[#179] resolver: Refactor and document the package
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>remotes/fyrchik/split-info-format
Leonard Lyubich
LeL
parent
c961aea144
commit
146fc4f07a
|
|
@ -1,41 +1,35 @@
|
|||
package resolver
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"net"
|
||||
|
||||
cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
|
||||
)
|
||||
|
||||
const (
|
||||
testnetDomain = ".containers.testnet.fs.neo.org"
|
||||
mainnetDomain = ".containers.fs.neo.org"
|
||||
)
|
||||
// DNS looks up NeoFS names using system DNS.
|
||||
//
|
||||
// See also net package.
|
||||
type DNS struct{}
|
||||
|
||||
// ResolveContainerTestnet request txt record name + '.containers.testnet.fs.neo.org' to default dns server.
|
||||
func ResolveContainerTestnet(name string) (*cid.ID, error) {
|
||||
return ResolveContainerDomainName(name + testnetDomain)
|
||||
}
|
||||
|
||||
// ResolveContainerMainnet request txt record name + '.containers.fs.neo.org' to default dns server.
|
||||
func ResolveContainerMainnet(name string) (*cid.ID, error) {
|
||||
return ResolveContainerDomainName(name + mainnetDomain)
|
||||
}
|
||||
|
||||
// ResolveContainerDomainName trys to resolve container domain name to container ID using system dns server.
|
||||
func ResolveContainerDomainName(domain string) (*cid.ID, error) {
|
||||
results, err := net.LookupTXT(domain)
|
||||
// ResolveContainerName looks up for DNS TXT records for the given domain name
|
||||
// and returns the first one which represents valid container ID in a string format.
|
||||
// Otherwise, returns an error.
|
||||
//
|
||||
// See also net.LookupTXT.
|
||||
func (x *DNS) ResolveContainerName(name string) (*cid.ID, error) {
|
||||
records, err := net.LookupTXT(name)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
cnrID := cid.New()
|
||||
for _, res := range results {
|
||||
if err = cnrID.Parse(res); err != nil {
|
||||
continue
|
||||
var id cid.ID
|
||||
|
||||
for i := range records {
|
||||
err = id.Parse(records[i])
|
||||
if err == nil {
|
||||
return &id, nil
|
||||
}
|
||||
return cnrID, nil
|
||||
}
|
||||
|
||||
return nil, fmt.Errorf("not found")
|
||||
return nil, errNotFound
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,22 @@
|
|||
/*
|
||||
Package resolver provides functionality of NeoFS name system.
|
||||
|
||||
DNS type is designed to resolve NeoFS-related names using Domain Name System:
|
||||
const containerName = "some-container"
|
||||
|
||||
var dns DNS
|
||||
|
||||
containerID, err := dns.ResolveContainerName(containerName)
|
||||
// ...
|
||||
|
||||
NNS type is designed to resolve NeoFS-related names using Neo Name Service:
|
||||
var nns NNS
|
||||
|
||||
err := nns.Dial(nnsServerAddress)
|
||||
// ...
|
||||
|
||||
containerID, err := nns.ResolveContainerName(containerName)
|
||||
// ...
|
||||
|
||||
*/
|
||||
package resolver
|
||||
152
resolver/nns.go
152
resolver/nns.go
|
|
@ -1,10 +1,12 @@
|
|||
package resolver
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
"fmt"
|
||||
|
||||
nns "github.com/nspcc-dev/neo-go/examples/nft-nd-nns"
|
||||
"github.com/nspcc-dev/neo-go/pkg/rpc/client"
|
||||
neoclient "github.com/nspcc-dev/neo-go/pkg/rpc/client"
|
||||
"github.com/nspcc-dev/neo-go/pkg/rpc/response/result"
|
||||
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
|
||||
"github.com/nspcc-dev/neo-go/pkg/util"
|
||||
|
|
@ -13,109 +15,103 @@ import (
|
|||
cid "github.com/nspcc-dev/neofs-sdk-go/container/id"
|
||||
)
|
||||
|
||||
type NNSResolver interface {
|
||||
// ResolveContainerName get record for domain name+'.container' from NNS contract.
