package derror
import "github.com/Diarkis/diarkis/derror"
Package derror ▷
Diarkis error package allows the server to send byte array encoded error structure that contains an error code and an error message for the client.
Error Code
An error code is sent from the server to the client along with an error message as a string. This is enabled when the server is started with DIARKIS_USE_STRUCT_ERR=true env. An error code is a uint16 numeric value.
▶︎ Error Type
[ 0 ]0000 ↑ This here describes the type of error.
The first digit is used to describe the type of error. The valid error types are listed below.
| Description | Code | |
| Not Allowed | The operation is not allowed to be performed. | 1 |
| Condition Failed | The operation and given parameters do not satisfy conditions to perform the command operation successfully. | 2 |
| Invalid Parameters | At least one of the given parameters is not valid. | 3 |
| Not Found | Intended entity (such as a room) is not found. | 4 |
| Server Error | The execution of the command failed due to errors caused by the server. | 5 |
Server Response Status
A server response comes with a response status code. There are three status codes as follows:
When DIARKIS_USE_STRUCT_ERR=true env is used, the value of Bad and Error response code changes to indicate the use of struct error.
| Status | Description | Code | Code With Struct Error |
| OK | The command was successfully executed. | 1 | |
| Bad | The command execution failed because of invalid command invocation such as invalid parameters etc. | 4 | 40 |
| Error | The command failed to execute due to server failure. | 5 | 50 |
Usage
derror is meant to be used as errors sent from the server to the client as a response of a command.
// Create a response error data []byte.
// This error response can be decoded and converted into a struct
// with an error message and error code on the client.
errMessage := err.Error()
// We pass 0 here as an example.
// This value here is reserved for custom error code to further describe error details.
errCode := derror.ConditionFailed(0)
errForResponse := derror.ErrData(errMessage, errCode)
// Send the error response to the client
reliable := true
userData.ServerRespond(errForResponse, ver, cmd, server.Bad, reliable)
Index
- func ConditionFailed(customCode uint16) uint16
- func ErrData(message string, code uint16) []byte
- func Internal(customCode uint16) uint16
- func InvalidParameter(customCode uint16) uint16
- func IsStructErrEnabled() bool
- func NotAllowed(customCode uint16) uint16
- func NotFound(customCode uint16) uint16
- type Error
Functions
func ConditionFailed
func ConditionFailed(customCode uint16) uint16
ConditionFailed returns an error code as Condition Failed with the custom code ranging from 0 to 5535.
Important
If customCode given exceeds 5535, it will forced to be 5535.
Example:
errorCode := ecode.ErrConditionFailed(100)
// errorCode = 20100
fmt.Println(errorCode)
func ErrData
func ErrData(message string, code uint16) []byte
ErrData returns either a UTF8 string message as a byte array or structured error data as a byte array.
Important
This is meant to be sent to the client.
In order to use structured error data, use DIARKIS_USE_STRUCT_ERR env.
func Internal
func Internal(customCode uint16) uint16
Internal returns an error code as internal server failure with the custom code ranging from 0 to 5535.
Important
If customCode given exceeds 5535, it will forced to be 5535.
Example:
errorCode := ecode.ErrInternal(100)
// errorCode = 50100
fmt.Println(errorCode)
func InvalidParameter
func InvalidParameter(customCode uint16) uint16
InvalidParameter returns an error code as Invalid Parameter with the custom code ranging from 0 to 5535.
Important
If customCode given exceeds 5535, it will forced to be 5535.
Example:
errorCode := ecode.ErrInvalidParameter(100)
// errorCode = 30100
fmt.Println(errorCode)
func IsStructErrEnabled
func IsStructErrEnabled() bool
IsStructErrEnabled returns true if DIARKIS_USE_STRUCT_ERR=true env is used.
func NotAllowed
func NotAllowed(customCode uint16) uint16
NotAllowed returns an error code as Not Allowed with the custom code ranging from 0 to 5535.
Important
If customCode given exceeds 5535, it will forced to be 5535.
Example:
errorCode := ecode.ErrNotAllowed(100)
// errorCode = 10100
fmt.Println(errorCode)
func NotFound
func NotFound(customCode uint16) uint16
NotFound returns an error code as Not Found with the custom code ranging from 0 to 5535.
Important
If customCode given exceeds 5535, it will forced to be 5535.
Example:
errorCode := ecode.ErrNotFound(100)
// errorCode = 40100
fmt.Println(errorCode)
Types
type Error
type Error struct { }
Error is the custom error data
func New
func New(message string, code uint16) *Error
New creates a new error data.
Error Data Byte Array Structure
┌────────────┬───────────────┐ │ Error Code │ Error Message │ ├────────────┼───────────────┤ | uint16 │ string │ ├────────────┼───────────────┤ | 2 bytes │ variable │ └────────────┴───────────────┘
func ToError
func ToError(bytes []byte) *Error
ToError converts error bytes to an error data
func (*Error) Bytes
func (e *Error) Bytes() []byte
Bytes returns the byte array for the client.
Note
Encoded byte array does NOT include error stacktrace.
func (*Error) Code
func (e *Error) Code() uint16
Code returns the error code
func (*Error) Message
func (e *Error) Message() string
Message returns the error message
func (*Error) StackTrace
func (e *Error) StackTrace() string
StackTrace return a string of stacktrace.
Note
Decoded *Error from encoded byte array will have an empty stacktrace string.