LangChain integration with Azure Database for PostgreSQL (Part 1)
Use LangChain to split documents into smaller chunks, generate embeddings for each chunk using Azure OpenAI, and store them in a PostgreSQL database via the pgvector extension. Then, we’ll perform a vector similarity search on the embedded documents.Democratizing Data: Unleashing Power of AI Analytics with LangChain and Azure OpenAI Services
Explore how LangChain and Azure OpenAI Services are revolutionizing data analytics. Discover the transformative potential of Generative AI and Large Language Models in making data analytics accessible to everyone, irrespective of their coding expertise or data science background. Dive into the behind-the-scenes magic of the LangChain agent and learn how it simplifies the user experience by dynamically generating Python code for data analysis.How to build Tool-calling Agents with Azure OpenAI and Lang Graph
Introducing MyTreat Our demo is a fictional website that shows customers their total bill in dollars, but they have the option of getting the total bill in their local currencies. The button sends a request to the Node.js service and a response is simply returned from our Agent given the tool it chooses. Let’s dive in and understand how this works from a broader perspective. Prerequisites An active Azure subscription. You can sign up for a free trial here or get $100 worth of credits on Azure every year if you are a student. A GitHub account (not necessarily) Node.js LTS 18 + VS Code installed (or your favorite IDE) Basic knowledge of HTML, CSS, JS Creating an Azure OpenAI Resource Go over to your browser and key in portal.azure.com to access the Microsoft Azure Portal. Over there navigate to the search bar and type Azure OpenAI. Go ahead and click on + Create. Fill in the input boxes with appropriate, for example, as shown below then press on next until you reach review and submit then finally click on Create. After the deployment is done, go to the deployment and access Azure AI Foundry portal using the button as show below. You can also use the link as demonstrated below. In the Azure AI Foundry portal, we have to create our model instance so we have to go over to Model Catalog on the left panel beneath Get Started. Select a desired model, in this case I used gpt-35-turbo for chat completion (in your case use gpt-4o). Below is a way of doing this. Choose a model (gpt-4o) Click on deploy Give the deployment a new name e.g. myTreatmodel, then click deploy and wait for it to finish On the left panel go over to deployments and you will see the model you have created. Access your Azure OpenAI Resource Key Go back to Azure portal and specifically to the deployment instance that we have and select on the left panel, Resource Management. Click on Keys and Endpoints. Copy any of the keys as shown below and keep it very safe as we will use it in our .env file. Configuring your project Create a new project folder on your local machine and add these variables to the .env file in the root folder. AZURE_OPENAI_API_INSTANCE_NAME= AZURE_OPENAI_API_DEPLOYMENT_NAME= AZURE_OPENAI_API_KEY= AZURE_OPENAI_API_VERSION="2024-08-01-preview" LANGCHAIN_TRACING_V2="false" LANGCHAIN_CALLBACKS_BACKGROUND = "false" PORT=4556 Starting a new project Go over to https://github.com/tiprock-network/mytreat.git and follow the instructions to setup the new project, if you do not have git installed, go over to the Code button and press Download ZIP. This will enable you get the project folder and follow the same procedure for setting up. Creating a custom tool In the utils folder the math tool was created, this code show below uses tool from Langchain to build a tool and the schema of the tool is created using zod.js, a library that helps in validating an object’s property value. The price function takes in an array of prices and the exchange rate, adds the prices up and converts them using the exchange rate as shown below. import { tool } from '@langchain/core/tools' import { z } from 'zod' const priceConv = tool((input) =>{ //get the prices and add them up after turning each into let sum = 0 input.prices.forEach((price) => { let price_check = parseFloat(price) sum += price_check }) //now change the price using exchange rate let final_price = parseFloat(input.exchange_rate) * sum //return return final_price },{ name: 'add_prices_and_convert', description: 'Add prices and convert based on exchange rate.', schema: z.object({ prices: z.number({ required_error: 'Price should not be empty.', invalid_type_error: 'Price must be a number.' }).array().nonempty().describe('Prices of items listed.'), exchange_rate: z.string().describe('Current currency exchange rate.') }) }) export { priceConv } Utilizing the tool In the controller’s folder we then bring the tool