frostfs-sdk-go/ns/nns.go
Marina Biryukova 0886d80083 [#69] Add close for nns.Dial
Signed-off-by: Marina Biryukova <m.biryukova@yadro.com>
2023-07-31 11:05:26 +03:00

169 lines
5 KiB
Go

package ns
import (
"context"
"errors"
"fmt"
"net/url"
"git.frostfs.info/TrueCloudLab/frostfs-contract/nns"
"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container"
cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
"github.com/nspcc-dev/neo-go/pkg/core/state"
"github.com/nspcc-dev/neo-go/pkg/encoding/address"
"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
"github.com/nspcc-dev/neo-go/pkg/rpcclient"
"github.com/nspcc-dev/neo-go/pkg/rpcclient/invoker"
"github.com/nspcc-dev/neo-go/pkg/rpcclient/unwrap"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
)
// multiSchemeClient unites invoker.RPCInvoke and common interface of
// rpcclient.Client and rpcclient.WSClient.
type multiSchemeClient interface {
invoker.RPCInvoke
// Init turns client to "ready-to-work" state.
Init() error
// Close closes connections.
Close()
// GetContractStateByID returns state of the NNS contract on 1 input.
GetContractStateByID(int32) (*state.Contract, error)
}
// NNS looks up FrostFS names using Neo Name Service.
//
// Instances are created with a variable declaration. Before work, the connection
// to the NNS server MUST be established using Dial method.
type NNS struct {
nnsContract util.Uint160
client multiSchemeClient
invoker interface {
Call(contract util.Uint160, operation string, params ...any) (*result.Invoke, error)
}
}
// Dial connects to the address of the NNS server. If fails, the instance
// MUST NOT be used.
//
// If URL address scheme is 'ws' or 'wss', then WebSocket protocol is used,
// otherwise HTTP.
func (n *NNS) Dial(address string) error {
var err error
uri, err := url.Parse(address)
if err == nil && (uri.Scheme == "ws" || uri.Scheme == "wss") {
n.client, err = rpcclient.NewWS(context.Background(), address, rpcclient.WSOptions{})
if err != nil {
return fmt.Errorf("create Neo WebSocket client: %w", err)
}
} else {
n.client, err = rpcclient.New(context.Background(), address, rpcclient.Options{})
if err != nil {
return fmt.Errorf("create Neo HTTP client: %w", err)
}
}
if err = n.client.Init(); err != nil {
return fmt.Errorf("initialize Neo client: %w", err)
}
nnsContract, err := n.client.GetContractStateByID(1)
if err != nil {
return fmt.Errorf("get NNS contract state: %w", err)
}
n.invoker = invoker.New(n.client, nil)
n.nnsContract = nnsContract.Hash
return nil
}
// Close closes connections of multiSchemeClient.
func (n *NNS) Close() {
n.client.Close()
}
// ResolveContainerDomain looks up for NNS TXT records for the given container domain
// by calling `resolve` method of NNS contract. Returns the first record which represents
// valid container ID in a string format. Otherwise, returns an error.
//
// ResolveContainerDomain MUST NOT be called before successful Dial.
//
// See also https://docs.neo.org/docs/en-us/reference/nns.html.
func (n *NNS) ResolveContainerDomain(domain container.Domain) (cid.ID, error) {
item, err := unwrap.Item(n.invoker.Call(n.nnsContract, "resolve",
domain.Name()+"."+domain.Zone(), int64(nns.TXT),
))
if err != nil {
return cid.ID{}, fmt.Errorf("contract invocation: %w", err)
}
if _, ok := item.(stackitem.Null); !ok {
arr, ok := item.Value().([]stackitem.Item)
if !ok {
// unexpected for types from stackitem package
return cid.ID{}, errors.New("invalid cast to stack item slice")
}
var id cid.ID
for i := range arr {
bs, err := arr[i].TryBytes()
if err != nil {
return cid.ID{}, fmt.Errorf("convert array item to byte slice: %w", err)
}
err = id.DecodeString(string(bs))
if err == nil {
return id, nil
}
}
}
return cid.ID{}, errNotFound
}
// ResolveContractHash looks up for NNS TXT records for the given container domain
// by calling `resolve` method of NNS contract. Returns the first record which represents
// valid contract hash 20 bytes long unsigned integer. Otherwise, returns an error.
//
// ResolveContractHash MUST NOT be called before successful Dial.
//
// See also https://docs.neo.org/docs/en-us/reference/nns.html.
func (n *NNS) ResolveContractHash(domain container.Domain) (util.Uint160, error) {
item, err := unwrap.Item(n.invoker.Call(n.nnsContract, "resolve",
domain.Name()+"."+domain.Zone(), int64(nns.TXT),
))
if err != nil {
return util.Uint160{}, fmt.Errorf("contract invocation: %w", err)
}
if _, ok := item.(stackitem.Null); !ok {
arr, ok := item.Value().([]stackitem.Item)
if !ok {
// unexpected for types from stackitem package
return util.Uint160{}, errors.New("invalid cast to stack item slice")
}
for i := range arr {
recordValue, err := arr[i].TryBytes()
if err != nil {
return util.Uint160{}, fmt.Errorf("convert array item to byte slice: %w", err)
}
strRecordValue := string(recordValue)
scriptHash, err := address.StringToUint160(strRecordValue)
if err == nil {
return scriptHash, nil
}
scriptHash, err = util.Uint160DecodeStringLE(strRecordValue)
if err == nil {
return scriptHash, nil
}
}
}
return util.Uint160{}, errNotFound
}