Feature/Update Loop Agentflow (#4957)

HenryHengZJ · web-flow · commit 0065e8f1a0c5 · 2025-09-28T22:08:08.000+01:00
* Feature: Update Loop Agentflow to include fallback message and version increment to 1.1

- Added a new input parameter 'fallbackMessage' to the Loop Agentflow for displaying a message when the loop count is exceeded.
- Incremented the version of Loop Agentflow from 1.0 to 1.1.
- Updated the processing logic to handle the fallback message appropriately when the maximum loop count is reached.

* - Introduced a new input parameter 'loopUpdateState' to allow updating the runtime state during workflow execution.
- Added a method to list runtime state keys for dynamic state management.
- Implemented logic to retrieve and utilize the current loop count in variable resolution.
- Updated the Loop Agentflow output to reflect the new state and final output content.
diff --git a/packages/components/nodes/agentflow/Loop/Loop.ts b/packages/components/nodes/agentflow/Loop/Loop.ts
@@ -1,4 +1,5 @@
 import { ICommonObject, INode, INodeData, INodeOptionsValue, INodeParams } from '../../../src/Interface'
+import { updateFlowState } from '../utils'
 
 class Loop_Agentflow implements INode {
     label: string
@@ -19,7 +20,7 @@ class Loop_Agentflow implements INode {
     constructor() {
         this.label = 'Loop'
         this.name = 'loopAgentflow'
-        this.version = 1.0
+        this.version = 1.1
         this.type = 'Loop'
         this.category = 'Agent Flows'
         this.description = 'Loop back to a previous node'
@@ -40,6 +41,40 @@ class Loop_Agentflow implements INode {
                 name: 'maxLoopCount',
                 type: 'number',
                 default: 5
+            },
+            {
+                label: 'Fallback Message',
+                name: 'fallbackMessage',
+                type: 'string',
+                description: 'Message to display if the loop count is exceeded',
+                placeholder: 'Enter your fallback message here',
+                rows: 4,
+                acceptVariable: true,
+                optional: true
+            },
+            {
+                label: 'Update Flow State',
+                name: 'loopUpdateState',
+                description: 'Update runtime state during the execution of the workflow',
+                type: 'array',
+                optional: true,
+                acceptVariable: true,
+                array: [
+                    {
+                        label: 'Key',
+                        name: 'key',
+                        type: 'asyncOptions',
+                        loadMethod: 'listRuntimeStateKeys',
+                        freeSolo: true
+                    },
+                    {
+                        label: 'Value',
+                        name: 'value',
+                        type: 'string',
+                        acceptVariable: true,
+                        acceptNodeOutputAsVariable: true
+                    }
+                ]
             }
         ]
     }
@@ -58,12 +93,20 @@ class Loop_Agentflow implements INode {
                 })
             }
             return returnOptions
+        },
+        async listRuntimeStateKeys(_: INodeData, options: ICommonObject): Promise<INodeOptionsValue[]> {
+            const previousNodes = options.previousNodes as ICommonObject[]
+            const startAgentflowNode = previousNodes.find((node) => node.name === 'startAgentflow')
+            const state = startAgentflowNode?.inputs?.startState as ICommonObject[]
+            return state.map((item) => ({ label: item.key, name: item.key }))
         }
     }
 
     async run(nodeData: INodeData, _: string, options: ICommonObject): Promise<any> {
         const loopBackToNode = nodeData.inputs?.loopBackToNode as string
         const _maxLoopCount = nodeData.inputs?.maxLoopCount as string
+        const fallbackMessage = nodeData.inputs?.fallbackMessage as string
+        const _loopUpdateState = nodeData.inputs?.loopUpdateState
 
         const state = options.agentflowRuntime?.state as ICommonObject
 
@@ -75,16 +118,34 @@ class Loop_Agentflow implements INode {
             maxLoopCount: _maxLoopCount ? parseInt(_maxLoopCount) : 5
         }
 
+        const finalOutput = 'Loop back to ' + `${loopBackToNodeLabel} (${loopBackToNodeId})`
+
+        // Update flow state if needed
+        let newState = { ...state }
+        if (_loopUpdateState && Array.isArray(_loopUpdateState) && _loopUpdateState.length > 0) {
+            newState = updateFlowState(state, _loopUpdateState)
+        }
+
+        // Process template variables in state
+        if (newState && Object.keys(newState).length > 0) {
+            for (const key in newState) {
+                if (newState[key].toString().includes('{{ output }}')) {
+                    newState[key] = finalOutput
+                }
+            }
+        }
+
         const returnOutput = {
             id: nodeData.id,
             name: this.name,
             input: data,
             output: {
-                content: 'Loop back to ' + `${loopBackToNodeLabel} (${loopBackToNodeId})`,
+                content: finalOutput,
                 nodeID: loopBackToNodeId,
-                maxLoopCount: _maxLoopCount ? parseInt(_maxLoopCount) : 5
+                maxLoopCount: _maxLoopCount ? parseInt(_maxLoopCount) : 5,
+                fallbackMessage
             },
-            state
+            state: newState
         }
 
         return returnOutput
diff --git a/packages/server/src/utils/buildAgentflow.ts b/packages/server/src/utils/buildAgentflow.ts
@@ -43,7 +43,8 @@ import {
     QUESTION_VAR_PREFIX,
     CURRENT_DATE_TIME_VAR_PREFIX,
     _removeCredentialId,
-    validateHistorySchema
+    validateHistorySchema,
+    LOOP_COUNT_VAR_PREFIX
 } from '.'
 import { ChatFlow } from '../database/entities/ChatFlow'
 import { Variable } from '../database/entities/Variable'
@@ -84,6 +85,8 @@ interface IProcessNodeOutputsParams {
     waitingNodes: Map<string, IWaitingNode>
     loopCounts: Map<string, number>
     abortController?: AbortController
+    sseStreamer?: IServerSideEventStreamer
+    chatId: string
 }
 
