kopium

Kubernetes openapi unmangler.

Generates rust structs from customresourcedefinitions in your kubernetes cluster following the spec/status model, by using their embedded openapi schema.

⚠️ WARNING: not feature complete ⚠️

Requirements:

• stable customresourcedefinition with schema
• crd following standard spec/status model

Features

• Instantly queryable: generated type uses kube-derive to provide api integration with kube
• Rust doc comments: optionally extracted from description values in schema
• Safe case conversion: generated types uses rust standard camel_case with occasional serde rename attributes
• Usable locally and in CI: Can read crds by name in cluster via mycrd.group.io or from file via -f crd.yaml

Installation

Grab a prebuilt musl/darwin binary from the latest release, or install from crates.io:

sh cargo install kopium

Usage

If you have a crd installed in your cluster, pass a crd name accessible from your KUBECONFIG:

sh kopium prometheusrules.monitoring.coreos.com -A > prometheusrule.rs

Or pass a file/stdin via -f:

sh curl -sSL https://raw.githubusercontent.com/prometheus-operator/prometheus-operator/main/example/prometheus-operator-crd/monitoring.coreos.com_prometheusrules.yaml \ | kopium -Af - > prometheusrule.rs

Output

```rust use kube::CustomResource; use schemars::JsonSchema; use serde::{Serialize, Deserialize}; use std::collections::BTreeMap; use k8s_openapi::apimachinery::pkg::util::intstr::IntOrString;

/// Specification of desired alerting rule definitions for Prometheus.

[derive(CustomResource, Serialize, Deserialize, Clone, Debug, JsonSchema)]

[kube(group = "monitoring.coreos.com", version = "v1", kind = "PrometheusRule", plural = "prometheusrules")]

[kube(namespaced)]

pub struct PrometheusRuleSpec { /// Content of Prometheus rule file #[serde(default, skipserializingif = "Option::is_none")] pub groups: Option>, }

/// RuleGroup is a list of sequentially evaluated recording and alerting rules.

[derive(Serialize, Deserialize, Clone, Debug, JsonSchema)]

pub struct PrometheusRuleGroups { #[serde(default, skipserializingif = "Option::isnone")] pub interval: Option, pub name: String, #[serde(default, skipserializingif = "Option::isnone")] pub partialresponsestrategy: Option, pub rules: Vec, }

/// Rule describes an alerting or recording rule

[derive(Serialize, Deserialize, Clone, Debug, JsonSchema)]

pub struct PrometheusRuleGroupsRules { #[serde(default, skipserializingif = "Option::isnone")] pub alert: Option, #[serde(default, skipserializingif = "Option::isnone")] pub annotations: Option>, pub expr: IntOrString, #[serde(default, skipserializingif = "Option::isnone")] pub r#for: Option, #[serde(default, skipserializingif = "Option::isnone")] pub labels: Option>, #[serde(default, skipserializingif = "Option::is_none")] pub record: Option, } ```

Usage with kube

Simply add the generated file (e.g. output from above in prometheusrule.rs) to your library, and import (at least) the special root type:

```rust use prometheusrule::PrometheusRule; use kube::{Api, Client, ResourceExt};

[tokio::main]

async fn main() -> Result<(), Box> { let client = Client::trydefault().await?; let pr: Api = Api::defaultnamespaced(client); for p in pr.list(&Default::default()).await? { println!("Found PrometheusRule {} in current namespace", p.name()); } Ok(()) } ```

Autocomplete

Autocompletion for most shells available via kopium completions:

sh source <(kopium completions bash)

Testing

Unit tests and running kopium from a file do not require a cluster and can be run with:

sh cargo test --lib cargo run --bin kopium -- -f mycrd.yaml -A

Full integration tests use your current cluster to try to read a CRD and a gen object (instance of the CRD type) and parse it into the generated type:

sh cargo run --bin kopium -- -f prometheusrules.monitoring.coreos.com > tests/gen.rs echo "pub type CR = PrometheusRule;" >> tests/gen.rs kubectl apply -f tests/pr.yaml # needs to contain a CR with name "gen" cargo test --test runner -- --nocapture

test shortcuts available via just in the justfile and run pre-merge.

License

Apache 2.0 licensed. See LICENSE for details.