add multi prompt chain

packages/components/nodes/chains/ConversationChain/ConversationChain.ts

@@ -56,7 +56,8 @@ class ConversationChain_Chains implements INode {
 
         const obj: any = {
             llm: model,
-            memory
+            memory,
+            verbose: process.env.DEBUG === 'true' ? true : false
         }
 
         const chatPrompt = ChatPromptTemplate.fromPromptMessages([

packages/components/nodes/chains/MultiPromptChain/MultiPromptChain.ts

@@ -0,0 +1,68 @@
+import { BaseLanguageModel } from 'langchain/base_language'
+import { INode, INodeData, INodeParams, PromptRetriever } from '../../../src/Interface'
+import { getBaseClasses } from '../../../src/utils'
+import { MultiPromptChain } from 'langchain/chains'
+
+class MultiPromptChain_Chains implements INode {
+    label: string
+    name: string
+    type: string
+    icon: string
+    category: string
+    baseClasses: string[]
+    description: string
+    inputs: INodeParams[]
+
+    constructor() {
+        this.label = 'Multi Prompt Chain'
+        this.name = 'multiPromptChain'
+        this.type = 'MultiPromptChain'
+        this.icon = 'chain.svg'
+        this.category = 'Chains'
+        this.description = 'Chain automatically picks an appropriate prompt from multiple prompt templates'
+        this.baseClasses = [this.type, ...getBaseClasses(MultiPromptChain)]
+        this.inputs = [
+            {
+                label: 'Language Model',
+                name: 'model',
+                type: 'BaseLanguageModel'
+            },
+            {
+                label: 'Prompt Retriever',
+                name: 'promptRetriever',
+                type: 'PromptRetriever',
+                list: true
+            }
+        ]
+    }
+
+    async init(nodeData: INodeData): Promise<any> {
+        const model = nodeData.inputs?.model as BaseLanguageModel
+        const promptRetriever = nodeData.inputs?.promptRetriever as PromptRetriever[]
+        const promptNames = []
+        const promptDescriptions = []
+        const promptTemplates = []
+
+        for (const prompt of promptRetriever) {
+            promptNames.push(prompt.name)
+            promptDescriptions.push(prompt.description)
+            promptTemplates.push(prompt.systemMessage)
+        }
+
+        const chain = MultiPromptChain.fromPrompts(model, promptNames, promptDescriptions, promptTemplates, undefined, {
+            verbose: process.env.DEBUG === 'true' ? true : false
+        } as any)
+
+        return chain
+    }
+
+    async run(nodeData: INodeData, input: string): Promise<string> {
+        const chain = nodeData.instance as MultiPromptChain
+
+        const res = await chain.call({ input })
+
+        return res?.text
+    }
+}
+
+module.exports = { nodeClass: MultiPromptChain_Chains }

packages/components/nodes/chains/MultiPromptChain/chain.svg

@@ -0,0 +1,6 @@
+<svg xmlns="http://www.w3.org/2000/svg" class="icon icon-tabler icon-tabler-dna" width="24" height="24" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" fill="none" stroke-linecap="round" stroke-linejoin="round">
+   <path stroke="none" d="M0 0h24v24H0z" fill="none"></path>
+   <path d="M14.828 14.828a4 4 0 1 0 -5.656 -5.656a4 4 0 0 0 5.656 5.656z"></path>
+   <path d="M9.172 20.485a4 4 0 1 0 -5.657 -5.657"></path>
+   <path d="M14.828 3.515a4 4 0 0 0 5.657 5.657"></path>
+</svg>

packages/components/nodes/retrievers/PromptRetriever/PromptRetriever.ts

@@ -0,0 +1,62 @@
+import { INode, INodeData, INodeParams, PromptRetriever, PromptRetrieverInput } from '../../../src/Interface'
+
+class PromptRetriever_Retrievers implements INode {
+    label: string
+    name: string
+    description: string
+    type: string
+    icon: string
+    category: string
+    baseClasses: string[]
+    inputs: INodeParams[]
+
+    constructor() {
+        this.label = 'Prompt Retriever'
+        this.name = 'promptRetriever'
+        this.type = 'PromptRetriever'
+        this.icon = 'promptretriever.svg'
+        this.category = 'Retrievers'
+        this.description = 'Store prompt template with name & description to be later queried by MultiPromptChain'
+        this.baseClasses = [this.type]
+        this.inputs = [
+            {
+                label: 'Prompt Name',
+                name: 'name',
+                type: 'string',
+                placeholder: 'physics-qa'
+            },
+            {
+                label: 'Prompt Description',
+                name: 'description',
+                type: 'string',
+                rows: 3,
+                description: 'Description of what the prompt does and when it should be used',
+                placeholder: 'Good for answering questions about physics'
+            },
+            {
+                label: 'Prompt System Message',
+                name: 'systemMessage',
+                type: 'string',
+                rows: 4,
+                placeholder: `You are a very smart physics professor. You are great at answering questions about physics in a concise and easy to understand manner. When you don't know the answer to a question you admit that you don't know.`
+            }
+        ]
+    }
+
+    async init(nodeData: INodeData): Promise<any> {
+        const name = nodeData.inputs?.name as string
+        const description = nodeData.inputs?.description as string
+        const systemMessage = nodeData.inputs?.systemMessage as string
+
+        const obj = {
+            name,
+            description,
+            systemMessage
+        } as PromptRetrieverInput
+
+        const retriever = new PromptRetriever(obj)
+        return retriever
+    }
+}
+
+module.exports = { nodeClass: PromptRetriever_Retrievers }

packages/components/nodes/retrievers/PromptRetriever/promptretriever.svg

@@ -0,0 +1,8 @@
+<svg xmlns="http://www.w3.org/2000/svg" class="icon icon-tabler icon-tabler-message-down" width="24" height="24" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor" fill="none" stroke-linecap="round" stroke-linejoin="round">
+   <path stroke="none" d="M0 0h24v24H0z" fill="none"></path>
+   <path d="M8 9h8"></path>
+   <path d="M8 13h6"></path>
+   <path d="M11.998 18.601l-3.998 2.399v-3h-2a3 3 0 0 1 -3 -3v-8a3 3 0 0 1 3 -3h12a3 3 0 0 1 3 3v5.5"></path>
+   <path d="M19 16v6"></path>
+   <path d="M22 19l-3 3l-3 -3"></path>
+</svg>

packages/components/src/Interface.ts

@@ -103,3 +103,24 @@ export class PromptTemplate extends LangchainPromptTemplate {
         super(input)
     }
 }
+
+export interface PromptRetrieverInput {
+    name: string
+    description: string
+    systemMessage: string
+}
+
+const fixedTemplate = `Here is a question:
+{input}
+`
+export class PromptRetriever {
+    name: string
+    description: string
+    systemMessage: string
+
+    constructor(fields: PromptRetrieverInput) {
+        this.name = fields.name
+        this.description = fields.description
+        this.systemMessage = `${fields.systemMessage}\n${fixedTemplate}`
+    }
+}