feat: skip ready check on NOPERM error

Closes #1293

BREAKING CHANGE: `Redis#serverInfo` is removed. This field is never documented so
you very likely have never used it.

.eslintrc.json

@@ -60,7 +60,7 @@
   },
   "overrides": [
     {
-      "files": ["test/**/*"],
+      "files": ["test/**/*", "test-cluster/**/*"],
       "env": {
         "mocha": true
       },

lib/Redis.ts

@@ -766,6 +766,12 @@ class Redis extends Commander {
     const _this = this;
     this.info(function (err, res) {
       if (err) {
+        if (err.message && err.message.includes("NOPERM")) {
+          console.warn(
+            `Skipping the ready check because INFO command fails: "${err.message}". You can disable ready check with "enableReadyCheck". More: https://github.com/luin/ioredis/wiki/Disable-ready-check.`
+          );
+          return callback(null, {});
+        }
         return callback(err);
       }
       if (typeof res !== "string") {
@@ -799,7 +805,7 @@ class Redis extends Commander {
           _this._readyCheck(callback);
         }, retryTime);
       }
-    });
+    }).catch(noop);
   }
 }
 

lib/redis/event_handler.ts

@@ -88,7 +88,6 @@ export function connectHandler(self) {
             );
           }
         } else {
-          self.serverInfo = info;
           if (self.connector.check(info)) {
             exports.readyHandler(self)();
           } else {

package.json

@@ -49,6 +49,7 @@
     "standard-as-callback": "^2.1.0"
   },
   "devDependencies": {
+    "@types/chai": "^4.3.0",
     "@types/debug": "^4.1.5",
     "@types/lodash.defaults": "^4.2.6",
     "@types/lodash.isarguments": "^3.1.6",

test/functional/connection.ts

@@ -37,7 +37,7 @@ describe("connection", function () {
         redis.disconnect();
         setImmediate(() => done());
       }
-      command.resolve("fake");
+      return command.resolve("fake");
     });
   });
 

test/functional/monitor.ts

@@ -64,10 +64,10 @@ describe("monitor", () => {
   it("should wait for the ready event before monitoring", (done) => {
     const redis = new Redis();
     redis.on("ready", () => {
+      // @ts-expect-error
       const readyCheck = sinon.spy(Redis.prototype, "_readyCheck");
-      redis.monitor(function (err, monitor) {
+      redis.monitor((err, monitor) => {
         expect(readyCheck.callCount).to.eql(1);
-        Redis.prototype._readyCheck.restore();
         redis.disconnect();
         monitor.disconnect();
         done();

test/functional/pipeline.ts

@@ -144,7 +144,7 @@ describe("pipeline", () => {
     const redis = new Redis({ keyPrefix: "foo:" });
     redis.addBuiltinCommand("someCommand");
     sinon.stub(redis, "sendCommand").callsFake((command) => {
-      command.resolve(Buffer.from("OK"));
+      return command.resolve(Buffer.from("OK"));
     });
     const result = await redis.pipeline().someCommand().exec();
     expect(result).to.eql([[null, "OK"]]);

test/functional/ready_check.ts

@@ -1,19 +1,29 @@
 import Redis from "../../lib/Redis";
 import { noop } from "../../lib/utils";
 import * as sinon from "sinon";
+import { expect } from "chai";
+
+const stubInfo = (
+  redis: Redis,
+  response: [Error | null, string | undefined]
+) => {
+  sinon.stub(redis, "info").callsFake((section, callback) => {
+    const cb = typeof section === "function" ? section : callback;
+    const [error, info] = response;
+    cb(error, info);
+    return error ? Promise.reject(error) : Promise.resolve(info);
+  });
+};
 
 describe("ready_check", () => {
   it("should retry when redis is not ready", (done) => {
     const redis = new Redis({ lazyConnect: true });
 
-    sinon.stub(redis, "info").callsFake((callback) => {
-      callback(null, "loading:1\r\nloading_eta_seconds:7");
-    });
+    stubInfo(redis, [null, "loading:1\r\nloading_eta_seconds:7"]);
+
     // @ts-expect-error
-    const stub = sinon.stub(global, "setTimeout").callsFake((body, ms) => {
+    sinon.stub(global, "setTimeout").callsFake((_body, ms) => {
       if (ms === 7000) {
-        redis.info.restore();
-        stub.restore();
         done();
       }
     });
@@ -29,10 +39,25 @@ describe("ready_check", () => {
       },
     });
 
-    sinon.stub(redis, "info").callsFake((callback) => {
-      callback(new Error("info error"));
-    });
+    stubInfo(redis, [new Error("info error"), undefined]);
 
     redis.connect().catch(noop);
   });
+
+  it("warns for NOPERM error", async () => {
+    const redis = new Redis({
+      lazyConnect: true,
+    });
+
+    const warn = sinon.stub(console, "warn");
+    stubInfo(redis, [
+      new Error(
+        "NOPERM this user has no permissions to run the 'info' command"
+      ),
+      undefined,
+    ]);
+
+    await redis.connect();
+    expect(warn.calledOnce).to.eql(true);
+  });
 });