# Guard

<figure><img src="/files/NyuEPKPRensFLGXXRDzJ" alt=""><figcaption></figcaption></figure>

Guard is a middleware only use for manage access in route. It is a function return bool value if true the route can be handler, else app will throw 403 error. Have two guard for each level. `Guard` for Controller and `AppGuard` for Module.

```go
type Guard func(ctrl *DynamicController, ctx *Ctx) bool

type AppGuard func(module *DynamicModule, ctx Ctx) bool
```

### Define guard and use in controller

```go
package app

import "github.com/tinh-tinh/tinhtinh/core"

func QueryGuard(ctrl *DynamicController, ctx *Ctx) bool {
    return ctx.Query("key") == "value"
}

func Controller(module *core.DynamicModule) *core.DynamicController {
    ctrl := module.NewController("test")
    
    ctrl.Guard(QueryGuard).Get("", func (ctx core.Ctx) error {
        return ctx.JSON(core.Map{
            "data": "ok",
        })
    })
    
    return ctrl
}
```

### Define guard and use in module

```go
package app

import "github.com/tinh-tinh/tinhtinh/core"

func QueryGuard(module *core.DynamicModule, ctx *Ctx) bool {
    return ctx.Query("key") == "value"
}

func Controller(module *core.DynamicModule) *core.DynamicModule {
    mod := module.New(core.NewModuleOptions{
        Guards: []core.AppGuard{QueryGuard},
    })
    
    return mod
}
```


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