LangChain Integration

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import { OpikCallbackHandler } from "opik-langchain";
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import { ChatOpenAI } from "@langchain/openai";
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// Create the Opik callback handler
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const opikHandler = new OpikCallbackHandler();
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// Option 1: Add the handler at model initialization time
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const llm = new ChatOpenAI({
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  callbacks: [opikHandler], // Will be used for all calls to this model
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});
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// Run LLM
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const response = await llm.invoke("Hello, how can you help me today?");
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// Option 2: Add the handler at invocation time (or both)
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const llmWithoutHandler = new ChatOpenAI();
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const response2 = await llmWithoutHandler.invoke("What's the weather like today?", {
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  callbacks: [opikHandler], // Will be used just for this specific call
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});
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// You can also combine both approaches
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const anotherResponse = await llm.invoke("Tell me a joke", {
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  callbacks: [opikHandler], // Will use both the constructor handler and this one
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});
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// Ensure all traces are sent before your app terminates
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await opikHandler.flushAsync();

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import { OpikCallbackHandler } from "opik-langchain";
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import { ChatOpenAI } from "@langchain/openai";
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import { PromptTemplate } from "@langchain/core/prompts";
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import { LLMChain } from "langchain/chains";
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import { setGlobalCallbacks } from "@langchain/core/callbacks/manager";
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// Create the Opik callback handler
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const opikHandler = new OpikCallbackHandler({
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  tags: ["global"],
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  projectName: "langchain-app",
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});
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// Set as global handler (will be used for all LangChain components)
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setGlobalCallbacks([opikHandler]);
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// These components will now automatically use the global handler
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const llm = new ChatOpenAI();
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const template = PromptTemplate.fromTemplate("Answer this question: {question}");
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const chain = new LLMChain({ llm, prompt: template });
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// Global handlers are used automatically
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const result = await chain.call({ question: "What is 2+2?" });
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// Flush before your app exits
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await opikHandler.flushAsync();

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const opikHandler = new OpikCallbackHandler({
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  // Optional array of tags to apply to all traces
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  tags: ["langchain", "production", "user-query"],
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  // Optional metadata to include with all traces
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  metadata: {
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    environment: "production",
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    version: "1.0.0",
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  },
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  // Optional project name for Opik
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  projectName: "my-langchain-project",
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  // Optional pre-configured Opik client
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  // If not provided, a new client will be created automatically
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  client: customOpikClient,
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});