feat: Add flux-converter

Cargo.toml

@@ -87,3 +87,7 @@ rsa.opt-level = 3
 [profile.dev.package]
 insta.opt-level = 3
 similar.opt-level = 3
+
+[patch.crates-io]
+# https://github.com/kube-rs/kube/pull/1759 will be in 1.1.0
+kube = { git = 'https://github.com/sbernauer/kube.git', branch = "fix/derive-conversion-types-0.99" }

crates/stackable-versioned-macros/Cargo.toml

@@ -25,8 +25,9 @@ normal = ["k8s-openapi", "kube"]
 proc-macro = true
 
 [features]
-full = ["k8s"]
+full = ["k8s", "flux-converter"]
 k8s = ["dep:kube", "dep:k8s-openapi"]
+flux-converter = ["k8s"]
 
 [dependencies]
 k8s-version = { path = "../k8s-version", features = ["darling"] }

crates/stackable-versioned-macros/src/codegen/container/mod.rs

@@ -84,28 +84,45 @@ impl Container {
         }
     }
 
-    /// Generates Kubernetes specific code to merge two or more CRDs into one.
+    /// Generates Kubernetes specific code to merge two CRDs or convert between different versions.
     ///
     /// This function only returns `Some` if it is a struct. Enums cannot be used to define
     /// Kubernetes custom resources.
-    pub(crate) fn generate_kubernetes_merge_crds(
+    pub(crate) fn generate_kubernetes_code(
         &self,
         enum_variant_idents: &[IdentString],
         enum_variant_strings: &[String],
         fn_calls: &[TokenStream],
         vis: &Visibility,
         is_nested: bool,
     ) -> Option<TokenStream> {
-        match self {
-            Container::Struct(s) => s.generate_kubernetes_merge_crds(
+        let Container::Struct(s) = self else {
+            return None;
+        };
+        let kubernetes_options = s.common.options.kubernetes_options.as_ref()?;
+
+        let mut tokens = TokenStream::new();
+
+        if !kubernetes_options.skip_merged_crd {
+            tokens.extend(s.generate_kubernetes_merge_crds(
                 enum_variant_idents,
                 enum_variant_strings,
                 fn_calls,
                 vis,
                 is_nested,
-            ),
-            Container::Enum(_) => None,
+            ));
         }
+
+        #[cfg(feature = "flux-converter")]
+        // TODO: Do we need a kubernetes_options.skip_conversion as well?
+        tokens.extend(super::flux_converter::generate_kubernetes_conversion(
+            &s.common.idents.kubernetes,
+            &s.common.idents.original,
+            enum_variant_idents,
+            enum_variant_strings,
+        ));
+
+        Some(tokens)
     }
 
     pub(crate) fn get_original_ident(&self) -> &Ident {
@@ -214,7 +231,7 @@ impl StandaloneContainer {
             });
         }
 
-        tokens.extend(self.container.generate_kubernetes_merge_crds(
+        tokens.extend(self.container.generate_kubernetes_code(
             &kubernetes_enum_variant_idents,
             &kubernetes_enum_variant_strings,
             &kubernetes_merge_crds_fn_calls,

crates/stackable-versioned-macros/src/codegen/container/struct.rs

@@ -349,6 +349,8 @@ impl Struct {
         vis: &Visibility,
         is_nested: bool,
     ) -> Option<TokenStream> {
+        assert_eq!(enum_variant_idents.len(), enum_variant_strings.len());
+
         match &self.common.options.kubernetes_options {
             Some(kubernetes_options) if !kubernetes_options.skip_merged_crd => {
                 let enum_ident = &self.common.idents.kubernetes;
@@ -377,12 +379,27 @@ impl Struct {
                         }
                     }
 
+                    #automatically_derived
+                    impl ::std::str::FromStr for #enum_ident {
+                        type Err = stackable_versioned::ParseResourceVersionError;
+
+                        fn from_str(version: &str) -> Result<Self, Self::Err> {
+                            match version {
+                                #(#enum_variant_strings => Ok(Self::#enum_variant_idents),)*
+                                _ => Err(stackable_versioned::ParseResourceVersionError::UnknownResourceVersion{version: version.to_string()}),
+                            }
+                        }
+                    }
+
                     #automatically_derived
                     impl #enum_ident {
                         /// Generates a merged CRD containing all versions and marking `stored_apiversion` as stored.
                         pub fn merged_crd(
                             stored_apiversion: Self
-                        ) -> ::std::result::Result<#k8s_openapi_path::apiextensions_apiserver::pkg::apis::apiextensions::v1::CustomResourceDefinition, #kube_core_path::crd::MergeError> {
+                        ) -> ::std::result::Result<
+                                #k8s_openapi_path::apiextensions_apiserver::pkg::apis::apiextensions::v1::CustomResourceDefinition,
+                                #kube_core_path::crd::MergeError
+                            > {
                             #kube_core_path::crd::merge_crds(vec![#(#fn_calls),*], &stored_apiversion.to_string())
                         }
                     }