>

  <dependencies>

    <dependency>

      <groupId>junit</groupId>

      <artifactId>junit</artifactId>

      <version>4.11</version>

      <scope>test</scope>

    </dependency>

    <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->

<dependency>

    <groupId>javax.servlet</groupId>

    <artifactId>javax.servlet-api</artifactId>

    <version>4.0.1</version>

    <scope>provided</scope>

</dependency>

    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->

<dependency>

    <groupId>com.fasterxml.jackson.core</groupId>

    <artifactId>jackson-databind</artifactId>

    <version>2.11.2</version>

</dependency>

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->

<dependency>

    <groupId>com.fasterxml.jackson.core</groupId>

    <artifactId>jackson-core</artifactId>

    <version>2.11.2</version>

</dependency>

<!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->

<dependency>

    <groupId>com.fasterxml.jackson.core</groupId>

    <artifactId>jackson-annotations</artifactId>

    <version>2.11.2</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.jboss.resteasy/resteasy-core -->

<dependency>

    <groupId>org.jboss.resteasy</groupId>

    <artifactId>resteasy-core</artifactId>

    <version>4.5.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.jboss.resteasy/resteasy-jaxb-provider -->

<dependency>

    <groupId>org.jboss.resteasy</groupId>

    <artifactId>resteasy-jaxb-provider</artifactId>

    <version>4.5.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.jboss.resteasy/resteasy-jsapi -->

<dependency>

    <groupId>org.jboss.resteasy</groupId>

    <artifactId>resteasy-jsapi</artifactId>

    <version>4.5.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.jboss.resteasy/resteasy-jackson2-provider -->

<dependency>

    <groupId>org.jboss.resteasy</groupId>

    <artifactId>resteasy-jackson2-provider</artifactId>

    <version>4.5.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.jboss.resteasy/resteasy-multipart-provider -->

<dependency>

    <groupId>org.jboss.resteasy</groupId>

    <artifactId>resteasy-multipart-provider</artifactId>

    <version>4.5.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/commons-io/commons-io -->

<dependency>

    <groupId>commons-io</groupId>

    <artifactId>commons-io</artifactId>

    <version>2.8.0</version>

</dependency>

  </dependencies>

  <build>

    <finalName>restWeb</finalName>

    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->

      <plugins>

        <plugin>

          <artifactId>maven-clean-plugin</artifactId>

          <version>3.1.0</version>

        </plugin>

        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->

        <plugin>

          <artifactId>maven-resources-plugin</artifactId>

          <version>3.0.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-compiler-plugin</artifactId>

          <version>3.8.0</version>

        </plugin>

        <plugin>

          <artifactId>maven-surefire-plugin</artifactId>

          <version>2.22.1</version>

        </plugin>

        <plugin>

          <artifactId>maven-war-plugin</artifactId>

          <version>3.2.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-install-plugin</artifactId>

          <version>2.5.2</version>

        </plugin>

        <plugin>

          <artifactId>maven-deploy-plugin</artifactId>

          <version>2.8.2</version>

        </plugin>

      </plugins>

    </pluginManagement>

  </build>

</project>

<?xml version="1.0" encoding="UTF-8"?>

<web-app 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">

  <display-name>Archetype Created Web Application</display-name>

  <context-param>

  <param-name>resteasy.resources</param-name>

  <param-value>com.example.restweb.resources.MyResources</param-value>

  </context-param>

  <context-param>

  <param-name>resteasy.servlet.mapping.prefix</param-name>

  <param-value>/rest</param-value>

  </context-param>

  <listener>

  <listener-class>org.jboss.resteasy.plugins.server.servlet.ResteasyBootstrap</listener-class>

  </listener>

  <servlet>

  <servlet-name>Resteasy JSAPI</servlet-name>

<servlet-class>org.jboss.resteasy.jsapi.JSAPIServlet</servlet-class>

</servlet>

  <servlet-mapping>

  <servlet-name>Resteasy JSAPI</servlet-name>

  <url-pattern>/rest-js</url-pattern>

  </servlet-mapping>

  <servlet>

  <servlet-name>Resteasy</servlet-name>

  <servlet-class>org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>Resteasy</servlet-name>

  <url-pattern>/rest/*</url-pattern>

  </servlet-mapping>

  <servlet>

  <servlet-name>HomeServlet</servlet-name>

  <servlet-class>com.example.restweb.controller.HomeServlet</servlet-class>

  </servlet>

  <servlet-mapping>

  <servlet-name>HomeServlet</servlet-name>

  <url-pattern>/HomeServlet</url-pattern>

  </servlet-mapping>

</web-app>

package com.example.restweb.resources;

import com.example.restweb.model.FileInfo;

import javax.ws.rs.Consumes;

import javax.ws.rs.Encoded;

import javax.ws.rs.FormParam;

import javax.ws.rs.GET;

import javax.ws.rs.POST;

import javax.ws.rs.PUT;

import javax.ws.rs.Path;

import javax.ws.rs.PathParam;

import javax.ws.rs.Produces;

import javax.ws.rs.QueryParam;

import javax.ws.rs.core.Context;

import javax.ws.rs.core.MediaType;

import javax.ws.rs.core.Response;

import javax.ws.rs.core.UriInfo;

import org.jboss.resteasy.annotations.providers.multipart.MultipartForm;