|
||||
ResolveContainerName(name string) (*cid.ID, error)
|
||||
// NNS looks up NeoFS 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
|
||||
|
||||
// neoclient.Client interface wrapper, needed for testing
|
||||
neoClient interface {
|
||||
invoke(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error)
|
||||
}
|
||||
}
|
||||
|
||||
type nnsResolver struct {
|
||||
rpc *client.Client
|
||||
nnsHash util.Uint160
|
||||
// client is a core implementation of internal NNS.neoClient which is used by NNS.Dial.
|
||||
type client neoclient.Client
|
||||
|
||||
func (x *client) invoke(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error) {
|
||||
return (*neoclient.Client)(x).InvokeFunction(contract, method, prm, nil)
|
||||
}
|
||||
|
||||
const (
|
||||
resolve = "resolve"
|
||||
containerDomain = ".container"
|
||||
)
|
||||
|
||||
// NewNNSResolver creates resolver that can get records from NNS contract.
|
||||
func NewNNSResolver(rpc *client.Client) (NNSResolver, error) {
|
||||
nnsContract, err := rpc.GetContractStateByID(1)
|
||||
// Dial connects to the address of the NNS server. If fails, the instance
|
||||
// SHOULD NOT be used.
|
||||
func (n *NNS) Dial(address string) error {
|
||||
cli, err := neoclient.New(context.Background(), address, neoclient.Options{})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
return fmt.Errorf("create neo client: %w", err)
|
||||
}
|
||||
|
||||
return &nnsResolver{
|
||||
rpc: rpc,
|
||||
nnsHash: nnsContract.Hash,
|
||||
}, nil
|
||||
if err = cli.Init(); err != nil {
|
||||
return fmt.Errorf("initialize neo client: %w", err)
|
||||
}
|
||||
|
||||
nnsContract, err := cli.GetContractStateByID(1)
|
||||
if err != nil {
|
||||
return fmt.Errorf("get NNS contract state: %w", err)
|
||||
}
|
||||
|
||||
n.neoClient = (*client)(cli)
|
||||
n.nnsContract = nnsContract.Hash
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func (n *nnsResolver) ResolveContainerName(name string) (*cid.ID, error) {
|
||||
res, err := n.rpc.InvokeFunction(n.nnsHash, resolve, []smartcontract.Parameter{
|
||||
// ResolveContainerName looks up for NNS TXT records for the given container name
|
||||
// by calling `resolve` method of NNS contract. Returns the first record which represents
|
||||
// valid container ID in a string format. Otherwise, returns an error.
|
||||
//
|
||||
// ResolveContainerName MUST NOT be called before successful Dial.
|
||||
//
|
||||
// See also https://docs.neo.org/docs/en-us/reference/nns.html.
