chore: enable linting for langgraph-api

libs/langgraph-api/.eslintrc.cjs

@@ -0,0 +1,68 @@
+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"],
+  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,
+    "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/langgraph-api/package.json

@@ -42,6 +42,10 @@
     "build": "yarn turbo:command build:internal --filter=@langchain/langgraph-api",
     "build:internal": "yarn clean && node scripts/build.mjs",
     "dev": "tsx ./tests/utils.server.mts --dev",
+    "lint:eslint": "NODE_OPTIONS=--max-old-space-size=4096 eslint --cache --ext .ts,.js,.mts,.mjs src/",
+    "lint:dpdm": "dpdm --exit-code circular:1 --no-warning --no-tree src/*.ts src/**/*.ts src/*.js src/**/*.js src/*.mts src/**/*.mts src/*.mjs src/**/*.mjs",
+    "lint": "yarn lint:eslint && yarn lint:dpdm",
+    "lint:fix": "yarn lint:eslint --fix && yarn lint:dpdm",
     "prepack": "yarn run build",
     "typecheck": "tsc --noEmit",
     "test": "vitest run",
@@ -93,6 +97,13 @@
     "@types/react-dom": "^19.0.3",
     "@types/semver": "^7.7.0",
     "@types/uuid": "^10.0.0",
+    "dpdm": "^3.12.0",
+    "eslint": "^8.33.0",
+    "eslint-config-airbnb-base": "^15.0.0",
+    "eslint-config-prettier": "^8.6.0",
+    "eslint-plugin-import": "^2.29.1",
+    "eslint-plugin-no-instanceof": "^1.0.1",
+    "eslint-plugin-prettier": "^4.2.1",
     "jose": "^6.0.10",
     "postgres": "^3.4.5",
     "prettier": "^2.8.3",

libs/langgraph-api/src/api/assistants.mts

@@ -4,16 +4,17 @@ import { Hono } from "hono";
 import { v4 as uuid } from "uuid";
 import { z } from "zod";
 
+import { HTTPException } from "hono/http-exception";
 import {
   getAssistantId,
   getCachedStaticGraphSchema,
   getGraph,
 } from "../graph/load.mjs";
 import { getRuntimeGraphSchema } from "../graph/parser/index.mjs";
 
-import { HTTPException } from "hono/http-exception";
 import * as schemas from "../schemas.mjs";
 import { Assistants } from "../storage/ops.mjs";
+
 const api = new Hono();
 
 const RunnableConfigSchema = z.object({

libs/langgraph-api/src/api/meta.mts

@@ -31,19 +31,19 @@ try {
 }
 
 // read env variable
-const env = process.env;
+const {env} = process;
 
 api.get("/info", (c) => {
-  const langsmithApiKey = env["LANGSMITH_API_KEY"] || env["LANGCHAIN_API_KEY"];
+  const langsmithApiKey = env.LANGSMITH_API_KEY || env.LANGCHAIN_API_KEY;
 
   const langsmithTracing = (() => {
     if (langsmithApiKey) {
       // Check if any tracing variable is explicitly set to "false"
       const tracingVars = [
-        env["LANGCHAIN_TRACING_V2"],
-        env["LANGCHAIN_TRACING"],
-        env["LANGSMITH_TRACING_V2"],
-        env["LANGSMITH_TRACING"],
+        env.LANGCHAIN_TRACING_V2,
+        env.LANGCHAIN_TRACING,
+        env.LANGSMITH_TRACING_V2,
+        env.LANGSMITH_TRACING,
       ];
 
