# Middleware

#### Example of middleware

```typescript
// Middle({cancel: Record<string, any>, handler: (req: ArcRequest) => Promise<boolean>})

const middle: Middle = {
    cancel: { // JSON returned after false handler
        message: "Too young"
    },
    handler: async(req: ArcRequest): Promise<boolean> => // Callback to check anything
    {
        let age = 16;
        return age >= 18;
    }
};
```

#### Adding middleware to route

```typescript
const middle: Middle = {
    cancel: { // JSON returned after false handler
        message: "Too young"
    },
    handler: async(req: ArcRequest): Promise<boolean> => // Callback to check anything
    {
        let age = 16;
        return age >= 18;
    }
};
const GET = async(req: ArcRequest, res: ArcResponse) =>
{
    res.setMiddle(middle);
    return {
        message = "Old enough"
    };
};
```