allow not implementing the crd method - for #355

for people wishing to minise their dependencies, add a skip_crd kube attr.
kube-rs · Dec 24, 2020 · ecacff7 · ecacff7
1 parent 71d570d
commit ecacff7
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Showing 4 changed files with 61 additions and 26 deletions.
diff --git a/examples/Cargo.toml b/examples/Cargo.toml
@@ -32,6 +32,7 @@ either = "1.6.0"
 # Some configuration tweaking require reqwest atm
 reqwest = { version = "0.10.8", default-features = false, features = ["json", "gzip", "stream"] }
 schemars = "0.8.0"
+static_assertions = "1.1.0"
 
 [[example]]
 name = "configmapgen_controller"

diff --git a/examples/crd_derive.rs b/examples/crd_derive.rs
@@ -2,6 +2,7 @@ use k8s_openapi::Resource;
 use kube::CustomResource;
 use schemars::JsonSchema;
 use serde::{Deserialize, Serialize};
+#[macro_use] extern crate static_assertions;
 
 /// Our spec for Foo
 ///
@@ -137,6 +138,7 @@ fn verify_resource() {
     assert_eq!(Foo::GROUP, "clux.dev");
     assert_eq!(Foo::VERSION, "v1");
     assert_eq!(Foo::API_VERSION, "clux.dev/v1");
+    assert_impl_all!(Foo: k8s_openapi::Resource, k8s_openapi::Metadata, Default);
 }
 
 #[test]
@@ -151,3 +153,21 @@ spec:
   name: """#;
     assert_eq!(exp, ser);
 }
+
+/// CustomResource without ::crd generated (skip_crd)
+#[derive(CustomResource, Serialize, Deserialize, Debug, Clone)]
+#[kube(group = "clux.dev", version = "v1", kind = "Bar", namespaced)]
+#[kube(skip_crd)]
+pub struct MyBar {
+    bars: u32,
+}
+
+// Verify CustomResource derivable with skip_crd
+#[test]
+fn verify_bar_is_a_custom_resource() {
+    println!("Kind {}", Bar::KIND);
+    let bar = Bar::new("five", MyBar { bars: 5 });
+    println!("Spec: {:?}", bar.spec);
+    assert_impl_all!(Bar: k8s_openapi::Resource, k8s_openapi::Metadata);
+    // TODO: not asserting crd trait (if we make it a trait)
+}
diff --git a/kube-derive/src/custom_resource.rs b/kube-derive/src/custom_resource.rs
@@ -20,6 +20,7 @@ struct KubeAttrs {
     kind_struct: String,
     /// lowercase plural of kind (inferred if omitted)
     plural: Option<String>,
+    skip_crdgen: bool,
     namespaced: bool,
     apiextensions: String,
     derives: Vec<String>,
@@ -163,6 +164,9 @@ impl CustomDerive for CustomResource {
                         if path.is_ident("namespaced") {
                             ka.namespaced = true;
                             continue;
+                        } else if path.is_ident("skip_crd") {
+                            ka.skip_crdgen = true;
+                            continue;
                         } else {
                             &meta
                         }
@@ -216,6 +220,7 @@ impl CustomDerive for CustomResource {
             kind_struct,
             version,
             namespaced,
+            skip_crdgen,
             derives,
             status,
             plural,
@@ -264,7 +269,7 @@ impl CustomDerive for CustomResource {
 
         // Schema generation is always enabled for v1 because it's mandatory.
         // TODO Enable schema generation for v1beta1 if the spec derives `JsonSchema`.
-        let schema_gen_enabled = apiextensions == "v1";
+        let schema_gen_enabled = apiextensions == "v1" && !skip_crdgen;
         // We exclude fields `apiVersion`, `kind`, and `metadata` from our schema because
         // these are validated by the API server implicitly. Also, we can't generate the
         // schema for `metadata` (`ObjectMeta`) because it doesn't implement `JsonSchema`.
@@ -372,7 +377,9 @@ impl CustomDerive for CustomResource {
         let short_json = serde_json::to_string(&shortnames).unwrap();
         let crd_meta_name = format!("{}.{}", plural, group);
         let crd_meta = quote! { { "name": #crd_meta_name } };
-        let jsondata = if apiextensions == "v1" {
+        let jsondata = if skip_crdgen {
+            quote! {}
+        } else if apiextensions == "v1" {
             quote! {
                 // Don't use definitions and don't include `$schema` because these are not allowed.
                 let gen = schemars::gen::SchemaSettings::openapi3().with(|s| {
@@ -432,32 +439,36 @@ impl CustomDerive for CustomResource {
         };
 
         // TODO: should ::crd be from a trait?
-        let impl_crd = quote! {
-            impl #rootident {
-                pub fn crd() -> #apiext::CustomResourceDefinition {
-                    let columns : Vec<#apiext::CustomResourceColumnDefinition> = serde_json::from_str(#printers).expect("valid printer column json");
-                    let scale: Option<#apiext::CustomResourceSubresourceScale> = if #scale_code.is_empty() {
-                        None
-                    } else {
-                        serde_json::from_str(#scale_code).expect("valid scale subresource json")
-                    };
-                    let shorts : Vec<String> = serde_json::from_str(#short_json).expect("valid shortnames");
-                    let subres = if #has_status {
-                        if let Some(s) = &scale {
-                            serde_json::json!({
-                                "status": {},
-                                "scale": scale
-                            })
+        let impl_crd = if skip_crdgen {
+            quote! {}
+        } else {
+            quote! {
+                impl #rootident {
+                    pub fn crd() -> #apiext::CustomResourceDefinition {
+                        let columns : Vec<#apiext::CustomResourceColumnDefinition> = serde_json::from_str(#printers).expect("valid printer column json");
+                        let scale: Option<#apiext::CustomResourceSubresourceScale> = if #scale_code.is_empty() {
+                            None
                         } else {
-                            serde_json::json!({"status": {} })
-                        }
-                    } else {
-                        serde_json::json!({})
-                    };
+                            serde_json::from_str(#scale_code).expect("valid scale subresource json")
+                        };
+                        let shorts : Vec<String> = serde_json::from_str(#short_json).expect("valid shortnames");
+                        let subres = if #has_status {
+                            if let Some(s) = &scale {
+                                serde_json::json!({
+                                    "status": {},
+                                    "scale": scale
+                                })
+                            } else {
+                                serde_json::json!({"status": {} })
+                            }
+                        } else {
+                            serde_json::json!({})
+                        };
 
-                    #jsondata
-                    serde_json::from_value(jsondata)
-                        .expect("valid custom resource from #[kube(attrs..)]")
+                        #jsondata
+                        serde_json::from_value(jsondata)
+                            .expect("valid custom resource from #[kube(attrs..)]")
+                    }
                 }
             }
         };

diff --git a/kube-derive/src/lib.rs b/kube-derive/src/lib.rs
@@ -112,6 +112,9 @@ use custom_resource::CustomResource;
 ///
 /// **NOTE**: Support for `v1` requires deriving the openapi v3 `JsonSchema` via the `schemars` dependency.
 ///
+/// ### `#[kube(skip_crd)]`
+/// To indicate that the generated `::crd()` method is not required. Allow eliding the `schemars` dependency.
+///
 /// ### `#[kube(namespaced)]`
 /// To specify that this is a namespaced resource rather than cluster level.
 ///