fix(cache): add @operation to flushAll and fix fragile test assertion

- Add @Operation/@ApiResponses to flushAll() documenting behavior change
  (permission reset + PushPublishing reload) and that provider param is
  ignored
- Change freeMemory assertion from > 0 to >= 0 to prevent flaky failures
  under CI memory pressure

Author: hassandotcms

dotCMS/src/main/java/com/dotcms/rest/api/v1/system/cache/CacheResource.java

@@ -341,12 +341,25 @@ public Response flushObject(@Context final HttpServletRequest request,
     }
 
     /**
-     * Deletes an objects for a provider (will clean all group and generates a new key)
+     * Flushes all caches across all providers, resets permission references,
+     * and reloads PushPublishing filters. The provider path parameter is ignored —
+     * all caches are flushed regardless.
+     *
      *  @param request   {@link HttpServletRequest}
      *  @param response  {@link HttpServletResponse}
-     *  @param provider {@link String}
+     *  @param provider {@link String} ignored — all providers are flushed
      * @return Response
      */
+    @Operation(
+            summary = "Flush all caches",
+            description = "Flushes all caches across all providers, resets permission references, "
+                    + "and reloads PushPublishing filters. The provider path parameter is ignored."
+    )
+    @ApiResponses(value = {
+            @ApiResponse(responseCode = "200", description = "All caches flushed successfully"),
+            @ApiResponse(responseCode = "401", description = "Unauthorized - authentication required"),
+            @ApiResponse(responseCode = "403", description = "Forbidden - requires maintenance portlet access")
+    })
     @NoCache
     @DELETE
     @Path("/provider/{provider: .*}/flush")

dotCMS/src/main/webapp/WEB-INF/openapi/openapi.yaml

@@ -4244,6 +4244,8 @@ paths:
       - Cache Management
   /v1/caches/provider/{provider}/flush:
     delete:
+      description: "Flushes all caches across all providers, resets permission references,\
+        \ and reloads PushPublishing filters. The provider path parameter is ignored."
       operationId: flushAll
       parameters:
       - in: path
@@ -4253,11 +4255,13 @@ paths:
           type: string
           pattern: .*
       responses:
-        default:
-          content:
-            application/javascript: {}
-            application/json: {}
-          description: default response
+        "200":
+          description: All caches flushed successfully
+        "401":
+          description: Unauthorized - authentication required
+        "403":
+          description: Forbidden - requires maintenance portlet access
+      summary: Flush all caches
       tags:
       - Cache Management
   /v1/caches/provider/{provider}/flush/{group}:

dotcms-integration/src/test/java/com/dotcms/rest/api/v1/system/cache/CacheResourceIntegrationTest.java

@@ -123,7 +123,7 @@ public void test_getCacheStats_returns_valid_memory() {
         assertTrue("maxMemory should be positive", memory.maxMemory() > 0);
         assertTrue("allocatedMemory should be positive", memory.allocatedMemory() > 0);
         assertTrue("usedMemory should be positive", memory.usedMemory() > 0);
-        assertTrue("freeMemory should be positive", memory.freeMemory() > 0);
+        assertTrue("freeMemory should be non-negative", memory.freeMemory() >= 0);
         assertEquals("freeMemory should equal maxMemory minus usedMemory",
                 memory.maxMemory() - memory.usedMemory(), memory.freeMemory());
     }