fix: allow uppercase characters in domain names

crates/stackable-operator/CHANGELOG.md

@@ -9,6 +9,10 @@ All notable changes to this project will be documented in this file.
 - Update `kube` to `1.1.0` ([#1049]).
 - BREAKING: Return type for `ListenerOperatorVolumeSourceBuilder::new()` is no onger a `Result` ([#1058]).
 
+### Fixed
+
+- Allow uppercase characters in domain names ([#1064]).
+
 ### Removed
 
 - BREAKING: Removed `last_update_time` from CRD ClusterCondition status ([#1054]).
@@ -18,6 +22,7 @@ All notable changes to this project will be documented in this file.
 [#1054]: https://github.com/stackabletech/operator-rs/pull/1054
 [#1058]: https://github.com/stackabletech/operator-rs/pull/1058
 [#1060]: https://github.com/stackabletech/operator-rs/pull/1060
+[#1064]: https://github.com/stackabletech/operator-rs/pull/1064
 
 ## [0.93.2] - 2025-05-26
 

crates/stackable-operator/src/builder/pod/container.rs

@@ -441,6 +441,7 @@ mod tests {
             resources::ResourceRequirementsBuilder,
         },
         commons::resources::ResourceRequirementsType,
+        validation::RFC_1123_LABEL_FMT,
     };
 
     #[test]
@@ -603,11 +604,11 @@ mod tests {
         assert!(ContainerBuilder::new("name-with-hyphen").is_ok());
         assert_container_builder_err(
             ContainerBuilder::new("ends-with-hyphen-"),
-            "regex used for validation is \"[a-z0-9]([-a-z0-9]*[a-z0-9])?\"",
+            &format!(r#"regex used for validation is "{RFC_1123_LABEL_FMT}""#),
         );
         assert_container_builder_err(
             ContainerBuilder::new("-starts-with-hyphen"),
-            "regex used for validation is \"[a-z0-9]([-a-z0-9]*[a-z0-9])?\"",
+            &format!(r#"regex used for validation is "{RFC_1123_LABEL_FMT}""#),
         );
     }
 
@@ -621,7 +622,9 @@ mod tests {
         assert!(ContainerBuilder::new("name_name").is_err());
         assert_container_builder_err(
             ContainerBuilder::new("name_name"),
-            "(e.g. \"example-label\", or \"1-label-1\", regex used for validation is \"[a-z0-9]([-a-z0-9]*[a-z0-9])?\")",
+            &format!(
+                r#"(e.g. "example-label", or "1-label-1", regex used for validation is "{RFC_1123_LABEL_FMT}""#
+            ),
         );
     }
 

crates/stackable-operator/src/commons/networking.rs

@@ -6,7 +6,7 @@ use snafu::Snafu;
 
 use crate::validation;
 
-/// A validated domain name type conforming to RFC 1123, so e.g. not an IP addresses
+/// A validated domain name type conforming to RFC 1123, so e.g. not an IP address
 #[derive(
     Serialize, Deserialize, Clone, Debug, Eq, PartialEq, Hash, Ord, PartialOrd, JsonSchema,
 )]

crates/stackable-operator/src/validation.rs

@@ -17,22 +17,21 @@ use snafu::Snafu;
 
 /// Minimal length required by RFC 1123 is 63. Up to 255 allowed, unsupported by k8s.
 const RFC_1123_LABEL_MAX_LENGTH: usize = 63;
-// FIXME: According to https://www.rfc-editor.org/rfc/rfc1035#section-2.3.1 domain names must start with a letter
-// (and not a number).
-const RFC_1123_LABEL_FMT: &str = "[a-z0-9]([-a-z0-9]*[a-z0-9])?";
-const RFC_1123_LABEL_ERROR_MSG: &str = "a lowercase RFC 1123 label must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character";
+pub const RFC_1123_LABEL_FMT: &str = "[a-zA-Z0-9]([-a-zA-Z0-9]*[a-zA-Z0-9])?";
+const RFC_1123_LABEL_ERROR_MSG: &str = "a RFC 1123 label must consist of alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character";
 
