Discovery: Add ApiGroup::resources_by_stability

examples/kubectl.rs

@@ -64,7 +64,7 @@ fn resolve_api_resource(discovery: &Discovery, name: &str) -> Option<(ApiResourc
         .groups()
         .flat_map(|group| {
             group
-                .recommended_resources()
+                .resources_by_stability()
                 .into_iter()
                 .map(move |res| (group, res))
         })

kube-client/src/discovery/apigroup.rs

@@ -6,8 +6,7 @@ use kube_core::{
     gvk::{GroupVersion, GroupVersionKind, ParseGroupVersionError},
     Version,
 };
-use std::cmp::Reverse;
-
+use std::{cmp::Reverse, collections::HashMap, iter::Iterator};
 
 /// Describes one API groups collected resources and capabilities.
 ///
@@ -244,6 +243,46 @@ impl ApiGroup {
         self.versioned_resources(ver)
     }
 
+    ///  Returns all (including the lost in the lower group version) resources having the most stable version.
+    ///
+    /// ```no_run
+    /// use kube::{Client, api::{Api, DynamicObject}, discovery::{self, verbs}, ResourceExt};
+    /// #[tokio::main]
+    /// async fn main() -> Result<(), Box<dyn std::error::Error>> {
+    ///     let client = Client::try_default().await?;
+    ///     let apigroup = discovery::group(&client, "apiregistration.k8s.io").await?;
+    ///     for (ar, caps) in apigroup.resources_by_stability() {
+    ///         if !caps.supports_operation(verbs::LIST) {
+    ///             continue;
+    ///         }
+    ///         let api: Api<DynamicObject> = Api::all_with(client.clone(), &ar);
+    ///         for inst in api.list(&Default::default()).await? {
+    ///             println!("Found {}: {}", ar.kind, inst.name());
+    ///         }
+    ///     }
+    ///     Ok(())
+    /// }
+    /// ```
+    /// See an example in [examples/kubectl.rs](https://github.com/kube-rs/kube/blob/main/examples/kubectl.rs)
+    pub fn resources_by_stability(&self) -> Vec<(ApiResource, ApiCapabilities)> {
+        let mut lookup = HashMap::new();
+        self.data.iter().for_each(|gvd| {
+            gvd.resources.iter().for_each(|resource| {
+                lookup
+                    .entry(resource.0.kind.clone())
+                    .or_insert_with(Vec::new)
+                    .push(resource);
+            })
+        });
+        lookup
+            .into_iter()
+            .map(|(_, mut v)| {
+                v.sort_by_cached_key(|(ar, _)| Reverse(Version::parse(ar.version.as_str()).priority()));
+                v[0].to_owned()
+            })
+            .collect()
+    }
+
     /// Returns the recommended version of the `kind` in the recommended resources (if found)
     ///
     /// ```no_run

kube/src/lib.rs

@@ -247,11 +247,14 @@ mod test {
         let foos: Api<Foo> = Api::default_namespaced(client.clone());
         // Apply from generated struct
         {
-            let foo = Foo::new("baz", FooSpec {
-                name: "baz".into(),
-                info: Some("old baz".into()),
-                replicas: 1,
-            });
+            let foo = Foo::new(
+                "baz",
+                FooSpec {
+                    name: "baz".into(),
+                    info: Some("old baz".into()),
+                    replicas: 1,
+                },
+            );
             let o = foos.patch("baz", &ssapply, &Patch::Apply(&foo)).await?;
             assert_eq!(o.spec.name, "baz");
             let oref = o.object_ref(&());
@@ -431,6 +434,103 @@ mod test {
         Ok(())
     }
 
