xadd-maxlen-support (#22)

Co-authored-by: Zach Sherbondy <[email protected]>

Author: zeejers

lib/interfaces.ts

@@ -18,7 +18,11 @@ interface RedisStreamOptionsXreadGroup {
   deleteMessagesAfterAck?: boolean;
 }
 
-export type RedisStreamOptions = RedisStreamOptionsXreadGroup;
+interface RedisStreamOptionsXadd {
+  maxLen?: number;
+}
+
+export type RedisStreamOptions = RedisStreamOptionsXreadGroup & RedisStreamOptionsXadd;
 
 // [id, [key, value, key, value]]
 export type RawStreamMessage = [id: string, payload: string[]];

lib/redis.client.ts

@@ -7,6 +7,7 @@ import { RequestsMap } from './requests-map';
 import { deserialize, generateCorrelationId, serialize } from './streams.utils';
 import { RedisStreamContext } from './stream.context';
 import { firstValueFrom, share } from 'rxjs';
+import { RedisValue } from 'ioredis';
 
 @Injectable()
 export class RedisStreamClient extends ClientProxy {
@@ -104,9 +105,16 @@ export class RedisStreamClient extends ClientProxy {
     try {
       if (!this.client) throw new Error('Redis client instance not found.');
 
+      const commandArgs: RedisValue[] = [];
+      if(this.options.streams?.maxLen){
+        commandArgs.push("MAXLEN")
+        commandArgs.push("~")
+        commandArgs.push(this.options.streams.maxLen.toString())
+      }
+      commandArgs.push("*")
       let response = await this.client.xadd(
         stream,
-        '*',
+        ...commandArgs,
         ...serializedPayloadArray,
       );
       return response;

lib/redis.server.ts

@@ -12,6 +12,7 @@ import { CONNECT_EVENT, ERROR_EVENT } from '@nestjs/microservices/constants';
 import { deserialize, serialize } from './streams.utils';
 import { RedisStreamContext } from './stream.context';
 import { Observable } from 'rxjs';
+import { RedisValue } from 'ioredis';
 
 export class RedisStreamStrategy
   extends Server
@@ -148,7 +149,19 @@ export class RedisStreamStrategy
 
           if (!this.client) throw new Error('Redis client instance not found.');
 
-          await this.client.xadd(responseObj.stream, '*', ...serializedEntries);
+          const commandArgs: RedisValue[] = [];
+          if(this.options.streams?.maxLen){
+            commandArgs.push("MAXLEN")
+            commandArgs.push("~")
+            commandArgs.push(this.options.streams.maxLen.toString())
+          }
+          commandArgs.push("*")
+          
+          await this.client.xadd(
+            responseObj.stream,
+            ...commandArgs,
+            ...serializedEntries,
+          );
         }),
       );