{"version":3,"file":"summary_buffer.cjs","names":["BaseConversationSummaryMemory","getBufferString"],"sources":["../../src/memory/summary_buffer.ts"],"sourcesContent":["import { getBufferString } from \"@langchain/core/messages\";\nimport {\n InputValues,\n MemoryVariables,\n OutputValues,\n} from \"@langchain/core/memory\";\nimport {\n BaseConversationSummaryMemory,\n BaseConversationSummaryMemoryInput,\n} from \"./summary.js\";\n\n/**\n * Interface for the input parameters of the\n * ConversationSummaryBufferMemory class.\n */\nexport interface ConversationSummaryBufferMemoryInput extends BaseConversationSummaryMemoryInput {\n maxTokenLimit?: number;\n}\n\n/**\n * Class that extends BaseConversationSummaryMemory and implements\n * ConversationSummaryBufferMemoryInput. It manages the conversation\n * history in a LangChain application by maintaining a buffer of chat\n * messages and providing methods to load, save, prune, and clear the\n * memory.\n * @example\n * ```typescript\n * // Initialize the memory with a specific model and token limit\n * const memory = new ConversationSummaryBufferMemory({\n * llm: new ChatOpenAI({ model: \"gpt-3.5-turbo-instruct\", temperature: 0 }),\n * maxTokenLimit: 10,\n * });\n *\n * // Save conversation context to memory\n * await memory.saveContext({ input: \"hi\" }, { output: \"whats up\" });\n * await memory.saveContext({ input: \"not much you\" }, { output: \"not much\" });\n *\n * // Load the conversation history from memory\n * const history = await memory.loadMemoryVariables({});\n * console.log({ history });\n *\n * // Create a chat prompt using the conversation history\n * const chatPrompt = ChatPromptTemplate.fromMessages([\n * SystemMessagePromptTemplate.fromTemplate(\n * \"The following is a friendly conversation between a human and an AI. The AI is talkative and provides lots of specific details from its context. If the AI does not know the answer to a question, it truthfully says it does not know.\",\n * ),\n * new MessagesPlaceholder(\"history\"),\n * HumanMessagePromptTemplate.fromTemplate(\"{input}\"),\n * ]);\n *\n * // Initialize the conversation chain with the model, memory, and prompt\n * const chain = new ConversationChain({\n * llm: new ChatOpenAI({ model: \"gpt-4o-mini\", temperature: 0.9, verbose: true }),\n * memory: memory,\n * prompt: chatPrompt,\n * });\n * ```\n */\nexport class ConversationSummaryBufferMemory\n extends BaseConversationSummaryMemory\n implements ConversationSummaryBufferMemoryInput\n{\n movingSummaryBuffer = \"\";\n\n maxTokenLimit = 2000;\n\n constructor(fields: ConversationSummaryBufferMemoryInput) {\n super(fields);\n\n this.maxTokenLimit = fields?.maxTokenLimit ?? this.maxTokenLimit;\n }\n\n get memoryKeys() {\n return [this.memoryKey];\n }\n\n /**\n * Method that loads the chat messages from the memory and returns them as\n * a string or as a list of messages, depending on the returnMessages\n * property.\n * @param _ InputValues object, not used in this method.\n * @returns Promise that resolves with MemoryVariables object containing the loaded chat messages.