Firebase Checkpoint Saver

examples/package.json

@@ -8,7 +8,7 @@
   "devDependencies": {
     "@langchain/anthropic": "^0.3.5",
     "@langchain/community": "^0.3.9",
-    "@langchain/core": "^0.3.16",
+    "@langchain/core": "^0.3.19",
     "@langchain/groq": "^0.1.2",
     "@langchain/langgraph": "workspace:*",
     "@langchain/mistralai": "^0.1.1",

libs/checkpoint-firebase/.env.example

@@ -0,0 +1,6 @@
+# ------------------LangSmith tracing------------------
+LANGCHAIN_TRACING_V2=true
+LANGCHAIN_ENDPOINT="https://api.smith.langchain.com"
+LANGCHAIN_API_KEY=
+LANGCHAIN_PROJECT=
+# -----------------------------------------------------

libs/checkpoint-firebase/.eslintrc.cjs

@@ -0,0 +1,69 @@
+module.exports = {
+  extends: [
+    "airbnb-base",
+    "eslint:recommended",
+    "prettier",
+    "plugin:@typescript-eslint/recommended",
+  ],
+  parserOptions: {
+    ecmaVersion: 12,
+    parser: "@typescript-eslint/parser",
+    project: "./tsconfig.json",
+    sourceType: "module",
+  },
+  plugins: ["@typescript-eslint", "no-instanceof", "eslint-plugin-jest"],
+  ignorePatterns: [
+    ".eslintrc.cjs",
+    "scripts",
+    "node_modules",
+    "dist",
+    "dist-cjs",
+    "*.js",
+    "*.cjs",
+    "*.d.ts",
+  ],
+  rules: {
+    "no-process-env": 2,
+    "no-instanceof/no-instanceof": 2,
+    "@typescript-eslint/explicit-module-boundary-types": 0,
+    "@typescript-eslint/no-empty-function": 0,
+    "@typescript-eslint/no-shadow": 0,
+    "@typescript-eslint/no-empty-interface": 0,
+    "@typescript-eslint/no-use-before-define": ["error", "nofunc"],
+    "@typescript-eslint/no-unused-vars": ["warn", { args: "none" }],
+    "@typescript-eslint/no-floating-promises": "error",
+    "@typescript-eslint/no-misused-promises": "error",
+    "arrow-body-style": 0,
+    camelcase: 0,
+    "class-methods-use-this": 0,
+    "import/extensions": [2, "ignorePackages"],
+    "import/no-extraneous-dependencies": [
+      "error",
+      { devDependencies: ["**/*.test.ts"] },
+    ],
+    "import/no-unresolved": 0,
+    "import/prefer-default-export": 0,
+    'jest/no-focused-tests': 'error',
+    "keyword-spacing": "error",
+    "max-classes-per-file": 0,
+    "max-len": 0,
+    "no-await-in-loop": 0,
+    "no-bitwise": 0,
+    "no-console": 0,
+    "no-empty-function": 0,
+    "no-restricted-syntax": 0,
+    "no-shadow": 0,
+    "no-continue": 0,
+    "no-void": 0,
+    "no-underscore-dangle": 0,
+    "no-use-before-define": 0,
+    "no-useless-constructor": 0,
+    "no-return-await": 0,
+    "consistent-return": 0,
+    "no-else-return": 0,
+    "func-names": 0,
+    "no-lonely-if": 0,
+    "prefer-rest-params": 0,
+    "new-cap": ["error", { properties: false, capIsNew: false }],
+  },
+};

libs/checkpoint-firebase/.gitignore

@@ -0,0 +1,7 @@
+index.cjs
+index.js
+index.d.ts
+index.d.cts
+node_modules
+dist
+.yarn

libs/checkpoint-firebase/.prettierrc

@@ -0,0 +1,19 @@
+{
+  "$schema": "https://json.schemastore.org/prettierrc",
+  "printWidth": 80,
+  "tabWidth": 2,
+  "useTabs": false,
+  "semi": true,
+  "singleQuote": false,
+  "quoteProps": "as-needed",
+  "jsxSingleQuote": false,
+  "trailingComma": "es5",
+  "bracketSpacing": true,
+  "arrowParens": "always",
+  "requirePragma": false,
+  "insertPragma": false,
+  "proseWrap": "preserve",
+  "htmlWhitespaceSensitivity": "css",
+  "vueIndentScriptAndStyle": false,
+  "endOfLine": "lf"
+}

libs/checkpoint-firebase/.release-it.json

@@ -0,0 +1,13 @@
+{
+  "github": {
+    "release": true,
+    "autoGenerate": true,
+    "tokenRef": "GITHUB_TOKEN_RELEASE"
+  },
+  "npm": {
+    "publish": true,
+    "versionArgs": [
+      "--workspaces-update=false"
+    ]
+  }
+}

libs/checkpoint-firebase/LICENSE

@@ -0,0 +1,21 @@
+The MIT License
+
+Copyright (c) 2024 LangChain
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

