make pydantic optional

news/+pydantic-optional.breaking.md

@@ -0,0 +1 @@
+`pip install reflex` no longer installs `pydantic`; pydantic model support activates when it is installed. Use the new `reflex[pydantic]` extra (or `reflex[db]`) to keep it.

packages/reflex-base/news/+pydantic-optional.breaking.md

@@ -0,0 +1 @@
+`pydantic` is no longer a hard dependency; pydantic model support activates when it is installed. Use the `reflex-base[pydantic]` extra (or `reflex[db]`) to keep it.

packages/reflex-base/pyproject.toml

@@ -9,12 +9,14 @@ maintainers = [{ name = "Khaleel Al-Adhami", email = "khaleel@reflex.dev" }]
 requires-python = ">=3.10"
 dependencies = [
     "packaging >=24.2,<27",
-    "pydantic >=2.12.0,<3.0",
     "rich >=13,<15",
     "typing_extensions >=4.13.0",
     "platformdirs >=4.3.7,<5.0",
 ]
 
+[project.optional-dependencies]
+pydantic = ["pydantic >=2.12.0,<3.0"]
+
 [tool.hatch.version]
 source = "uv-dynamic-versioning"
 

pyproject.toml

@@ -65,6 +65,7 @@ db = [
   "pydantic >=2.12.0,<3.0",
   "sqlmodel >=0.0.24,<0.1",
 ]
+pydantic = ["reflex-base[pydantic]"]
 
 [project.urls]
 homepage = "https://reflex.dev"

tests/units/test_optional_pydantic.py

@@ -0,0 +1,73 @@
+"""Verify reflex imports and works when pydantic is not installed."""
+
+import subprocess
+import sys
+
+# Runs in a subprocess with pydantic (and the db extras that require it)
+# blocked, mirroring the "without db dependencies" CI job.
+_SCRIPT = """
+import sys
+
+BLOCKED = ("pydantic", "sqlmodel", "alembic", "sqlalchemy")
+
+
+class _Filter:
+    # Hide blocked packages from every finder so both ``import`` and
+    # ``find_spec`` see them as absent.
+    def __init__(self, inner):
+        self.inner = inner
+
+    def find_spec(self, name, path=None, target=None):
+        if name.partition(".")[0] in BLOCKED:
+            return None
+        finder = getattr(self.inner, "find_spec", None)
+        return finder(name, path, target) if finder is not None else None
+
+
+sys.meta_path = [_Filter(f) for f in sys.meta_path]
+
+# find_spec consults sys.modules before meta_path — purge anything a .pth or
+# startup hook may have imported eagerly.
+for mod in [m for m in sys.modules if m.partition(".")[0] in BLOCKED]:
+    del sys.modules[mod]
+
+from importlib.util import find_spec
+
+assert find_spec("pydantic") is None
+
+import datetime
+
+import reflex as rx
+from reflex_base.utils import serializers
+
+
+class S(rx.State):
+    val: rx.Field[str] = rx.field("hello")
+
+
+comp = rx.text(S.val)
+assert "val" in str(comp.render())
+
+assert serializers.serialize(datetime.datetime(2026, 1, 2, 3, 4, 5)) == "2026-01-02 03:04:05"
+assert not any(
+    getattr(cls, "__module__", "").startswith("pydantic")
+    for cls in serializers.SERIALIZERS
+)
+
+print("OK")
+"""
+
+
+def test_reflex_works_without_pydantic() -> None:
+    """Core import, state, component render, and serializers work without pydantic."""
+    result = subprocess.run(
+        [sys.executable, "-c", _SCRIPT],
+        capture_output=True,
+        text=True,
+        timeout=120,
+        check=False,
+    )
+    assert result.returncode == 0, (
+        f"reflex failed without pydantic:\nstdout: {result.stdout}\nstderr: {result.stderr}"
+    )
+    assert "OK" in result.stdout