imporved error handling

src/app/builder/asciidoctor.rs

@@ -0,0 +1,33 @@
+use std::process;
+
+use super::Builder;
+
+pub struct AsciiDoctorBuilder;
+
+impl Builder for AsciiDoctorBuilder {
+    fn build(&self, in_path: &str, out_path: &str) -> Result<(), String> {
+        let result = process::Command::new("asciidoctor")
+            .arg(format!("{in_path}"))
+            .arg(format!("--out-file={out_path}"))
+            .output();
+
+        if let Ok(success) = result {
+            if success.stderr.len() == 0 {
+                return Ok(());
+            } else {
+                return Err(AsciiDoctorBuilder::from_utf8(success.stderr));
+            }
+        } else {
+            return Err("command failed to execute".to_string());
+        }
+    }
+}
+
+impl AsciiDoctorBuilder {
+    fn from_utf8(input: Vec<u8>) -> String {
+        return match String::from_utf8(input) {
+            Ok(m) => m,
+            Err(e) => panic!("could not print error message: {}", e),
+        };
+    }
+}