Stamp release builds from exported git metadata

build.rs

@@ -1,3 +1,4 @@
+use std::env;
 use std::process::Command;
 
 fn git(args: &[&str]) -> Option<String> {
@@ -12,14 +13,29 @@ fn git(args: &[&str]) -> Option<String> {
 fn main() {
     println!("cargo:rerun-if-changed=.git/HEAD");
     println!("cargo:rerun-if-changed=.git/index");
+    println!("cargo:rerun-if-env-changed=DOSH_BUILD_GIT_HASH");
+    println!("cargo:rerun-if-env-changed=DOSH_BUILD_COMMIT_DATE");
+    println!("cargo:rerun-if-env-changed=DOSH_BUILD_GIT_DIRTY");
 
-    let hash = git(&["rev-parse", "--short=12", "HEAD"]).unwrap_or_else(|| "unknown".into());
+    let hash = env::var("DOSH_BUILD_GIT_HASH")
-    let date = git(&["show", "-s", "--format=%cs", "HEAD"]).unwrap_or_else(|| "unknown".into());
+        .ok()
-    let dirty = Command::new("git")
+        .filter(|value| !value.is_empty())
+        .or_else(|| git(&["rev-parse", "--short=12", "HEAD"]))
+        .unwrap_or_else(|| "unknown".into());
+    let date = env::var("DOSH_BUILD_COMMIT_DATE")
+        .ok()
+        .filter(|value| !value.is_empty())
+        .or_else(|| git(&["show", "-s", "--format=%cs", "HEAD"]))
+        .unwrap_or_else(|| "unknown".into());
+    let dirty = match env::var("DOSH_BUILD_GIT_DIRTY").ok().as_deref() {
+        Some("1" | "true" | "yes" | "+dirty") => "+dirty",
+        Some(_) => "",
+        None => Command::new("git")
             .args(["diff", "--quiet", "--ignore-submodules", "--"])
             .status()
             .map(|status| if status.success() { "" } else { "+dirty" })
-        .unwrap_or("");
+            .unwrap_or(""),
+    };
 
     println!("cargo:rustc-env=DOSH_GIT_HASH={hash}{dirty}");
     println!("cargo:rustc-env=DOSH_COMMIT_DATE={date}");

scripts/package-release.sh

@@ -52,6 +52,22 @@ else
   release_dir="target/release"
 fi
 
+if command -v git >/dev/null 2>&1 && git rev-parse --is-inside-work-tree >/dev/null 2>&1; then
+  if [ -z "${DOSH_BUILD_GIT_HASH:-}" ]; then
+    export DOSH_BUILD_GIT_HASH="$(git rev-parse --short=12 HEAD)"
+  fi
+  if [ -z "${DOSH_BUILD_COMMIT_DATE:-}" ]; then
+    export DOSH_BUILD_COMMIT_DATE="$(git show -s --format=%cs HEAD)"
+  fi
+  if [ -z "${DOSH_BUILD_GIT_DIRTY+x}" ]; then
+    if git diff --quiet --ignore-submodules --; then
+      export DOSH_BUILD_GIT_DIRTY=0
+    else
+      export DOSH_BUILD_GIT_DIRTY=1
+    fi
+  fi
+fi
+
 if [ "$os" = "windows" ]; then
   if [ -n "$target" ]; then
     cargo build --release --target "$target" --bin dosh-client --bin dosh-bench

tests/release_scripts.rs

@@ -42,6 +42,23 @@ fn package_check_verifies_only_artifacts_it_builds() {
     );
 }
 
+#[test]
+fn package_release_stamps_git_build_info() {
+    let package = include_str!("../scripts/package-release.sh");
+    let build = include_str!("../build.rs");
+    for name in [
+        "DOSH_BUILD_GIT_HASH",
+        "DOSH_BUILD_COMMIT_DATE",
+        "DOSH_BUILD_GIT_DIRTY",
+    ] {
+        assert!(package.contains(name), "package script must export {name}");
+        assert!(build.contains(name), "build.rs must consume {name}");
+    }
+    assert!(package.contains("git rev-parse --short=12 HEAD"));
+    assert!(package.contains("git show -s --format=%cs HEAD"));
+    assert!(build.contains("cargo:rerun-if-env-changed=DOSH_BUILD_GIT_HASH"));
+}
+
 #[test]
 fn systemd_service_does_not_sandbox_remote_shells() {
     let service = include_str!("../packaging/systemd/dosh-server.service");