status-go/services/wallet/balance.go

75 lines
2.0 KiB
Go

package wallet
import (
"context"
"sync"
"time"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/accounts/abi/bind"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/ethclient"
"github.com/ethereum/go-ethereum/log"
"github.com/status-im/status-go/services/wallet/ierc20"
)
var requestTimeout = 20 * time.Second
// GetTokensBalances takes list of accounts and tokens and returns mapping of token balances for each account.
func GetTokensBalances(parent context.Context, client *ethclient.Client, accounts, tokens []common.Address) (map[common.Address]map[common.Address]*hexutil.Big, error) {
var (
group = NewAtomicGroup(parent)
mu sync.Mutex
response = map[common.Address]map[common.Address]*hexutil.Big{}
)
// requested current head to request balance on the same block number
ctx, cancel := context.WithTimeout(parent, requestTimeout)
header, err := client.HeaderByNumber(ctx, nil)
cancel()
if err != nil {
return nil, err
}
for _, token := range tokens {
caller, err := ierc20.NewIERC20Caller(token, client)
token := token
if err != nil {
return nil, err
}
for _, account := range accounts {
// Why we are doing this?
account := account
group.Add(func(parent context.Context) error {
ctx, cancel := context.WithTimeout(parent, requestTimeout)
balance, err := caller.BalanceOf(&bind.CallOpts{
BlockNumber: header.Number,
Context: ctx,
}, account)
cancel()
// We don't want to return an error here and prevent
// the rest from completing
if err != nil {
log.Error("can't fetch erc20 token balance", "account", account, "token", token, "error", err)
return nil
}
mu.Lock()
_, exist := response[account]
if !exist {
response[account] = map[common.Address]*hexutil.Big{}
}
response[account][token] = balance
mu.Unlock()
return nil
})
}
}
select {
case <-group.WaitAsync():
case <-parent.Done():
return nil, parent.Err()
}
return response, group.Error()
}