Adds console disclaimer when running direct sql from the browser (#158)

Config example for websocket:

```javascript
                neonConfig.disableWarningBrowser = false;
                const pool = new Pool({ connectionString });
```

```javascript
                const sql = neon(connectionString, {
                  disableWarningBrowser: true
                });
```

<img width="1085" alt="image"
src="https://github.com/user-attachments/assets/af77e1a5-340e-4e80-8530-0a33b1292f5d"
/>


I guess for now this should be enough, we can document it later if
needed. This way is a good way to get some signal if there are a lot of
people disabling it

Author: lneves12

.gitignore

@@ -6,3 +6,4 @@
 
 node_modules
 build
+/.idea

src/client.ts

@@ -1,5 +1,6 @@
 import { Client, Connection, type ClientConfig } from 'pg';
 import { Socket } from './shims/net';
+import { warnIfBrowser } from './utils';
 
 export declare interface NeonClient {
   connection: Connection & {
@@ -95,6 +96,10 @@ export class NeonClient extends Client {
 
       const connectEvent = this.ssl ? 'sslconnect' : 'connect';
       con.on(connectEvent, () => {
+        if (!this.neonConfig.disableWarningInBrowsers) {
+          warnIfBrowser();
+        }
+
         this._handleAuthCleartextPassword();
         this._handleReadyForQuery();
       });

src/httpQuery.ts

@@ -27,6 +27,9 @@ import type {
   ParameterizedQuery,
 } from './httpTypes';
 import { SqlTemplate, UnsafeRawSql } from './sqlTemplate';
+import { warnIfBrowser } from './utils';
+
+import { Socket as neonConfig } from './shims/net';
 
 // @ts-ignore -- this isn't officially exported by pg
 import TypeOverrides from 'pg/lib/type-overrides';
@@ -192,6 +195,7 @@ export function neon<
     readOnly: neonOptReadOnly,
     deferrable: neonOptDeferrable,
     authToken,
+    disableWarningInBrowsers,
   }: HTTPTransactionOptions<ArrayMode, FullResults> = {},
 ): NeonQueryFunction<ArrayMode, FullResults> {
   // check the connection string
@@ -365,6 +369,10 @@ export function neon<
         headers['Neon-Batch-Deferrable'] = String(resolvedDeferrable);
     }
 
+    if (!(disableWarningInBrowsers || neonConfig.disableWarningInBrowsers)) {
+      warnIfBrowser();
+    }
+
     // --- run query ---
 
     let response;

src/httpTypes.ts

@@ -64,6 +64,14 @@ export interface HTTPQueryOptions<
    * Custom type parsers. See https://github.com/brianc/node-pg-types.
    */
   types?: typeof PgTypes;
+
+  /**
+   * When `disableWarningInBrowsers` is set to `true`, it disables the warning about
+   * running this driver in the browser.
+   *
+   * Default: `false`
+   */
+  disableWarningInBrowsers?: boolean;
 }
 
 export interface HTTPTransactionOptions<

src/index.ts

@@ -19,9 +19,20 @@ circumstances are right.
 import type { ClientBase as PgClientBase } from 'pg';
 import { type SocketDefaults } from './shims/net';
 
+// Ensure we are very explicit while using these apis. This ensures more type safety
+// specially since this library is made to run both in the browser and node.js environments.
+declare global {
+  const window: Window | undefined;
+  const document: Document | undefined;
+
+  interface Window {}
+  interface Document {}
+}
+
 export * from './httpQuery';
 export * from './sqlTemplate';
 export type * from './httpTypes';
+export * from './utils';
 
 export { NeonPool as Pool, type NeonPoolClient as PoolClient } from './pool';
 export { NeonClient as Client } from './client';

src/shims/net/index.ts

@@ -102,6 +102,7 @@ export interface SocketDefaults {
   rootCerts: string;
   pipelineTLS: boolean;
   disableSNI: boolean;
+  disableWarningInBrowsers: boolean;
 }
 type GlobalOnlyDefaults =
   | 'poolQueryViaFetch'
@@ -142,6 +143,7 @@ export class Socket extends EventEmitter {
     rootCerts: '',
     pipelineTLS: false,
     disableSNI: false,
+    disableWarningInBrowsers: false,
   };
 
   static opts: Partial<SocketDefaults> = {};
@@ -345,6 +347,34 @@ export class Socket extends EventEmitter {
     this.opts.disableSNI = newValue;
   }
 
+  /**
+   * When `disableWarningInBrowsers` is set to `true`, it disables the warning about
+   * running this driver in the browser.
+   *
+   * Default: `false`.
+   */
+  static get disableWarningInBrowsers() {
+    return (
+      Socket.opts.disableWarningInBrowsers ??
+      Socket.defaults.disableWarningInBrowsers
+    );
+  }
+  static set disableWarningInBrowsers(
+    newValue: SocketDefaults['disableWarningInBrowsers'],
+  ) {
+    Socket.opts.disableWarningInBrowsers = newValue;
+  }
+  get disableWarningInBrowsers() {
+    return (
+      this.opts.disableWarningInBrowsers ?? Socket.disableWarningInBrowsers
+    );
+  }
+  set disableWarningInBrowsers(
+    newValue: SocketDefaults['disableWarningInBrowsers'],
+  ) {
+    this.opts.disableWarningInBrowsers = newValue;
+  }
+
   /**
    * Pipelines the startup message, cleartext password message and first query
    * when set to `"password"`. This works only for cleartext password auth.

src/utils.ts

@@ -0,0 +1,30 @@
+/**
+ * Detects if the code is running in a browser environment and displays a warning
+ * about the security implications of running SQL directly from the browser.
+ */
+export function warnIfBrowser(): void {
+  const isBrowser =
+    typeof window !== 'undefined' && typeof document !== 'undefined';
+  if (
+    isBrowser &&
+    typeof console !== 'undefined' &&
+    typeof console.warn === 'function'
+  ) {
+    console.warn(`          
+        ************************************************************
+        *                                                          *
+        *  WARNING: Running SQL directly from the browser can have *
+        *  security implications. Even if your database is         *
+        *  protected by Row-Level Security (RLS), use it at your   *
+        *  own risk. This approach is great for fast prototyping,  *
+        *  but ensure proper safeguards are in place to prevent    *
+        *  misuse or execution of expensive SQL queries by your    *
+        *  end users.                                              *
+        *                                                          *
+        *  If you've assessed the risks, suppress this message     *
+        *  using the disableWarningInBrowsers configuration        *
+        *  parameter.                                              *
+        *                                                          *
+        ************************************************************`);
+  }
+}