Bugfix/Buffer Memory for Anthropic (#3242)

fix buffer memory

Author: HenryHengZJ

Diff for: packages/components/nodes/memory/BufferWindowMemory/BufferWindowMemory.ts

@@ -118,14 +118,16 @@ class BufferWindowMemoryExtended extends FlowiseWindowMemory implements MemoryMe
                 sessionId: id,
                 chatflowid: this.chatflowid
             },
-            take: this.k + 1,
             order: {
-                createdDate: 'DESC' // we get the latest top K
+                createdDate: 'ASC'
             }
         })
 
-        // reverse the order of human and ai messages
-        if (chatMessage.length) chatMessage.reverse()
+        if (this.k <= 0) {
+            chatMessage = []
+        } else {
+            chatMessage = chatMessage.slice(-this.k * 2)
+        }
 
         if (prependMessages?.length) {
             chatMessage.unshift(...prependMessages)

Diff for: packages/components/nodes/memory/ConversationSummaryBufferMemory/ConversationSummaryBufferMemory.ts

@@ -10,9 +10,10 @@ import {
 } from '../../../src/Interface'
 import { getBaseClasses, mapChatMessageToBaseMessage } from '../../../src/utils'
 import { BaseLanguageModel } from '@langchain/core/language_models/base'
-import { BaseMessage, getBufferString } from '@langchain/core/messages'
+import { BaseMessage, getBufferString, HumanMessage } from '@langchain/core/messages'
 import { ConversationSummaryBufferMemory, ConversationSummaryBufferMemoryInput } from 'langchain/memory'
 import { DataSource } from 'typeorm'
+import { ChatAnthropic } from '../../chatmodels/ChatAnthropic/FlowiseChatAnthropic'
 
 class ConversationSummaryBufferMemory_Memory implements INode {
     label: string
@@ -163,7 +164,12 @@ class ConversationSummaryBufferMemoryExtended extends FlowiseSummaryBufferMemory
         // ----------- Finished Pruning ---------------
 
         if (this.movingSummaryBuffer) {
-            baseMessages = [new this.summaryChatMessageClass(this.movingSummaryBuffer), ...baseMessages]
+            // Anthropic doesn't support multiple system messages
+            if (this.llm instanceof ChatAnthropic) {
+                baseMessages = [new HumanMessage(`Below is the summarized conversation:\n\n${this.movingSummaryBuffer}`), ...baseMessages]
+            } else {
+                baseMessages = [new this.summaryChatMessageClass(this.movingSummaryBuffer), ...baseMessages]
+            }
         }
 
         if (returnBaseMessages) {

Diff for: packages/components/nodes/memory/ConversationSummaryMemory/ConversationSummaryMemory.ts

@@ -10,9 +10,10 @@ import {
 } from '../../../src/Interface'
 import { getBaseClasses, mapChatMessageToBaseMessage } from '../../../src/utils'
 import { BaseLanguageModel } from '@langchain/core/language_models/base'
-import { BaseMessage, SystemMessage } from '@langchain/core/messages'
+import { BaseMessage, HumanMessage, SystemMessage } from '@langchain/core/messages'
 import { ConversationSummaryMemory, ConversationSummaryMemoryInput } from 'langchain/memory'
 import { DataSource } from 'typeorm'
+import { ChatAnthropic } from '../../chatmodels/ChatAnthropic/FlowiseChatAnthropic'
 
 class ConversationSummaryMemory_Memory implements INode {
     label: string
@@ -135,7 +136,12 @@ class ConversationSummaryMemoryExtended extends FlowiseSummaryMemory implements
         }
 
         if (returnBaseMessages) {
-            return [new SystemMessage(this.buffer)]
+            // Anthropic doesn't support multiple system messages
+            if (this.llm instanceof ChatAnthropic) {
+                return [new HumanMessage(`Below is the summarized conversation:\n\n${this.buffer}`)]
+            } else {
+                return [new SystemMessage(this.buffer)]
+            }
         }
 
         if (this.buffer) {