fix: use getters to lazy load modules

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@literalai/client",
-  "version": "0.0.517",
+  "version": "0.0.518",
   "description": "",
   "exports": {
     ".": {

src/instrumentation/index.ts

@@ -19,75 +19,85 @@ export default (client: LiteralClient) => ({
    * @param options.metadata Metadata to attach to all generations.
    * @returns
    */
-  openai: (options?: OpenAIGlobalOptions) => {
-    try {
-      // eslint-disable-next-line @typescript-eslint/no-var-requires
-      const { default: instrumentOpenAI } = require('./openai');
-      return instrumentOpenAI(client, options);
-    } catch (error) {
-      throw new Error(
-        'Failed to load OpenAI. Please ensure openai is installed.'
-      );
-    }
-  },
-
-  langchain: {
-    literalCallback: (params?: {
-      threadId?: string;
-      chainTypesToIgnore?: string[];
-    }) => {
+  get openai() {
+    return (options?: OpenAIGlobalOptions) => {
       try {
         // eslint-disable-next-line @typescript-eslint/no-var-requires
-        const { LiteralCallbackHandler } = require('./langchain');
-        return new LiteralCallbackHandler(
-          client,
-          params?.threadId,
-          params?.chainTypesToIgnore
-        );
+        const { default: instrumentOpenAI } = require('./openai');
+        return instrumentOpenAI(client, options);
       } catch (error) {
         throw new Error(
-          'Failed to load langchain. Please ensure langchain is installed.'
+          'Failed to load OpenAI. Please ensure openai is installed.'
         );
       }
-    }
+    };
   },
 
-  vercel: {
-    instrument: <TFunction extends AllVercelFn>(fn: TFunction) => {
-      try {
-        // eslint-disable-next-line @typescript-eslint/no-var-requires
-        const { makeInstrumentVercelSDK } = require('./vercel-sdk');
-        return makeInstrumentVercelSDK(client)(fn);
-      } catch (error) {
-        throw new Error(
-          'Failed to load Vercel SDK. Please ensure @vercel/ai is installed.'
-        );
+  get langchain() {
+    return {
+      literalCallback: (params?: {
+        threadId?: string;
+        chainTypesToIgnore?: string[];
+      }) => {
+        try {
+          // eslint-disable-next-line @typescript-eslint/no-var-requires
+          const { LiteralCallbackHandler } = require('./langchain');
+          return new LiteralCallbackHandler(
+            client,
+            params?.threadId,
+            params?.chainTypesToIgnore
+          );
+        } catch (error) {
+          throw new Error(
+            'Failed to load langchain. Please ensure langchain is installed.'
+          );
+        }
       }
-    }
+    };
   },
 
-  llamaIndex: {
-    instrument: () => {
-      try {
-        // eslint-disable-next-line @typescript-eslint/no-var-requires
-        const { instrumentLlamaIndex } = require('./llamaindex');
-        return instrumentLlamaIndex(client);
-      } catch (error) {
-        throw new Error(
-          'Failed to load LlamaIndex. Please ensure llamaindex is installed.'
-        );
+  get vercel() {
+    return {
+      instrument: <TFunction extends AllVercelFn>(fn: TFunction) => {
+        try {
+          // eslint-disable-next-line @typescript-eslint/no-var-requires
+          const { makeInstrumentVercelSDK } = require('./vercel-sdk');
+          return makeInstrumentVercelSDK(client)(fn);
+        } catch (error) {
+          throw new Error(
+            'Failed to load Vercel SDK. Please ensure @vercel/ai is installed.'
+          );
+        }
       }
+    };
+  },
+
+  llamaIndex: {
+    get instrument() {
+      return () => {
+        try {
+          // eslint-disable-next-line @typescript-eslint/no-var-requires
+          const { instrumentLlamaIndex } = require('./llamaindex');
+          return instrumentLlamaIndex(client);
+        } catch (error) {
+          throw new Error(
+            'Failed to load LlamaIndex. Please ensure llamaindex is installed.'
+          );
+        }
+      };
     },
-    withThread: <R>(thread: Thread, callback: () => R) => {
-      try {
-        // eslint-disable-next-line @typescript-eslint/no-var-requires
-        const { withThread } = require('./llamaindex');
-        return withThread(thread, callback);
-      } catch (error) {
-        throw new Error(
-          'Failed to load LlamaIndex. Please ensure llamaindex is installed.'
-        );
-      }
+    get withThread() {
+      return <R>(thread: Thread, callback: () => R) => {
+        try {
+          // eslint-disable-next-line @typescript-eslint/no-var-requires
+          const { withThread } = require('./llamaindex');
+          return withThread(thread, callback);
+        } catch (error) {
+          throw new Error(
+            'Failed to load LlamaIndex. Please ensure llamaindex is installed.'
+          );
+        }
+      };
     }
   }
 });

src/prompt-engineering/prompt.ts

@@ -6,7 +6,6 @@ import {
 
 import { API } from '../api';
 import { DatasetItem } from '../evaluation/dataset';
-import { CustomChatPromptTemplate } from '../instrumentation/langchain';
 import {
   GenerationType,
   IGenerationMessage
@@ -133,6 +132,10 @@ export class Prompt extends PromptFields {
    * @returns A custom chat prompt template configured with the prompt's data.
    */
   toLangchainChatPromptTemplate() {
+    const {
+      CustomChatPromptTemplate
+      // eslint-disable-next-line @typescript-eslint/no-var-requires
+    } = require('../instrumentation/langchain');
     const lcMessages: [string, string][] = this.templateMessages.map((m) => [
       m.role,
       m.content as string