in by importing it. After that we pass it in to our array of tools. Notice that we have the Tavily Search Tool, you can learn how to implement in the Additional Reads Section or just remove it. Agent Model and the Call Process This code defines an AI agent using LangGraph and LangChain.js, powered by GPT-4o from Azure OpenAI. It initializes a ToolNode to manage tools like priceConv and binds them to the agent model. The StateGraph handles decision-making, determining whether the agent should call a tool or return a direct response. If a tool is needed, the workflow routes the request accordingly; otherwise, the agent responds to the user. The callModel function invokes the agent, processing messages and ensuring seamless tool integration. The searchAgentController is a GET endpoint that accepts user queries (text_message). It processes input through the compiled LangGraph workflow, invoking the agent to generate a response. If a tool is required, the agent calls it before finalizing the output. The response is then sent back to the user, ensuring dynamic and efficient tool-assisted reasoning. //create tools the agent will use //const agentTools = [new TavilySearchResults({maxResults:5}), priceConv] const agentTools = [ priceConv] const toolNode = new ToolNode(agentTools) const agentModel = new AzureChatOpenAI({ model:'gpt-4o', temperature:0, azureOpenAIApiKey: AZURE_OPENAI_API_KEY, azureOpenAIApiInstanceName:AZURE_OPENAI_API_INSTANCE_NAME, azureOpenAIApiDeploymentName:AZURE_OPENAI_API_DEPLOYMENT_NAME, azureOpenAIApiVersion:AZURE_OPENAI_API_VERSION }).bindTools(agentTools) //make a decision to continue or not const shouldContinue = ( state ) => { const { messages } = state const lastMessage = messages[messages.length -1] //upon tool call we go to tools if("tool_calls" in lastMessage && Array.isArray(lastMessage.tool_calls) && lastMessage.tool_calls?.length) return "tools"; //if no tool call is made we stop and return back to the user return END } const callModel = async (state) => { const response = await agentModel.invoke(state.messages) return { messages: [response] } } //define a new graph const workflow = new StateGraph(MessagesAnnotation) .addNode("agent", callModel) .addNode("tools", toolNode) .addEdge(START, "agent") .addConditionalEdges("agent", shouldContinue, ["tools", END]) .addEdge("tools", "agent") const appAgent = workflow.compile() The above is implemented with the following code: Frontend The frontend is a simple HTML+CSS+JS stack that demonstrated how you can use an API to integrate this AI Agent to your website. It sends a GET request and uses the response to get back the right answer. Below is an illustration of how fetch API has been used. const searchAgentController = async ( req, res ) => { //get human text const { text_message } = req.query if(!text_message) return res.status(400).json({ message:'No text sent.' }) //invoke the agent const agentFinalState = await appAgent.invoke( { messages: [new HumanMessage(text_message)] }, {streamMode: 'values'} ) //const agentFinalState_b = await agentModel.invoke(text_message) /*return res.status(200).json({ answer:agentFinalState.messages[agentFinalState.messages.length - 1].content })*/ //console.log(agentFinalState_b.tool_calls) res.status(200).json({ text: agentFinalState.messages[agentFinalState.messages.length - 1].content }) } There you go! We have created a basic tool-calling agent using Azure and Langchain successfully, go ahead and expand the code base to your liking. If you have questions you can comment below or reach out on my socials. Additional Reads Azure Open AI Service Models Generative AI for Beginners AI Agents for Beginners Course Lang Graph Tutorial Develop Generative AI Apps in Azure AI Foundry PortalBuild Enterprise-Ready AI Agents with the New Azure Postgres LangChain + LangGraph Connector
AI agents are only as powerful as the data layer behind them. That’s why we’re excited to announce native LangChain + LangGraph connector for Azure Database for PostgreSQL. With this release, Postgres becomes your single source of truth for AI agents, handling knowledge retrieval, chat history, and long-term memory all in one place. This new connector is packed with everything you need to build secure, scalable and enterprise-ready AI agents on Azure without the complexity. With EntraID authentication, DiskANN acceleration, vector store, and a dedicated agent store, you can go from prototype to production on Azure faster than ever. You can quickly get started with the LangChain + LangGraph connector today pip install langchain-azure-postgresql In this post, we’ll cover: How Azure Postgres connector for LangGraph can serve as the single persistence + retrieval layer for an AI agent New first-class connector for LangChain +LangGraph A practical