Add fetchCSV() example macro

1 files changed, 46 insertions, 0 deletions

diff --git a/examples/macros/fetchCSV.tsx b/examples/macros/fetchCSV.tsx
new file mode 100644
index 000000000..0709fd500
--- /dev/null
+++ b/examples/macros/fetchCSV.tsx
@@ -0,0 +1,46 @@
+import Pappa from "papaparse";
+export async function fetchCSV(callExpression) {
+  console.time("fetchCSV Total");
+  const [
+    urlNode,
+    {
+      properties: { last: limit = 10, columns = [] },
+    },
+  ] = callExpression.arguments;
+  const url = urlNode.get();
+
+  console.time("Fetch");
+  const response = await fetch(url);
+  const csvText = await response.text();
+  console.timeEnd("Fetch");
+
+  console.time("Parse");
+  let rows = Pappa.parse(csvText, { fastMode: true }).data;
+  console.timeEnd("Parse");
+
+  console.time("Render");
+  const columnIndices = new Array(columns.length);
+
+  for (let i = 0; i < columns.length; i++) {
+    columnIndices[i] = rows[0].indexOf(columns[i]);
+  }
+
+  rows = rows
+    .slice(Math.max(limit, rows.length) - limit)
+    .reverse()
+    .filter((columns) => columns.every(Boolean));
+  const value = (
+    <array>
+      {rows.map((columns) => (
+        <array>
+          {columnIndices.map((columnIndex) => (
+            <string value={columns[columnIndex]} />
+          ))}
+        </array>
+      ))}
+    </array>
+  );
+  console.timeEnd("Render");
+  console.timeEnd("fetchCSV Total");
+  return value;
+}