common

Documentation

Overview

Package common contains common utilities that are shared among other packages. See each sub-package for detail.

Index

• Variables
• func Close(obj interface{}) error
• func CreateObject(ctx context.Context, config interface{}) (interface{}, error)
• func Error2(v interface{}, err error) error
• func GetGOBIN() string
• func GetGOPATH() string
• func GetModuleName(pathToProjectRoot string) (string, error)
• func GetRuntimeEnv(key string) (string, error)
• func Interrupt(obj interface{}) error
• func Must(err error)
• func Must2(v interface{}, err error) interface{}
• func RegisterConfig(config interface{}, configCreator ConfigCreator) error
• type ChainedClosable
  • func (cc ChainedClosable) Close() error
• type Closable
• type ConfigCreator
• type HasType
• type Interruptible
• type Runnable

Variables

var ErrNoClue = errors.New("not enough information for making a decision")

ErrNoClue is for the situation that existing information is not enough to make a decision. For example, Router may return this error when there is no suitable route.

Functions

func Close

func Close(obj interface{}) error

Close closes the obj if it is a Closable.

xray:api:beta

func CreateObject

func CreateObject(ctx context.Context, config interface{}) (interface{}, error)

CreateObject creates an object by its config. The config type must be registered through RegisterConfig().

func Error2

func Error2(v interface{}, err error) error

Error2 returns the err from the 2nd parameter.

func GetGOBIN

func GetGOBIN() string

GetGOBIN returns GOBIN environment variable as a string. It will NOT be empty.

func GetGOPATH

func GetGOPATH() string

GetGOPATH returns GOPATH environment variable as a string. It will NOT be empty.

func GetModuleName

func GetModuleName(pathToProjectRoot string) (string, error)

GetModuleName returns the value of module in `go.mod` file.

func GetRuntimeEnv

func GetRuntimeEnv(key string) (string, error)

GetRuntimeEnv returns the value of runtime environment variable, that is set by running following command: `go env -w key=value`.

func Interrupt

func Interrupt(obj interface{}) error

Interrupt calls Interrupt() if object implements Interruptible interface, or Close() if the object implements Closable interface.

xray:api:beta

func Must

func Must(err error)

Must panics if err is not nil.

func Must2

func Must2(v interface{}, err error) interface{}

Must2 panics if the second parameter is not nil, otherwise returns the first parameter.

func RegisterConfig

func RegisterConfig(config interface{}, configCreator ConfigCreator) error

RegisterConfig registers a global config creator. The config can be nil but must have a type.

Types

type ChainedClosable

type ChainedClosable []Closable

ChainedClosable is a Closable that consists of multiple Closable objects.

func (ChainedClosable) Close

func (cc ChainedClosable) Close() error

Close implements Closable.

type Closable

type Closable interface {
	// Close release all resources used by this object, including goroutines.
	Close() error
}

Closable is the interface for objects that can release its resources.

xray:api:beta

type ConfigCreator

type ConfigCreator func(ctx context.Context, config interface{}) (interface{}, error)

ConfigCreator is a function to create an object by a config.

type HasType

type HasType interface {
	// Type returns the type of the object.
	// Usually it returns (*Type)(nil) of the object.
	Type() interface{}
}

HasType is the interface for objects that knows its type.

type Interruptible

type Interruptible interface {
	Interrupt()
}

Interruptible is an interface for objects that can be stopped before its completion.

xray:api:beta

type Runnable

type Runnable interface {
	// Start starts the runnable object. Upon the method returning nil, the object begins to function properly.
	Start() error

	Closable
}

Runnable is the interface for objects that can start to work and stop on demand.