example to help you get started Azure PostgreSQL as the single persistence + retrieval layer for an AI agent When building AI agents today, developers face a fragmented stack: Vector storage and search require a library, service or separate database. Chat history & short-term memory need yet another data source. Long-term memory often means bolting on yet another system. This sprawl leads to complex integrations, higher costs, and weaker security, making it hard to scale AI agents reliably. The Solution The new Azure Postgres connector for LangChain + LangGraph transforms your Azure Postgres database to the single persistence + retrieval layer for AI agents. Instead of working on a fragmented stack, developers can now: Run embeddings + semantic search with built-in DiskANN acceleration in the same database that powers their application logic. Persist chat history and short-term memory and keep agent conversations grounded via seamless context retrieval from data stored in Postgres. Capture, retrieve, and evolve knowledge over time with a built-in long-term memory without bolting on external systems. All in one database, simplified, secure, and enterprise ready. Postgres becomes the persistent and retrieval data layer for your AI agent. Built for Enterprise Readiness: LangChain + LangGraph Connector This release unlocks several new capabilities that make it easy to build robust, production-ready agents: Auth with EntraID: Enterprise-grade identity to securely connect LangChain + LangGraph workflows to Azure Database for PostgreSQL within a centrally managed security perimeter based on identity. DiskANN & Extensions: First-class support for faster vector search using pgvector combined with DiskANN indexing, enabling support for high-dimensional vectors and cost-efficient search. Additionally, helper functions ensure your favorite extensions are installed. Native Vector Store: Store and query embeddings, enabling semantic search and Retrieval-Augmented Generation (RAG) scenarios. Dedicated Agent Store: Persist agent state, memory, and chat history with structured access patterns, perfect for multi-turn conversations and long-term context. Together, these features give developers a turnkey persistence solution for building reliable AI agents without stitching together multiple storage systems. Using LangGraph on Azure Database for PostgreSQL Using LangGraph with Azure Database for PostgreSQL is easy. Enable the vector & pg_diskann Extension: Allowlist the vector and pg_diskann extension within your server configuration. Import LangChain + LangGraph connector pip install langchain-azure-postgresql pip install -qU langchain-openai pip install -qU azure-identity Login to Azure, to your Entra ID Run az login in your terminal, where you will also run the LangGraph code. az login To get started, you need to set up a production-ready vector store for your agent in a few lines of code. # 1. Auth: Securely connect to Azure Postgres connection_pool = AzurePGConnectionPool(azure_conn_info=ConnectionInfo(host=os.environ["PGHOST"])) #2. Create embeddings embeddings = AzureOpenAIEmbeddings(model="text-embedding-3-small") # 3. Initialize a vector store in Postgres with DiskANN vector_store = AzurePGVectorStore(connection=connection, embedding=embeddings) Use LangGraph to build a sample agent. Here’s a practical example that combines vector search and checkpointer inside Postgres: #4 Define the tool for data retrieval. def get_data_from_vector_store(query: str) -> str: """Get data from the vector store.""" results = vector_store.similarity_search(query) return results #5 Define the agent, checkpointer and memory store. with connection_pool.getconn() as conn: agent = create_react_agent( model=model, tools=[get_data_from_vector_store], checkpointer=PostgresSaver(conn) ) #6 Run the agent and print results config = {"configurable": {"thread_id": "1", "user_id": "1"}} response = agent.invoke( {"messages": [{"role": "user", "content": "What does my database say about cats? Make sure you address me with my name"}]}, config ) for msg in response["messages"][-2:]: msg.pretty_print() With just a few lines of code, you can: Uses the vector store backed by Postgres Enable DiskANN for semantic search Use checkpointers for short-term conversation history Learn More This is just the beginning. With native LangChain + LangGraph support in Azure PostgreSQL, developers can now rely on a single, secure, high-performance data layer for building the next generation of AI agents. 👉 Ready to start? All the code are available in the Azure Postgres Agents Demo GitHub repository. See how easy it is to bring your AI agent to life on Azure. 👉 Check out the docs for more details on the LangChain + LangGraph connector.Don't miss the 2024 Azure Developers JavaScript Day!