+    #[tokio::test]
+    #[ignore] // needs cluster (fetches api resources, and lists all)
+    #[cfg(all(feature = "derive"))]
+    async fn derived_resources_by_stability_discoverable() -> Result<(), Box<dyn std::error::Error>> {
+        use crate::{
+            discovery::{self, Discovery},
+            runtime::wait::{await_condition, conditions},
+        };
+        use kube_core::crd::merge_crds;
+
+        mod v1alpha1 {
+            use super::*;
+
+            #[derive(CustomResource, Deserialize, Serialize, Clone, Debug, JsonSchema)]
+            #[kube(
+                group = "kube.rs",
+                version = "v1alpha1",
+                kind = "TestLowVersionCr",
+                namespaced
+            )]
+            #[kube(crates(kube_core = "crate::core"))] // for dev-dep test structure
+            pub struct TestLowVersionCrSpec {}
+        }
+
+        mod v1 {
+            use super::*;
+
+            #[derive(CustomResource, Deserialize, Serialize, Clone, Debug, JsonSchema)]
+            #[kube(group = "kube.rs", version = "v1", kind = "TestCr", namespaced)]
+            #[kube(crates(kube_core = "crate::core"))] // for dev-dep test structure
+            pub struct TestCrSpec {}
+        }
+
+        mod v2alpha1 {
+            use super::*;
+
+            #[derive(CustomResource, Deserialize, Serialize, Clone, Debug, JsonSchema)]
+            #[kube(group = "kube.rs", version = "v2alpha1", kind = "TestCr", namespaced)]
+            #[kube(crates(kube_core = "crate::core"))] // for dev-dep test structure
+            pub struct TestCrSpec {}
+        }
+
+        async fn apply_crd(
+            client: Client,
+            name: &str,
+            crd: CustomResourceDefinition,
+        ) -> Result<(), Box<dyn std::error::Error>> {
+            let crds: Api<CustomResourceDefinition> = Api::all(client.clone());
+            let ssapply = PatchParams::apply("kube").force();
+            crds.patch(name, &ssapply, &Patch::Apply(&crd)).await?;
+            let establish = await_condition(crds.clone(), name, conditions::is_crd_established());
+            let _ = tokio::time::timeout(std::time::Duration::from_secs(10), establish).await?;
+            Ok(())
+        }
+
+        let client = Client::try_default().await?;
+        let test_lowversion_crd = v1alpha1::TestLowVersionCr::crd();
+        let testcrd_v1 = v1::TestCr::crd();
+        let testcrd_v2alpha1 = v2alpha1::TestCr::crd();
+        let all_crds = vec![testcrd_v1.clone(), testcrd_v2alpha1.clone()];
+
+        apply_crd(client.clone(), "testlowversioncrs.kube.rs", test_lowversion_crd).await?;
+        apply_crd(client.clone(), "testcrs.kube.rs", merge_crds(all_crds, "v1")?).await?;
+
+        // run (almost) full discovery
+        let discovery = Discovery::new(client.clone())
+            // skip something in discovery (clux.dev crd being mutated in other tests)
+            .exclude(&["rbac.authorization.k8s.io", "clux.dev"])
+            .run()
+            .await?;
+
+        // check our custom resource first by resolving within groups
+        assert!(discovery.has_group("kube.rs"), "missing group kube.rs");
+
+        let group = discovery::group(&client, "kube.rs").await?;
+        let resources = group.resources_by_stability();
+        assert!(
+            resources
+                .iter()
+                .any(|(ar, _)| ar.kind == "TestCr" && ar.version == "v1"),
+            "wrong stable version"
+        );
+        assert!(
+            resources
+                .iter()
+                .any(|(ar, _)| ar.kind == "TestLowVersionCr" && ar.version == "v1alpha1"),
+            "lost low version resource"
+        );
+
+        // cleanup
+        let crds: Api<CustomResourceDefinition> = Api::all(client.clone());
+        crds.delete("testcrs.kube.rs", &DeleteParams::default()).await?;
+        crds.delete("testlowversioncrs.kube.rs", &DeleteParams::default())
+            .await?;
+        Ok(())
+    }
+
     #[tokio::test]
     #[ignore] // needs cluster (will create await a pod)
     #[cfg(all(feature = "runtime"))]