libs/checkpoint-firebase/README.md

@@ -0,0 +1,109 @@
+# @langchain/langgraph-checkpoint-firebase
+
+Implementation of a [LangGraph.js](https://github.com/langchain-ai/langgraphjs) CheckpointSaver that uses a FireBase instance.
+
+The `FirebaseSaver` class is an implementation of the `BaseCheckpointSaver` interface that uses Firebase Realtime Database for persistence. It is part of the `@langchain/langgraph-checkpoint` library and provides scalable, real-time management of checkpoints in LangGraph.js.
+
+---
+
+## Features
+
+- **Firebase Persistence**: Leverages Firebase's real-time capabilities to store checkpoints and metadata.
+- **Thread Management**: Isolates states using thread-based checkpointing for multi-tenant or parallel use cases.
+- **Pending Writes**: Handles intermediate writes for partially executed graph nodes.
+- **Real-Time Updates**: Takes advantage of Firebase's dynamic data updates for live applications.
+
+---
+
+## Installation
+
+### Prerequisites
+- Firebase Realtime Database instance
+- Node.js with TypeScript
+
+### Install Dependencies
+```bash
+npm install @langchain/langgraph-checkpoint firebase
+
+### Usage
+
+```ts
+import { initializeApp } from "firebase/app";
+import { getDatabase } from "firebase/database";
+import { FirebaseSaver } from "@langchain/langgraph-checkpoint-firebase";
+
+const writeConfig = {
+  configurable: {
+    thread_id: "1",
+    checkpoint_ns: ""
+  }
+};
+const readConfig = {
+  configurable: {
+    thread_id: "1"
+  }
+};
+
+const writeConfig = {
+  configurable: {
+    thread_id: "1",
+    checkpoint_ns: ""
+  }
+};
+const readConfig = {
+  configurable: {
+    thread_id: "1"
+  }
+};
+
+const firebaseConfig = {
+      apiKey: "REPLACE-WITH-YOUR-API-KEY",
+      authDomain: "REPLACE-WITH-YOUR-localhost",
+      projectId: "REPLACE-WITH-YOUR-TEST-PROJECT",
+      databaseURL: process.env.FIREBASEURL || "http://localhost:9000", // Use emulator URL
+    };
+    process.env.FIREBASE_URL = process.env.FIREBASEURL || "http://localhost:9000"
+    const app = initializeApp(firebaseConfig);
+
+    database = getDatabase(app);
+
+const checkpoint = {
+  v: 1,
+  ts: "2024-07-31T20:14:19.804150+00:00",
+  id: "1ef4f797-8335-6428-8001-8a1503f9b875",
+  channel_values: {
+    my_key: "meow",
+    node: "node"
+  },
+  channel_versions: {
+    __start__: 2,
+    my_key: 3,
+    start:node: 3,
+    node: 3
+  },
+  versions_seen: {
+    __input__: {},
+    __start__: {
+      __start__: 1
+    },
+    node: {
+      start:node: 2
+    }
+  },
+  pending_sends: [],
+}
+
+// store checkpoint
+await checkpointer.put(writeConfig, checkpoint, {}, {});
+
+// load checkpoint
+await checkpointer.get(readConfig);
+
+// list checkpoints
+for await (const checkpoint of checkpointer.list(readConfig)) {
+  console.log(checkpoint);
+}
+
+await client.close();
+```
+

libs/checkpoint-firebase/jest.config.cjs

@@ -0,0 +1,20 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} */
+module.exports = {
+  preset: "ts-jest/presets/default-esm",
+  testEnvironment: "./jest.env.cjs",
+  modulePathIgnorePatterns: ["dist/"],
+  moduleNameMapper: {
+    "^(\\.{1,2}/.*)\\.js$": "$1",
+  },
+  transform: {
+    "^.+\\.tsx?$": ["@swc/jest"],
+  },
+  transformIgnorePatterns: [
+    "/node_modules/",
+    "\\.pnp\\.[^\\/]+$",
+    "./scripts/jest-setup-after-env.js",
+  ],
+  setupFiles: ["dotenv/config"],
+  testTimeout: 20_000,
+  passWithNoTests: true,
+};

libs/checkpoint-firebase/jest.env.cjs

@@ -0,0 +1,12 @@
+const { TestEnvironment } = require("jest-environment-node");
+
+class AdjustedTestEnvironmentToSupportFloat32Array extends TestEnvironment {
+  constructor(config, context) {
+    // Make `instanceof Float32Array` return true in tests
+    // to avoid https://github.com/xenova/transformers.js/issues/57 and https://github.com/jestjs/jest/issues/2549
+    super(config, context);
+    this.global.Float32Array = Float32Array;
+  }
+}
+
+module.exports = AdjustedTestEnvironmentToSupportFloat32Array;

libs/checkpoint-firebase/langchain.config.js

@@ -0,0 +1,21 @@
+import { resolve, dirname } from "node:path";
+import { fileURLToPath } from "node:url";
+
+/**
+ * @param {string} relativePath
+ * @returns {string}
+ */
+function abs(relativePath) {
+  return resolve(dirname(fileURLToPath(import.meta.url)), relativePath);
+}
+
+export const config = {
+  internals: [/node\:/, /@langchain\/core\//, /async_hooks/],
+  entrypoints: {
+    index: "index"
+  },
+  tsConfigPath: resolve("./tsconfig.json"),
+  cjsSource: "./dist-cjs",
+  cjsDestination: "./dist",
+  abs,
+};