util

README

util

This is a package full of helper functions I've written over the years to make writing in golang a little easier.

Most things have tests.

It is kind of a junk drawer so unless you absolutely need to, maybe don't add to it.

Documentation

Overview

Package util is the junk drawer of helper functions. It should not be expanded unless necessary.

Index

• Constants
• Variables
• func AnyError(err ...error) error
• func GetIP(r *http.Request) string
• func GetParamByName(r *http.Request, name string) string
• func OptionalBool(value bool) *bool
• func OptionalDuration(value time.Duration) *time.Duration
• func OptionalFloat32(value float32) *float32
• func OptionalFloat64(value float64) *float64
• func OptionalInt(value int) *int
• func OptionalInt16(value int16) *int16
• func OptionalInt32(value int32) *int32
• func OptionalInt64(value int64) *int64
• func OptionalString(value string) *string
• func OptionalTime(value time.Time) *time.Time
• func OptionalUInt(value uint) *uint
• func OptionalUInt16(value uint16) *uint16
• func OptionalUInt64(value uint64) *uint64
• func OptionalUInt8(value uint8) *uint8
• func RandomProvider() *rand.Rand
• func WriteJSON(w http.ResponseWriter, statusCode int, response interface{}) (int, error)
• type AnsiColorCode
  • func (acc AnsiColorCode) Apply(text string) string
• type Boolean
  • func (bit Boolean) AsBool() bool
  • func (bit *Boolean) UnmarshalJSON(data []byte) error
• type EncryptedStream
• type GCMEncryptionResult
• type PatchStringer
• type Patcher
• type ReadChunkHandler
• type ReadLineHandler
• type StreamDecrypter
  • func NewStreamDecrypter(key []byte, meta *EncryptedStream, cipherText io.Reader) (*StreamDecrypter, error)
  • func (s *StreamDecrypter) Authenticate() error
  • func (s *StreamDecrypter) Read(p []byte) (int, error)
• type StreamEncrypter
  • func NewStreamEncrypter(key []byte, plainText io.Reader) (*StreamEncrypter, error)
  • func (s *StreamEncrypter) Meta() *EncryptedStream
  • func (s *StreamEncrypter) Read(p []byte) (int, error)

Constants

const (
	// Kilobyte represents the bytes in a kilobyte.
	Kilobyte int64 = 1 << 10
	// Megabyte represents the bytes in a megabyte.
	Megabyte int64 = Kilobyte << 10
	// Gigabyte represents the bytes in a gigabyte.
	Gigabyte int64 = Megabyte << 10
)

const (
	// FieldTagEnv is the struct tag for what environment variable to use to populate a field.
	FieldTagEnv = "env"
	// FieldFlagCSV is a field tag flag (say that 10 times fast).
	FieldFlagCSV = "csv"
	// FieldFlagBase64 is a field tag flag (say that 10 times fast).
	FieldFlagBase64 = "base64"
	// FieldFlagBytes is a field tag flag (say that 10 times fast).
	FieldFlagBytes = "bytes"
)

PatchStrings options.

const (
	// StringEmpty is the empty string
	StringEmpty string = ""

	// RuneSpace is a single rune representing a space.
	RuneSpace rune = ' '

	// RuneNewline is a single rune representing a newline.
	RuneNewline rune = '\n'

	// LowerA is the ascii int value for 'a'
	LowerA uint = uint('a')
	// LowerZ is the ascii int value for 'z'
	LowerZ uint = uint('z')
)

const (

	// Epsilon represents the minimum amount of relevant delta we care about.
	Epsilon = 0.00000001
)

const (
	// ErrBooleanUnmarshal is an exception class.
	ErrBooleanUnmarshal = exception.Class("cannot unmarshal boolean")
)

Variables

var (

	// LowerLetters is a runset of lowercase letters.
	LowerLetters = []rune("abcdefghijklmnopqrstuvwxyz")

	// UpperLetters is a runset of uppercase letters.
	UpperLetters = []rune("ABCDEFGHIJKLMNOPQRSTUVWXYZ")

	// Letters is a runset of both lower and uppercase letters.
	Letters = append(LowerLetters, UpperLetters...)

	// Numbers is a runset of numeric characters.
	Numbers = []rune("0123456789")

	// LettersAndNumbers is a runset of letters and numeric characters.
	LettersAndNumbers = append(Letters, Numbers...)

