Added NeMo Guardrails Chat component (FlowiseAI#3331)

* added: nemoguardrails chat component

* fix: removed options argument from init

fix: generation text has been updated with content string

* fix: lint error fixed

* fix: error when get content

* fix: lint errors

* updated: added handleLLMNewToken for ChatNemoGuardrails

---------

Co-authored-by: patrick <[email protected]>

packages/components/nodes/chatmodels/ChatNemoGuardrails/ChatNemoGuardrails.ts

@@ -0,0 +1,121 @@
+import { BaseChatModel, type BaseChatModelParams } from '@langchain/core/language_models/chat_models'
+import { AIMessageChunk, BaseMessage } from '@langchain/core/messages'
+import { BaseChatModelCallOptions } from '@langchain/core/language_models/chat_models'
+import { NemoClient } from './NemoClient'
+import { CallbackManager, CallbackManagerForLLMRun } from '@langchain/core/callbacks/manager'
+import { ChatResult } from '@langchain/core/outputs'
+import { FailedAttemptHandler } from '@langchain/core/utils/async_caller'
+import { getBaseClasses, INode, INodeData, INodeParams } from '../../../src'
+
+export interface ChatNemoGuardrailsCallOptions extends BaseChatModelCallOptions {
+    /**
+     * An array of strings to stop on.
+     */
+    stop?: string[]
+}
+
+export interface ChatNemoGuardrailsInput extends BaseChatModelParams {
+    configurationId?: string
+    /**
+     * The host URL of the Nemo server.
+     * @default "http://localhost:8000"
+     */
+    baseUrl?: string
+}
+
+class ChatNemoGuardrailsModel extends BaseChatModel<ChatNemoGuardrailsCallOptions, AIMessageChunk> implements ChatNemoGuardrailsInput {
+    configurationId: string
+    id: string
+    baseUrl: string
+    callbackManager?: CallbackManager | undefined
+    maxConcurrency?: number | undefined
+    maxRetries?: number | undefined
+    onFailedAttempt?: FailedAttemptHandler | undefined
+    client: NemoClient
+
+    _llmType(): string {
+        return 'nemo-guardrails'
+    }
+
+    _generate(messages: BaseMessage[], options: this['ParsedCallOptions'], runManager?: CallbackManagerForLLMRun): Promise<ChatResult> {
+        const generate = async (messages: BaseMessage[], client: NemoClient): Promise<ChatResult> => {
+            const chatMessages = await client.chat(messages)
+            const generations = chatMessages.map((message) => {
+                return {
+                    text: message.content?.toString() ?? '',
+                    message
+                }
+            })
+
+            await runManager?.handleLLMNewToken(generations.length ? generations[0].text : '')
+
+            return {
+                generations
+            }
+        }
+        return generate(messages, this.client)
+    }
+
+    constructor({ id, fields }: { id: string; fields: Partial<ChatNemoGuardrailsInput> & BaseChatModelParams }) {
+        super(fields)
+        this.id = id
+        this.configurationId = fields.configurationId ?? ''
+        this.baseUrl = fields.baseUrl ?? ''
+        this.callbackManager = fields.callbackManager
+        this.maxConcurrency = fields.maxConcurrency
+        this.maxRetries = fields.maxRetries
+        this.onFailedAttempt = fields.onFailedAttempt
+        this.client = new NemoClient(this.baseUrl, this.configurationId)
+    }
+}
+
+class ChatNemoGuardrailsChatModel implements INode {
+    label: string
+    name: string
+    version: number
+    type: string
+    icon: string
+    category: string
+    description: string
+    baseClasses: string[]
+    credential: INodeParams
+    inputs: INodeParams[]
+
+    constructor() {
+        this.label = 'Chat Nemo Guardrails'
+        this.name = 'chatNemoGuardrails'
+        this.version = 1.0
+        this.type = 'ChatNemoGuardrails'
+        this.icon = 'nemo.svg'
+        this.category = 'Chat Models'
+        this.description = 'Access models through the Nemo Guardrails API'
+        this.baseClasses = [this.type, ...getBaseClasses(ChatNemoGuardrailsModel)]
+        this.inputs = [
+            {
+                label: 'Configuration ID',
+                name: 'configurationId',
+                type: 'string',
+                optional: false
+            },
+            {
+                label: 'Base URL',
+                name: 'baseUrl',
+                type: 'string',
+                optional: false
+            }
+        ]
+    }
+
+    async init(nodeData: INodeData): Promise<any> {
+        const configurationId = nodeData.inputs?.configurationId
+        const baseUrl = nodeData.inputs?.baseUrl
+        const obj: Partial<ChatNemoGuardrailsInput> = {
+            configurationId: configurationId,
+            baseUrl: baseUrl
+        }
+        const model = new ChatNemoGuardrailsModel({ id: nodeData.id, fields: obj })
+        return model
+    }
+}
+
+module.exports = { nodeClass: ChatNemoGuardrailsChatModel }

packages/components/nodes/chatmodels/ChatNemoGuardrails/NemoClient.ts

@@ -0,0 +1,70 @@
+import { AIMessage, BaseMessage, HumanMessage, SystemMessage } from '@langchain/core/messages'
+
+export interface Config {
+    baseUrl: string
+    configurationId: string
+}
+
+export class ClientConfig implements Config {
+    baseUrl: string
+    configurationId: string
+
+    constructor(baseUrl: string, configurationId: string) {
+        this.baseUrl = baseUrl
+        this.configurationId = configurationId
+    }
+}
+
+export class NemoClient {
+    private readonly config: Config
+
+    constructor(baseUrl: string, configurationId: string) {
+        this.config = new ClientConfig(baseUrl, configurationId)
+    }
+
+    getRoleFromMessage(message: BaseMessage): string {
+        if (message instanceof HumanMessage || message instanceof SystemMessage) {
+            return 'user'
+        }
+
+        //AIMessage, ToolMessage, FunctionMessage
+        return 'assistant'
+    }
+
+    getContentFromMessage(message: BaseMessage): string {
+        return message.content.toString()
+    }
+
+    buildBody(messages: BaseMessage[], configurationId: string): any {
+        const bodyMessages = messages.map((message) => {
+            return {
+                role: this.getRoleFromMessage(message),
+                content: this.getContentFromMessage(message)
+            }
+        })
+
+        const body = {
+            config_id: configurationId,
+            messages: bodyMessages
+        }
+
+        return body
+    }
+
+    async chat(messages: BaseMessage[]): Promise<AIMessage[]> {
+        const headers = new Headers()
+        headers.append('Content-Type', 'application/json')
+
+        const body = this.buildBody(messages, this.config.configurationId)
+
+        const requestOptions = {
+            method: 'POST',
+            body: JSON.stringify(body),
+            headers: headers
+        }
+
+        return await fetch(`${this.config.baseUrl}/v1/chat/completions`, requestOptions)
+            .then((response) => response.json())
+            .then((body) => body.messages.map((message: any) => new AIMessage(message.content)))
+    }
+}

packages/components/nodes/chatmodels/ChatNemoGuardrails/readme.md

@@ -0,0 +1,18 @@
+Parameters:
+
+config_id
+baseUrl
+
+```
+/v1/chat/completions
+```
+
+```json
+{
+    "config_id": "bedrock",
+    "messages": [{
+      "role":"user",
+      "content":"Hello! What can you do for me?"
+    }]
+}
+```