Nc/fix tracer chat output (#1253)

* Use the same message format for output as used in input

* Move message conversion logic to toJSON method, which is called by JSON.stringify, this makes it harder for people to use LLMResult

* Fix imports

* Update tests

langchain/src/callbacks/handlers/tracer.ts

@@ -6,7 +6,6 @@ import {
   RunInputs,
   RunOutputs,
 } from "../../schema/index.js";
-import { mapChatMessagesToStoredMessages } from "../../stores/message/utils.js";
 import { BaseCallbackHandler } from "../base.js";
 
 export type RunType = "llm" | "chain" | "tool";
@@ -121,17 +120,14 @@ export abstract class BaseTracer extends BaseCallbackHandler {
     parentRunId?: string
   ): Promise<void> {
     const execution_order = this._getExecutionOrder(parentRunId);
-    const convertedMessages = messages.map((batch) =>
-      mapChatMessagesToStoredMessages(batch)
-    );
     const run: Run = {
       id: runId,
       name: llm.name,
       parent_run_id: parentRunId,
       start_time: Date.now(),
       end_time: 0,
       serialized: llm,
-      inputs: { messages: convertedMessages },
+      inputs: { messages },
       execution_order,
       child_runs: [],
       child_execution_order: execution_order,

langchain/src/callbacks/tests/tracer.test.ts

@@ -86,24 +86,43 @@ test("Test Chat Message Run", async () => {
   await tracer.handleLLMEnd({ generations: [] }, runId);
   expect(tracer.runs.length).toBe(1);
   const run = tracer.runs[0];
-  const compareRun: Run = {
-    id: runId,
-    name: "test",
-    start_time: _DATE,
-    end_time: _DATE,
-    execution_order: 1,
-    child_execution_order: 1,
-    serialized: { name: "test" },
-    inputs: {
-      messages: [
-        [{ type: "human", data: { content: "Avast", role: undefined } }],
-      ],
+  expect(run).toMatchInlineSnapshot(
+    {
+      id: expect.any(String),
     },
-    run_type: "llm",
-    outputs: { generations: [] },
-    child_runs: [],
-  };
-  expect(run).toEqual(compareRun);
+    `
+    {
+      "child_execution_order": 1,
+      "child_runs": [],
+      "end_time": 1620000000000,
+      "execution_order": 1,
+      "id": Any<String>,
+      "inputs": {
+        "messages": [
+          [
+            {
+              "data": {
+                "content": "Avast",
+                "role": undefined,
+              },
+              "type": "human",
+            },
+          ],
+        ],
+      },
+      "name": "test",
+      "outputs": {
+        "generations": [],
+      },
+      "parent_run_id": undefined,
+      "run_type": "llm",
+      "serialized": {
+        "name": "test",
+      },
+      "start_time": 1620000000000,
+    }
+  `
+  );
 });
 
 test("Test LLM Run no start", async () => {

langchain/src/client/langchainplus.ts

@@ -5,15 +5,13 @@ import {
   LLMResult,
   RunInputs,
   RunOutputs,
+  StoredMessage,
 } from "../schema/index.js";
 import { BaseLanguageModel } from "../base_language/index.js";
 import { BaseChain } from "../chains/base.js";
 import { BaseLLM } from "../llms/base.js";
 import { BaseChatModel } from "../chat_models/base.js";
-import {
-  StoredMessage,
-  mapStoredMessagesToChatMessages,
-} from "../stores/message/utils.js";
+import { mapStoredMessagesToChatMessages } from "../stores/message/utils.js";
 
 export interface RunResult extends BaseRun {
   name: string;

langchain/src/prompts/tests/chat.test.ts

@@ -222,7 +222,7 @@ test("Test using partial", async () => {
   // partial prompt has only remaining variables
   expect(partialPrompt.inputVariables).toEqual(["bar"]);
 
-  expect(await partialPrompt.format({ bar: "baz" })).toBe(
-    '[{"text":"foobaz"}]'
+  expect(await partialPrompt.format({ bar: "baz" })).toMatchInlineSnapshot(
+    `"[{"type":"human","data":{"content":"foobaz"}}]"`
   );
 });

langchain/src/schema/index.ts

@@ -47,6 +47,19 @@ export type LLMResult = {
   // eslint-disable-next-line @typescript-eslint/no-explicit-any
   [RUN_KEY]?: Record<string, any>;
 };
+
+export interface StoredMessageData {
+  content: string;
+  role: string | undefined;
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  additional_kwargs?: Record<string, any>;
+}
+
+export interface StoredMessage {
+  type: string;
+  data: StoredMessageData;
+}
+
 export type MessageType = "human" | "ai" | "generic" | "system";
 
 export abstract class BaseChatMessage {
@@ -62,6 +75,16 @@ export abstract class BaseChatMessage {
   constructor(text: string) {
     this.text = text;
   }
+
+  toJSON(): StoredMessage {
+    return {
+      type: this._getType(),
+      data: {
+        content: this.text,
+        role: "role" in this ? (this.role as string) : undefined,
+      },
+    };
+  }
 }
 
 export class HumanChatMessage extends BaseChatMessage {

langchain/src/stores/message/dynamodb.ts

@@ -11,11 +11,11 @@ import {
 } from "@aws-sdk/client-dynamodb";
 
 import {
+  StoredMessage,
   BaseChatMessage,
   BaseListChatMessageHistory,
 } from "../../schema/index.js";
 import {
-  StoredMessage,
   mapChatMessagesToStoredMessages,
   mapStoredMessagesToChatMessages,
 } from "./utils.js";

langchain/src/stores/message/redis.ts

@@ -7,11 +7,11 @@ import {
   RedisScripts,
 } from "redis";
 import {
+  StoredMessage,
   BaseChatMessage,
   BaseListChatMessageHistory,
 } from "../../schema/index.js";
 import {
-  StoredMessage,
   mapChatMessagesToStoredMessages,
   mapStoredMessagesToChatMessages,
 } from "./utils.js";

langchain/src/stores/message/utils.ts

@@ -3,22 +3,10 @@ import {
   BaseChatMessage,
   ChatMessage,
   HumanChatMessage,
+  StoredMessage,
   SystemChatMessage,
 } from "../../schema/index.js";
 
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
-export type AdditionalKwargs = Record<string, any>;
-export interface StoredMessageData {
-  content: string;
-  role: string | undefined;
-  additional_kwargs?: AdditionalKwargs;
-}
-
-export interface StoredMessage {
-  type: string;
-  data: StoredMessageData;
-}
-
 interface StoredMessageV1 {
   type: string;
   role: string | undefined;
@@ -72,11 +60,5 @@ export function mapStoredMessagesToChatMessages(
 export function mapChatMessagesToStoredMessages(
   messages: BaseChatMessage[]
 ): StoredMessage[] {
-  return messages.map((message) => ({
-    type: message._getType(),
-    data: {
-      content: message.text,
-      role: "role" in message ? (message.role as string) : undefined,
-    },
-  }));
+  return messages.map((message) => message.toJSON());
 }