 /// This is a subdomain's max length in DNS (RFC 1123)
 const RFC_1123_SUBDOMAIN_MAX_LENGTH: usize = 253;
 const RFC_1123_SUBDOMAIN_FMT: &str =
     concatcp!(RFC_1123_LABEL_FMT, "(\\.", RFC_1123_LABEL_FMT, ")*");
-const RFC_1123_SUBDOMAIN_ERROR_MSG: &str = "a lowercase RFC 1123 subdomain must consist of lower case alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character";
 
 const DOMAIN_MAX_LENGTH: usize = RFC_1123_SUBDOMAIN_MAX_LENGTH;
 /// Same as [`RFC_1123_SUBDOMAIN_FMT`], but allows a trailing dot
 const DOMAIN_FMT: &str = concatcp!(RFC_1123_SUBDOMAIN_FMT, "\\.?");
-const DOMAIN_ERROR_MSG: &str = "a domain must consist of lower case alphanumeric characters, '-' or '.', and must start with an alphanumeric character and end with an alphanumeric character or '.'";
+const DOMAIN_ERROR_MSG: &str = "a domain must consist of alphanumeric characters, '-' or '.', and must start with an alphanumeric character and end with an alphanumeric character or '.'";
 
+// FIXME: According to https://www.rfc-editor.org/rfc/rfc1035#section-2.3.1 domain names must start with a letter
+// (and not a number).
 const RFC_1035_LABEL_FMT: &str = "[a-z]([-a-z0-9]*[a-z0-9])?";
 const RFC_1035_LABEL_ERROR_MSG: &str = "a DNS-1035 label must consist of lower case alphanumeric characters or '-', start with an alphabetic character, and end with an alphanumeric character";
 
@@ -55,11 +54,6 @@ pub(crate) static DOMAIN_REGEX: LazyLock<Regex> = LazyLock::new(|| {
     Regex::new(&format!("^{DOMAIN_FMT}$")).expect("failed to compile domain regex")
 });
 
-pub(crate) static RFC_1123_SUBDOMAIN_REGEX: LazyLock<Regex> = LazyLock::new(|| {
-    Regex::new(&format!("^{RFC_1123_SUBDOMAIN_FMT}$"))
-        .expect("failed to compile RFC 1123 subdomain regex")
-});
-
 static RFC_1123_LABEL_REGEX: LazyLock<Regex> = LazyLock::new(|| {
     Regex::new(&format!("^{RFC_1123_LABEL_FMT}$")).expect("failed to compile RFC 1123 label regex")
 });
@@ -204,19 +198,6 @@ pub fn is_domain(value: &str) -> Result {
     ])
 }
 
-/// Tests for a string that conforms to the definition of a subdomain in DNS (RFC 1123).
-pub fn is_rfc_1123_subdomain(value: &str) -> Result {
-    validate_all([
-        validate_str_length(value, RFC_1123_SUBDOMAIN_MAX_LENGTH),
-        validate_str_regex(
-            value,
-            &RFC_1123_SUBDOMAIN_REGEX,
-            RFC_1123_SUBDOMAIN_ERROR_MSG,
-            &["example.com"],
-        ),
-    ])
-}
-
 /// Tests for a string that conforms to the definition of a label in DNS (RFC 1123).
 /// Maximum label length supported by k8s is 63 characters (minimum required).
 pub fn is_rfc_1123_label(value: &str) -> Result {
@@ -267,22 +248,6 @@ fn mask_trailing_dash(mut name: String) -> String {
     name
 }
 
-/// name_is_dns_subdomain checks whether the passed in name is a valid
-/// DNS subdomain name
-///
-/// # Arguments
-///
-/// * `name` - is the name to check for validity
-/// * `prefix` - indicates whether `name` is just a prefix (ending in a dash, which would otherwise not be legal at the end)
-pub fn name_is_dns_subdomain(name: &str, prefix: bool) -> Result {
-    let mut name = name.to_string();
-    if prefix {
-        name = mask_trailing_dash(name);
-    }
-
-    is_rfc_1123_subdomain(&name)
-}
-
 /// name_is_dns_label checks whether the passed in name is a valid DNS label
 /// according to RFC 1035.
 ///
@@ -312,14 +277,28 @@ mod tests {
 
     use super::*;
 
