feat: keys with scan backend

src/server/redis.js

@@ -6,3 +6,27 @@ const {
 } = process.env;
 
 export default () => redis.createClient(REDIS_PORT, REDIS_HOST);
+
+const safeKeys = async (result, client, pattern, caret) => {
+  do {
+    // eslint-disable-next-line no-await-in-loop, no-loop-func
+    await new Promise((resolve, reject) => {
+      client.scan(caret, 'MATCH', pattern, (error, r) => {
+        if (error) {
+          reject(error);
+          return;
+        }
+        // eslint-disable-next-line no-param-reassign
+        caret = parseInt(r[0], 10);
+        result.push(...r[1]);
+        resolve();
+      });
+    });
+  } while (0 !== caret);
+};
+
+export const keys = async (client, pattern) => {
+  const result = [];
+  await safeKeys(result, client, pattern, 0);
+  return result;
+};