	// Symbols is a runset of symbol characters.
	Symbols = []rune(`!@#$%^&*()_+-=[]{}\|:;`)

	// LettersNumbersAndSymbols is a runset of letters, numbers and symbols.
	LettersNumbersAndSymbols = append(LettersAndNumbers, Symbols...)
)

var Base64 base64Util

Base64 is a namespace singleton for (2) methods.

var (
	// BitFlag is a namespace for bitflag functions.
	BitFlag = bitFlag{}
)

var Coalesce coalesceUtil

Coalesce is a set of utilities for coalesced values.

var (
	// Combinatorics is a namespace containing combinatoric functions.
	Combinatorics = combinatorics{}
)

var Crypto = cryptoUtil{}

Crypto is a namespace for crypto related functions.

var File = &fileUtil{}

File contains helper functions for files.

var Format formatUtil

Format is a singleton namespace with utilties for formatting common values.

var GCM = gcmUtil{}

GCM is a namespace for gcm related utility functions

var (
	// GZip is a namespace for gzip utilities.
	GZip = gzipUtil{}
)

var (
	// JSON is a namespace for json utils.
	JSON = jsonUtil{}
)

var (
	// Math is a namespace for math utilities.
	Math = mathUtil{}
)

var (
	// Parallel contains parallel utils.
	Parallel = parallelUtil{}
)

var Parse = new(parseUtil)

Parse contains utilities to parse strings.

var (
	// Reflection is a namespace for reflection utilities.
	Reflection = reflectionUtil{}
)

var Sequence sequenceUtil

Sequence is a namespace singleton for sequence utilities.

var (
	// String is a namesapce for string utility functions.
	String = stringUtil{}
)

var Ternary = ternaryUtil{}

Ternary is a collection of ternary functions.

var (
	// Time is a namespace for time utility functions.
	Time = timeUtil{}
)

var (
	// Vector is a namespace for vector functions.
	Vector = vectorUtil{}
)

var (
	// XML is a namespace for xml utilities.
	XML = xmlUtil{}
)

Functions

func AnyError

func AnyError(err ...error) error

AnyError returns any variadic error that is not nil.

func GetIP

func GetIP(r *http.Request) string

GetIP gets the origin/client ip for a request. X-FORWARDED-FOR is checked. If multiple IPs are included the first one is returned X-REAL-IP is checked. If multiple IPs are included the first one is returned Finally r.RemoteAddr is used Only benevolent services will allow access to the real IP

func GetParamByName

func GetParamByName(r *http.Request, name string) string

GetParamByName returns a named parameter from either the querystring, the headers, the cookies, the form or the post form of a request.

func OptionalBool

func OptionalBool(value bool) *bool

OptionalBool returns a pointer to a value

func OptionalDuration

func OptionalDuration(value time.Duration) *time.Duration

OptionalDuration returns a pointer to a value

func OptionalFloat32

func OptionalFloat32(value float32) *float32

OptionalFloat32 returns a pointer to a value

func OptionalFloat64

func OptionalFloat64(value float64) *float64

OptionalFloat64 returns a pointer to a value

func OptionalInt

func OptionalInt(value int) *int

OptionalInt returns a pointer to a value

func OptionalInt16

func OptionalInt16(value int16) *int16

OptionalInt16 returns a pointer to a value

func OptionalInt32

func OptionalInt32(value int32) *int32

OptionalInt32 returns a pointer to a value

func OptionalInt64

func OptionalInt64(value int64) *int64

OptionalInt64 returns a pointer to a value

func OptionalString

func OptionalString(value string) *string

OptionalString returns a pointer to a value

func OptionalTime

func OptionalTime(value time.Time) *time.Time

OptionalTime returns a pointer to a value

func OptionalUInt

func OptionalUInt(value uint) *uint

OptionalUInt returns a pointer to a value

func OptionalUInt16

func OptionalUInt16(value uint16) *uint16

OptionalUInt16 returns a pointer to a value

func OptionalUInt64

func OptionalUInt64(value uint64) *uint64

OptionalUInt64 returns a pointer to a value

func OptionalUInt8

func OptionalUInt8(value uint8) *uint8

OptionalUInt8 returns a pointer to a value

func RandomProvider

func RandomProvider() *rand.Rand

RandomProvider returns a centralized random provider, seeded with time.Now().UnixNano().

func WriteJSON

func WriteJSON(w http.ResponseWriter, statusCode int, response interface{}) (int, error)

WriteJSON writes an object to a response as json.