@Path("/api")

public class MyResources

{

// Index

@GET

@Path("")

    @Produces("application/json")

public Response get()

{

StringBuffer buf = new StringBuffer();

buf.append("ok");

return Response.status(200).entity(buf).build();

}

    @GET

    @Path("users/{id}")

    @Produces("application/json")

    public Response getUserById(@PathParam("id") Integer id)

    {

        User user = new User();

        user.setId(id);

        user.setFirstName("Lokesh");

        user.setLastName("Gupta");

        return Response.status(200).entity(user).build();

    }

    @Path("foo/{param}-{other}")

@PUT

    @Produces("application/json")

public Response putFooParam(@PathParam("param") String param,

  @PathParam("other") String other)

{

StringBuffer buf = new StringBuffer();

buf.append("param").append("=").append(param).append(";");

buf.append("other").append("=").append(other).append(";");

return Response.status(200).entity(buf).build();

}

@Path("form")

@POST

    @Produces("application/json")

public String postForm(@FormParam("id") String a,

   @FormParam("passwd") String b){

return a +"/" +b;

}

@Path("lookup")

@GET

    @Produces("application/json")

public Response lookup(@QueryParam("id") String id,

@Context UriInfo uriInfo)

{

StringBuffer buf = new StringBuffer();

buf.append("param").append("=").append(id).append(";");

return Response.status(200).entity(buf).build();

}

    @POST

    @Path("/upload-file")

    @Consumes(MediaType.MULTIPART_FORM_DATA)

    public Response uploadFile(@MultipartForm FileInfo info) throws Exception {

    String fileName = info.getFileName();

    // RESTEasy는 한글 자체가 안됨.

    /*

    form.setFileName(filename);

    System.out.println("파일명1:" + form.getFileName());

        String fileName = form.getFileName() == null ? "Unknown" : form.getFileName() ;

        String completeFilePath = "c:/temp2/" + fileName;

        try

        {

            //Save the file

            File file = new File(completeFilePath);

            if (!file.exists()) 

            {

                file.createNewFile();

            }

            FileOutputStream fos = new FileOutputStream(file);

            fos.write(form.getFileData());

            fos.flush();

            fos.close();

        } 

        catch (IOException e)

        {

            e.printStackTrace();

        }

        //Build a response to return

        */

        return Response.status(200)

            .entity("uploadFile is called, Uploaded file name : " + fileName).build();

    }

}

실험1)

-> 문자셋 찾기 실험(UTF-8, Euc-kr, us-ascil, windows-1251, ISO-8851-9? 등)

    (반복문으로 해당 문자인지 찾는 작업을 하였음.)

(실패)

실험2)

-> <form 태그 accept- utf-8> 가능하도록 설정

(실패)

실험3)

-> new String (originalText.getBytes("ISO-8851-9), "UTF-8") 등 변환 작업

(실패)

.......

실험4)

-> public response 함수명(@Context ServletRequest req......)에 req.setCharacterEncoding 설정

(실패)

(다수의 방법을 적용하였음.)

* 결론: 수 차례 실험 결과로는 동작하지 않는다. (2020-09-20일 기준)

- 오라클 데이터베이스 자체가 전혀 안 된다는 이야기는 아니고, Dialect 등이 엄격하게 버전을 인식하는 것으로 추측해본다.
  (실험을 해보면 Oracle 11, Oracle 12로 시도했을 때는 될 수도 있다는 이야기를 하고 싶었다.)
- 물론 시간적인 여력이 된다면, 연재해보겠다. 

  (오라클 제거하고, 컴퓨터 포멧이나 VirtualBox 등 각종 방법으로 실험을 한다고 했을 때 시간이 소요되는 작업이다. 결코 쉽지않은 작업들이다.)

* IDE: Spring-tool-suite-4-4.7.2 Release(Eclipse)

     Jboss - hibernate만 설치

* POM:

      java-servlet

      hibernate-em(entity-manager)

      oracle-19g(ojdbc8)

* Database: 

      Oracle Databases 19g

* Web Server:

      Apache Tomcat 9

특이한 점: 초기 웹서버를 리셋하고, URL주소를 입력하여 DB에 접근하면 무한 반응으로 대기상태에 한참 있다가 hibernate 동작에서 

한참 대기 후에 결과가 나옴.

<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN"

                                         "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

 <session-factory name="">

  <property name="hibernate.connection.driver_class">oracle.jdbc.driver.OracleDriver</property>

  <property name="hibernate.connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>

  <property name="hibernate.connection.username">사용자계정</property>

  <property name="hibernate.connection.password">비밀번호</property>

  <property name="hibernate.dialect">org.hibernate.dialect.Oracle12cDialect</property>

  <property name="hibernate.show_sql">true</property>

  <property name="hibernate.use_sql_comments">true</property>

  <property name="hibernate.format_sql">true</property>

  <mapping class="com.hibernateMaven.web.model.EmpTable"/>

 </session-factory>

</hibernate-configuration>

실험하면서 동작하였으면, 좋은 글 하나 나왔을 탠데 아쉽다는 조금 생각이 든다.