|
||||
func (n *NNS) ResolveContainerName(name string) (*cid.ID, error) {
|
||||
res, err := n.neoClient.invoke(n.nnsContract, "resolve", []smartcontract.Parameter{
|
||||
{
|
||||
Type: smartcontract.StringType,
|
||||
Value: name + containerDomain,
|
||||
Value: name + ".container",
|
||||
},
|
||||
{
|
||||
Type: smartcontract.IntegerType,
|
||||
Value: int64(nns.TXT),
|
||||
},
|
||||
}, nil)
|
||||
})
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if err = getInvocationError(res); err != nil {
|
||||
return nil, err
|
||||
return nil, fmt.Errorf("invoke NNS contract: %w", err)
|
||||
}
|
||||
|
||||
arr, err := getArrString(res.Stack)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
if res.State != vm.HaltState.String() {
|
||||
return nil, fmt.Errorf("NNS contract fault exception: %s", res.FaultException)
|
||||
} else if len(res.Stack) == 0 {
|
||||
return nil, errors.New("empty stack in invocation result")
|
||||
}
|
||||
|
||||
cnrID := cid.New()
|
||||
for _, rec := range arr {
|
||||
if err = cnrID.Parse(rec); err != nil {
|
||||
continue
|
||||
itemArr, err := res.Stack[len(res.Stack)-1].Convert(stackitem.ArrayT) // top stack element is last in the array
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("convert stack item to %s", stackitem.ArrayT)
|
||||
}
|
||||
|
||||
if _, ok := itemArr.(stackitem.Null); !ok {
|
||||
arr, ok := itemArr.Value().([]stackitem.Item)
|
||||
if !ok {
|
||||
// unexpected for types from stackitem package
|
||||
return nil, errors.New("invalid cast to stack item slice")
|
||||
}
|
||||
return cnrID, nil
|
||||
}
|
||||
|
||||
return nil, fmt.Errorf("not found")
|
||||
}
|
||||
var id cid.ID
|
||||
|
||||
func getArrString(st []stackitem.Item) ([]string, error) {
|
||||
array, err := getArray(st)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
for i := range arr {
|
||||
bs, err := arr[i].TryBytes()
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("convert array item to byte slice: %w", err)
|
||||
}
|
||||
|
||||
res := make([]string, len(array))
|
||||
for i, item := range array {
|
||||
bs, err := item.TryBytes()
|
||||
if err != nil {
|
||||
return nil, err
|
||||
err = id.Parse(string(bs))
|
||||
if err == nil {
|
||||
return &id, nil
|
||||
}
|
||||
}
|
||||
res[i] = string(bs)
|
||||
}
|
||||
|
||||
return res, nil
|
||||
}
|
||||
|
||||
func getArray(st []stackitem.Item) ([]stackitem.Item, error) {
|
||||
index := len(st) - 1 // top stack element is last in the array
|
||||
arr, err := st[index].Convert(stackitem.ArrayT)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
if _, ok := arr.(stackitem.Null); ok {
|
||||
return nil, nil
|
||||
}
|
||||
|
||||
iterator, ok := arr.Value().([]stackitem.Item)
|
||||
if !ok {
|
||||
return nil, fmt.Errorf("bad conversion")
|
||||
}
|
||||
return iterator, nil
|
||||
}
|
||||
|
||||
func getInvocationError(result *result.Invoke) error {
|
||||
if result.State != vm.HaltState.String() {
|
||||
return fmt.Errorf("invocation failed: %s", result.FaultException)
|
||||
}
|
||||
if len(result.Stack) == 0 {
|
||||
return fmt.Errorf("result stack is empty")
|
||||
}
|
||||
return nil
|
||||
return nil, errNotFound
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,157 @@
|
|||
package resolver
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"fmt"
|
||||
"math/big"
|
||||
"math/rand"
|
||||
"strings"
|
||||
"testing"
|
||||
|
||||
nns "github.com/nspcc-dev/neo-go/examples/nft-nd-nns"
|
||||
"github.com/nspcc-dev/neo-go/pkg/rpc/response/result"
|
||||
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
|
||||
"github.com/nspcc-dev/neo-go/pkg/util"
|
||||
"github.com/nspcc-dev/neo-go/pkg/vm"
|
||||
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
|
||||
cidtest "github.com/nspcc-dev/neofs-sdk-go/container/id/test"
|
||||
"github.com/stretchr/testify/require"
|
||||
)
|
||||
|
||||
// testNeoClient represents test Neo client which checks invocation arguments
|
||||
// and returns predefined result.
