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

src/changelog.rs

@@ -114,7 +114,8 @@ fn increment_suffix(version: &str, suffix: &str) -> String {
     }
 }
 
-/// Parse a changelog file first entry header, to obtain (package, version, series)
+/// Parse a changelog file first entry header
+/// Returns (package, version, series) tuple from the last modification entry
 pub fn parse_changelog_header(
     path: &Path,
 ) -> Result<(String, String, String), Box<dyn std::error::Error>> {
@@ -135,6 +136,33 @@ pub fn parse_changelog_header(
     }
 }
 
+/// Parse a changelog file footer to extract maintainer information
+/// Returns (name, email) tuple from the last modification entry
+pub fn parse_changelog_footer(path: &Path) -> Result<(String, String), Box<dyn std::error::Error>> {
+    let mut file = File::open(path)?;
+    let mut content = String::new();
+    file.read_to_string(&mut content)?;
+
+    // Find the last maintainer line (format: -- Name <email>  Date)
+    let re = Regex::new(r"--\s*([^<]+?)\s*<([^>]+)>\s*")?;
+
+    if let Some(last_match) = re.captures_iter(&content).last() {
+        let name = last_match
+            .get(1)
+            .map_or("", |m| m.as_str())
+            .trim()
+            .to_string();
+        let email = last_match
+            .get(2)
+            .map_or("", |m| m.as_str())
+            .trim()
+            .to_string();
+        Ok((name, email))
+    } else {
+        Err(format!("No maintainer information found in {}", path.display()).into())
+    }
+}
+
 /*
 * Obtain all commit messages as a list since a tagged version in a git repository
 */