fix: use wildcard COPY for .git directory, use RAILWAY_GIT_COMMIT_SHA as fallback

Dockerfile

@@ -38,8 +38,10 @@ WORKDIR /usr/src/banner
 # Copy dependency files for better layer caching
 COPY ./Cargo.toml ./Cargo.lock* ./
 
-# Copy .git directory for build.rs to access Git information
-COPY ./.git ./.git
+# Copy .git directory for build.rs to access Git information (if available)
+# This will copy .git (and .gitignore) if it exists, but won't fail if it doesn't
+# While normally a COPY requires at least one file, .gitignore should still be available, so this wildcard should always work
+COPY ./.git* ./
 
 # Copy build.rs early so it can run during the first build
 COPY ./build.rs ./

build.rs

@@ -1,10 +1,11 @@
 use std::process::Command;
 
 fn main() {
-    // Get the current Git commit hash
+    // Try to get Git commit hash from Railway environment variable first
+    let git_hash = std::env::var("RAILWAY_GIT_COMMIT_SHA").unwrap_or_else(|_| {
+        // Fallback to git command if not on Railway
         let output = Command::new("git").args(["rev-parse", "HEAD"]).output();
-
-    let git_hash = match output {
+        match output {
             Ok(output) => {
                 if output.status.success() {
                     String::from_utf8_lossy(&output.stdout).trim().to_string()
@@ -13,7 +14,8 @@ fn main() {
                 }
             }
             Err(_) => "unknown".to_string(),
-    };
+        }
+    });
 
     // Get the short hash (first 7 characters)
     let short_hash = if git_hash != "unknown" && git_hash.len() >= 7 {
@@ -26,7 +28,9 @@ fn main() {
     println!("cargo:rustc-env=GIT_COMMIT_HASH={}", git_hash);
     println!("cargo:rustc-env=GIT_COMMIT_SHORT={}", short_hash);
 
-    // Rebuild if the Git commit changes
+    // Rebuild if the Git commit changes (only works when .git directory is available)
+    if std::path::Path::new(".git/HEAD").exists() {
         println!("cargo:rerun-if-changed=.git/HEAD");
         println!("cargo:rerun-if-changed=.git/refs/heads");
+    }
 }