Use Rust build metadata for system version

apps/aether-gateway/build.rs

@@ -0,0 +1,45 @@
+use std::env;
+use std::process::Command;
+
+fn main() {
+    println!("cargo:rerun-if-env-changed=AETHER_VERSION");
+    println!("cargo:rerun-if-env-changed=GITHUB_REF_NAME");
+    println!("cargo:rerun-if-changed=../../.git/HEAD");
+
+    let package_version = env::var("CARGO_PKG_VERSION").unwrap_or_else(|_| "unknown".to_string());
+    let version = env::var("AETHER_VERSION")
+        .ok()
+        .filter(|value| !value.trim().is_empty())
+        .or_else(|| {
+            env::var("GITHUB_REF_NAME")
+                .ok()
+                .filter(|value| value.trim().starts_with('v'))
+        })
+        .or_else(git_describe_version)
+        .map(|value| normalize_version(&value))
+        .filter(|value| !value.is_empty())
+        .unwrap_or(package_version);
+
+    println!("cargo:rustc-env=AETHER_BUILD_VERSION={version}");
+}
+
+fn git_describe_version() -> Option<String> {
+    let output = Command::new("git")
+        .args(["describe", "--tags", "--always", "--dirty"])
+        .output()
+        .ok()?;
+    if !output.status.success() {
+        return None;
+    }
+    let version = String::from_utf8(output.stdout).ok()?;
+    let version = version.trim();
+    if version.is_empty() {
+        None
+    } else {
+        Some(version.to_string())
+    }
+}
+
+fn normalize_version(value: &str) -> String {
+    value.trim().strip_prefix('v').unwrap_or(value.trim()).to_string()
+}