frontend: examples: pdf_check example

Signed-off-by: Ralf Zerres <ralf.zerres@networkx.de>

frontend/examples/pdf_check.rs

@@ -0,0 +1,37 @@
+extern crate pdf_extract;
+extern crate lopdf;
+
+use std::env;
+use std::path::PathBuf;
+use std::path;
+use std::io::BufWriter;
+use std::fs::File;
+use pdf_extract::*;
+use lopdf::*;
+
+fn main() {
+    //let output_kind = "html";
+    //let output_kind = "txt";
+    //let output_kind = "svg";
+    let file = env::args().nth(1).unwrap();
+    let output_kind = env::args().nth(2).unwrap_or_else(|| "txt".to_owned());
+    println!("{}", file);
+    let path = path::Path::new(&file);
+    let filename = path.file_name().expect("expected a filename");
+    let mut output_file = PathBuf::new();
+    output_file.push(filename);
+    output_file.set_extension(&output_kind);
+    let mut output_file = BufWriter::new(File::create(output_file).expect("could not create output"));
+    let doc = Document::load(path).unwrap();
+
+    print_metadata(&doc);
+
+    let mut output: Box<dyn OutputDev> = match output_kind.as_ref() {
+	"txt" => Box::new(PlainTextOutput::new(&mut output_file as &mut dyn std::io::Write)),
+	"html" => Box::new(HTMLOutput::new(&mut output_file)),
+	"svg" => Box::new(SVGOutput::new(&mut output_file)),
+	_ => panic!(),
+    };
+
+    output_doc(&doc, output.as_mut());
+}