refactor(bootstrap): replace PostConstruct validator with ApplicationContextInitializer

bootstrap/src/main/java/com/pablotj/restemailbridge/bootstrap/EnvironmentValidatorInitializer.java

@@ -0,0 +1,29 @@
+package com.pablotj.restemailbridge.bootstrap;
+
+import org.springframework.context.ApplicationContextInitializer;
+import org.springframework.context.ConfigurableApplicationContext;
+
+public class EnvironmentValidatorInitializer implements ApplicationContextInitializer<ConfigurableApplicationContext> {
+
+    @Override
+    public void initialize(ConfigurableApplicationContext ctx) {
+        String[] requiredProperties = {
+                "APP_ENCRYPTION_SECRET",
+                "APP_ALLOWED_ORIGINS",
+                "DB_NAME",
+                "DB_USER",
+                "DB_PASSWORD",
+                "DB_HOST",
+                "DB_PORT",
+                "GMAIL_OAUTH_CLIENT_ID",
+                "GMAIL_OAUTH_CLIENT_SECRET"
+        };
+
+        for (String prop : requiredProperties) {
+            String value = ctx.getEnvironment().getProperty(prop);
+            if (value == null || value.isEmpty()) {
+                throw new IllegalStateException("ERROR: Property '" + prop + "' is not defined or empty");
+            }
+        }
+    }
+}

bootstrap/src/main/java/com/pablotj/restemailbridge/bootstrap/RestEmailBridgeApplication.java

@@ -11,6 +11,8 @@ import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
 public class RestEmailBridgeApplication {
 
     public static void main(String[] args) {
-        SpringApplication.run(RestEmailBridgeApplication.class, args);
+        SpringApplication app = new SpringApplication(RestEmailBridgeApplication.class);
+        app.addInitializers(new EnvironmentValidatorInitializer());
+        app.run(args);
     }
 }

infrastructure/src/main/java/com/pablotj/restemailbridge/infrastructure/config/AppPropertiesValidator.java

@@ -1,55 +0,0 @@
-package com.pablotj.restemailbridge.infrastructure.config;
-
-import jakarta.annotation.PostConstruct;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-import org.springframework.beans.factory.annotation.Value;
-import org.springframework.stereotype.Component;
-
-@Component
-public class AppPropertiesValidator {
-
-    private static final Logger log = LoggerFactory.getLogger(AppPropertiesValidator.class);
-
-    @Value("${app.encryption.secret:}")
-    private String encryptionSecret;
-
-    @Value("${app.cors.allowed-origins:}")
-    private String allowedOrigins;
-
-    @Value("${spring.datasource.url:}")
-    private String datasourceUrl;
-
-    @Value("${spring.datasource.username:}")
-    private String datasourceUser;
-
-    @Value("${spring.datasource.password:}")
-    private String datasourcePassword;
-
-    @Value("${gmail.oauth2.clientId:}")
-    private String gmailClientId;
-
-    @Value("${gmail.oauth2.clientSecret:}")
-    private String gmailClientSecret;
-
-    @PostConstruct
-    public void validate() {
-        check("APP_ENCRYPTION_SECRET", encryptionSecret, false);
-        check("APP_ALLOWED_ORIGINS", allowedOrigins, true);
-        check("DB_URL", datasourceUrl, true);
-        check("DB_USER", datasourceUser, true);
-        check("DB_PASSWORD", datasourcePassword, false);
-        check("GMAIL_OAUTH_CLIENT_ID", gmailClientId, true);
-        check("GMAIL_OAUTH_CLIENT_SECRET", gmailClientSecret, false);
-    }
-
-    private void check(String name, String value, boolean logValue) {
-        if (value == null || value.isEmpty()) {
-            throw new IllegalStateException("ERROR: Property '" + name + "' is not defined or empty");
-        } else if (logValue) {
-            log.info("Property '{}' is defined with value: {}", name, value);
-        } else {
-            log.info("Property '{}' is defined", name);
-        }
-    }
-}