refactor(infra): share jsonl socket requester

src/infra/jsonl-socket.ts

@@ -0,0 +1,59 @@
+import net from "node:net";
+
+export async function requestJsonlSocket<T>(params: {
+  socketPath: string;
+  payload: string;
+  timeoutMs: number;
+  accept: (msg: unknown) => T | null | undefined;
+}): Promise<T | null> {
+  const { socketPath, payload, timeoutMs, accept } = params;
+  return await new Promise((resolve) => {
+    const client = new net.Socket();
+    let settled = false;
+    let buffer = "";
+
+    const finish = (value: T | null) => {
+      if (settled) {
+        return;
+      }
+      settled = true;
+      try {
+        client.destroy();
+      } catch {
+        // ignore
+      }
+      resolve(value);
+    };
+
+    const timer = setTimeout(() => finish(null), timeoutMs);
+
+    client.on("error", () => finish(null));
+    client.connect(socketPath, () => {
+      client.write(`${payload}\n`);
+    });
+    client.on("data", (data) => {
+      buffer += data.toString("utf8");
+      let idx = buffer.indexOf("\n");
+      while (idx !== -1) {
+        const line = buffer.slice(0, idx).trim();
+        buffer = buffer.slice(idx + 1);
+        idx = buffer.indexOf("\n");
+        if (!line) {
+          continue;
+        }
+        try {
+          const msg = JSON.parse(line) as unknown;
+          const result = accept(msg);
+          if (result === undefined) {
+            continue;
+          }
+          clearTimeout(timer);
+          finish(result);
+          return;
+        } catch {
+          // ignore
+        }
+      }
+    });
+  });
+}