src/main/java/net/siegeln/cameleer/saas/config/SecurityConfig.java

@@ -10,6 +10,7 @@ import org.springframework.security.config.annotation.web.configuration.EnableWe
 import org.springframework.security.config.http.SessionCreationPolicy;
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
 import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.security.oauth2.server.resource.web.authentication.BearerTokenAuthenticationFilter;
 import org.springframework.security.web.SecurityFilterChain;
 import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;
 
@@ -19,9 +20,11 @@ import org.springframework.security.web.authentication.UsernamePasswordAuthentic
 public class SecurityConfig {
 
     private final JwtAuthenticationFilter machineTokenFilter;
+    private final TenantResolutionFilter tenantResolutionFilter;
 
-    public SecurityConfig(JwtAuthenticationFilter machineTokenFilter) {
+    public SecurityConfig(JwtAuthenticationFilter machineTokenFilter, TenantResolutionFilter tenantResolutionFilter) {
         this.machineTokenFilter = machineTokenFilter;
+        this.tenantResolutionFilter = tenantResolutionFilter;
     }
 
     @Bean
@@ -50,7 +53,8 @@ public class SecurityConfig {
                         .anyRequest().authenticated()
                 )
                 .oauth2ResourceServer(oauth2 -> oauth2.jwt(jwt -> {}))
-                .addFilterBefore(machineTokenFilter, UsernamePasswordAuthenticationFilter.class);
+                .addFilterBefore(machineTokenFilter, UsernamePasswordAuthenticationFilter.class)
+                .addFilterAfter(tenantResolutionFilter, BearerTokenAuthenticationFilter.class);
 
         return http.build();
     }

src/main/java/net/siegeln/cameleer/saas/config/TenantContext.java

@@ -0,0 +1,22 @@
+package net.siegeln.cameleer.saas.config;
+
+import java.util.UUID;
+
+public final class TenantContext {
+
+    private static final ThreadLocal<UUID> CURRENT_TENANT = new ThreadLocal<>();
+
+    private TenantContext() {}
+
+    public static UUID getTenantId() {
+        return CURRENT_TENANT.get();
+    }
+
+    public static void setTenantId(UUID tenantId) {
+        CURRENT_TENANT.set(tenantId);
+    }
+
+    public static void clear() {
+        CURRENT_TENANT.remove();
+    }
+}

src/main/java/net/siegeln/cameleer/saas/config/TenantResolutionFilter.java

@@ -0,0 +1,47 @@
+package net.siegeln.cameleer.saas.config;
+
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import net.siegeln.cameleer.saas.tenant.TenantService;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.oauth2.jwt.Jwt;
+import org.springframework.security.oauth2.server.resource.authentication.JwtAuthenticationToken;
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import java.io.IOException;
+
+@Component
+public class TenantResolutionFilter extends OncePerRequestFilter {
+
+    private final TenantService tenantService;
+
+    public TenantResolutionFilter(TenantService tenantService) {
+        this.tenantService = tenantService;
+    }
+
+    @Override
+    protected void doFilterInternal(HttpServletRequest request,
+                                    HttpServletResponse response,
+                                    FilterChain filterChain) throws ServletException, IOException {
+        try {
+            var authentication = SecurityContextHolder.getContext().getAuthentication();
+
+            if (authentication instanceof JwtAuthenticationToken jwtAuth) {
+                Jwt jwt = jwtAuth.getToken();
+                String orgId = jwt.getClaimAsString("organization_id");
+
+                if (orgId != null) {
+                    tenantService.getByLogtoOrgId(orgId)
+                            .ifPresent(tenant -> TenantContext.setTenantId(tenant.getId()));
+                }
+            }
+
+            filterChain.doFilter(request, response);
+        } finally {
+            TenantContext.clear();
+        }
+    }
+}