[#421] morph/client: Add role getter from designate contract

RoleManagement native contract (ex designate contract) stores list
of keys per role. Main net uses NeoFSAlphabet role to store keys of
alphabet nodes of inner ring. Side chain uses the same role to store
keys of all inner ring nodes, including alphabet.

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

pkg/morph/client/client.go

@@ -37,6 +37,8 @@ type Client struct {
 
 	neo util.Uint160 // native neo script-hash
 
+	designate util.Uint160 // native designate script-hash
+
 	waitInterval time.Duration
 
 	notary *notary
@@ -51,6 +53,7 @@ const HaltState = "HALT"
 
 const (
 	committeeList = "getCommittee"
+	designateList = "getDesignatedByRole"
 )
 
 var errEmptyInvocationScript = errors.New("got empty invocation script from neo node")
@@ -214,6 +217,25 @@ func (c *Client) Committee() (keys.PublicKeys, error) {
 	return roleKeys, nil
 }
 
+func (c *Client) roleList(r native.Role) (keys.PublicKeys, error) {
+	height, err := c.client.GetBlockCount()
+	if err != nil {
+		return nil, errors.Wrap(err, "can't get chain height")
+	}
+
+	items, err := c.TestInvoke(c.designate, designateList, r, int64(height))
+	if err != nil {
+		return nil, err
+	}
+
+	roleKeys, err := keysFromStack(items)
+	if err != nil {
+		return nil, errors.Wrap(err, "can't get role keys")
+	}
+
+	return roleKeys, nil
+}
+
 func toStackParameter(value interface{}) (sc.Parameter, error) {
 	var result = sc.Parameter{
 		Value: value,

pkg/morph/client/constructor.go

@@ -105,12 +105,18 @@ func New(key *ecdsa.PrivateKey, endpoint string, opts ...Option) (*Client, error
 		return nil, err
 	}
 
+	designate, err := cli.GetNativeContractHash(nativenames.Designation)
+	if err != nil {
+		return nil, err
+	}
+
 	return &Client{
 		logger:       cfg.logger,
 		client:       cli,
 		acc:          account,
 		gas:          gas,
 		neo:          neo,
+		designate:    designate,
 		waitInterval: cfg.waitInterval,
 	}, nil
 }