feat: API indexer-status endpoint

frontend/src/pages/api/status-indexer.js

@@ -0,0 +1,27 @@
+import { getNearNetwork } from "../../libraries/config";
+import { ExplorerApi } from "../../libraries/explorer-wamp";
+import BlocksApi from "../../libraries/explorer-wamp/blocks";
+
+export default async function (req, res) {
+  // This endpoint provides the status of Indexer for Explorer
+  // It checks the latest block height in indexer database
+  // and the latest block height from JSON RPC
+  // If the difference in between 30 blocks it is considered as fine
+  // otherwise not fine
+
+  try {
+    const rpcFinalBlock = await new ExplorerApi(req).call(
+      "nearcore-final-block"
+    );
+    const indexerFinalBlock = await new BlocksApi(req).getBlocks(1, null);
+
+    const statusResponse = {
+      rpc_latest_block_height: rpcFinalBlock.header.height,
+      indexer_latest_block_height: indexerFinalBlock[0].height,
+    };
+    res.status(200).send(statusResponse);
+  } catch (error) {
+    console.error(error);
+    res.status(502).send(error);
+  }
+}