build: only sign if a gpg key able to sign is present

src/build.rs

@@ -2,19 +2,59 @@ use std::error::Error;
 use std::path::Path;
 use std::process::Command;
 
+use crate::changelog::parse_changelog_footer;
+use crate::utils::gpg;
+
 /// Build a Debian source package (to a .dsc)
 pub fn build_source_package(cwd: Option<&Path>) -> Result<(), Box<dyn Error>> {
     let cwd = cwd.unwrap_or_else(|| Path::new("."));
 
+    // Parse changelog to get maintainer information from the last modification entry
+    let changelog_path = cwd.join("debian/changelog");
+    let (maintainer_name, maintainer_email) = parse_changelog_footer(&changelog_path)?;
+
+    // Check if a GPG key matching the maintainer's email exists
+    let signing_key = match gpg::find_signing_key_for_email(&maintainer_email) {
+        Ok(key) => key,
+        Err(e) => {
+            // If GPG is not available or there's an error, continue without signing
+            log::warn!("Failed to check for GPG key: {}", e);
+            None
+        }
+    };
+
+    // Build arguments
+    let mut args = vec!["-S", "-I", "-i", "-nc", "-d"];
+
+    // If a signing key is found, use it for signing
+    if let Some(key_id) = &signing_key {
+        args.push("-sa"); // Sign the source package
+        args.push("-k");
+        args.push(key_id);
+        log::info!("Using GPG key {} for signing", key_id);
+    } else {
+        log::info!(
+            "No GPG key found for {} ({}), building without signing",
+            maintainer_name,
+            maintainer_email
+        );
+    }
+
     let status = Command::new("dpkg-buildpackage")
         .current_dir(cwd)
-        .args(["-S", "-I", "-i", "-nc", "-d"])
+        .args(&args)
         .status()?;
 
     if !status.success() {
         return Err(format!("dpkg-buildpackage failed with status: {}", status).into());
     }
 
+    if signing_key.is_some() {
+        println!("Package built and signed successfully!");
+    } else {
+        println!("Package built successfully (unsigned).");
+    }
+
     Ok(())
 }