From 746da81725f83080fcc901fd483d5bfcc53ba385 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Karol=20Wypch=C5=82o?= <kwypchlo@gmail.com>
Date: Thu, 3 Sep 2020 15:08:55 +0200
Subject: [PATCH] cache hns response for 5 minutes (#366)

---
 packages/handshake-api/package.json |  3 ++-
 packages/handshake-api/src/index.js |  6 ++++++
 yarn.lock                           | 12 ++++++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/packages/handshake-api/package.json b/packages/handshake-api/package.json
index 2e6850ce..fbbf3a32 100644
--- a/packages/handshake-api/package.json
+++ b/packages/handshake-api/package.json
@@ -6,7 +6,8 @@
   "dependencies": {
     "express": "^4.17.1",
     "express-http-proxy": "^1.6.2",
-    "hs-client": "^0.0.9"
+    "hs-client": "^0.0.9",
+    "node-cache": "^5.1.2"
   },
   "devDependencies": {
     "prettier": "^2.0.5"
diff --git a/packages/handshake-api/src/index.js b/packages/handshake-api/src/index.js
index 6c057ca1..fa522387 100644
--- a/packages/handshake-api/src/index.js
+++ b/packages/handshake-api/src/index.js
@@ -1,6 +1,7 @@
 const url = require("url");
 const express = require("express");
 const proxy = require("express-http-proxy");
+const NodeCache = require("node-cache");
 const { NodeClient } = require("hs-client");
 
 const host = process.env.HOSTNAME || "0.0.0.0";
@@ -18,16 +19,21 @@ const clientOptions = {
   apiKey: hsdApiKey,
 };
 const client = new NodeClient(clientOptions);
+const cache = new NodeCache({ stdTTL: 300 }); // cache for 5 minutes
 
 // Match both `sia://HASH` and `HASH` links.
 const startsWithSkylinkRegExp = /^(sia:\/\/)?[a-zA-Z0-9_-]{46}/;
 
 const getDomainRecords = async (name) => {
+  if (cache.has(name)) return cache.get(name);
+
   const response = await client.execute("getnameresource", [name]);
   const records = response?.records ?? null;
 
   console.log(`${name} => ${JSON.stringify(records)}`);
 
+  cache.set(name, records);
+
   return records;
 };
 
diff --git a/yarn.lock b/yarn.lock
index 5c958731..815f171e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3928,6 +3928,11 @@ clone-response@1.0.2, clone-response@^1.0.2:
   dependencies:
     mimic-response "^1.0.0"
 
+clone@2.x:
+  version "2.1.2"
+  resolved "https://registry.yarnpkg.com/clone/-/clone-2.1.2.tgz#1b7f4b9f591f1e8f83670401600345a02887435f"
+  integrity sha1-G39Ln1kfHo+DZwQBYANFoCiHQ18=
+
 coa@^2.0.2:
   version "2.0.2"
   resolved "https://registry.yarnpkg.com/coa/-/coa-2.0.2.tgz#43f6c21151b4ef2bf57187db0d73de229e3e7ec3"
@@ -10238,6 +10243,13 @@ node-addon-api@^3.0.0:
   resolved "https://registry.yarnpkg.com/node-addon-api/-/node-addon-api-3.0.0.tgz#812446a1001a54f71663bed188314bba07e09247"
   integrity sha512-sSHCgWfJ+Lui/u+0msF3oyCgvdkhxDbkCS6Q8uiJquzOimkJBvX6hl5aSSA7DR1XbMpdM8r7phjcF63sF4rkKg==
 
+node-cache@^5.1.2:
+  version "5.1.2"
+  resolved "https://registry.yarnpkg.com/node-cache/-/node-cache-5.1.2.tgz#f264dc2ccad0a780e76253a694e9fd0ed19c398d"
+  integrity sha512-t1QzWwnk4sjLWaQAS8CHgOJ+RAfmHpxFWmc36IWTiWHQfs0w5JDMBS1b1ZxQteo0vVVuWJvIUKHDkkeK7vIGCg==
+  dependencies:
+    clone "2.x"
+
 node-emoji@^1.10.0:
   version "1.10.0"
   resolved "https://registry.yarnpkg.com/node-emoji/-/node-emoji-1.10.0.tgz#8886abd25d9c7bb61802a658523d1f8d2a89b2da"