{"id":19,"date":"2024-09-13T19:47:59","date_gmt":"2024-09-13T19:47:59","guid":{"rendered":"https:\/\/marcinzygmunt.pl\/blog\/?p=19"},"modified":"2025-09-24T18:44:41","modified_gmt":"2025-09-24T18:44:41","slug":"extending-simple-jwt-authentication-with-refresh-tokens-with-spring-boot-cache-version","status":"publish","type":"post","link":"https:\/\/marcinzygmunt.pl\/blog\/extending-simple-jwt-authentication-with-refresh-tokens-with-spring-boot-cache-version\/","title":{"rendered":"Extending Simple JWT Authentication with Refresh Tokens with Spring Boot (Cache version)\u00a0"},"content":{"rendered":"\n

<\/h1>\n\n\n\n

After building spring-boot-jwt-with-refresh<\/strong>, I wanted to demonstrate how to improve performance by caching refresh tokens<\/strong>. That\u2019s why I created spring-boot-jwt-with-refresh-cache<\/a><\/strong>. This project shows how to securely manage JWT authentication with refresh tokens stored in a cache, reducing database lookups and supporting scalable applications.<\/p>\n\n\n\n\n\n\n\n

TIP:<\/strong> Using a cache like Spring Cache improves performance. However, in multi-instance deployments, local caches are isolated per instance<\/strong>, which can lead to inconsistencies if a refresh token is used on a different server. This limitation is addressed in the Hazelcast version<\/strong>, where a shared cluster ensures all instances have access to the same refresh tokens.<\/p>\n\n\n\n

Like the previous examples, this project is built with Spring Boot 3<\/strong>.<\/p>\n\n\n\n

\"\"\n\t\t\t\n\t\t\t\t\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n\n\n\n
\n\n\n\n

What You Get<\/h3>\n\n\n\n
    \n
  • Basic Auth + JWT<\/strong>: Users log in with credentials and receive a JWT token.<\/li>\n\n\n\n
  • Refresh Tokens in Cache<\/strong>: Refresh tokens are stored in a cache, improving performance.<\/li>\n\n\n\n
  • Swagger UI<\/strong>: Explore and test endpoints at http:\/\/localhost:8088\/swagger-ui\/index.html<\/code>.<\/li>\n<\/ul>\n\n\n\n
    \n\n\n\n

    Setup in 4 Steps<\/h3>\n\n\n\n
      \n
    1. Clone the repository<\/strong><\/li>\n<\/ol>\n\n\n\n
      git clone https:\/\/github.com\/marcinzygmunt-pl\/spring-boot-jwt-with-refresh-cache.git\ncd spring-boot-jwt-with-refresh-cache<\/code><\/pre>\n\n\n\n
        \n
      1. Configure PostgreSQL and Cache<\/strong>
        Edit application.yml<\/code> with your database credentials and cache settings.<\/li>\n\n\n\n
      2. Run the application<\/strong><\/li>\n<\/ol>\n\n\n\n
        .\/mvnw spring-boot:run<\/code><\/pre>\n\n\n\n
          \n
        1. Test endpoints in Swagger UI<\/strong>
          Open http:\/\/localhost:8088\/swagger-ui\/index.html<\/code> and test login, token refresh, and protected endpoints.<\/li>\n<\/ol>\n\n\n\n
          \n\n\n\n
          Optional: Go Further<\/h3>\n\n\n\n
            \n
          • For multi-instance deployments<\/strong>, consider Hazelcast<\/strong> to share refresh tokens across all nodes reliably.<\/li>\n<\/ul>\n\n\n\n
            These options are explored in other branches for more advanced setups.<\/p>\n\n\n\n
            \n\n\n\n
            Final Note<\/h3>\n\n\n\n
            spring-boot-jwt-with-refresh-cache<\/strong> is the next step in the series: it builds on the refresh token mechanism<\/strong> and adds caching for efficiency<\/strong>. Be aware that local caches have limitations in multi-instance setups. The Hazelcast version<\/strong> resolves this issue by providing a shared cluster accessible by all instances, ensuring consistent token validation and refresh across the application.<\/p>\n","protected":false},"excerpt":{"rendered":"
            After building spring-boot-jwt-with-refresh, I wanted to demonstrate how to improve performance by caching refresh tokens. That\u2019s why I created spring-boot-jwt-with-refresh-cache. This project shows how to securely manage JWT\u2026<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_feature_clip_id":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_post_was_ever_published":false},"categories":[1],"tags":[9,5],"class_list":["post-19","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-jwt","tag-springboot"],"jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"","_links":{"self":[{"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/posts\/19","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/comments?post=19"}],"version-history":[{"count":7,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/posts\/19\/revisions"}],"predecessor-version":[{"id":155,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/posts\/19\/revisions\/155"}],"wp:attachment":[{"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/media?parent=19"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/categories?post=19"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/marcinzygmunt.pl\/blog\/wp-json\/wp\/v2\/tags?post=19"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}