strudel cli poc

server/sampler.js

@@ -0,0 +1,41 @@
+import fs from 'fs';
+
+export const loadSample = (context, path) => {
+  console.log(`load sample: ${path}`);
+  return new Promise((resolve, reject) => {
+    fs.readFile(new URL(path, import.meta.url), function (err, buffer) {
+      if (err) reject(err);
+      context.decodeAudioData(buffer, resolve);
+    });
+  });
+};
+
+export async function prepareSamples(context, path, ignore = ['.DS_Store', 'Thumbs.db']) {
+  const ignored = (filename) => !ignore.includes(filename);
+  const folders = fs.readdirSync(path).filter(ignored);
+  return Object.fromEntries(
+    await Promise.all(
+      folders.map(async (folder) => {
+        return [
+          folder,
+          await Promise.all(
+            fs
+              .readdirSync(path + folder)
+              .filter(ignored)
+              .map((filename) => path + folder + '/' + filename)
+              .map((filepath) => loadSample(context, filepath)),
+          ),
+        ];
+      }, []),
+    ),
+  );
+}
+
+export const playBuffer = (context, audioBuffer, start = 0) => {
+  const bufferNode = context.createBufferSource();
+  bufferNode.connect(context.destination);
+  bufferNode.buffer = audioBuffer;
+  bufferNode.loop = false;
+  bufferNode.start(start);
+  bufferNode.stop(start + audioBuffer.length / audioBuffer.sampleRate);
+};