First commit

native/xler_native/src/lib.rs

@@ -0,0 +1,76 @@
+#[macro_use] extern crate rustler;
+#[macro_use] extern crate rustler_codegen;
+#[macro_use] extern crate lazy_static;
+extern crate calamine;
+
+use rustler::{Env, NifResult, Encoder, Term};
+use calamine::{Reader, open_workbook_auto};
+use calamine::Error as CaError;
+
+mod atoms {
+    rustler_atoms! {
+        atom ok;
+        atom error;
+
+        // Posix
+        atom enoent; // File does not exist
+        atom eacces; // Permission denied
+        atom epipe;  // Broken pipe
+        atom eexist; // File exists
+    }
+}
+
+rustler_export_nifs! {
+    "Elixir.Xler.Native",
+    [("parse", 2, parse),
+    ("worksheets", 1, worksheets)],
+    None
+}
+
+fn io_error_to_term<'a>(env: Env<'a>, err: &CaError) -> Term<'a> {
+    let error = match err {
+        _ => format!("{}", err).encode(env),
+    };
+
+    (atoms::error(), error).encode(env)
+}
+
+fn worksheets<'a>(env: Env<'a>, args: &[Term<'a>]) -> NifResult<Term<'a>> {
+    let filename: String = args[0].decode()?;
+
+    match open_workbook_auto(&filename) {
+        Err(ref error) => return Ok(io_error_to_term(env, error)),
+        Ok(ref inner) => Ok((atoms::ok(), inner.sheet_names().to_owned()).encode(env)),
+    }
+}
+
+
+fn parse<'a>(env: Env<'a>, args: &[Term<'a>]) -> NifResult<Term<'a>> {
+    let filename: String = try!(args[0].decode());
+    let sheetname: String = try!(args[1].decode());
+
+    let mut excel = match open_workbook_auto(&filename) {
+        Err(ref error) => return Ok(io_error_to_term(env, error)),
+        Ok(inner) => inner,
+    };
+
+    if let Some(Ok(range)) = excel.worksheet_range(&sheetname) {
+        let row: Vec<(Vec<String>)> = range
+                        .rows()
+                        .into_iter()
+                        .enumerate()
+                        .map(|(_i, col)| 
+                            col
+                            .iter()
+                            .map(|c|
+                                c.to_string()
+                            )
+                            .collect::<Vec<_>>()
+                        )
+                        .collect::<Vec<_>>();
+        
+        Ok((atoms::ok(), row.encode(env)).encode(env))
+    } else {
+        Ok((atoms::error(), "Couldnt find the worksheet").encode(env))
+    }
+}