chore(ci): bring git hash and git branch on build

build.rs

@@ -13,9 +13,11 @@
 //! **Debug mode** (`cargo build`):
 //!   • Copies HTML files to `$OUT_DIR` for `include_str!()` only.
 
+use std::env;
 use std::fs;
 use std::io;
 use std::path::{Path, PathBuf};
+use std::process::Command;
 
 // ─── HTML files embedded via include_str!() in Rust source ───────────────────
 const HTML_INCLUDE: &[&str] = &[
@@ -39,6 +41,8 @@ fn main() {
     println!("cargo:rerun-if-changed=static");
     println!("cargo:rerun-if-changed=build.rs");
 
+    git_status();
+
     // ── Guard: Docker cacher stage has no static/ ────────────────────────────
     if !static_dir.exists() {
         for name in HTML_INCLUDE {
@@ -62,6 +66,64 @@ fn main() {
     }
 }
 
+// ═══════════════════════════════════════════════════════════════════════════════
+// Grab git values
+// Support Github,  is treated (need upgrade if move to gitlab CircleCI, ...)
+// ═══════════════════════════════════════════════════════════════════════════════
+fn git_status() {
+    // Rerun the build script when the commit or branch changes
+    println!("cargo:rerun-if-changed=.git/HEAD");
+    println!("cargo:rerun-if-changed=.git/refs/heads");
+
+    let git_hash = first_env(&["GITHUB_SHA", "CI_COMMIT_SHA", "CIRCLE_SHA1", "GIT_COMMIT"])
+        .or_else(|| git(&["rev-parse", "HEAD"]))
+        .unwrap_or_else(|| "unknown".into());
+
+    println!("cargo:rustc-env=GIT_HASH={git_hash}");
+
+    let git_branch = first_env(&[
+        "GITHUB_HEAD_REF",    // GitHub: PR source branch (empty on push)
+        "GITHUB_REF_NAME",    // GitHub: branch/tag on push
+        "CI_COMMIT_REF_NAME", // GitLab
+        "CIRCLE_BRANCH",      // CircleCI
+        "GIT_BRANCH",         // Jenkins
+    ])
+    .or_else(|| git(&["rev-parse", "--abbrev-ref", "HEAD"]))
+    .filter(|b| b != "HEAD") // detached HEAD is not a real branch name
+    .unwrap_or_else(|| "unknown".into());
+    println!("cargo:rustc-env=GIT_BRANCH={git_branch}");
+
+    // CI builds: rerun if the injected env changes
+    for k in [
+        "GITHUB_SHA",
+        "GITHUB_HEAD_REF",
+        "GITHUB_REF_NAME",
+        "CI_COMMIT_SHA",
+        "CI_COMMIT_REF_NAME",
+        "CIRCLE_SHA1",
+        "CIRCLE_BRANCH",
+        "GIT_COMMIT",
+        "GIT_BRANCH",
+    ] {
+        println!("cargo:rerun-if-env-changed={k}");
+    }
+
+    println!("cargo:warning=OxiCloud building with git hash: {git_hash} and branch: {git_branch}");
+}
+
+fn git(args: &[&str]) -> Option<String> {
+    let out = Command::new("git").args(args).output().ok()?;
+    out.status.success().then_some(())?;
+    let s = String::from_utf8(out.stdout).ok()?.trim().to_string();
+    (!s.is_empty()).then_some(s)
+}
+
+fn first_env(keys: &[&str]) -> Option<String> {
+    keys.iter()
+        .find_map(|k| env::var(k).ok())
+        .filter(|s| !s.is_empty())
+}
+
 // ═══════════════════════════════════════════════════════════════════════════════
 // Release pipeline
 // ═══════════════════════════════════════════════════════════════════════════════