Fix schemas containing both properties and additionalProperties due t…

…o serde(flatten)

See also: #844

Signed-off-by: Julius Michaelis <gitter@liftm.de>

kube-core/src/schema.rs

@@ -14,6 +14,10 @@ use schemars::{
 
 /// schemars [`Visitor`] that rewrites a [`Schema`] to conform to Kubernetes' "structural schema" rules
 ///
+/// The following two transformations are applied
+///  * Rewrite enums from `oneOf` to `object`s with multiple variants ([schemars#84](https://github.com/GREsau/schemars/issues/84))
+///  * Rewrite `additionalProperties` from `#[serde(flatten)]` to `x-kubernetes-preserve-unknown-fields` ([kube-rs#844](https://github.com/kube-rs/kube-rs/issues/844))
+///
 /// This is used automatically by `kube::derive`'s `#[derive(CustomResource)]`,
 /// but it can also be used manually with [`SchemaSettings::with_visitor`].
 ///
@@ -77,5 +81,15 @@ impl Visitor for StructuralSchemaRewriter {
                 }
             }
         }
+        if let Some(object) = &mut schema.object {
+            if !object.properties.is_empty() {
+                if object.additional_properties.as_deref() == Some(&Schema::Bool(true)) {
+                    object.additional_properties = None;
+                    schema
+                        .extensions
+                        .insert("x-kubernetes-preserve-unknown-fields".into(), true.into());
+                }
+            }
+        }
     }
 }

kube-derive/tests/crd_schema_test.rs

@@ -2,6 +2,7 @@ use chrono::{DateTime, NaiveDateTime, Utc};
 use kube_derive::CustomResource;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
+use std::collections::HashMap;
 
 // See `crd_derive_schema` example for how the schema generated from this struct affects defaulting and validation.
 #[derive(CustomResource, Serialize, Deserialize, Debug, PartialEq, Clone, JsonSchema)]
@@ -48,6 +49,14 @@ fn default_nullable() -> Option<String> {
     Some("default_nullable".into())
 }
 
+#[derive(CustomResource, Deserialize, Serialize, Clone, Debug, JsonSchema)]
+#[kube(group = "clux.dev", version = "v1", kind = "Flattening")]
+pub struct FlatteningSpec {
+    foo: String,
+    #[serde(flatten)]
+    arbitrary: HashMap<String, serde_json::Value>,
+}
+
 #[derive(Serialize, Deserialize, Debug, PartialEq, Clone, JsonSchema)]
 #[serde(rename_all = "camelCase")]
 enum ComplexEnum {
@@ -222,3 +231,18 @@ fn test_crd_schema_matches_expected() {
         .unwrap()
     );
 }
+
+#[test]
+fn flattening() {
+    use kube::core::CustomResourceExt;
+    let spec = &Flattening::crd().spec.versions[0]
+        .schema
+        .clone()
+        .unwrap()
+        .open_api_v3_schema
+        .unwrap()
+        .properties
+        .unwrap()["spec"];
+    assert_eq!(spec.x_kubernetes_preserve_unknown_fields, Some(true));
+    assert_eq!(spec.additional_properties, None);
+}