@langchain/core
Version:
Core LangChain.js abstractions and schemas
190 lines (189 loc) • 8.13 kB
JavaScript
;
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
var desc = Object.getOwnPropertyDescriptor(m, k);
if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
desc = { enumerable: true, get: function() { return m[k]; } };
}
Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
if (k2 === undefined) k2 = k;
o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
o["default"] = v;
});
var __importStar = (this && this.__importStar) || function (mod) {
if (mod && mod.__esModule) return mod;
var result = {};
if (mod != null) for (var k in mod) if (k !== "default" && Object.prototype.hasOwnProperty.call(mod, k)) __createBinding(result, mod, k);
__setModuleDefault(result, mod);
return result;
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.load = void 0;
const serializable_js_1 = require("./serializable.cjs");
const import_constants_js_1 = require("./import_constants.cjs");
const coreImportMap = __importStar(require("./import_map.cjs"));
const map_keys_js_1 = require("./map_keys.cjs");
const env_js_1 = require("../utils/env.cjs");
function combineAliasesAndInvert(constructor) {
const aliases = {};
for (
// eslint-disable-next-line @typescript-eslint/no-this-alias
let current = constructor; current && current.prototype; current = Object.getPrototypeOf(current)) {
Object.assign(aliases, Reflect.get(current.prototype, "lc_aliases"));
}
return Object.entries(aliases).reduce((acc, [key, value]) => {
acc[value] = key;
return acc;
}, {});
}
async function reviver(value) {
const { optionalImportsMap = {}, optionalImportEntrypoints = [], importMap = {}, secretsMap = {}, path = ["$"], } = this;
const pathStr = path.join(".");
if (typeof value === "object" &&
value !== null &&
!Array.isArray(value) &&
"lc" in value &&
"type" in value &&
"id" in value &&
value.lc === 1 &&
value.type === "secret") {
const serialized = value;
const [key] = serialized.id;
if (key in secretsMap) {
return secretsMap[key];
}
else {
const secretValueInEnv = (0, env_js_1.getEnvironmentVariable)(key);
if (secretValueInEnv) {
return secretValueInEnv;
}
else {
throw new Error(`Missing key "${key}" for ${pathStr} in load(secretsMap={})`);
}
}
}
else if (typeof value === "object" &&
value !== null &&
!Array.isArray(value) &&
"lc" in value &&
"type" in value &&
"id" in value &&
value.lc === 1 &&
value.type === "not_implemented") {
const serialized = value;
const str = JSON.stringify(serialized);
throw new Error(`Trying to load an object that doesn't implement serialization: ${pathStr} -> ${str}`);
}
else if (typeof value === "object" &&
value !== null &&
!Array.isArray(value) &&
"lc" in value &&
"type" in value &&
"id" in value &&
"kwargs" in value &&
value.lc === 1) {
const serialized = value;
const str = JSON.stringify(serialized);
const [name, ...namespaceReverse] = serialized.id.slice().reverse();
const namespace = namespaceReverse.reverse();
const importMaps = { langchain_core: coreImportMap, langchain: importMap };
let module = null;
const optionalImportNamespaceAliases = [namespace.join("/")];
if (namespace[0] === "langchain_community") {
optionalImportNamespaceAliases.push(["langchain", ...namespace.slice(1)].join("/"));
}
const matchingNamespaceAlias = optionalImportNamespaceAliases.find((alias) => alias in optionalImportsMap);
if (import_constants_js_1.optionalImportEntrypoints
.concat(optionalImportEntrypoints)
.includes(namespace.join("/")) ||
matchingNamespaceAlias) {
if (matchingNamespaceAlias !== undefined) {
module = await optionalImportsMap[matchingNamespaceAlias];
}
else {
throw new Error(`Missing key "${namespace.join("/")}" for ${pathStr} in load(optionalImportsMap={})`);
}
}
else {
let finalImportMap;
// Currently, we only support langchain and langchain_core imports.
if (namespace[0] === "langchain" || namespace[0] === "langchain_core") {
finalImportMap = importMaps[namespace[0]];
namespace.shift();
}
else {
throw new Error(`Invalid namespace: ${pathStr} -> ${str}`);
}
// The root namespace "langchain" is not a valid import.
if (namespace.length === 0) {
throw new Error(`Invalid namespace: ${pathStr} -> ${str}`);
}
// Find the longest matching namespace.
let importMapKey;
do {
importMapKey = namespace.join("__");
if (importMapKey in finalImportMap) {
break;
}
else {
namespace.pop();
}
} while (namespace.length > 0);
// If no matching namespace is found, throw an error.
if (importMapKey in finalImportMap) {
module = finalImportMap[importMapKey];
}
}
if (typeof module !== "object" || module === null) {
throw new Error(`Invalid namespace: ${pathStr} -> ${str}`);
}
// Extract the builder from the import map.
const builder =
// look for a named export with the same name as the class
module[name] ??
// look for an export with a lc_name property matching the class name
// this is necessary for classes that are minified
Object.values(module).find((v) => typeof v === "function" &&
(0, serializable_js_1.get_lc_unique_name)(v) === name);
if (typeof builder !== "function") {
throw new Error(`Invalid identifer: ${pathStr} -> ${str}`);
}
// Recurse on the arguments, which may be serialized objects themselves
const kwargs = await reviver.call({ ...this, path: [...path, "kwargs"] }, serialized.kwargs);
// Construct the object
if (serialized.type === "constructor") {
// eslint-disable-next-line new-cap, @typescript-eslint/no-explicit-any
const instance = new builder((0, map_keys_js_1.mapKeys)(kwargs, map_keys_js_1.keyFromJson, combineAliasesAndInvert(builder)));
// Minification in severless/edge runtimes will mange the
// name of classes presented in traces. As the names in import map
// are present as-is even with minification, use these names instead
Object.defineProperty(instance.constructor, "name", { value: name });
return instance;
}
else {
throw new Error(`Invalid type: ${pathStr} -> ${str}`);
}
}
else if (typeof value === "object" && value !== null) {
if (Array.isArray(value)) {
return Promise.all(value.map((v, i) => reviver.call({ ...this, path: [...path, `${i}`] }, v)));
}
else {
return Object.fromEntries(await Promise.all(Object.entries(value).map(async ([key, value]) => [
key,
await reviver.call({ ...this, path: [...path, key] }, value),
])));
}
}
return value;
}
async function load(text, mappings) {
const json = JSON.parse(text);
return reviver.call({ ...mappings }, json);
}
exports.load = load;