README
¶
goroutine
A goroutine wrapper for creating and running panic safe goroutines.
The purpose of this package is to provide a simple wrapper function for goroutines, which automatically handles panics in goroutines. Starting a new goroutine without taking care of recovering from a possible panic in that goroutine itself could crash the whole application.
The Go function runs an arbitrary function f in a separate goroutine, which handles the recovering from panic within
that goroutine.
Installation
go get -u github.com/sknr/Goroutine
Usage (with dot import)
Instead of running
go func() {
panic("Panic raised in Goroutine")
}()
simply call
Go(func() {
panic("Panic raised in Goroutine")
})
in order to create a panic safe goroutine.
Functions with multiple input params must be wrapped within an anonymous function.
Instead of running
go func(a, b int) {
panic(a+b)
}(21,21)
simply call
Go(func() {
func(a, b int) {
panic(a+b)
}(21,21)
})
Examples
package main
import (
"fmt"
"github.com/sknr/goroutine"
"log"
)
func init() {
// Override the default recover function.
goroutine.SetDefaultRecoverFunc(func(v interface{}, done chan<- error) {
log.Printf("%v", v)
done <- fmt.Errorf("panic in goroutine successfully recovered")
})
}
func main() {
for i := -3; i <= 3; i++ {
err := <-goroutine.Go(func() {
func(a, b int) {
log.Println(a, "/", b, "=", a/b)
}(10, i)
})
if err != nil {
log.Println(err)
}
}
}
Set a new default recover function
In order to override the default recover function for new goroutines (created with Go(func()) or New(func())),
simply set a custom recover function of type RecoverFunc with SetDefaultRecoverFunc
Create a new Goroutine instance with a custom recover function
If you need different recover functions for different goroutines, you can simply call
goroutine.New(func() {
func(name string) {
panic(fmt.Sprintln("Hallo", name))
}("Welt")
}).WithRecoverFunc(func(v interface{}, done chan<- error) {
log.Printf("Custom recover function in Goroutine, with error: %v", v)
}).Go()
Documentation
¶
Overview ¶
Package Goroutine provides a small wrapper around go's goroutines, in order to easily create panic safe goroutines. Starting a new goroutine without taking care of recovering from a possible panic in that goroutine itself could crash the whole application. Therefore, in case of a panic, triggered by the goroutine which was created by the Go method, the panic will be automatically recovered and the error will be notified via the done channel.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrPanicRecovered is returned when a goroutine has panicked. ErrPanicRecovered = &panicError{message: "panic in goroutine recovered", value: nil} // ErrRecoverFuncPanicRecovered is returned when the recover function of a goroutine has panicked. ErrRecoverFuncPanicRecovered = &panicError{message: "panic in recover function of goroutine recovered", value: nil} )
Functions ¶
func Go ¶
func Go(f func()) <-chan error
Go runs a function f in a separate goroutine, which does automatically handle the recovering from a panic within that goroutine.
Example ¶
package main
import (
"fmt"
"github.com/sknr/goroutine"
)
func main() {
// Instead of
go func() {
values := [3]int{1, 2, 3}
for i := 0; i < 4; i++ {
fmt.Println(values[i])
}
}()
// simply call
goroutine.Go(func() {
values := [3]int{1, 2, 3}
for i := 0; i < 4; i++ {
fmt.Println(values[i])
}
})
}
Example (WithInputParam) ¶
package main
import (
"github.com/sknr/goroutine"
)
func main() {
// Functions with input params need to be wrapped by an anonymous function.
// Instead of
go func(s string) {
panic(s)
}("Hello World")
// simply call
goroutine.Go(func() {
func(s string) {
panic(s)
}("Hello World")
})
}
func SetDefaultRecoverFunc ¶
func SetDefaultRecoverFunc(rf RecoverFunc)
SetDefaultRecoverFunc can be used to override the defaultRecoverFunc which is used by Go method.
Note: If you pass nil as a RecoverFunc, the panic will be silently recovered.
Types ¶
type Goroutine ¶
type Goroutine struct {
// contains filtered or unexported fields
}
Goroutine type contains the function f to run within that goroutine and the recover function rf. The recover function rf will be called in case of a panic in f within that goroutine.
func New ¶ added in v0.4.1
func New(f func()) *Goroutine
New creates a new panic safe Goroutine, with the defaultRecoverFunc as recover function.
Example ¶
package main
import (
"fmt"
"github.com/sknr/goroutine"
)
func main() {
err := <-goroutine.New(func() {
values := [3]int{1, 2, 3}
for i := 0; i < 4; i++ {
fmt.Println(values[i])
}
}).Go()
fmt.Println(err)
}
Output: 1 2 3 panic in goroutine recovered: runtime error: index out of range [3] with length 3
func (*Goroutine) Go ¶ added in v0.4.1
The Go method starts a new goroutine which is panic safe. A possible panic will be recovered by the recover function, either set by SetDefaultRecoverFunc or WithRecover.
func (*Goroutine) WithRecover ¶ added in v0.4.1
func (g *Goroutine) WithRecover(rf RecoverFunc) *Goroutine
WithRecover overrides the default recover function with rf.
Note: If you pass nil as a RecoverFunc, the panic will be silently recovered.
Example ¶
package main
import (
"fmt"
"github.com/sknr/goroutine"
)
func main() {
err := <-goroutine.New(func() {
values := [3]int{1, 2, 3}
for i := 0; i < 4; i++ {
fmt.Println(values[i])
}
}).WithRecover(func(v interface{}, done chan<- error) {
if err, ok := v.(error); ok {
done <- err
return
}
done <- fmt.Errorf("recovered: %v", v)
}).Go()
fmt.Println(err)
}
Output: 1 2 3 runtime error: index out of range [3] with length 3
type RecoverFunc ¶
type RecoverFunc func(v interface{}, done chan<- error)
The RecoverFunc type defines the signature of a recover function within a Goroutine.
func GetDefaultRecoverFunc ¶
func GetDefaultRecoverFunc() RecoverFunc
GetDefaultRecoverFunc returns the current default recover function for goroutines used by the Go method.
Source Files