From dbb0d9e392c6c405699991f208f7714e98a81da6 Mon Sep 17 00:00:00 2001
From: streamich <streamich@gmail.com>
Date: Wed, 13 Dec 2023 21:19:27 +0100
Subject: [PATCH] =?UTF-8?q?feat:=20=F0=9F=8E=B8=20improve=20redirects=20lo?=
 =?UTF-8?q?gic?=
MIME-Version: 1.0
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---
 src/cluster/RedisCluster.ts     | 25 +++++++++++++++++--------
 src/cluster/RedisClusterCall.ts | 13 +++++++++++--
 src/demo-cluster.ts             |  5 ++++-
 3 files changed, 32 insertions(+), 11 deletions(-)

diff --git a/src/cluster/RedisCluster.ts b/src/cluster/RedisCluster.ts
index 80848aa..d86251d 100644
--- a/src/cluster/RedisCluster.ts
+++ b/src/cluster/RedisCluster.ts
@@ -60,7 +60,6 @@ export class RedisCluster {
       await this.router.rebuild(client);
       if (this.stopped) return;
       this.initialTableBuildAttempt = 0;
-      console.log('SHARD TABLE CREATED');
       this.onRouter.emit();
     })().catch((error) => {
       const delay = Math.max(Math.min(1000 * 2 ** attempt, 1000 * 60), 1000);
@@ -108,15 +107,18 @@ export class RedisCluster {
   }
 
   private async createClientFromInfo(info: RedisClusterNodeInfo): Promise<RedisClusterNodeClient> {
-    const [client] = await this.createClient({
+    return this.createClientForHost(info.endpoint || info.ip, info.port);
+  }
+
+  private async createClientForHost(host: string, port: number): Promise<RedisClusterNodeClient> {
+    return this.createClient({
       ...this.opts.connectionConfig,
-      host: info.endpoint || info.ip,
-      port: info.port,
+      host,
+      port,
     });
-    return client;
   }
 
-  protected async createClient(config: RedisClusterNodeClientOpts): Promise<[client: RedisClusterNodeClient, id: string]> {
+  protected async createClient(config: RedisClusterNodeClientOpts): Promise<RedisClusterNodeClient> {
     const client = this.createClientRaw(config);
     client.start();
     const {user, pwd} = config;
@@ -124,8 +126,9 @@ export class RedisCluster {
       client.hello(3, pwd, user),
       client.clusterMyId(),
     ]);
+    client.id = id;
     this.router.setClient(id, client);
-    return [client, id];
+    return client;
   }
 
   protected createClientRaw(config: RedisClusterNodeClientOpts): RedisClusterNodeClient {
@@ -154,7 +157,13 @@ export class RedisCluster {
         const redirect = parseMovedError((error as Error).message);
         let host = redirect[0] || client.host;
         if (!host) throw new Error('NO_HOST');
-        // TODO: Start router table rebuild.
+        call.redirects++;
+        if (call.redirects > call.maxRedirects) throw new Error('MAX_REDIRECTS');
+        const port = redirect[1];
+        console.log('redirect', host, port, call.redirects);
+        if (host === client.host && port === client.port) throw new Error('INVALID_REDIRECT');
+        const nextClient = await this.createClientForHost(host, port);
+        return this.callWithClient(call, nextClient);
       }
       throw error;
     }
diff --git a/src/cluster/RedisClusterCall.ts b/src/cluster/RedisClusterCall.ts
index 3b16e60..f066dcc 100644
--- a/src/cluster/RedisClusterCall.ts
+++ b/src/cluster/RedisClusterCall.ts
@@ -5,8 +5,17 @@ import {RedisCall} from "../node";
  */
 export class RedisClusterCall extends RedisCall {
   /**
-   * Key to use for routing the command to the correct node. Used in cluster
-   * mode.
+   * Key to use for routing the command to the correct node.
    */
   public key: string = '';
+
+  /**
+   * Number of redirects that have been performed for this command.
+   */
+  public redirects: number = 0;
+
+  /**
+   * Maximum number of redirects to perform before giving up.
+   */
+  public maxRedirects: number = 4;
 }
diff --git a/src/demo-cluster.ts b/src/demo-cluster.ts
index bdd8b14..451625b 100644
--- a/src/demo-cluster.ts
+++ b/src/demo-cluster.ts
@@ -3,7 +3,9 @@
 import {RedisCluster} from "./cluster/RedisCluster";
 
 const main = async () => {
-  const host = 'localhost';
+  // const host = 'localhost';
+  const host = '127.0.0.1';
+  // const host = '172.17.0.2';
   const port = 7000;
   const user = 'default';
   const pwd = 'AoQhB7bNYljT8IiZ7nbgvSQSXiGHRwQX';
@@ -37,6 +39,7 @@ const main = async () => {
   };
 
   await exec(['SET', 'foo', 'bar']);
+  // await exec(['GET', 'foo']);
 };
 
 main().catch((err) => {