UhOh
Golang advanced error usage with stack tracing
uhoh consists of a few parts:
- Original error
- Description of error
- Type error
- Stack trace
- File
- Function
- Line
- Date
Simple Usage
Uhoh can be as descriptive or as simple as you want. The only thing it requires is an initial error.
import "github.com/brianvoe/uhoh"
// Create new uhoh error
err := uhoh.New(errors.New("original error"))
fmt.Println(err.Error())
// Output:
// 2021-09-12T01:20:30Z | original error
Advanced Usage
Lets see what uhoh can do with a more data and output values.
// Create error
err := New(errors.New("original error"))
err.SetDescribe(errors.New("describe error"))
err.SetType(uhoh.ErrGeneral)
// Output info
fmt.Println(err.Error())
fmt.Println(err.Stack)
// Output:
// 2021-09-12T01:20:30Z | general error | original error | describe error
// [{uhoh_test.go Example 16} {run_example.go runExample 64} {example.go runExamples 44}]
Using With Str
In order to simplify the use of uhoh, uhoh has Str equivalents for set methods so you dont have to always initiate an errors.New().
// Create error
err := uhoh.NewStr("original error")
err.SetDescribeStr("describe error")
err.SetTypeStr("general error")
// Output info
fmt.Println(err.Error())
fmt.Println(err.Stack)
// Output:
// 2021-09-12T01:20:30Z | general error | original error | describe error
// [{uhoh_test.go Example 16} {run_example.go runExample 64} {example.go runExamples 44}]
Real World Usage
To give you a better understanding of how uhoh works, let's look at a real world example
var fileErrType = errors.New("file error")
_, err := os.Open("/test.txt")
if err != nil {
uhohErr := uhoh.New(err)
uhohErr.SetDescribe(errors.New("Failed to open file. Please check settings."))
uhohErr.SetType(fileErrType)
// Lets log out all the uhoh fields
log.Printf("%s", uhohErr.ToJson())
}
{
"original": "open /test.txt: no such file or directory",
"describe": "Failed to open file. Please check settings.",
"type": "file error",
"stack": [
{ "file": "uhoh_test.go", "function": "Example_realWorld", "line": 40 },
{ "file": "run_example.go", "function": "runExample", "line": 64 },
{ "file": "example.go", "function": "runExamples", "line": 44 }
],
"date": "2021-09-12T01:20:30Z"
}
Type for Is checking
You may want to check if an error is of a certain type. Uhoh has a list of types that you can use to check if an error is of a certain type. Otherwise you can set your own internal types.
var (
ErrValidation = errors.New("validation error")
ErrFile = errors.New("file error")
ErrNetwork = errors.New("network error")
)
func main() {
err := Validate()
if err != nil {
if uhoh.Is(err, ErrValidation) {
// do something
}
}
}
func Validate() error {
return uhoh.New(errors.New("field is invalid")).SetType(ErrValidation)
}
// Output json of everything
log.Println(err.ToJson())
Custom Error
You can create your own Error return string. By default, uhoh will return with format: date | type error | original error | describe error
// Create your own error return value
customError := func(err *Err) string {
return err.Original.Error() + ": " + err.Describe.Error()
}
// Set it to your function
SetDefaultErrorFormatter(customError)
originalErr := errors.New("original error")
describeErr := errors.New("describe error")
err := New(originalErr).SetDescribe(describeErr).SetType(uhoh.ErrGeneral)
fmt.Printf("%s", err.Error())
// Output:
// original error: describe error
Set Date
The date is set to the current date and time. If you want to set the date to a specific date, you can use the SetDate
function.
// Errors
originalErr := errors.New("original error")
err := New(originalErr)
err.SetDate(time.Date(2021, time.Month(9), 12, 1, 20, 30, 0, time.UTC))
fmt.Println(err.Date)
// Output:
// 2021-09-12 01:20:30 +0000 UTC