utils

Documentation

Overview

Package utils is used for the common functions for dealing with conversion to and from hex, bytes, and strings, formatting time.

Index

• Constants
• Variables
• func AddHexPrefix(str string) string
• func CheckPasswordHash(password, hash string) bool
• func CoerceInterfaceMapToStringMap(in interface{}) (interface{}, error)
• func DecodeEthereumTx(hex string) (types.Transaction, error)
• func EVMHexNumber(val interface{}) string
• func EVMSignedHexNumber(val *big.Int) (string, error)
• func EncodeTxToHex(tx *types.Transaction) (string, error)
• func FileExists(name string) bool
• func FormatJSON(v interface{}) ([]byte, error)
• func HashPassword(password string) (string, error)
• func HexConcat(strs ...string) string
• func HexToBytes(strs ...string) ([]byte, error)
• func HexToString(hex string) (string, error)
• func HexToUint64(hex string) (uint64, error)
• func ISO8601UTC(t time.Time) string
• func IsEmptyAddress(addr common.Address) bool
• func IsHex(str string) bool
• func Keccak256(in []byte) ([]byte, error)
• func MaxUint64(uints ...uint64) uint64
• func NewBytes32ID() string
• func NormalizedJSON(val []byte) (string, error)
• func NullISO8601UTC(t null.Time) string
• func ParseUintHex(hex string) (*big.Int, error)
• func RemoveHexPrefix(str string) string
• func RemoveQuotes(input []byte) []byte
• func StringToHex(in string) string
• func StripBearer(authorizationStr string) string
• func ToFilterArg(q ethereum.FilterQuery) interface{}
• func ToFilterQueryFor(fromBlock *big.Int, addresses []common.Address) ethereum.FilterQuery
• func Uint64ToHex(i uint64) string
• func WithoutZeroAddresses(addresses []common.Address) []common.Address
• type BackoffSleeper
  • func NewBackoffSleeper() BackoffSleeper
  • func (bs BackoffSleeper) Duration() time.Duration
  • func (bs BackoffSleeper) Sleep()
• type ConstantSleeper
  • func NewConstantSleeper(d time.Duration) ConstantSleeper
  • func (cs ConstantSleeper) Duration() time.Duration
  • func (cs ConstantSleeper) Sleep()
• type Sleeper

Constants

const (
	// HumanTimeFormat is the predefined layout for use in Time.Format and time.Parse
	HumanTimeFormat = "2006-01-02 15:04:05 MST"
	// EVMWordByteLen the length of an EVM Word Byte
	EVMWordByteLen = 32
	// EVMWordHexLen the length of an EVM Word Hex
	EVMWordHexLen = EVMWordByteLen * 2
)

Variables

var ZeroAddress = common.Address{}

ZeroAddress is an empty address, otherwise in Ethereum as 0x0000000000000000000000000000000000000000

Functions

func AddHexPrefix

func AddHexPrefix(str string) string

AddHexPrefix adds the previx (0x) to a given hex string.

func CheckPasswordHash

func CheckPasswordHash(password, hash string) bool

CheckPasswordHash wraps around bcrypt.CompareHashAndPassword for a friendlier API.

func CoerceInterfaceMapToStringMap

func CoerceInterfaceMapToStringMap(in interface{}) (interface{}, error)

CoerceInterfaceMapToStringMap converts map[interface{}]interface{} (interface maps) to map[string]interface{} (string maps) and []interface{} with interface maps to string maps. Relevant when serializing between CBOR and JSON.

func DecodeEthereumTx

func DecodeEthereumTx(hex string) (types.Transaction, error)

DecodeEthereumTx takes an RLP hex encoded Ethereum transaction and returns a Transaction struct with all the fields accessible.

func EVMHexNumber

func EVMHexNumber(val interface{}) string

EVMHexNumber formats a number as a 32 byte hex string.

func EVMSignedHexNumber

func EVMSignedHexNumber(val *big.Int) (string, error)

EVMSignedHexNumber formats a number as a 32 byte hex string Twos compliment representation if a minus number

func EncodeTxToHex

func EncodeTxToHex(tx *types.Transaction) (string, error)

EncodeTxToHex converts the given Ethereum Transaction type and returns its hex-value string.

func FileExists

func FileExists(name string) bool

FileExists returns true if a file at the passed string exists.

func FormatJSON

func FormatJSON(v interface{}) ([]byte, error)

FormatJSON applies indent to format a JSON response.

func HashPassword

func HashPassword(password string) (string, error)

HashPassword wraps around bcrypt.GenerateFromPassword for a friendlier API.

func HexConcat

func HexConcat(strs ...string) string

HexConcat concatenates a given array of strings to return a single string.

func HexToBytes

func HexToBytes(strs ...string) ([]byte, error)

HexToBytes converts the given array of strings and returns bytes.

func HexToString

func HexToString(hex string) (string, error)

HexToString decodes a hex encoded string.

func HexToUint64

func HexToUint64(hex string) (uint64, error)

HexToUint64 converts a given hex string to 64-bit unsigned integer.

func ISO8601UTC

func ISO8601UTC(t time.Time) string

ISO8601UTC formats given time to ISO8601.

func IsEmptyAddress

func IsEmptyAddress(addr common.Address) bool

IsEmptyAddress checks that the address is empty, synonymous with the zero account/address. No logs can come from this address, as there is no contract present there.

