README
¶
Error Wrapper
Error Wrapper creates an wrapper for the error type in Go which captures the File, Line and Stack of where it was called.
Installation
go get -u github.com/txgruppi/werr
Why?
I don't like to use panic.
I want my apps to run forever and just output errors to a log.
Usually I write my logs using logger.Printf("%#v", err) but I needed more info related to the error, so I created this package.
Example
package main
import (
"fmt"
"os"
"github.com/txgruppi/werr"
)
func main() {
file, err := os.Open("/tmp/my-missing-file")
if err != nil {
err = werr.Wrap(err) // Wrap it
fmt.Println(err.Error()) // Return the original error message
if wrapped, ok := err.(*werr.Wrapper); ok { // Try to convert to `*werr.Wrapper`
lg, _ := wrapped.Log() // Generate the log message
fmt.Println(lg) // Print the log message
}
}
defer file.Close()
}
This code will output something line this:
open /tmp/my-missing-file: no such file or directory
/Users/txgruppi/code/temp/test.go:13 open /tmp/my-missing-file: no such file or directory
goroutine 1 [running]:
github.com/txgruppi/werr.Wrap(0x2208246900, 0x208270300, 0x0, 0x0)
/Users/txgruppi/code/go/src/github.com/txgruppi/werr/funcs.go:24 +0x153
main.main()
/Users/txgruppi/code/temp/test.go:13 +0x72
Tests
go get -u -t github.com/txgruppi/werr
cd $GOPATH/src/github.com/txgruppi/werr
go test ./...
License
MIT
Documentation
¶
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ( // StackArraySize defines the number of bytes which will be allocated for the // stack trace. // Any value `<= 0` will result in not creating the stack trace. StackArraySize = 512 // LogLine is the format used by `*Wrapper.Log()`. // It should be a valid `text/template` string. // The data passed to the `Execute` method of the template is the `*Wrapper` // instance, which means that you can use all `*Wrapper` methods and // attributes inside the template. LogLine = "{{.File}}:{{.Line}} {{.Original.Error}}\n{{printf \"%s\" .Stack}}\n\n" )
Functions ¶
func Unwrap ¶
Unwrap returns the original error inside an `*Wrapper` instance. If `err` is `nil` it will return `nil`. If `err` is an instance of `*Wrapper` it will return the value of the `Original` attribute. Anything else will be returned without any modification.
func Wrap ¶
Wrap creates an `*Wrapper` instance with the file, line and stack trace of the moment when it is called. If `StackArraySize` is `<= 0` the stack trace will not be generated. If `err` is `nil` it will return `nil`. If `err` is an `*Wrapper` it will return the same `err` variable. Anything else will be put in the `Original` attribute of `*Wrapper`
Source Files