 interface IAgentFlowRuntime {
@@ -130,6 +133,7 @@ interface IExecuteNodeParams {
     parentExecutionId?: string
     isRecursive?: boolean
     iterationContext?: ICommonObject
+    loopCounts?: Map<string, number>
     orgId: string
     workspaceId: string
     subscriptionId: string
@@ -218,7 +222,8 @@ export const resolveVariables = async (
     chatHistory: IMessage[],
     componentNodes: IComponentNodes,
     agentFlowExecutedData?: IAgentflowExecutedData[],
-    iterationContext?: ICommonObject
+    iterationContext?: ICommonObject,
+    loopCounts?: Map<string, number>
 ): Promise<INodeData> => {
     let flowNodeData = cloneDeep(reactFlowNodeData)
     const types = 'inputs'
@@ -285,6 +290,20 @@ export const resolveVariables = async (
                 resolvedValue = resolvedValue.replace(match, flowConfig?.runtimeChatHistoryLength ?? 0)
             }
 
+            if (variableFullPath === LOOP_COUNT_VAR_PREFIX) {
+                // Get the current loop count from the most recent loopAgentflow node execution
+                let currentLoopCount = 0
+                if (loopCounts && agentFlowExecutedData) {
+                    // Find the most recent loopAgentflow node execution to get its loop count
+                    const loopNodes = [...agentFlowExecutedData].reverse().filter((data) => data.data?.name === 'loopAgentflow')
+                    if (loopNodes.length > 0) {
+                        const latestLoopNode = loopNodes[0]
+                        currentLoopCount = loopCounts.get(latestLoopNode.nodeId) || 0
+                    }
+                }
+                resolvedValue = resolvedValue.replace(match, currentLoopCount.toString())
+            }
+
             if (variableFullPath === CURRENT_DATE_TIME_VAR_PREFIX) {
                 resolvedValue = resolvedValue.replace(match, new Date().toISOString())
             }
@@ -742,7 +761,9 @@ async function processNodeOutputs({
     edges,
     nodeExecutionQueue,
     waitingNodes,
-    loopCounts
+    loopCounts,
+    sseStreamer,
+    chatId
 }: IProcessNodeOutputsParams): Promise<{ humanInput?: IHumanInput }> {
     logger.debug(`\n🔄 Processing outputs from node: ${nodeId}`)
 
@@ -823,6 +844,11 @@ async function processNodeOutputs({
             }
         } else {
             logger.debug(`    ⚠️ Maximum loop count (${maxLoop}) reached, stopping loop`)
+            const fallbackMessage = result.output.fallbackMessage || `Loop completed after reaching maximum iteration count of ${maxLoop}.`
+            if (sseStreamer) {
+                sseStreamer.streamTokenEvent(chatId, fallbackMessage)
+            }
+            result.output = { ...result.output, content: fallbackMessage }
         }
     }
 
@@ -967,6 +993,7 @@ const executeNode = async ({
     isInternal,
     isRecursive,
     iterationContext,
+    loopCounts,
     orgId,
     workspaceId,
     subscriptionId,
@@ -1045,7 +1072,8 @@ const executeNode = async ({
             chatHistory,
             componentNodes,
             agentFlowExecutedData,
-            iterationContext
+            iterationContext,
+            loopCounts
         )
 
         // Handle human input if present
@@ -1889,6 +1917,7 @@ export const executeAgentFlow = async ({
                 analyticHandlers,
                 isRecursive,
                 iterationContext,
+                loopCounts,
                 orgId,
                 workspaceId,
                 subscriptionId,
@@ -1957,7 +1986,8 @@ export const executeAgentFlow = async ({
                 nodeExecutionQueue,
                 waitingNodes,
                 loopCounts,
-                abortController
+                sseStreamer,
+                chatId
             })
 
             // Update humanInput if it was changed
diff --git a/packages/server/src/utils/index.ts b/packages/server/src/utils/index.ts
@@ -69,6 +69,7 @@ export const QUESTION_VAR_PREFIX = 'question'
 export const FILE_ATTACHMENT_PREFIX = 'file_attachment'
 export const CHAT_HISTORY_VAR_PREFIX = 'chat_history'
 export const RUNTIME_MESSAGES_LENGTH_VAR_PREFIX = 'runtime_messages_length'
+export const LOOP_COUNT_VAR_PREFIX = 'loop_count'
 export const CURRENT_DATE_TIME_VAR_PREFIX = 'current_date_time'
 export const REDACTED_CREDENTIAL_VALUE = '_FLOWISE_BLANK_07167752-1a71-43b1-bf8f-4f32252165db'
 
diff --git a/packages/ui/src/ui-component/input/suggestionOption.js b/packages/ui/src/ui-component/input/suggestionOption.js
@@ -71,6 +71,12 @@ export const suggestionOptions = (
                 description: 'Total messsages between LLM and Agent',
                 category: 'Chat Context'
             },
+            {
+                id: 'loop_count',
+                mentionLabel: 'loop_count',
+                description: 'Current loop count',
+                category: 'Chat Context'
+            },
             {
                 id: 'file_attachment',
                 mentionLabel: 'file_attachment',
