0. はじめに
Spring Sessionお試し用Webアプリはこちらで公開しています。
1. 導入 〜 前回おさらい 〜
前回の記事で、Spring Session利用環境が整いました。
今回は、基本動作を実機確認します。
2. Spring Session お試し用Webアプリ起動
お試し用Webアプリをcodeダウンロード&buildして、
Dockerを導入したホスト上で実行します。
正常に起動すると以下。
アプリ起動
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.4.0)
INFO---[ main]c.e.s.session.db2.demo.DemoApplication [Starting DemoApplication using Java 15 on user.local with PID 1828 ([workspace dir]demo/target/classes started by [user name] in [git dir]/repository/demo)
INFO---[ main]c.e.s.session.db2.demo.DemoApplication [No active profile set, falling back to default profiles: default
INFO---[ main]o.s.b.w.embedded.tomcat.TomcatWebServer [Tomcat initialized with port(s): 8080 (http)
INFO---[ main]o.apache.catalina.core.StandardService [Starting service [Tomcat]
INFO---[ main]org.apache.catalina.core.StandardEngine [Starting Servlet engine: [Apache Tomcat/9.0.39]
INFO---[ main]o.a.c.c.C.[Tomcat].[localhost].[/] [Initializing Spring embedded WebApplicationContext
INFO---[ main]w.s.c.ServletWebServerApplicationContext[Root WebApplicationContext: initialization completed in 697 ms
INFO---[ main]com.zaxxer.hikari.HikariDataSource [HikariPool-1 - Starting...
INFO---[ main]com.zaxxer.hikari.HikariDataSource [HikariPool-1 - Start completed.
INFO---[ main]o.s.s.concurrent.ThreadPoolTaskExecutor [Initializing ExecutorService 'applicationTaskExecutor'
INFO---[ main]o.s.b.w.embedded.tomcat.TomcatWebServer [Tomcat started on port(s): 8080 (http) with context path ''
INFO---[ main]s.a.ScheduledAnnotationBeanPostProcessor[No TaskScheduler/ScheduledExecutorService bean found for scheduled processing
INFO---[ main]c.e.s.session.db2.demo.DemoApplication [Started DemoApplication in 1.643 seconds (JVM running for 7.199)
INFO---[nio-8080-exec-1]o.a.c.c.C.[Tomcat].[localhost].[/] [Initializing Spring DispatcherServlet 'dispatcherServlet'
INFO---[nio-8080-exec-1]o.s.web.servlet.DispatcherServlet [Initializing Servlet 'dispatcherServlet'
INFO---[nio-8080-exec-1]o.s.web.servlet.DispatcherServlet [Completed initialization in 1 ms
3. 確認:セッション永続化
まずはコンテナに入って、Db2側テーブルに何もデータ無いこと確認。
テーブル確認
[db2inst1@cb23f39d4164 ~]$ db2 "select * from db2inst1.SPRING_SESSION;"
PRIMARY_ID SESSION_ID CREATION_TIME LAST_ACCESS_TIME MAX_INACTIVE_INTERVAL EXPIRY_TIME PRINCIPAL_NAME
------------------------------------ ------------------------------------ -------------------- -------------------- --------------------- -------------------- ----------------------------------------------------------------------------------------------------
0 record(s) selected.
続いて下記URLに、Webブラウザでアクセス。
http://localhost:8080/sessionDemo
Webアプリの標準出力に、以下が出力されていれば正常稼働です。
標準出力
HttpSession.setAttribute Called. Count:1
Webブラウザ側は以下。
お試し用Webアプリ、該当Controllerはこちら。
挙動は以下です。
- Controller内のstaticなcounter変数を使い、HttpSessionにkey-valueを保持。
HttpSessionUsingController.java
private static int setAttr_count = 0;
- /sessionDemoにリクエスト有る毎にcounterを1加算。
- 裏側でSpring Sessionが働く。既にデータ有れば、セッション復元。
- 処理が完了し次第、Db2テーブルにセッション永続化。
HttpSessionUsingController.java
@GetMapping("/sessionDemo")
public static String sessionDemo(HttpServletRequest req, HttpServletResponse resp) {
HttpSession hs = req.getSession();
hs.setAttribute("demoKey"+setAttr_count, "demoValue"+setAttr_count);
setAttr_count++;
String return_str = "HttpSession.setAttribute Called." + " Count:" + setAttr_count;
System.out.println(return_str);
return return_str;
}
想定どおりに動いていれば、Db2コンテナ側のテーブルには
先ほどのアクセスを契機に生成されたセッションが、永続化されている筈です。
確認してみましょう。
テーブル確認
[db2inst1@cb23f39d4164 ~]$ db2 "select * from db2inst1.SPRING_SESSION;"
PRIMARY_ID SESSION_ID CREATION_TIME LAST_ACCESS_TIME MAX_INACTIVE_INTERVAL EXPIRY_TIME PRINCIPAL_NAME
------------------------------------ ------------------------------------ -------------------- -------------------- --------------------- -------------------- ----------------------------------------------------------------------------------------------------
484dc780-e9d0-4d17-bc75-71a025944b1e 462fae51-012d-432f-b80e-f27413c85555 1607347460733 1607347460974 1800 1607349260974 -
1 record(s) selected.
[db2inst1@cb23f39d4164 ~]$
[db2inst1@cb23f39d4164 ~]$ db2 "select * from db2inst1.SPRING_SESSION_ATTRIBUTES;"
SESSION_PRIMARY_ID ATTRIBUTE_NAME ATTRIBUTE_BYTES
------------------------------------ -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
484dc780-e9d0-4d17-bc75-71a025944b1e demoKey0 x'ACED000574000A64656D6F56616C756530'
1 record(s) selected.
しっかり永続化されている、みたいですね。
4. 確認: セッション取得
データ永続化しても、使えなければ片手落ち。
永続化したセッションを取得できるか、確認しましょう。
下記URLにアクセスします。
http://localhost:8080/getAllInsertedValues
実装はこちら。
セッション情報に保持しているKeyおよび、対のValueが
Json形式で出力されます。
実装の観点では以下の通り
普段のWebアプリと変わらずに、HttpSession用いていることが特徴です。
HttpSessionUsingController.java
public static String getAllInsertedValue(HttpServletRequest req, HttpServletResponse resp) {
HttpSession hs = req.getSession();
// 割愛
}
5. 確認: セッション取得 with webアプリ再起動
「本当に"永続化した"セッション情報が使えているか？」
「実はオンメモリで動いてないか？」観点で、シナリオ追加です。
さきほど利用したブラウザは閉じずに、置いておきつつ
お試し用Webアプリを停止＆起動してみます。
（スクショ割愛）
その後、再度Webブラウザで、下記URLにアクセス。
http://localhost:8080/getAllInsertedValues
Webアプリ停止する直前と
全く同一のKeyおよびValueが、画面に表示されていれば成功です。
よしよし、大丈夫ですね。
6. 終わりに
第1回は、お試し用Webアプリの挙動をベースに
Spring Session基本動作を紹介させて頂きました。
今回は手動で、アプリ起動・停止しましたが
AWS Lambdaやkubernetesクラスタなど、クラウドネイティブに
稼働サーバが自動で休眠・再起・増台し得る環境において、有用な機能だと思います。
次回は、いつになるか不明ですが…
反響あれば、Spring Session発展編を扱う予定。乞うご期待です。