rust: utils: Introduce S390ToolsMetaData

Introduce S390ToolsMetaData struct, it can be used to generate the
s390-tools specific JSON metadata.

Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Signed-off-by: Marc Hartmayer <marc@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>

rust/utils/Cargo.toml

@@ -5,8 +5,12 @@ edition.workspace = true
 license.workspace = true
 
 [dependencies]
+chrono = { version = "0.4.43", default-features = false, features = ["std"] }
 clap = { version ="4.5", features = ["derive", "wrap_help"] }
 libc = "0.2.169"
 log = { version = "0.4.25", features = ["std", "release_max_level_debug"] }
 pv = { path = "../pv", package = "s390_pv" }
 serde = { version = "1.0.217"}
+
+[dev-dependencies]
+serde_json = "1.0.149"

rust/utils/src/json.rs

@@ -0,0 +1,77 @@
+use std::time::{SystemTime, UNIX_EPOCH};
+
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+
+use crate::gethostname;
+
+#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub struct S390ToolsMetaData {
+    pub api_level: u32,
+    pub version: String,
+    pub host: String,
+    pub time_epoch: u64,
+    pub time: String,
+}
+
+impl S390ToolsMetaData {
+    /// Creates a new S390ToolsMetaData with current system information
+    ///
+    /// # Arguments
+    ///
+    /// * `api_level` - The API level version to use
+    pub fn new(api_level: u32) -> Self {
+        let host = gethostname().unwrap_or("unknown".to_owned());
+        let version = crate::release_string!().to_string();
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .expect("System time before UNIX epoch");
+        let time_epoch = now.as_secs();
+        let dt = DateTime::<Utc>::from(UNIX_EPOCH + now);
+        let time = dt.format("%F %T%z").to_string();
+
+        Self {
+            api_level,
+            version,
+            host,
+            time_epoch,
+            time,
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_metadata_creation() {
+        let metadata = S390ToolsMetaData::new(1);
+        assert_eq!(metadata.api_level, 1);
+        assert!(!metadata.version.is_empty());
+        assert!(!metadata.host.is_empty());
+        assert!(metadata.time_epoch > 0);
+        assert!(!metadata.time.is_empty());
+    }
+
+    #[test]
+    fn test_metadata_serialization_deserialization() {
+        let metadata = S390ToolsMetaData {
+            api_level: 1,
+            version: "DEBUG_BUILD".to_string(),
+            host: "testhost".to_string(),
+            time_epoch: 1770912807,
+            time: "2026-02-12 16:13:27+0000".to_string(),
+        };
+
+        let json = serde_json::to_string(&metadata).unwrap();
+        assert_eq!(
+            json,
+            r#"{"api_level":1,"version":"DEBUG_BUILD","host":"testhost","time_epoch":1770912807,"time":"2026-02-12 16:13:27+0000"}"#
+        );
+        let deserialized: S390ToolsMetaData = serde_json::from_str(&json).unwrap();
+
+        assert_eq!(metadata, deserialized);
+    }
+}

rust/utils/src/lib.rs

@@ -8,6 +8,7 @@ mod exit_code;
 mod file;
 mod hexslice;
 mod hostname;
+mod json;
 mod log;
 mod tmpfile;
 
@@ -22,6 +23,7 @@ pub use crate::{
     file::{AtomicFile, AtomicFileOperation},
     hexslice::HexSlice,
     hostname::gethostname,
+    json::S390ToolsMetaData,
     log::PvLogger,
     tmpfile::TemporaryDirectory,
 };