\n */\n async loadMemoryVariables(_?: InputValues): Promise {\n let buffer = await this.chatHistory.getMessages();\n if (this.movingSummaryBuffer) {\n buffer = [\n new this.summaryChatMessageClass(this.movingSummaryBuffer),\n ...buffer,\n ];\n }\n\n let finalBuffer;\n if (this.returnMessages) {\n finalBuffer = buffer;\n } else {\n finalBuffer = getBufferString(buffer, this.humanPrefix, this.aiPrefix);\n }\n\n return { [this.memoryKey]: finalBuffer };\n }\n\n /**\n * Method that saves the context of the conversation, including the input\n * and output values, and prunes the memory if it exceeds the maximum\n * token limit.\n * @param inputValues InputValues object containing the input values of the conversation.\n * @param outputValues OutputValues object containing the output values of the conversation.\n * @returns Promise that resolves when the context is saved and the memory is pruned.\n */\n async saveContext(\n inputValues: InputValues,\n outputValues: OutputValues\n ): Promise {\n await super.saveContext(inputValues, outputValues);\n await this.prune();\n }\n\n /**\n * Method that prunes the memory if the total number of tokens in the\n * buffer exceeds the maxTokenLimit. It removes messages from the\n * beginning of the buffer until the total number of tokens is within the\n * limit.\n * @returns Promise that resolves when the memory is pruned.\n */\n async prune() {\n // Prune buffer if it exceeds max token limit\n let buffer = await this.chatHistory.getMessages();\n if (this.movingSummaryBuffer) {\n buffer = [\n new this.summaryChatMessageClass(this.movingSummaryBuffer),\n ...buffer,\n ];\n }\n\n let currBufferLength = await this.llm.getNumTokens(\n getBufferString(buffer, this.humanPrefix, this.aiPrefix)\n );\n\n if (currBufferLength > this.maxTokenLimit) {\n const prunedMemory = [];\n while (currBufferLength > this.maxTokenLimit) {\n const poppedMessage = buffer.shift();\n if (poppedMessage) {\n prunedMemory.push(poppedMessage);\n currBufferLength = await this.llm.getNumTokens(\n getBufferString(buffer, this.humanPrefix, this.aiPrefix)\n );\n }\n }\n this.movingSummaryBuffer = await this.predictNewSummary(\n prunedMemory,\n this.movingSummaryBuffer\n );\n }\n }\n\n /**\n * Method that clears the memory and resets the movingSummaryBuffer.\n * @returns Promise that resolves when the memory is cleared.\n */\n async clear() {\n await super.clear();\n this.movingSummaryBuffer = \"\";\n }\n}\n"],"mappings":";;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;AA0DA,IAAa,kCAAb,cACUA,gBAAAA,8BAEV;CACE,sBAAsB;CAEtB,gBAAgB;CAEhB,YAAY,QAA8C;EACxD,MAAM,MAAM;EAEZ,KAAK,gBAAgB,QAAQ,iBAAiB,KAAK;CACrD;CAEA,IAAI,aAAa;EACf,OAAO,CAAC,KAAK,SAAS;CACxB;;;;;;;;CASA,MAAM,oBAAoB,GAA2C;EACnE,IAAI,SAAS,MAAM,KAAK,YAAY,YAAY;EAChD,IAAI,KAAK,qBACP,SAAS,CACP,IAAI,KAAK,wBAAwB,KAAK,mBAAmB,GACzD,GAAG,MACL;EAGF,IAAI;EACJ,IAAI,KAAK,gBACP,cAAc;OAEd,eAAA,GAAcC,yBAAAA,gBAAAA,CAAgB,QAAQ,KAAK,aAAa,KAAK,QAAQ;EAGvE,OAAO,GAAG,KAAK,YAAY,YAAY;CACzC;;;;;;;;;CAUA,MAAM,YACJ,aACA,cACe;EACf,MAAM,MAAM,YAAY,aAAa,YAAY;EACjD,MAAM,KAAK,MAAM;CACnB;;;;;;;;CASA,MAAM,QAAQ;EAEZ,IAAI,SAAS,MAAM,KAAK,YAAY,YAAY;EAChD,IAAI,KAAK,qBACP,SAAS,CACP,IAAI,KAAK,wBAAwB,KAAK,mBAAmB,GACzD,GAAG,MACL;EAGF,IAAI,mBAAmB,MAAM,KAAK,IAAI,cAAA,GACpCA,yBAAAA,gBAAAA,CAAgB,QAAQ,KAAK,aAAa,KAAK,QAAQ,CACzD;EAEA,IAAI,mBAAmB,KAAK,eAAe;GACzC,MAAM,eAAe,CAAC;GACtB,OAAO,mBAAmB,KAAK,eAAe;IAC5C,MAAM,gBAAgB,OAAO,MAAM;IACnC,IAAI,eAAe;KACjB,aAAa,KAAK,aAAa;KAC/B,mBAAmB,MAAM,KAAK,IAAI,cAAA,GAChCA,yBAAAA,gBAAAA,CAAgB,QAAQ,KAAK,aAAa,KAAK,QAAQ,CACzD;IACF;GACF;GACA,KAAK,sBAAsB,MAAM,KAAK,kBACpC,cACA,KAAK,mBACP;EACF;CACF;;;;;CAMA,MAAM,QAAQ;EACZ,MAAM,MAAM,MAAM;EAClB,KAAK,sBAAsB;CAC7B;AACF"}