       // Return true unless explicitly disabled

libs/langgraph-api/src/api/runs.mts

@@ -81,9 +81,9 @@ const createValidRun = async (
   if (auth) {
     userId = auth.user.identity ?? auth.user.id;
     config.configurable ??= {};
-    config.configurable["langgraph_auth_user"] = auth.user;
-    config.configurable["langgraph_auth_user_id"] = userId;
-    config.configurable["langgraph_auth_permissions"] = auth.scopes;
+    config.configurable.langgraph_auth_user = auth.user;
+    config.configurable.langgraph_auth_user_id = userId;
+    config.configurable.langgraph_auth_permissions = auth.scopes;
   }
 
   let feedbackKeys =

libs/langgraph-api/src/api/store.mts

@@ -1,9 +1,9 @@
 import { Hono } from "hono";
 import { zValidator } from "@hono/zod-validator";
-import * as schemas from "../schemas.mjs";
 import { HTTPException } from "hono/http-exception";
-import { store as storageStore } from "../storage/store.mjs";
 import type { Item } from "@langchain/langgraph";
+import * as schemas from "../schemas.mjs";
+import { store as storageStore } from "../storage/store.mjs";
 import { handleAuthEvent } from "../auth/custom.mjs";
 
 const api = new Hono();
@@ -17,8 +17,8 @@ const validateNamespace = (namespace: string[]) => {
     if (!label || label.includes(".")) {
       throw new HTTPException(422, {
         message:
-          "Namespace labels cannot be empty or contain periods. Received: " +
-          namespace.join("."),
+          `Namespace labels cannot be empty or contain periods. Received: ${ 
+          namespace.join(".")}`,
       });
     }
   }
@@ -136,8 +136,8 @@ api.get(
       key: payload.key,
     });
 
-    const key = payload.key;
-    const namespace = payload.namespace;
+    const {key} = payload;
+    const {namespace} = payload;
     return c.json(mapItemsToApi(await storageStore.get(namespace, key)));
   }
 );

libs/langgraph-api/src/cli/entrypoint.mts

@@ -1,8 +1,8 @@
 import { asyncExitHook } from "exit-hook";
 import * as process from "node:process";
+import { Client as LangSmithClient } from "langsmith";
 import { startServer, StartServerSchema } from "../server.mjs";
 import { connectToServer } from "./utils/ipc/client.mjs";
-import { Client as LangSmithClient } from "langsmith";
 import { logger } from "../logging.mjs";
 
 logger.info(`Starting server...`);

libs/langgraph-api/src/command.mts

@@ -12,7 +12,7 @@ export interface RunCommand {
 }
 
 export const getLangGraphCommand = (command: RunCommand) => {
-  let goto =
+  const goto =
     command.goto != null && !Array.isArray(command.goto)
       ? [command.goto]
       : command.goto;

libs/langgraph-api/src/experimental/embed.mts

@@ -9,10 +9,10 @@ import { streamSSE } from "hono/streaming";
 import { RunnableConfig } from "@langchain/core/runnables";
 import { v4 as uuidv4 } from "uuid";
 
+import { z } from "zod";
 import type { Metadata, Run } from "../storage/ops.mjs";
 import * as schemas from "../schemas.mjs";
 
-import { z } from "zod";
 import { streamState } from "../stream.mjs";
 import { serialiseAsDict, serializeError } from "../utils/serde.mjs";
 import { getDisconnectAbortSignal, jsonExtra } from "../utils/hono.mjs";
@@ -62,11 +62,10 @@ function createStubRun(
     : undefined;
 
   if (streamMode == null || streamMode.length === 0) streamMode = ["values"];
-  const config = Object.assign(
-    {},
-    payload.config ?? {},
-    {
-      configurable: {
+  const config = {
+
+    ...payload.config ?? {},
+    configurable: {
         run_id: runId,
         thread_id: threadId,
         graph_id: payload.assistant_id,
@@ -81,9 +80,8 @@ function createStubRun(
             }
           : null),
       },
-    },
-    { metadata: payload.metadata ?? {} }
-  );
+    metadata: payload.metadata ?? {}
+  };
 
   return {
     run_id: runId,

libs/langgraph-api/src/graph/load.mts

@@ -1,14 +1,14 @@
 import { z } from "zod";
 