Do you want to discover the latest services and features in Azure designed specifically for JavaScript developers? Are you looking for cutting-edge cloud development techniques that can save you time and money, while providing your customers with the best experience possible?How to use any Python AI agent framework with free GitHub Models
I ❤️ when companies offer free tiers for developer services, since it gives everyone a way to learn new technologies without breaking the bank. Free tiers are especially important for students and people between jobs, when the desire to learn is high but the available cash is low. That's why I'm such a fan of GitHub Models: free, high-quality generative AI models available to anyone with a GitHub account. The available models include the latest OpenAI LLMs (like o3-mini), LLMs from the research community (like Phi and Llama), LLMs from other popular providers (like Mistral and Jamba), multimodal models (like gpt-4o and llama-vision-instruct) and even a few embedding models (from OpenAI and Cohere). With access to such a range of models, you can prototype complex multi-model workflows to improve your productivity or heck, just make something fun for yourself. 🤗 To use GitHub Models, you can start off in no-code mode: open the playground for a model, send a few requests, tweak the parameters, and check out the answers. When you're ready to write code, select "Use this model". A screen will pop up where you can select a programming language (Python/JavaScript/C#/Java/REST) and select an SDK (which varies depending on model). Then you'll get instructions and code for that model, language, and SDK. But here's what's really cool about GitHub Models: you can use them with all the popular Python AI frameworks, even if the framework has no specific integration with GitHub Models. How is that possible? The vast majority of Python AI frameworks support the OpenAI Chat Completions API, since that API became a defacto standard supported by many LLM API providers besides OpenAI itself. GitHub Models also provide OpenAI-compatible endpoints for chat completion models. Therefore, any Python AI framework that supports OpenAI-like models can be used with GitHub Models as well. 🎉 To prove it, I've made a new repository with examples from eight different Python AI agent packages, all working with GitHub Models: python-ai-agent-frameworks-demos. There are examples for AutoGen, LangGraph, Llamaindex, OpenAI Agents SDK, OpenAI standard SDK, PydanticAI, Semantic Kernel, and SmolAgents. You can open that repository in GitHub Codespaces, install the packages, and get the examples running immediately. Now let's walk through the API connection code for GitHub Models for each framework. Even if I missed your favorite framework, I hope my tips here will help you connect any framework to GitHub Models. OpenAI I'll start with openai , the package that started it all! import openai client = openai.OpenAI( api_key=os.environ["GITHUB_TOKEN"], base_url="https://models.inference.ai.azure.com") The code above demonstrates the two key parameters we'll need to configure for all frameworks: api_key : When using OpenAI.com, you pass your OpenAI API key here. When using GitHub Models, you pass in a Personal Access Token (PAT). If you open the repository (or any repository) in GitHub Codespaces, a PAT is already stored in the GITHUB_TOKEN environment variable. However, if you're working locally with GitHub Models, you'll need to generate a PAT yourself and store it. PATs expire after a while, so you need to generate new PATs every so often. base_url : This parameter tells the OpenAI client to send all requests to "https://models.inference.ai.azure.com" instead of the OpenAI.com API servers. That's the domain that hosts the OpenAI-compatible endpoint for GitHub Models, so you'll always pass that domain as the base URL. If we're working with the new openai-agents SDK, we use very similar code, but we must use the AsyncOpenAI client from openai instead. Lately, Python AI packages are defaulting to async, because it's so much better for performance. import agents import openai client = openai.AsyncOpenAI( base_url="https://models.inference.ai.azure.com", api_key=os.environ["GITHUB_TOKEN"]) model = agents.OpenAIChatCompletionsModel( model="gpt-4o", openai_client=client) spanish_agent = agents.Agent( name="Spanish agent", instructions="You only speak Spanish.", model=model) PydanticAI Now let's look at all of the packages that make it really easy for us, by allowing us to directly bring in an instance of either OpenAI or AsyncOpenAI . For PydanticAI, we configure an AsyncOpenAI client, then construct an OpenAIModel object from PydanticAI, and pass that model to the agent: import openai import pydantic_ai import pydantic_ai.models.openai client = openai.AsyncOpenAI( api_key=os.environ["GITHUB_TOKEN"], base_url="https://models.inference.ai.azure.com") model = pydantic_ai.models.openai.OpenAIModel( "gpt-4o", provider=OpenAIProvider(openai_client=client)) spanish_agent = pydantic_ai.Agent( model, system_prompt="You only speak Spanish.") Semantic Kernel For Semantic Kernel, the code is very similar. We configure an AsyncOpenAI client, then construct an OpenAIChatCompletion object from Semantic Kernel, and add that object to the kernel. import openai import semantic_kernel.connectors.ai.open_ai import semantic_kernel.agents chat_client = openai.AsyncOpenAI( api_key=os.environ["GITHUB_TOKEN"], base_url="https://models.inference.ai.azure.com") chat = semantic_kernel.connectors.ai.open_ai.OpenAIChatCompletion( ai_model_id="gpt-4o", async_client=chat_client) kernel.add_service(chat) spanish_agent = semantic_kernel.agents.ChatCompletionAgent( kernel=kernel, name="Spanish agent" instructions="You only speak Spanish") AutoGen Next, we'll check out a few frameworks that have their own wrapper of the OpenAI clients, so we won't be using any classes from openai directly. For AutoGen, we configure both the OpenAI parameters and the model name in the same object, then pass that to each agent: import autogen_ext.models.openai import autogen_agentchat.agents client = autogen_ext.models.openai.OpenAIChatCompletionClient( model="gpt-4o", api_key=os.environ["GITHUB_TOKEN"], base_url="https://models.inference.ai.azure.com") spanish_agent = autogen_agentchat.agents.AssistantAgent( "spanish_agent", model_client=client, system_message="You only speak Spanish") LangGraph For LangGraph, we configure a very similar object, which even has the same parameter names: import langchain_openai import langgraph.graph model = langchain_openai.ChatOpenAI( model="gpt-4o", api_key=os.environ["GITHUB_TOKEN"], base_url="https://models.inference.ai.azure.com", ) def call_model(state): messages = state["messages"] response = model.invoke(messages) return {"messages": [response]} workflow = langgraph.graph.StateGraph(MessagesState) workflow.add_node("agent", call_model) SmolAgents Once again, for SmolAgents, we configure a similar object, though with slightly different parameter names: import smolagents model = smolagents.OpenAIServerModel( model_id="gpt-4o", api_key=os.environ["GITHUB_TOKEN"], api_base="https://models.inference.ai.azure.com") agent = smolagents.CodeAgent(model=model) Llamaindex I saved Llamaindex for last, as it is the most different. The llama-index package has a different constructor for OpenAI.com versus OpenAI-like servers, so I opted to use that OpenAILike constructor instead. However, I also needed an embeddings model for my example, and the package doesn't have an OpenAIEmbeddingsLike constructor, so I used the standard OpenAIEmbedding constructor. import llama_index.embeddings.openai import llama_index.llms.openai_like import llama_index.core.agent.workflow Settings.llm = llama_index.llms.openai_like.OpenAILike( model="gpt-4o", api_key=os.environ["GITHUB_TOKEN"], api_base="https://models.inference.ai.azure.com", is_chat_model=True) Settings.embed_model = llama_index.embeddings.openai.OpenAIEmbedding( model="text-embedding-3-small", api_key=os.environ["GITHUB_TOKEN"], api_base="https://models.inference.ai.azure.com") agent = llama_index.core.agent.workflow.ReActAgent( tools=query_engine_tools, llm=Settings.llm) Choose your models wisely! In all of the examples above, I specified the gpt-4o model. The gpt-4o model is a great choice for agents because it supports function calling, and many agent frameworks only