Allow AlwaysProp

.gitignore

@@ -160,7 +160,7 @@ cython_debug/
 #  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
 #  and can be added to the global gitignore or merged into this file.  For a more nuclear
 #  option (not recommended) you can uncomment the following to ignore the entire idea folder.
-#.idea/
+.idea/
 
 # because this is a package, we don't want to commit the lock file
 poetry.lock

inertia/__init__.py

@@ -1,6 +1,6 @@
 from .http import InertiaResponse, inertia, location, render
 from .share import share
-from .utils import defer, lazy, merge, optional
+from .utils import defer, lazy, merge, optional, always
 
 __all__ = [
     "InertiaResponse",
@@ -12,4 +12,5 @@
     "lazy",
     "merge",
     "optional",
+    "always"
 ]

inertia/http.py

@@ -8,7 +8,7 @@
 from django.template.loader import render_to_string
 
 from .helpers import deep_transform_callables, validate_type
-from .prop_classes import DeferredProp, IgnoreOnFirstLoadProp, MergeableProp
+from .prop_classes import DeferredProp, IgnoreOnFirstLoadProp, MergeableProp, AlwaysProp
 from .settings import settings
 
 INERTIA_REQUEST_ENCRYPT_HISTORY = "_inertia_encrypt_history"
@@ -92,14 +92,20 @@ def build_props(self):
             **(self.request.inertia),
             **self.props,
         }
+        delete_queue = set()
+
+        for key, value in _props.items():
+            if isinstance(value, AlwaysProp):
+                continue
 
-        for key in list(_props.keys()):
             if self.request.is_a_partial_render(self.component):
                 if key not in self.request.partial_keys():
-                    del _props[key]
+                    delete_queue.add(key)
             else:
                 if isinstance(_props[key], IgnoreOnFirstLoadProp):
-                    del _props[key]
+                    delete_queue.add(key)
+
+        _props = {key: val for key, val in _props.items() if key not in delete_queue}
 
         return deep_transform_callables(_props)
 

inertia/prop_classes.py

@@ -19,6 +19,10 @@ class IgnoreOnFirstLoadProp:
     pass
 
 
+class AlwaysProp(CallableProp):
+    pass
+
+
 class OptionalProp(CallableProp, IgnoreOnFirstLoadProp):
     pass
 

inertia/tests/test_rendering.py

@@ -259,3 +259,21 @@ def test_with_props(self):
             ),
         ):
             self.client.get("/props/")
+
+
+class AlwaysPropsTestCase(InertiaTestCase):
+    def test_always_props_are_included_by_default(self):
+        self.assertJSONResponse(
+            self.inertia.get("/always/"),
+            inertia_page("always", props={"name": "Brian", "sport": "Basketball"}),
+        )
+
+    def test_always_props_are_included_when_not_requested(self):
+        self.assertJSONResponse(
+            self.inertia.get(
+                "/always/",
+                HTTP_X_INERTIA_PARTIAL_DATA="grit",
+                HTTP_X_INERTIA_PARTIAL_COMPONENT="TestComponent",
+            ),
+            inertia_page("always", props={"sport": "Basketball", "grit": "intense"}),
+        )

inertia/tests/testapp/urls.py

@@ -23,4 +23,5 @@
     path("clear-history/", views.clear_history_test),
     path("clear-history-redirect/", views.clear_history_redirect_test),
     path("clear-history-type-error/", views.clear_history_type_error_test),
+    path("always/", views.always_test),
 ]

inertia/tests/testapp/views.py

@@ -2,7 +2,7 @@
 from django.shortcuts import redirect
 from django.utils.decorators import decorator_from_middleware
 
-from inertia import defer, inertia, lazy, location, merge, optional, render, share
+from inertia import defer, inertia, lazy, location, merge, optional, render, share, always
 from inertia.http import INERTIA_SESSION_CLEAR_HISTORY, clear_history, encrypt_history
 
 
@@ -152,3 +152,12 @@ def clear_history_redirect_test(request):
 def clear_history_type_error_test(request):
     request.session[INERTIA_SESSION_CLEAR_HISTORY] = "foo"
     return {}
+
+
+@inertia("TestComponent")
+def always_test(request):
+    return {
+        "name": "Brian",
+        "sport": always(lambda: "Basketball"),
+        "grit": optional(lambda: "intense"),
+    }

inertia/utils.py

@@ -5,7 +5,7 @@
 from django.db.models.query import QuerySet
 from django.forms.models import model_to_dict as base_model_to_dict
 
-from .prop_classes import DeferredProp, MergeProp, OptionalProp
+from .prop_classes import DeferredProp, MergeProp, OptionalProp, AlwaysProp
 
 
 def model_to_dict(model):
@@ -41,6 +41,10 @@ def lazy(prop):
     return optional(prop)
 
 
+def always(prop):
+    return AlwaysProp(prop)
+
+
 def optional(prop):
     return OptionalProp(prop)