From 90b89224d880eaa4e584b6e8ac1f590be5b190d5 Mon Sep 17 00:00:00 2001
From: Willem <wrolleman@nationtech.io>
Date: Mon, 17 Nov 2025 15:20:51 -0500
Subject: [PATCH] fix: added K8sName type for strict naming of Kubernetes
 resources

---
 harmony_types/src/k8s_name.rs | 96 +++++++++++++++++++++++++++++++++++
 harmony_types/src/lib.rs      |  1 +
 2 files changed, 97 insertions(+)
 create mode 100644 harmony_types/src/k8s_name.rs

diff --git a/harmony_types/src/k8s_name.rs b/harmony_types/src/k8s_name.rs
new file mode 100644
index 0000000..9cb92ae
--- /dev/null
+++ b/harmony_types/src/k8s_name.rs
@@ -0,0 +1,96 @@
+use std::str::FromStr;
+
+use serde::Serialize;
+
+#[derive(Debug, Clone, PartialEq, Eq, Hash, Serialize)]
+pub struct K8sName(pub String);
+
+impl K8sName {
+    #[cfg(test)]
+    pub fn dummy() -> Self {
+        K8sName("example".to_string())
+    }
+
+    fn is_valid(name: &str) -> bool {
+        if name.is_empty() || name.len() > 63 {
+            return false;
+        }
+
+        let b = name.as_bytes();
+
+        if !b[0].is_ascii_alphanumeric() || !b[b.len() - 1].is_ascii_alphanumeric() {
+            return false;
+        }
+
+        b.iter()
+            .all(|c| c.is_ascii_lowercase() || c.is_ascii_digit() || *c == b'-')
+    }
+}
+
+impl FromStr for K8sName {
+    type Err = K8sNameError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        if !Self::is_valid(s) {
+            return Err(K8sNameError::InvalidFormat(format!(
+                "Invalid Kubernetes resource name '{s}': \
+                     must match DNS-1123 (lowercase alphanumeric, hyphens, <=63 chars)"
+            )));
+        };
+
+        Ok(K8sName(s.to_string()))
+    }
+}
+
+#[derive(Debug)]
+pub enum K8sNameError {
+    InvalidFormat(String),
+}
+
+impl From<&K8sName> for String {
+    fn from(value: &K8sName) -> Self {
+        value.0.clone()
+    }
+}
+
+impl std::fmt::Display for K8sName {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(&self.0)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_valid_name() {
+        assert!(K8sName::from_str("k8s-name-test").is_ok());
+        assert!(K8sName::from_str("n").is_ok());
+        assert!(K8sName::from_str("node1").is_ok());
+        assert!(K8sName::from_str("my-app-v2").is_ok());
+        assert!(K8sName::from_str("service123").is_ok());
+        assert!(K8sName::from_str("abcdefghijklmnopqrstuvwxyz-1234567890").is_ok());
+    }
+
+    #[test]
+    fn test_invalid_name() {
+        assert!(K8sName::from_str("").is_err());
+        assert!(K8sName::from_str(".config").is_err());
+        assert!(K8sName::from_str("_hidden").is_err());
+        assert!(K8sName::from_str("UPPER-CASE").is_err());
+        assert!(K8sName::from_str("123-$$$").is_err());
+        assert!(K8sName::from_str("app!name").is_err());
+        assert!(K8sName::from_str("my..app").is_err());
+        assert!(K8sName::from_str("backend-").is_err());
+        assert!(K8sName::from_str("-frontend").is_err());
+        assert!(K8sName::from_str("InvalidName").is_err());
+        assert!(
+            K8sName::from_str("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa")
+                .is_err()
+        );
+        assert!(K8sName::from_str("k8s name").is_err());
+        assert!(K8sName::from_str("k8s_name").is_err());
+        assert!(K8sName::from_str("k8s@name").is_err());
+    }
+}
diff --git a/harmony_types/src/lib.rs b/harmony_types/src/lib.rs
index 098379a..d5c7db0 100644
--- a/harmony_types/src/lib.rs
+++ b/harmony_types/src/lib.rs
@@ -1,3 +1,4 @@
 pub mod id;
+pub mod k8s_name;
 pub mod net;
 pub mod switch;