Better structure PDF renderer

src/output/mod.rs

@@ -1,10 +1,8 @@
-use wkhtmltopdf::PdfApplication;
+use config::Config;
 
+pub mod pdf;
 
-pub fn output(html: String) {
-    let mut pdf_app = PdfApplication::new().expect("Failed to init PDF application");
-    let mut pdfout = pdf_app.builder().build_from_html(&html).expect("failed to build pdf");
-
-    pdfout.save("foo.pdf").expect("failed to save foo.pdf");
-    println!("generated PDF saved as: foo.pdf");
+pub fn output(config: Config, output: String) -> Result<String, String> {
+    pdf::output(config, output);
+    return Ok("".into());
 }

src/output/pdf/mod.rs

@@ -0,0 +1,33 @@
+use config::Config;
+use utils::result_override;
+
+use std::error::Error;
+
+use wkhtmltopdf::{PdfApplication, Result as WKResult, PageSize};
+
+fn pdf_result<T>(res: WKResult<T>) -> Result<T, String> {
+    return match res {
+        Ok(out) => Ok(out),
+        Err(err) => Err(err.description().into()),
+    };
+}
+
+pub fn output(config: Config, html: String) -> Result<(), String> {
+    let output_location = &config.output["pdf"];
+    let mut pdf_app =
+        try!(result_override(PdfApplication::new(), "Failed to create PDF Application".into()));
+    let pdfout_result = pdf_app
+        .builder()
+        .page_size(PageSize::A4)
+        .image_quality(100)
+        .title(&config.title)
+        .build_from_html(&html);
+
+    let mut pdfout = try!(pdf_result(pdfout_result));
+    let output_file = try!(result_override(
+        pdfout.save(output_location),
+        format!("Failed to output PDF file to {}", output_location.display())
+    ));
+    debug_assert!(output_file.metadata().unwrap().is_file());
+    return Ok(());
+}

src/process.rs

@@ -8,6 +8,6 @@ pub fn build(config: Config) -> Result<(), String> {
     let input = try!(read_input_files(config.input.clone()));
     let raw_html = try!(build_input(config.clone(), input));
     println!("{}", raw_html);
-    output(raw_html);
+    try!(output(config, raw_html));
     return Ok(());
 }