cli: include build commit in version output

Signed-off-by: Gabriel Bercaru <[email protected]>

Author: bercarug

build.rs

@@ -0,0 +1,24 @@
+use std::process::Command;
+
+fn main() {
+    // Get latest commit SHA.
+    let output = Command::new("git")
+        .arg("describe")
+        .arg("--always")
+        .arg("--dirty")
+        .output();
+
+    // Convert command output to latest commit SHA and set an environment
+    // variable ("COMMIT_ID", only available in the build context) to
+    // the aforementioned commit SHA.
+    let stdout;
+    let output_str: &str = match output {
+        Ok(output) => {
+            stdout = output.stdout;
+            std::str::from_utf8(&stdout).expect("Invalid UTF-8 string provided")
+        }
+        _ => "",
+    };
+
+    println!("cargo:rustc-env=COMMIT_ID={}", output_str.trim());
+}

src/main.rs

@@ -23,8 +23,20 @@ use nitro_cli::{build_enclaves, console_enclaves, create_app};
 
 /// *Nitro CLI* application entry point.
 fn main() {
+    // Custom version (possibly including build commit).
+    let commit_id = env!("COMMIT_ID");
+    let version_str: String = match commit_id.len() {
+        0 => env!("CARGO_PKG_VERSION").to_string(),
+        _ => format!(
+            "{} (build commit: {})",
+            env!("CARGO_PKG_VERSION"),
+            commit_id
+        ),
+    };
+
     // Command-line specification for the Nitro CLI.
-    let app = create_app!();
+    let mut app = create_app!();
+    app = app.version(&*version_str);
     let args = app.get_matches();
     let logger = logger::init_logger();
     let mut replies: Vec<UnixStream> = vec![];