 import * as uuid from "uuid";
-import { Assistants } from "../storage/ops.mjs";
 import type {
   BaseCheckpointSaver,
   BaseStore,
   CompiledGraph,
   LangGraphRunnableConfig,
 } from "@langchain/langgraph";
 import { HTTPException } from "hono/http-exception";
+import { Assistants } from "../storage/ops.mjs";
 import { type CompiledGraphFactory, resolveGraph } from "./load.utils.mjs";
 import type { GraphSchema, GraphSpec } from "./parser/index.mjs";
 import { getStaticGraphSchema } from "./parser/index.mjs";

libs/langgraph-api/src/graph/parser/parser.mts

@@ -2,9 +2,9 @@ import * as ts from "typescript";
 import * as vfs from "@typescript/vfs";
 import * as path from "node:path";
 import dedent from "dedent";
-import { buildGenerator } from "./schema/types.mjs";
 import { fileURLToPath } from "node:url";
 import type { JSONSchema7 } from "json-schema";
+import { buildGenerator } from "./schema/types.mjs";
 
 interface GraphSchema {
   state: JSONSchema7 | undefined;
@@ -29,11 +29,15 @@ const INFER_TEMPLATE_PATH = path.resolve(
 
 export class SubgraphExtractor {
   protected program: ts.Program;
+
   protected checker: ts.TypeChecker;
+
   protected sourceFile: ts.SourceFile;
+
   protected inferFile: ts.SourceFile;
 
   protected anyPregelType: ts.Type;
+
   protected anyGraphType: ts.Type;
 
   protected strict: boolean;
@@ -56,11 +60,11 @@ export class SubgraphExtractor {
   }
 
   private findTypeByName = (needle: string) => {
-    let result: ts.Type | undefined = undefined;
+    let result: ts.Type | undefined;
 
     const visit = (node: ts.Node) => {
       if (ts.isTypeAliasDeclaration(node)) {
-        const symbol = (node as any).symbol;
+        const {symbol} = (node as any);
 
         if (symbol != null) {
           const name = this.checker
@@ -81,7 +85,7 @@ export class SubgraphExtractor {
     root: ts.Node,
     predicate: (node: ts.Node) => boolean
   ): ts.Node | undefined => {
-    let result: ts.Node | undefined = undefined;
+    let result: ts.Node | undefined;
 
     const visit = (node: ts.Node) => {
       if (predicate(node)) {
@@ -158,7 +162,7 @@ export class SubgraphExtractor {
             }
 
             acc.push({
-              namespace: namespace,
+              namespace,
               node: nodeName,
               subgraph: variables[0],
             });
@@ -585,10 +589,10 @@ export class SubgraphExtractor {
     const allDiagnostics = ts.getPreEmitDiagnostics(extract);
     for (const diagnostic of allDiagnostics) {
       let message =
-        ts.flattenDiagnosticMessageText(diagnostic.messageText, "\n") + "\n";
+        `${ts.flattenDiagnosticMessageText(diagnostic.messageText, "\n")  }\n`;
 
       if (diagnostic.file) {
-        const fileName = diagnostic.file.fileName;
+        const {fileName} = diagnostic.file;
         const { line, character } = ts.getLineAndCharacterOfPosition(
           diagnostic.file,
           diagnostic.start!
@@ -602,7 +606,7 @@ export class SubgraphExtractor {
 
     const schemaGenerator = buildGenerator(extract);
     const trySymbol = (symbol: string) => {
-      let schema: JSONSchema7 | undefined = undefined;
+      let schema: JSONSchema7 | undefined;
       try {
         schema = schemaGenerator?.getSchemaForSymbol(symbol) ?? undefined;
       } catch (e) {
@@ -614,7 +618,7 @@ export class SubgraphExtractor {
 
       if (schema == null) return undefined;
 
-      const definitions = schema.definitions;
+      const {definitions} = schema;
       if (definitions == null) return schema;
 
       const toReplace = Object.keys(definitions).flatMap((key) => {