Added Strlen command in node (valkey-io#993)

CHANGELOG.md

@@ -14,6 +14,7 @@
 * Node: Added ZCOUNT command ([#909](https://github.com/aws/glide-for-redis/pull/909))
 * Python: Added ECHO command ([#953](https://github.com/aws/glide-for-redis/pull/953))
 * Python: Added ZPOPMIN command ([#975](https://github.com/aws/glide-for-redis/pull/975))
+* Node: Added STRLEN command ([#993](https://github.com/aws/glide-for-redis/pull/993))
 
 #### Features
 * Python, Node: Added support in Lua Scripts ([#775](https://github.com/aws/glide-for-redis/pull/775), [#860](https://github.com/aws/glide-for-redis/pull/860))

glide-core/src/protobuf/redis_request.proto

@@ -107,6 +107,7 @@ enum RequestType {
     HLen = 69;
     Echo = 70;
     ZPopMin = 71;
+    Strlen = 72;
 }
 
 message Command {

glide-core/src/socket_listener.rs

@@ -350,6 +350,7 @@ fn get_command(request: &Command) -> Option<Cmd> {
         RequestType::HLen => Some(cmd("HLEN")),
         RequestType::Echo => Some(cmd("ECHO")),
         RequestType::ZPopMin => Some(cmd("ZPOPMIN")),
+        RequestType::Strlen => Some(cmd("STRLEN")),
     }
 }
 

node/src/BaseClient.ts

@@ -50,6 +50,7 @@ import {
     createSMembers,
     createSRem,
     createSet,
+    createStrlen,
     createTTL,
     createType,
     createUnlink,
@@ -1066,11 +1067,22 @@ export class BaseClient {
         return this.createWritePromise(createZcount(key, minScore, maxScore));
     }
 
+    /** Returns the length of the string value stored at `key`.
+     * See https://redis.io/commands/strlen/ for more details.
+     *
+     * @param key - The key to check its length.
+     * @returns - The length of the string value stored at key
+     * If `key` does not exist, it is treated as an empty string, and the command returns 0.
+     */
+    public strlen(key: string): Promise<number> {
+        return this.createWritePromise(createStrlen(key));
+    }
+
     /** Returns the string representation of the type of the value stored at `key`.
      * See https://redis.io/commands/type/ for more details.
-     * 
-     * @param key - The key to check its data type.
-     * @returns If the key exists, the type of the stored value is returned. Otherwise, a "none" string is returned.
+     *
+     * @param key - The `key` to check its data type.
+     * @returns If the `key` exists, the type of the stored value is returned. Otherwise, a "none" string is returned.
      */
     public type(key: string): Promise<string> {
         return this.createWritePromise(createType(key));

node/src/Commands.ts

@@ -823,3 +823,10 @@ export function createZcount(
 export function createType(key: string): redis_request.Command {
     return createCommand(RequestType.Type, [key]);
 }
+
+/**
+ * @internal
+ */
+export function createStrlen(key: string): redis_request.Command {
+    return createCommand(RequestType.Strlen, [key]);
+}

node/src/Transaction.ts

@@ -53,6 +53,7 @@ import {
     createSRem,
     createSelect,
     createSet,
+    createStrlen,
     createTTL,
     createType,
     createUnlink,
@@ -840,6 +841,17 @@ export class BaseTransaction<T extends BaseTransaction<T>> {
         return this.addAndReturn(createType(key));
     }
 
+    /** Returns the length of the string value stored at `key`.
+     * See https://redis.io/commands/strlen/ for more details.
+     *
+     * @param key - The `key` to check its length.
+     * Command Response - The length of the string value stored at `key`
+     * If `key` does not exist, it is treated as an empty string, and the command returns 0.
+     */
+    public strlen(key: string): T {
+        return this.addAndReturn(createStrlen(key));
+    }
+
     /** Executes a single command, without checking inputs. Every part of the command, including subcommands,
      *  should be added as a separate value in args.
      *

node/tests/SharedTests.ts

@@ -1390,7 +1390,6 @@ export function runBaseTests<Context>(config: {
         config.timeout
     );
 
-
     it.each([ProtocolVersion.RESP2, ProtocolVersion.RESP3])(
         `zscore test_%p`,
         async (protocol) => {
@@ -1510,6 +1509,32 @@ export function runBaseTests<Context>(config: {
         },
         config.timeout
     );
+
+    it.each([ProtocolVersion.RESP2, ProtocolVersion.RESP3])(
+        `strlen test_%p`,
+        async (protocol) => {
+            await runTest(async (client: BaseClient) => {
+                const key1 = uuidv4();
+                const key1Value = uuidv4();
+                const key1ValueLength = key1Value.length;
+                expect(await client.set(key1, key1Value)).toEqual("OK");
+                expect(await client.strlen(key1)).toEqual(key1ValueLength);
+
+                expect(await client.strlen("nonExistKey")).toEqual(0);
+
+                const listName = "myList";
+                const listKey1Value = uuidv4();
+                const listKey2Value = uuidv4();
+
+                expect(
+                    await client.lpush(listName, [listKey1Value, listKey2Value])
+                ).toEqual(2);
+                // An error is returned when key holds a non-string value
+                await expect(client.strlen(listName)).rejects.toThrow();
+            }, protocol);
+        },
+        config.timeout
+    );
 }
 
 export function runCommonTests<Context>(config: {

node/tests/TestUtilities.ts

@@ -78,6 +78,8 @@ export function transactionTest(
     args.push("OK");
     baseTransaction.mget([key1, key2]);
     args.push(["bar", "baz"]);
+    baseTransaction.strlen(key1);
+    args.push(3);
     baseTransaction.del([key1]);
     args.push(1);
     baseTransaction.hset(key4, { [field]: value });