+    const RFC_1123_SUBDOMAIN_ERROR_MSG: &str = "a RFC 1123 subdomain must consist of alphanumeric characters, '-' or '.', and must start and end with an alphanumeric character";
+
+    static RFC_1123_SUBDOMAIN_REGEX: LazyLock<Regex> = LazyLock::new(|| {
+        Regex::new(&format!("^{RFC_1123_SUBDOMAIN_FMT}$"))
+            .expect("failed to compile RFC 1123 subdomain regex")
+    });
+
+    /// Tests for a string that conforms to the definition of a subdomain in DNS (RFC 1123).
+    fn is_rfc_1123_subdomain(value: &str) -> Result {
+        validate_all([
+            validate_str_length(value, RFC_1123_SUBDOMAIN_MAX_LENGTH),
+            validate_str_regex(
+                value,
+                &RFC_1123_SUBDOMAIN_REGEX,
+                RFC_1123_SUBDOMAIN_ERROR_MSG,
+                &["example.com"],
+            ),
+        ])
+    }
+
     #[rstest]
     #[case("")]
-    #[case("A")]
-    #[case("ABC")]
-    #[case("aBc")]
-    #[case("A1")]
-    #[case("A-1")]
-    #[case("1-A")]
     #[case("-")]
     #[case("a-")]
     #[case("-a")]
@@ -346,24 +325,6 @@ mod tests {
     #[case("1 ")]
     #[case(" 1")]
     #[case("1 2")]
-    #[case("A.a")]
-    #[case("aB.a")]
-    #[case("ab.A")]
-    #[case("A1.a")]
-    #[case("a1.A")]
-    #[case("A.1")]
-    #[case("aB.1")]
-    #[case("A1.1")]
-    #[case("1A.1")]
-    #[case("0.A")]
-    #[case("01.A")]
-    #[case("012.A")]
-    #[case("1A.a")]
-    #[case("1a.A")]
-    #[case("A.B.C.D.E")]
-    #[case("AA.BB.CC.DD.EE")]
-    #[case("a.B.c.d.e")]
-    #[case("aa.bB.cc.dd.ee")]
     #[case("a@b")]
     #[case("a,b")]
     #[case("a_b")]
@@ -379,43 +340,67 @@ mod tests {
 
     #[rstest]
     #[case("a")]
+    #[case("A")]
     #[case("ab")]
     #[case("abc")]
+    #[case("aBc")]
+    #[case("ABC")]
     #[case("a1")]
+    #[case("A1")]
     #[case("a-1")]
+    #[case("A-1")]
     #[case("a--1--2--b")]
     #[case("0")]
     #[case("01")]
     #[case("012")]
     #[case("1a")]
     #[case("1-a")]
+    #[case("1-A")]
     #[case("1--a--b--2")]
     #[case("a.a")]
+    #[case("A.a")]
     #[case("ab.a")]
+    #[case("aB.a")]
+    #[case("ab.A")]
     #[case("abc.a")]
     #[case("a1.a")]
+    #[case("A1.a")]
+    #[case("a1.A")]
     #[case("a-1.a")]
     #[case("a--1--2--b.a")]
     #[case("a.1")]
+    #[case("A.1")]
     #[case("ab.1")]
+    #[case("aB.1")]
     #[case("abc.1")]
     #[case("a1.1")]
+    #[case("A1.1")]
     #[case("a-1.1")]
     #[case("a--1--2--b.1")]
     #[case("0.a")]
+    #[case("0.A")]
     #[case("01.a")]
+    #[case("01.A")]
     #[case("012.a")]
+    #[case("012.A")]
     #[case("1a.a")]
+    #[case("1A.a")]
+    #[case("1a.A")]
     #[case("1-a.a")]
     #[case("1--a--b--2")]
     #[case("0.1")]
     #[case("01.1")]
     #[case("012.1")]
     #[case("1a.1")]
+    #[case("1A.1")]
     #[case("1-a.1")]
     #[case("1--a--b--2.1")]
     #[case("a.b.c.d.e")]
+    #[case("a.B.c.d.e")]
+    #[case("A.B.C.D.E")]
     #[case("aa.bb.cc.dd.ee")]
+    #[case("aa.bB.cc.dd.ee")]
+    #[case("AA.BB.CC.DD.EE")]
     #[case("1.2.3.4.5")]
     #[case("11.22.33.44.55")]
     #[case(&"a".repeat(253))]
@@ -427,7 +412,9 @@ mod tests {
 
     #[rstest]
     #[case("cluster.local")]
+    #[case("CLUSTER.LOCAL")]
     #[case("cluster.local.")]
+    #[case("CLUSTER.LOCAL.")]
     fn is_domain_pass(#[case] value: &str) {
         assert!(is_domain(value).is_ok());
     }