get columns from record batch

Author: domoritz

examples/flights.js

@@ -13,6 +13,7 @@ console.log(table.schema);
 const batch = table.recordBatch(0);
 
 console.log(batch.numRows);
+console.log(batch.columns[3]);
 console.log(batch.numColumns);
 console.log(batch.schema.toJSON());
 console.log(batch.schema.fields);

examples/schema.js

@@ -0,0 +1,17 @@
+const arrow_wasm = require("../pkg/arrow_wasm");
+
+const schema = arrow_wasm.Schema.from({
+  fields: [
+    {
+      name: "number",
+      nullable: false,
+      type: {
+        name: "int",
+        isSigned: true,
+        bitWidth: 32,
+      },
+    },
+  ],
+});
+
+console.log(schema.toJSON());

src/record_batch.rs

@@ -1,4 +1,5 @@
 use crate::{schema, vector};
+use js_sys::Array;
 use wasm_bindgen::prelude::*;
 
 #[wasm_bindgen]
@@ -27,6 +28,20 @@ impl RecordBatch {
         vector::Vector::new(self.0.column(index).clone())
     }
 
+    /// Get all columns in the record batch.
+    // TODO: specify that the output type is Array<Vector>, not Array<any>
+    #[wasm_bindgen(getter)]
+    pub fn columns(&self) -> Array {
+        let vectors: Vec<vector::Vector> = self
+            .0
+            .columns()
+            .into_iter()
+            .map(|column| vector::Vector::new(column.clone()))
+            .collect();
+
+        vectors.into_iter().map(JsValue::from).collect()
+    }
+
     /// Get a column's vector by name.
     #[wasm_bindgen(js_name = columnWithName)]
     pub fn column_with_name(&self, name: &str) -> Result<crate::vector::Vector, JsValue> {