See https://stackoverflow.com/questions/48219716/what-is-address0-in-solidity for the more info on the zero address.

func IsHex

func IsHex(str string) bool

IsHex returns true if the string starts with 0x.

func Keccak256

func Keccak256(in []byte) ([]byte, error)

Keccak256 is a simplified interface for the legacy SHA3 implementation that Ethereum uses.

func MaxUint64

func MaxUint64(uints ...uint64) uint64

MaxUint64 finds the maximum value of a list of uint64s.

func NewBytes32ID

func NewBytes32ID() string

NewBytes32ID returns a randomly generated UUID that conforms to Ethereum bytes32.

func NormalizedJSON

func NormalizedJSON(val []byte) (string, error)

NormalizedJSON returns a JSON representation of an object that has been normalized to produce a consistent output for hashing.

NOTE: If this string is unmarshalled again, there is no guarantee that the final representation will be consistent with the string produced by this function due to differences in JSON implementations and information loss. e.g:

JSON does not have a requirement to respect object key ordering.

func NullISO8601UTC

func NullISO8601UTC(t null.Time) string

NullISO8601UTC returns formatted time if valid, empty string otherwise.

func ParseUintHex

func ParseUintHex(hex string) (*big.Int, error)

ParseUintHex parses an unsigned integer out of a hex string.

func RemoveHexPrefix

func RemoveHexPrefix(str string) string

RemoveHexPrefix removes the prefix (0x) of a given hex string.

func RemoveQuotes

func RemoveQuotes(input []byte) []byte

RemoveQuotes removes the first and last character if they are both either " or ', otherwise it is a noop.

func StringToHex

func StringToHex(in string) string

StringToHex converts a standard string to a hex encoded string.

func StripBearer

func StripBearer(authorizationStr string) string

StripBearer removes the 'Bearer: ' prefix from the HTTP Authorization header.

func ToFilterArg

func ToFilterArg(q ethereum.FilterQuery) interface{}

ToFilterArg filters logs with the given FilterQuery https://github.com/ethereum/go-ethereum/blob/762f3a48a00da02fe58063cb6ce8dc2d08821f15/ethclient/ethclient.go#L363

func ToFilterQueryFor

func ToFilterQueryFor(fromBlock *big.Int, addresses []common.Address) ethereum.FilterQuery

ToFilterQueryFor returns a struct that encapsulates desired arguments used to filter event logs.

func Uint64ToHex

func Uint64ToHex(i uint64) string

Uint64ToHex converts the given uint64 value to a hex-value string.

func WithoutZeroAddresses

func WithoutZeroAddresses(addresses []common.Address) []common.Address

WithoutZeroAddresses returns a list of addresses excluding the zero address.

Types

type BackoffSleeper

type BackoffSleeper struct {
	*backoff.Backoff
}

BackoffSleeper is a counter to assist with reattempts.

func NewBackoffSleeper

func NewBackoffSleeper() BackoffSleeper

NewBackoffSleeper returns a BackoffSleeper that is configured to sleep for 1 second minimum, and 10 seconds maximum.

func (BackoffSleeper) Duration

func (bs BackoffSleeper) Duration() time.Duration

Duration returns the current duration value.

func (BackoffSleeper) Sleep

func (bs BackoffSleeper) Sleep()

Sleep waits for the given duration before reattempting.

type ConstantSleeper

type ConstantSleeper struct {
	Sleeper
	// contains filtered or unexported fields
}

ConstantSleeper is to assist with reattempts with the same sleep duration.

func NewConstantSleeper

func NewConstantSleeper(d time.Duration) ConstantSleeper

NewConstantSleeper returns a ConstantSleeper that is configured to sleep for a constant duration based on the input.

func (ConstantSleeper) Duration

func (cs ConstantSleeper) Duration() time.Duration

Duration returns the duration value.

func (ConstantSleeper) Sleep

func (cs ConstantSleeper) Sleep()

Sleep waits for the given duration before reattempting.

type Sleeper

type Sleeper interface {
	Reset()
	Sleep()
	Duration() time.Duration
}

Sleeper interface is used for tasks that need to be done on some interval, excluding Cron, like reconnecting.