agsamantha/node_modules/langchain/dist/chains/llm_chain.cjs

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2024-10-02 15:15:21 -05:00
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.LLMChain = void 0;
const base_1 = require("@langchain/core/language_models/base");
const prompts_1 = require("@langchain/core/prompts");
const runnables_1 = require("@langchain/core/runnables");
const base_js_1 = require("./base.cjs");
const noop_js_1 = require("../output_parsers/noop.cjs");
function isBaseLanguageModel(llmLike) {
return typeof llmLike._llmType === "function";
}
function _getLanguageModel(llmLike) {
if (isBaseLanguageModel(llmLike)) {
return llmLike;
}
else if ("bound" in llmLike && runnables_1.Runnable.isRunnable(llmLike.bound)) {
return _getLanguageModel(llmLike.bound);
}
else if ("runnable" in llmLike &&
"fallbacks" in llmLike &&
runnables_1.Runnable.isRunnable(llmLike.runnable)) {
return _getLanguageModel(llmLike.runnable);
}
else if ("default" in llmLike && runnables_1.Runnable.isRunnable(llmLike.default)) {
return _getLanguageModel(llmLike.default);
}
else {
throw new Error("Unable to extract BaseLanguageModel from llmLike object.");
}
}
/**
* @deprecated This class will be removed in 1.0.0. Use the LangChain Expression Language (LCEL) instead.
* See the example below for how to use LCEL with the LLMChain class:
*
* Chain to run queries against LLMs.
*
* @example
* ```ts
* import { ChatPromptTemplate } from "@langchain/core/prompts";
* import { ChatOpenAI } from "@langchain/openai";
*
* const prompt = ChatPromptTemplate.fromTemplate("Tell me a {adjective} joke");
* const llm = new ChatOpenAI();
* const chain = prompt.pipe(llm);
*
* const response = await chain.invoke({ adjective: "funny" });
* ```
*/
class LLMChain extends base_js_1.BaseChain {
static lc_name() {
return "LLMChain";
}
get inputKeys() {
return this.prompt.inputVariables;
}
get outputKeys() {
return [this.outputKey];
}
constructor(fields) {
super(fields);
Object.defineProperty(this, "lc_serializable", {
enumerable: true,
configurable: true,
writable: true,
value: true
});
Object.defineProperty(this, "prompt", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
Object.defineProperty(this, "llm", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
Object.defineProperty(this, "llmKwargs", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
Object.defineProperty(this, "outputKey", {
enumerable: true,
configurable: true,
writable: true,
value: "text"
});
Object.defineProperty(this, "outputParser", {
enumerable: true,
configurable: true,
writable: true,
value: void 0
});
this.prompt = fields.prompt;
this.llm = fields.llm;
this.llmKwargs = fields.llmKwargs;
this.outputKey = fields.outputKey ?? this.outputKey;
this.outputParser =
fields.outputParser ?? new noop_js_1.NoOpOutputParser();
if (this.prompt.outputParser) {
if (fields.outputParser) {
throw new Error("Cannot set both outputParser and prompt.outputParser");
}
this.outputParser = this.prompt.outputParser;
}
}
getCallKeys() {
const callKeys = "callKeys" in this.llm ? this.llm.callKeys : [];
return callKeys;
}
/** @ignore */
_selectMemoryInputs(values) {
const valuesForMemory = super._selectMemoryInputs(values);
const callKeys = this.getCallKeys();
for (const key of callKeys) {
if (key in values) {
delete valuesForMemory[key];
}
}
return valuesForMemory;
}
/** @ignore */
async _getFinalOutput(generations, promptValue, runManager) {
let finalCompletion;
if (this.outputParser) {
finalCompletion = await this.outputParser.parseResultWithPrompt(generations, promptValue, runManager?.getChild());
}
else {
finalCompletion = generations[0].text;
}
return finalCompletion;
}
/**
* Run the core logic of this chain and add to output if desired.
*
* Wraps _call and handles memory.
*/
call(values, config) {
return super.call(values, config);
}
/** @ignore */
async _call(values, runManager) {
const valuesForPrompt = { ...values };
const valuesForLLM = {
...this.llmKwargs,
};
const callKeys = this.getCallKeys();
for (const key of callKeys) {
if (key in values) {
if (valuesForLLM) {
valuesForLLM[key] =
values[key];
delete valuesForPrompt[key];
}
}
}
const promptValue = await this.prompt.formatPromptValue(valuesForPrompt);
if ("generatePrompt" in this.llm) {
const { generations } = await this.llm.generatePrompt([promptValue], valuesForLLM, runManager?.getChild());
return {
[this.outputKey]: await this._getFinalOutput(generations[0], promptValue, runManager),
};
}
const modelWithParser = this.outputParser
? this.llm.pipe(this.outputParser)
: this.llm;
const response = await modelWithParser.invoke(promptValue, runManager?.getChild());
return {
[this.outputKey]: response,
};
}
/**
* Format prompt with values and pass to LLM
*
* @param values - keys to pass to prompt template
* @param callbackManager - CallbackManager to use
* @returns Completion from LLM.
*
* @example
* ```ts
* llm.predict({ adjective: "funny" })
* ```
*/
async predict(values, callbackManager) {
const output = await this.call(values, callbackManager);
return output[this.outputKey];
}
_chainType() {
return "llm";
}
static async deserialize(data) {
const { llm, prompt } = data;
if (!llm) {
throw new Error("LLMChain must have llm");
}
if (!prompt) {
throw new Error("LLMChain must have prompt");
}
return new LLMChain({
llm: await base_1.BaseLanguageModel.deserialize(llm),
prompt: await prompts_1.BasePromptTemplate.deserialize(prompt),
});
}
/** @deprecated */
serialize() {
const serialize = "serialize" in this.llm ? this.llm.serialize() : undefined;
return {
_type: `${this._chainType()}_chain`,
llm: serialize,
prompt: this.prompt.serialize(),
};
}
_getNumTokens(text) {
return _getLanguageModel(this.llm).getNumTokens(text);
}
}
exports.LLMChain = LLMChain;