chore: move token example to nep5 as package name (CityOfZion/neo-storm#19)

* feat: add token example

* feat: code splitted package

* feat: use updated apis

* chore: change token namespace to nep5

* chore: add transfer event and readme updates

Imported from CityOfZion/neo-storm (63ec2d7dc23a60f128a8b383ceda1eaa15d919c1).
This commit is contained in:
Jeroen Peeters 2018-08-22 18:49:30 +02:00 committed by Roman Khimov
parent b3037cd598
commit 1f8ccdba16
4 changed files with 118 additions and 6 deletions

View file

@ -1,7 +1,7 @@
package token_contract
import (
"token"
"nep5"
"github.com/CityOfZion/neo-storm/interop/storage"
"github.com/CityOfZion/neo-storm/interop/util"
@ -15,8 +15,8 @@ const (
var owner = util.FromAddress("AK2nJJpJr6o664CWJKi1QRXjqeic2zRp8y")
// CreateToken initializes the Token Interface for the Smart Contract to operate with
func CreateToken() token.Token {
return token.Token{
func CreateToken() nep5.Token {
return nep5.Token{
Name: "Awesome NEO Token",
Symbol: "ANT",
Decimals: decimals,

112
examples/token/vendor/nep5/nep5.go vendored Normal file
View file

@ -0,0 +1,112 @@
package nep5
import (
"github.com/CityOfZion/neo-storm/interop/engine"
"github.com/CityOfZion/neo-storm/interop/runtime"
"github.com/CityOfZion/neo-storm/interop/storage"
)
// Token holds all token info
type Token struct {
// Token name
Name string
// Ticker symbol
Symbol string
// Amount of decimals
Decimals int
// Token owner address
Owner []byte
// Total tokens * multiplier
TotalSupply int
// Storage key for circulation value
CirculationKey string
}
// GetSupply gets the token totalSupply value from VM storage
func (t Token) GetSupply(ctx storage.Context) interface{} {
return storage.Get(ctx, t.CirculationKey)
}
// BalanceOf gets the token balance of a specific address
func (t Token) BalanceOf(ctx storage.Context, hodler []byte) interface{} {
return storage.Get(ctx, hodler)
}
// Transfer token from one user to another
func (t Token) Transfer(ctx storage.Context, from []byte, to []byte, amount int) bool {
amountFrom := t.CanTransfer(ctx, from, to, amount)
if amountFrom == -1 {
return false
}
if amountFrom == 0 {
storage.Delete(ctx, from)
}
if amountFrom > 0 {
diff := amountFrom - amount
storage.Put(ctx, from, diff)
}
amountTo := storage.Get(ctx, to).(int)
totalAmountTo := amountTo + amount
storage.Put(ctx, to, totalAmountTo)
runtime.Notify("transfer", from, to, amount)
return true
}
// CanTransfer returns the amount it can transfer
func (t Token) CanTransfer(ctx storage.Context, from []byte, to []byte, amount int) int {
if len(to) != 20 && !IsUsableAddress(from) {
return -1
}
amountFrom := storage.Get(ctx, from).(int)
if amountFrom < amount {
return -1
}
// Tell Transfer the result is equal - special case since it uses Delete
if amountFrom == amount {
return 0
}
// return amountFrom value back to Transfer, reduces extra Get
return amountFrom
}
// IsUsableAddress checks if the sender is either the correct NEO address or SC address
func IsUsableAddress(addr []byte) bool {
if len(addr) == 20 {
if runtime.CheckWitness(addr) {
return true
}
// Check if a smart contract is calling scripthash
callingScriptHash := engine.GetCallingScriptHash()
if EqualAddresses(callingScriptHash, addr) {
return true
}
}
return false
}
// EqualAddresses compares two addresses if they're equal
// also returns false if one of the two - or both - aren't actual addresses
func EqualAddresses(a []byte, b []byte) bool {
aLen := len(a)
bLen := len(b)
if aLen != bLen || aLen != 20 || bLen != 20 {
return false
}
for i := 0; i < aLen; i++ {
if a[i] != b[i] {
return false
}
}
return true
}

View file

@ -12,7 +12,7 @@ func CheckWitness(hash []byte) bool {
func Log(message string) {}
// Notify an event to the VM.
func Notify(arg interface{}) int {
func Notify(arg ...interface{}) int {
return 0
}
@ -42,7 +42,7 @@ func Serialize(item interface{}) []byte {
return nil
}
// Deserializes an item from a bytearray.
// Deserialize an item from a bytearray.
func Deserialize(b []byte) interface{} {
return nil
}

View file

@ -23,7 +23,7 @@ func TestExamplesFolder(t *testing.T) {
t.Fatal(err)
}
if len(infos) > 1 {
t.Fatal("detected smart contract folder with more then 1 contract file")
t.Fatal("detected smart contract folder with more than 1 contract file")
}
if len(infos) == 0 {
t.Fatal("detected smart contract folder with no contract in it")