fiber/docs/api/middleware/timeout.md

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---
id: timeout
---
# Timeout
There exist two distinct implementations of timeout middleware [Fiber](https://github.com/gofiber/fiber).
**New**
As a `fiber.Handler` wrapper, it creates a context with `context.WithTimeout` and pass it in `UserContext`.
If the context passed executions (eg. DB ops, Http calls) takes longer than the given duration to return, the timeout error is set and forwarded to the centralized `ErrorHandler`.
It does not cancel long running executions. Underlying executions must handle timeout by using `context.Context` parameter.
## Signatures
```go
func New(handler fiber.Handler, timeout time.Duration, timeoutErrors ...error) fiber.Handler
```
## Examples
Import the middleware package that is part of the Fiber web framework
```go
import (
"github.com/gofiber/fiber/v3"
"github.com/gofiber/fiber/v3/middleware/timeout"
)
```
After you initiate your Fiber app, you can use the following possibilities:
```go
func main() {
app := fiber.New()
h := func(c fiber.Ctx) error {
sleepTime, _ := time.ParseDuration(c.Params("sleepTime") + "ms")
if err := sleepWithContext(c.UserContext(), sleepTime); err != nil {
return fmt.Errorf("%w: execution error", err)
}
return nil
}
app.Get("/foo/:sleepTime", timeout.New(h, 2*time.Second))
log.Fatal(app.Listen(":3000"))
}
func sleepWithContext(ctx context.Context, d time.Duration) error {
timer := time.NewTimer(d)
select {
case <-ctx.Done():
if !timer.Stop() {
<-timer.C
}
return context.DeadlineExceeded
case <-timer.C:
}
return nil
}
```
Test http 200 with curl:
```bash
curl --location -I --request GET 'http://localhost:3000/foo/1000'
```
Test http 408 with curl:
```bash
curl --location -I --request GET 'http://localhost:3000/foo/3000'
```
Use with custom error:
```go
var ErrFooTimeOut = errors.New("foo context canceled")
func main() {
app := fiber.New()
h := func(c fiber.Ctx) error {
sleepTime, _ := time.ParseDuration(c.Params("sleepTime") + "ms")
if err := sleepWithContextWithCustomError(c.UserContext(), sleepTime); err != nil {
return fmt.Errorf("%w: execution error", err)
}
return nil
}
app.Get("/foo/:sleepTime", timeout.New(h, 2*time.Second, ErrFooTimeOut))
log.Fatal(app.Listen(":3000"))
}
func sleepWithContextWithCustomError(ctx context.Context, d time.Duration) error {
timer := time.NewTimer(d)
select {
case <-ctx.Done():
if !timer.Stop() {
<-timer.C
}
return ErrFooTimeOut
case <-timer.C:
}
return nil
}
```
Sample usage with a DB call:
```go
func main() {
app := fiber.New()
db, _ := gorm.Open(postgres.Open("postgres://localhost/foodb"), &gorm.Config{})
handler := func(ctx fiber.Ctx) error {
tran := db.WithContext(ctx.UserContext()).Begin()
if tran = tran.Exec("SELECT pg_sleep(50)"); tran.Error != nil {
return tran.Error
}
if tran = tran.Commit(); tran.Error != nil {
return tran.Error
}
return nil
}
app.Get("/foo", timeout.New(handler, 10*time.Second))
log.Fatal(app.Listen(":3000"))
}
```