create a decorator for Nest.js middleware which will be check NODE\_ENV variable and if it equal true - call next() but if NODE\_ENV equal false - return false
create a decorator for Nest.js middleware which will be check NODE\_ENV variable and if it equal true - call next() but if NODE\_ENV equal false - return false
user
To create the desired decorator, we'll first need to create a Nest.js middleware function. This middleware function will check the `NODE_ENV` variable and determine whether to call the next middleware or return an HTTP response with the status 403 (Forbidden).

Here's the code for the middleware function:

```typescript
import { Injectable, NestMiddleware } from "@nestjs/common";
import { Request, Response, NextFunction } from "express";

@Injectable()
export class EnvironmentCheckMiddleware implements NestMiddleware {
  use(req: Request, res: Response, next: NextFunction) {
    if (process.env.NODE_ENV === "true") {
      next();
    } else {
      res.status(403).send(false);
    }
  }
}
```

Next, we'll create a decorator, which will be a higher-order function that wraps the Nest.js middleware. This decorator can be used to apply the middleware on the desired routes.

```typescript
import { applyDecorators, UseGuards } from "@nestjs/common";
import { EnvironmentCheckMiddleware } from "./environment-check.middleware";
import { APP_GUARD } from "@nestjs/core";

export function CheckEnvironment() {
  return applyDecorators(
    UseGuards({
      useClass: EnvironmentCheckMiddleware,
      provide: APP_GUARD,
    })
  );
}
```

Now, you can use the `@CheckEnvironment()` decorator in your controllers to specify which routes should apply this middleware.

```typescript
import { Controller, Get } from "@nestjs/common";
import { CheckEnvironment } from "./check-environment.decorator";

@Controller()
export class AppController {
  constructor() {}

  @CheckEnvironment()
  @Get("secret")
  getSecret() {
    return "This is the secret endpoint";
  }
}
```

In the example above, the `getSecret()` route will employ the middleware to check the `NODE_ENV` variable, which will either validate the request or return a 403 Forbidden error.
assistant
To create a Nest.js decorator that checks the `NODE_ENV` variable and calls the next middleware function if it's set to `true`, and returns `false` otherwise, you can follow these steps:

1. Create a new file (e.g., `envGuard.decorator.ts`) in your Nest.js project.
2. Import the necessary dependencies:

   ```typescript
   import { Injectable, CanActivate, ExecutionContext } from '@nestjs/common';
   import { Observable } from 'rxjs';
   ```

3. Define the `EnvGuard` decorator class:

   ```typescript
   @Injectable()
   export class EnvGuard implements CanActivate {
     canActivate(context: ExecutionContext): boolean | Observable<boolean> {
       const req = context.switchToHttp().getRequest();
       const env = req.env;

       if (env === 'production' || env === 'staging') {
         return true; // Call next middleware function
       } else {
         return false; // Return false
       }
     }
   }
   ```

   In this implementation, we're checking if the `NODE_ENV` variable is set to `production` or `staging`, which are commonly used for production and staging environments. If it's either of these, we're allowing the middleware to proceed by returning `true`. Otherwise, we're returning `false`.

4. Decorate your middleware function with the `EnvGuard` decorator:

   ```typescript
   import { UseGuards } from '@nestjs/common';
   import { EnvGuard } from './env-guard.decorator';

   @UseGuards(EnvGuard)
   export class MyMiddleware {
     // ...
   }
   ```

   This will ensure that the middleware function is only executed if the `NODE_ENV` variable is set to `production` or `staging`.

Note that this implementation assumes that the `NODE_ENV` variable is set in the environment configuration file (e.g., `.env` or `.env.local`). If you're using a different approach to set the `NODE_ENV`, you'll need to modify the code accordingly.
create a decorator for Nest.js middleware which will be check NODE\_ENV variable and if it equal true - call next() but if NODE\_ENV equal false - return false
user
To create the desired decorator, we'll first need to create a Nest.js middleware function. This middleware function will check the `NODE_ENV` variable and determine whether to call the next middleware or return an HTTP response with the status 403 (Forbidden).

Here's the code for the middleware function:

```typescript
import { Injectable, NestMiddleware } from "@nestjs/common";
import { Request, Response, NextFunction } from "express";

@Injectable()
export class EnvironmentCheckMiddleware implements NestMiddleware {
  use(req: Request, res: Response, next: NextFunction) {
    if (process.env.NODE_ENV === "true") {
      next();
    } else {
      res.status(403).send(false);
    }
  }
}
```

Next, we'll create a decorator, which will be a higher-order function that wraps the Nest.js middleware. This decorator can be used to apply the middleware on the desired routes.

```typescript
import { applyDecorators, UseGuards } from "@nestjs/common";
import { EnvironmentCheckMiddleware } from "./environment-check.middleware";
import { APP_GUARD } from "@nestjs/core";

export function CheckEnvironment() {
  return applyDecorators(
    UseGuards({
      useClass: EnvironmentCheckMiddleware,
      provide: APP_GUARD,
    })
  );
}
```

Now, you can use the `@CheckEnvironment()` decorator in your controllers to specify which routes should apply this middleware.

```typescript
import { Controller, Get } from "@nestjs/common";
import { CheckEnvironment } from "./check-environment.decorator";

@Controller()
export class AppController {
  constructor() {}

  @CheckEnvironment()
  @Get("secret")
  getSecret() {
    return "This is the secret endpoint";
  }
}
```

In the example above, the `getSecret()` route will employ the middleware to check the `NODE_ENV` variable, which will either validate the request or return a 403 Forbidden error.
assistant
create a decorator for Nest.js middleware which will be check NODE\_ENV variable and if it equal true - call next() but if NODE\_ENV equal false - return false
user
const Decorator = function (next) {
    if (process.env.NODE_ENV === 'true') {
        next();
    }
    return false;
};

export default Decorator;
assistant