Batch outspends requests

fixes #1902

backend/src/routes.ts

@@ -120,6 +120,30 @@ class Routes {
     res.json(times);
   }
 
+  public async $getBatchedOutspends(req: Request, res: Response) {
+    if (!Array.isArray(req.query.txId)) {
+      res.status(500).send('Not an array');
+      return;
+    }
+    if (req.query.txId.length > 50) {
+      res.status(400).send('Too many txids requested');
+      return;
+    }
+    const txIds: string[] = [];
+    for (const _txId in req.query.txId) {
+      if (typeof req.query.txId[_txId] === 'string') {
+        txIds.push(req.query.txId[_txId].toString());
+      }
+    }
+
+    try {
+      const batchedOutspends = await bitcoinApi.$getBatchedOutspends(txIds);
+      res.json(batchedOutspends);
+    } catch (e) {
+      res.status(500).send(e instanceof Error ? e.message : e);
+    }
+  }
+
   public getCpfpInfo(req: Request, res: Response) {
     if (!/^[a-fA-F0-9]{64}$/.test(req.params.txId)) {
       res.status(501).send(`Invalid transaction ID.`);