work (or work best) with models that natively support function calling. Fortunately, GitHub Models includes multiple models that support function calling, at least in my basic experiments: gpt-4o gpt-4o-mini o3-mini AI21-Jamba-1.5-Large AI21-Jamba-1.5-Mini Codestral-2501 Cohere-command-r Ministral-3B Mistral-Large-2411 Mistral-Nemo Mistral-small You might find that some models work better than others, especially if you're using agents with multiple tools. With GitHub Models, it's very easy to experiment and see for yourself, by simply changing the model name and re-running the code. Join the AI Agents Hackathon We are currently running a free virtual hackathon from April 8th - 30th, to challenge developers to create agentic applications using Microsoft technologies. You could build an agent entirely using GitHub Models and submit it to the hackathon for a chance to win amazing prizes! You can also join our 30+ streams about building AI agents, including a stream all about prototyping with GitHub Models. Learn more and register at https://aka.ms/agentshackCreate your own QA RAG Chatbot with LangChain.js + Azure OpenAI Service
Demo: Mpesa for Business Setup QA RAG Application In this tutorial we are going to build a Question-Answering RAG Chat Web App. We utilize Node.js and HTML, CSS, JS. We also incorporate Langchain.js + Azure OpenAI + MongoDB Vector Store (MongoDB Search Index). Get a quick look below. Note: Documents and illustrations shared here are for demo purposes only and Microsoft or its products are not part of Mpesa. The content demonstrated here should be used for educational purposes only. Additionally, all views shared here are solely mine. What you will need: An active Azure subscription, get Azure for Student for free or get started with Azure for 12 months free. VS Code Basic knowledge in JavaScript (not a must) Access to Azure OpenAI, click here if you don't have access. Create a MongoDB account (You can also use Azure Cosmos DB vector store) Setting Up the Project In order to build this project, you will have to fork this repository and clone it. GitHub Repository link: https://github.com/tiprock-network/azure-qa-rag-mpesa . Follow the steps highlighted in the README.md to setup the project under Setting Up the Node.js Application. Create Resources that you Need In order to do this, you will need to have Azure CLI or Azure Developer CLI installed in your computer. Go ahead and follow the steps indicated in the README.md to create Azure resources under Azure Resources Set Up with Azure CLI. You might want to use Azure CLI to login in differently use a code. Here's how you can do this. Instead of using az login. You can do az login --use-code-device OR you would prefer using Azure Developer CLI and execute this command instead azd auth login --use-device-code Remember to update the .env file with the values you have used to name Azure OpenAI instance, Azure models and even the API Keys you have obtained while creating your resources. Setting Up MongoDB After accessing you MongoDB account get the URI link to your database and add it to the .env file along with your database name and vector store collection name you specified while creating your indexes for a vector search. Running the Project In order to run this Node.js project you will need to start the project using the following command. npm run dev The Vector Store The vector store used in this project is MongoDB store where the word embeddings were stored in MongoDB. From the embeddings model instance we created on Azure AI Foundry we are able to create embeddings that can be stored in a vector store. The following code below shows our embeddings model instance. //create new embedding model instance const azOpenEmbedding = new AzureOpenAIEmbeddings({ azureADTokenProvider, azureOpenAIApiInstanceName: process.env.AZURE_OPENAI_API_INSTANCE_NAME, azureOpenAIApiEmbeddingsDeploymentName: process.env.AZURE_OPENAI_API_DEPLOYMENT_EMBEDDING_NAME, azureOpenAIApiVersion: process.env.AZURE_OPENAI_API_VERSION, azureOpenAIBasePath: "https://eastus2.api.cognitive.microsoft.com/openai/deployments" }); The code in uploadDoc.js offers a simple way to do embeddings and store them to