Helper to copy vec<u8> to Uint8Array (#38)

src/arrow1/wasm.rs

@@ -1,21 +1,13 @@
+use crate::utils::copy_vec_to_uint8_array;
 use js_sys::Uint8Array;
 use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen(js_name = readParquet)]
 pub fn read_parquet(parquet_file: &[u8]) -> Result<Uint8Array, JsValue> {
-    let buffer = match crate::arrow1::reader::read_parquet(parquet_file) {
-        // This function would return a rust vec that would be copied to a Uint8Array here
-        Ok(buffer) => buffer,
+    match crate::arrow1::reader::read_parquet(parquet_file) {
+        Ok(buffer) => copy_vec_to_uint8_array(buffer),
         Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-
-    let return_len = match (buffer.len() as usize).try_into() {
-        Ok(return_len) => return_len,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-    let return_vec = Uint8Array::new_with_length(return_len);
-    return_vec.copy_from(&buffer);
-    return Ok(return_vec);
+    }
 }
 
 #[wasm_bindgen(js_name = writeParquet)]
@@ -24,17 +16,8 @@ pub fn write_parquet(
     // TODO: make this param optional?
     writer_properties: crate::arrow1::writer_properties::WriterProperties,
 ) -> Result<Uint8Array, JsValue> {
-    let buffer = match crate::arrow1::writer::write_parquet(arrow_file, writer_properties) {
-        // This function would return a rust vec that would be copied to a Uint8Array here
-        Ok(buffer) => buffer,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-
-    let return_len = match (buffer.len() as usize).try_into() {
-        Ok(return_len) => return_len,
+    match crate::arrow1::writer::write_parquet(arrow_file, writer_properties) {
+        Ok(buffer) => copy_vec_to_uint8_array(buffer),
         Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-    let return_vec = Uint8Array::new_with_length(return_len);
-    return_vec.copy_from(&buffer);
-    return Ok(return_vec);
+    }
 }

src/arrow2/wasm.rs

@@ -1,36 +1,19 @@
+use crate::utils::copy_vec_to_uint8_array;
 use js_sys::Uint8Array;
 use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen(js_name = readParquet2)]
 pub fn read_parquet2(parquet_file: &[u8]) -> Result<Uint8Array, JsValue> {
-    let buffer = match crate::arrow2::reader::read_parquet(parquet_file) {
-        // This function would return a rust vec that would be copied to a Uint8Array here
-        Ok(buffer) => buffer,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-
-    let return_len = match (buffer.len() as usize).try_into() {
-        Ok(return_len) => return_len,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-    let return_vec = Uint8Array::new_with_length(return_len);
-    return_vec.copy_from(&buffer);
-    return Ok(return_vec);
+    match crate::arrow2::reader::read_parquet(parquet_file) {
+        Ok(buffer) => copy_vec_to_uint8_array(buffer),
+        Err(error) => Err(JsValue::from_str(format!("{}", error).as_str())),
+    }
 }
 
 #[wasm_bindgen(js_name = writeParquet2)]
 pub fn write_parquet2(arrow_file: &[u8]) -> Result<Uint8Array, JsValue> {
-    let buffer = match crate::arrow2::writer::write_parquet(arrow_file) {
-        // This function would return a rust vec that would be copied to a Uint8Array here
-        Ok(buffer) => buffer,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-
-    let return_len = match (buffer.len() as usize).try_into() {
-        Ok(return_len) => return_len,
-        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
-    };
-    let return_vec = Uint8Array::new_with_length(return_len);
-    return_vec.copy_from(&buffer);
-    return Ok(return_vec);
+    match crate::arrow2::writer::write_parquet(arrow_file) {
+        Ok(buffer) => copy_vec_to_uint8_array(buffer),
+        Err(error) => Err(JsValue::from_str(format!("{}", error).as_str())),
+    }
 }

src/utils.rs

@@ -1,3 +1,6 @@
+use js_sys::Uint8Array;
+use wasm_bindgen::prelude::*;
+
 pub fn set_panic_hook() {
     // When the `console_error_panic_hook` feature is enabled, we can call the
     // `set_panic_hook` function at least once during initialization, and then
@@ -25,3 +28,14 @@ macro_rules! log {
         println!("LOG - {}", format!( $( $t )* ));
     }
 }
+
+/// Copy Vec<u8> to a Uint8Array
+pub fn copy_vec_to_uint8_array(buffer: Vec<u8>) -> Result<Uint8Array, JsValue> {
+    let return_len = match (buffer.len() as usize).try_into() {
+        Ok(return_len) => return_len,
+        Err(error) => return Err(JsValue::from_str(format!("{}", error).as_str())),
+    };
+    let return_vec = Uint8Array::new_with_length(return_len);
+    return_vec.copy_from(&buffer);
+    return Ok(return_vec);
+}