From b4ff749bc54dfe71cb26a1582468c9181bf33f6d Mon Sep 17 00:00:00 2001
From: Andrew Xie <dev@xie.is>
Date: Mon, 9 Feb 2026 14:43:10 -0500
Subject: [PATCH 1/2] fix: Prevent empty namespace creation

---
 ice/src/main/java/com/altinity/ice/cli/Main.java | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/ice/src/main/java/com/altinity/ice/cli/Main.java b/ice/src/main/java/com/altinity/ice/cli/Main.java
index 014d2ec..ddf8094 100644
--- a/ice/src/main/java/com/altinity/ice/cli/Main.java
+++ b/ice/src/main/java/com/altinity/ice/cli/Main.java
@@ -628,7 +628,15 @@ void createNamespace(
           boolean createNamespaceIfNotExists)
       throws IOException {
     try (RESTCatalog catalog = loadCatalog()) {
-      CreateNamespace.run(catalog, Namespace.of(name.split("[.]")), createNamespaceIfNotExists);
+      String[] split = name.split("[.]");
+      for (String level : split) {
+        if (level.isEmpty()) {
+          throw new IllegalArgumentException(
+              "Invalid namespace name: '.' cannot separate empty names");
+        }
+      }
+
+      CreateNamespace.run(catalog, Namespace.of(split), createNamespaceIfNotExists);
     }
   }
 

From 7cf131ccba478939845dd95b4353f3f26b36f54a Mon Sep 17 00:00:00 2001
From: Andrew Xie <dev@xie.is>
Date: Fri, 13 Feb 2026 16:53:17 -0500
Subject: [PATCH 2/2] Add scenario test for empty namespace

---
 .../scenarios/empty-namespace/run.sh.tmpl     | 23 +++++++++++++++++++
 .../scenarios/empty-namespace/scenario.yaml   |  6 +++++
 .../main/java/com/altinity/ice/cli/Main.java  |  3 +++
 3 files changed, 32 insertions(+)
 create mode 100644 ice-rest-catalog/src/test/resources/scenarios/empty-namespace/run.sh.tmpl
 create mode 100644 ice-rest-catalog/src/test/resources/scenarios/empty-namespace/scenario.yaml

diff --git a/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/run.sh.tmpl b/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/run.sh.tmpl
new file mode 100644
index 0000000..e37d93d
--- /dev/null
+++ b/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/run.sh.tmpl
@@ -0,0 +1,23 @@
+#!/bin/bash
+set -e
+
+echo "Running empty namespace test..."
+
+for namespace in $INVALID_NAMESPACES; do
+  if ! {{ICE_CLI}} -c {{CLI_CONFIG}} create-namespace "$namespace"; then
+    echo "OK create-namespace failed as expected"
+  else
+    echo "FAIL create-namespace should have failed with invalid namespace: $namespace"
+    exit 1
+  fi
+done
+
+namespaces=$(curl {{CATALOG_URI}}/v1/namespaces)
+expected='{"namespaces":[],"next-page-token":null}'
+
+if [ "$namespaces" == "$expected" ]; then
+  echo "OK list of namespaces is empty"
+else
+  echo "FAIL list of namespaces is not empty: $namespaces"
+  exit 1
+fi
diff --git a/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/scenario.yaml b/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/scenario.yaml
new file mode 100644
index 0000000..13cdd6c
--- /dev/null
+++ b/ice-rest-catalog/src/test/resources/scenarios/empty-namespace/scenario.yaml
@@ -0,0 +1,6 @@
+name: "Empty Namespace Creation"
+description: "Ensures empty namespaces cannot be created"
+
+env:
+  # space-separate list of namespaces that should cause an error with create-namespace
+  INVALID_NAMESPACES: ".. .test .a. a..b"
\ No newline at end of file
diff --git a/ice/src/main/java/com/altinity/ice/cli/Main.java b/ice/src/main/java/com/altinity/ice/cli/Main.java
index ddf8094..a10e1da 100644
--- a/ice/src/main/java/com/altinity/ice/cli/Main.java
+++ b/ice/src/main/java/com/altinity/ice/cli/Main.java
@@ -635,6 +635,9 @@ void createNamespace(
               "Invalid namespace name: '.' cannot separate empty names");
         }
       }
+      if (split.length == 0) {
+        throw new IllegalArgumentException("Invalid namespace name: name cannot be empty");
+      }
 
       CreateNamespace.run(catalog, Namespace.of(split), createNamespaceIfNotExists);
     }