MongoDB. In this approach the text from the documents is loaded using the PDFLoader from Langchain community. The following code demonstrates how the embeddings are stored in the vector store. // Call the function and handle the result with await const storeToCosmosVectorStore = async () => { try { const documents = await returnSplittedContent() //create store instance const store = await MongoDBAtlasVectorSearch.fromDocuments( documents, azOpenEmbedding, { collection: vectorCollection, indexName: "myrag_index", textKey: "text", embeddingKey: "embedding", } ) if(!store){ console.log('Something wrong happened while creating store or getting store!') return false } console.log('Done creating/getting and uploading to store.') return true } catch (e) { console.log(`This error occurred: ${e}`) return false } } In this setup, Question Answering (QA) is achieved by integrating Azure OpenAI’s GPT-4o with MongoDB Vector Search through LangChain.js. The system processes user queries via an LLM (Large Language Model), which retrieves relevant information from a vectorized database, ensuring contextual and accurate responses. Azure OpenAI Embeddings convert text into dense vector representations, enabling semantic search within MongoDB. The LangChain RunnableSequence structures the retrieval and response generation workflow, while the StringOutputParser ensures proper text formatting. The most relevant code snippets to include are: AzureChatOpenAI instantiation, MongoDB connection setup, and the API endpoint handling QA queries using vector search and embeddings. There are some code snippets below to explain major parts of the code. Azure AI Chat Completion Model This is the model used in this implementation of RAG, where we use it as the model for chat completion. Below is a code snippet for it. const llm = new AzureChatOpenAI({ azTokenProvider, azureOpenAIApiInstanceName: process.env.AZURE_OPENAI_API_INSTANCE_NAME, azureOpenAIApiDeploymentName: process.env.AZURE_OPENAI_API_DEPLOYMENT_NAME, azureOpenAIApiVersion: process.env.AZURE_OPENAI_API_VERSION }) Using a Runnable Sequence to give out Chat Output This shows how a runnable sequence can be used to give out a response given the particular output format/ output parser added on to the chain. //Stream response app.post(`${process.env.BASE_URL}/az-openai/runnable-sequence/stream/chat`, async (req,res) => { //check for human message const { chatMsg } = req.body if(!chatMsg) return res.status(201).json({ message:'Hey, you didn\'t send anything.' }) //put the code in an error-handler try{ //create a prompt template format template const prompt = ChatPromptTemplate.fromMessages( [ ["system", `You are a French-to-English translator that detects if a message isn't in French. If it's not, you respond, "This is not French." Otherwise, you translate it to English.`], ["human", `${chatMsg}`] ] ) //runnable chain const chain = RunnableSequence.from([prompt, llm, outPutParser]) //chain result let result_stream = await chain.stream() //set response headers res.setHeader('Content-Type','application/json') res.setHeader('Transfer-Encoding','chunked') //create readable stream const readable = Readable.from(result_stream) res.status(201).write(`{"message": "Successful translation.", "response": "`); readable.on('data', (chunk) => { // Convert chunk to string and write it res.write(`${chunk}`); }); readable.on('end', () => { // Close the JSON response properly res.write('" }'); res.end(); }); readable.on('error', (err) => { console.error("Stream error:", err); res.status(500).json({ message: "Translation failed.", error: err.message }); }); }catch(e){ //deliver a 500 error response return res.status(500).json( { message:'Failed to send request.', error:e } ) } }) To run the front end of the code, go to your BASE_URL with the port given. This enables you to run the chatbot above and achieve similar results. The chatbot is basically HTML+CSS+JS. Where JavaScript is mainly used with fetch API to get a response. Thanks for reading. I hope you play around with the code and learn some new things. Additional Reads Introduction to LangChain.js Create an FAQ Bot on Azure Build a basic chat app in Python using Azure AI Foundry SDK