|
||||
type testNeoClient struct {
|
||||
t *testing.T
|
||||
|
||||
expectedContract util.Uint160
|
||||
|
||||
res result.Invoke
|
||||
|
||||
err error
|
||||
}
|
||||
|
||||
func (x *testNeoClient) invoke(contract util.Uint160, method string, prm []smartcontract.Parameter) (*result.Invoke, error) {
|
||||
require.Equal(x.t, x.expectedContract, contract)
|
||||
require.Equal(x.t, "resolve", method)
|
||||
require.Len(x.t, prm, 2)
|
||||
require.Equal(x.t, smartcontract.StringType, prm[0].Type)
|
||||
require.Equal(x.t, smartcontract.IntegerType, prm[1].Type)
|
||||
require.EqualValues(x.t, nns.TXT, prm[1].Value)
|
||||
|
||||
val, ok := prm[0].Value.(string)
|
||||
require.True(x.t, ok)
|
||||
require.True(x.t, strings.HasSuffix(val, ".container"))
|
||||
require.NotEmpty(x.t, strings.TrimSuffix(val, ".container"))
|
||||
|
||||
return &x.res, x.err
|
||||
}
|
||||
|
||||
// implements test stackitem.Item which is obviously incorrect:
|
||||
// it returns itself on Convert(stackitem.ArrayT), but returns integer from Value.
|
||||
type brokenArrayStackItem struct {
|
||||
stackitem.Item
|
||||
}
|
||||
|
||||
func (x brokenArrayStackItem) Value() interface{} {
|
||||
return 1
|
||||
}
|
||||
|
||||
func (x brokenArrayStackItem) Convert(t stackitem.Type) (stackitem.Item, error) {
|
||||
if t != stackitem.ArrayT {
|
||||
panic(fmt.Sprintf("unexpected stack item type %s", t))
|
||||
}
|
||||
|
||||
return x, nil
|
||||
}
|
||||
|
||||
func TestNNS_ResolveContainerName(t *testing.T) {
|
||||
const testContainerName = "some_container"
|
||||
|
||||
var nnsContract util.Uint160
|
||||
|
||||
rand.Read(nnsContract[:])
|
||||
|
||||
testC := &testNeoClient{
|
||||
t: t,
|
||||
expectedContract: nnsContract,
|
||||
}
|
||||
|
||||
n := NNS{
|
||||
nnsContract: nnsContract,
|
||||
neoClient: testC,
|
||||
}
|
||||
|
||||
t.Run("invocation failure", func(t *testing.T) {
|
||||
testC.err = errors.New("invoke err")
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
testC.err = nil
|
||||
|
||||
t.Run("fault exception", func(t *testing.T) {
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
testC.res.State = vm.HaltState.String()
|
||||
|
||||
t.Run("empty stack", func(t *testing.T) {
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
testC.res.Stack = make([]stackitem.Item, 1)
|
||||
|
||||
t.Run("non-array last stack item", func(t *testing.T) {
|
||||
testC.res.Stack[0] = stackitem.NewBigInteger(big.NewInt(11))
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
t.Run("null array", func(t *testing.T) {
|
||||
testC.res.Stack[0] = stackitem.Null{}
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
t.Run("array stack item with non-slice value", func(t *testing.T) {
|
||||
testC.res.Stack[0] = brokenArrayStackItem{}
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
arr := make([]stackitem.Item, 2)
|
||||
testC.res.Stack[0] = stackitem.NewArray(arr)
|
||||
|
||||
t.Run("non-bytes array element", func(t *testing.T) {
|
||||
arr[0] = stackitem.NewArray(nil)
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
arr[0] = stackitem.NewByteArray([]byte("some byte array 1"))
|
||||
|
||||
t.Run("non-container array elements", func(t *testing.T) {
|
||||
arr[1] = stackitem.NewByteArray([]byte("some byte array 2"))
|
||||
|
||||
_, err := n.ResolveContainerName(testContainerName)
|
||||
require.Error(t, err)
|
||||
})
|
||||
|
||||
t.Run("with container array element", func(t *testing.T) {
|
||||
id := cidtest.ID()
|
||||
|
||||
arr[1] = stackitem.NewByteArray([]byte(id.String()))
|
||||
|
||||
res, err := n.ResolveContainerName(testContainerName)
|
||||
require.NoError(t, err)
|
||||
|
||||
require.Equal(t, id, res)
|
||||
})
|
||||
}
|
||||
|
|
@ -0,0 +1,5 @@
|
|||
package resolver
|
||||
|
||||
import "errors"
|
||||
|
||||
var errNotFound = errors.New("record not found")
|
||||
Loading…
Reference in New Issue