Types

type AnsiColorCode

type AnsiColorCode string

AnsiColorCode represents an ansi color code fragment.

const (
	// ColorBlack is the posix escape code fragment for black.
	ColorBlack AnsiColorCode = "30m"

	// ColorRed is the posix escape code fragment for red.
	ColorRed AnsiColorCode = "31m"

	// ColorGreen is the posix escape code fragment for green.
	ColorGreen AnsiColorCode = "32m"

	// ColorYellow is the posix escape code fragment for yellow.
	ColorYellow AnsiColorCode = "33m"

	// ColorBlue is the posix escape code fragment for blue.
	ColorBlue AnsiColorCode = "34m"

	// ColorPurple is the posix escape code fragement for magenta (purple)
	ColorPurple AnsiColorCode = "35m"

	// ColorCyan is the posix escape code fragement for cyan.
	ColorCyan AnsiColorCode = "36m"

	// ColorWhite is the posix escape code fragment for white.
	ColorWhite AnsiColorCode = "37m"

	// ColorLightBlack is the posix escape code fragment for black.
	ColorLightBlack AnsiColorCode = "90m"

	// ColorLightRed is the posix escape code fragment for red.
	ColorLightRed AnsiColorCode = "91m"

	// ColorLightGreen is the posix escape code fragment for green.
	ColorLightGreen AnsiColorCode = "92m"

	// ColorLightYellow is the posix escape code fragment for yellow.
	ColorLightYellow AnsiColorCode = "93m"

	// ColorLightBlue is the posix escape code fragment for blue.
	ColorLightBlue AnsiColorCode = "94m"

	// ColorLightPurple is the posix escape code fragement for magenta (purple)
	ColorLightPurple AnsiColorCode = "95m"

	// ColorLightCyan is the posix escape code fragement for cyan.
	ColorLightCyan AnsiColorCode = "96m"

	// ColorLightWhite is the posix escape code fragment for white.
	ColorLightWhite AnsiColorCode = "97m"

	// ColorGray is an alias to ColorLightWhite to preserve backwards compatibility.
	ColorGray AnsiColorCode = ColorLightBlack

	// ColorReset is the posix escape code fragment to reset all formatting.
	ColorReset AnsiColorCode = "0m"
)

func (AnsiColorCode) Apply

func (acc AnsiColorCode) Apply(text string) string

Apply returns a string with the color code applied.

type Boolean

type Boolean bool

Boolean is a type alias for bool that can be unmarshaled from 0|1, true|false etc.

var (
	// BooleanTrue represents a true value for a boolean.
	BooleanTrue Boolean = true

	// BooleanFalse represents a false value for a boolean.
	BooleanFalse Boolean = false
)

func (Boolean) AsBool

func (bit Boolean) AsBool() bool

AsBool returns the stdlib bool value for the boolean.

func (*Boolean) UnmarshalJSON

func (bit *Boolean) UnmarshalJSON(data []byte) error

UnmarshalJSON unmarshals the boolean from json.

type EncryptedStream

type EncryptedStream struct {
	// IV is the initial value for the crypto function
	IV []byte
	// Hash is the sha256 hmac of the stream
	Hash []byte
}

EncryptedStream is metadata about an encrypted stream

type GCMEncryptionResult

type GCMEncryptionResult struct {
	CipherText []byte
	Nonce      []byte
}

GCMEncryptionResult is a struct for a gcm encryption result

type PatchStringer

type PatchStringer interface {
	PatchStrings(map[string]string) error
}

PatchStringer is a type that handles unmarshalling a map of strings into itself.

type Patcher

type Patcher interface {
	Patch(map[string]interface{}) error
}

Patcher describes an object that can be patched with raw values.

type ReadChunkHandler

type ReadChunkHandler func(line []byte) error

ReadChunkHandler is a receiver for a chunk of a file.

type ReadLineHandler

type ReadLineHandler func(line string) error

ReadLineHandler is a receiver for a line of a file.

type StreamDecrypter

type StreamDecrypter struct {
	// contains filtered or unexported fields
}

StreamDecrypter is a decrypter for a stream of data with authentication

func NewStreamDecrypter

func NewStreamDecrypter(key []byte, meta *EncryptedStream, cipherText io.Reader) (*StreamDecrypter, error)

NewStreamDecrypter creates a new stream decrypter

func (*StreamDecrypter) Authenticate

func (s *StreamDecrypter) Authenticate() error

Authenticate verifys that the hash of the stream is correct. This should only be called after processing is finished

func (*StreamDecrypter) Read

func (s *StreamDecrypter) Read(p []byte) (int, error)

Read reads bytes from the underlying reader and then decrypts them

type StreamEncrypter

type StreamEncrypter struct {
	// contains filtered or unexported fields
}

StreamEncrypter is an encrypter for a stream of data with authentication

func NewStreamEncrypter

func NewStreamEncrypter(key []byte, plainText io.Reader) (*StreamEncrypter, error)

NewStreamEncrypter creates a new stream encrypter

func (*StreamEncrypter) Meta

func (s *StreamEncrypter) Meta() *EncryptedStream

Meta returns the encrypted stream metadata for use in decrypting. This should only be called after the stream is finished

func (*StreamEncrypter) Read

func (s *StreamEncrypter) Read(p []byte) (int, error)

Read encrypts the bytes of the inner reader and places them into p