Refactoring

* refactor http transport call method, use mutex in requestID generation
* replace pkg/errors with errors and fmt package
* make CreateSignedTransaction public

Author: Alexander Plevako

client.go

@@ -64,15 +64,15 @@ func (client *Client) Close() error {
 }
 
 func (client *Client) BroadcastTransactionSynchronous(ctx context.Context, chainID []byte, operations []types.Operation, keys ...*key.PrivateKey) (*network_broadcast.BroadcastResponse, error) {
-	stx, err := client.createSignedTransaction(ctx, chainID, operations, keys...)
+	stx, err := client.CreateSignedTransaction(ctx, chainID, operations, keys...)
 	if err != nil {
 		return nil, err
 	}
 	return client.NetworkBroadcast.BroadcastTransactionSynchronous(ctx, stx.Transaction)
 }
 
 func (client *Client) BroadcastTransaction(ctx context.Context, chainID []byte, operations []types.Operation, keys ...*key.PrivateKey) (string, error) {
-	stx, err := client.createSignedTransaction(ctx, chainID, operations, keys...)
+	stx, err := client.CreateSignedTransaction(ctx, chainID, operations, keys...)
 	if err != nil {
 		return "", err
 	}
@@ -82,7 +82,7 @@ func (client *Client) BroadcastTransaction(ctx context.Context, chainID []byte,
 	return hex.EncodeToString(id), client.NetworkBroadcast.BroadcastTransaction(ctx, stx.Transaction)
 }
 
-func (client *Client) createSignedTransaction(ctx context.Context, chainID []byte, operations []types.Operation, keys ...*key.PrivateKey) (*sign.SignedTransaction, error) {
+func (client *Client) CreateSignedTransaction(ctx context.Context, chainID []byte, operations []types.Operation, keys ...*key.PrivateKey) (*sign.SignedTransaction, error) {
 	props, err := client.Chain.GetChainProperties(ctx)
 	if err != nil {
 		return nil, fmt.Errorf("get chainID properties: %w", err)

sign/transactions.go

@@ -4,8 +4,8 @@ import (
 	"bytes"
 	"encoding/binary"
 	"encoding/hex"
-
-	"github.com/pkg/errors"
+	"errors"
+	"fmt"
 )
 
 func RefBlockNum(blockNumber uint32) uint16 {
@@ -16,20 +16,20 @@ func RefBlockPrefix(blockID string) (uint32, error) {
 	// Block ID is hex-encoded.
 	rawBlockID, err := hex.DecodeString(blockID)
 	if err != nil {
-		return 0, errors.Wrapf(err, "network_broadcast: failed to decode block ID: %v", blockID)
+		return 0, fmt.Errorf("failed to decode block ID: %w", err)
 	}
 
 	// Raw prefix = raw block ID [4:8].
 	// Make sure we don't trigger a slice bounds out of range panic.
 	if len(rawBlockID) < 8 {
-		return 0, errors.Errorf("network_broadcast: invalid block ID: %v", blockID)
+		return 0, errors.New("invalid blockID")
 	}
 	rawPrefix := rawBlockID[4:8]
 
 	// Decode the prefix.
 	var prefix uint32
 	if err := binary.Read(bytes.NewReader(rawPrefix), binary.LittleEndian, &prefix); err != nil {
-		return 0, errors.Wrapf(err, "network_broadcast: failed to read block prefix: %v", rawPrefix)
+		return 0, fmt.Errorf("failed to read block prefix: %w", err)
 	}
 
 	// Done, return the prefix.

transport/generator.go

@@ -0,0 +1,24 @@
+package transport
+
+import "sync"
+
+type SequenceGenerator struct {
+	requestID uint64
+	mtx       sync.Mutex
+}
+
+func NewSequenceGenerator(initial uint64) *SequenceGenerator {
+	return &SequenceGenerator{
+		requestID: initial,
+		mtx:       sync.Mutex{},
+	}
+}
+
+func (r *SequenceGenerator) Generate() uint64 {
+	r.mtx.Lock()
+	defer r.mtx.Unlock()
+
+	r.requestID++
+
+	return r.requestID
+}

transport/http/transport.go

@@ -5,27 +5,29 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
+	"io"
 	"io/ioutil"
-	"math"
 	"net/http"
-	"sync"
 	"time"
 
-	"github.com/pkg/errors"
 	"github.com/scorum/scorum-go/transport"
 )
 
+type requestIDGenerator interface {
+	Generate() uint64
+}
+
 type Transport struct {
 	Url    string
 	client *http.Client
 
-	requestID uint64
-	reqMutex  sync.Mutex
+	requestID requestIDGenerator
 }
 
 func NewTransport(url string, options ...func(*Transport)) *Transport {
 	t := Transport{
-		Url: url,
+		Url:       url,
+		requestID: transport.NewSequenceGenerator(0),
 	}
 
 	for _, o := range options {
@@ -48,59 +50,45 @@ func WithHttpClient(client *http.Client) func(*Transport) {
 }
 
 func (caller *Transport) Call(ctx context.Context, api string, method string, args []interface{}, reply interface{}) error {
-	caller.reqMutex.Lock()
-	defer caller.reqMutex.Unlock()
-
-	// increase request id
-	if caller.requestID == math.MaxUint64 {
-		caller.requestID = 0
-	}
-	caller.requestID++
-
 	request := transport.RPCRequest{
 		Method: "call",
-		ID:     caller.requestID,
+		ID:     caller.requestID.Generate(),
 		Params: []interface{}{api, method, args},
 	}
 
 	reqBody, err := json.Marshal(request)
 	if err != nil {
-		return err
+		return fmt.Errorf("json marshall: %w", err)
 	}
 
 	req, err := http.NewRequestWithContext(ctx, "POST", caller.Url, bytes.NewBuffer(reqBody))
 	if err != nil {
-		return err
+		return fmt.Errorf("http new request: %w", err)
 	}
 	req.Header.Set("Content-Type", "application/json")
 
 	resp, err := caller.client.Do(req)
 	if err != nil {
-		return err
+		return fmt.Errorf("http client do: %w", err)
 	}
 	defer resp.Body.Close()
 
 	if resp.StatusCode != http.StatusOK {
 		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
 	}
 
-	respBody, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return errors.Wrap(err, "failed to read body")
-	}
-
 	var rpcResponse transport.RPCResponse
-	if err = json.Unmarshal(respBody, &rpcResponse); err != nil {
-		return errors.Wrapf(err, "failed to unmarshal response: %+v", string(respBody))
+	if err := decodeJSON(resp.Body, &rpcResponse); err != nil {
+		return fmt.Errorf("failed decode rpc response: %w", err)
 	}
 
 	if rpcResponse.Error != nil {
 		return rpcResponse.Error
 	}
 
 	if rpcResponse.Result != nil {
-		if err := json.Unmarshal(*rpcResponse.Result, reply); err != nil {
-			return errors.Wrapf(err, "failed to unmarshal rpc result: %+v", string(*rpcResponse.Result))
+		if err := decodeJSON(bytes.NewReader(*rpcResponse.Result), reply); err != nil {
+			return fmt.Errorf("failed decode rpc result: %w", err)
 		}
 	}
 
@@ -114,3 +102,21 @@ func (caller *Transport) SetCallback(api string, method string, notice func(args
 func (caller *Transport) Close() error {
 	return nil
 }
+
+func decodeJSON(reader io.Reader, out interface{}) error {
+	buf := new(bytes.Buffer)
+	tr := io.TeeReader(reader, buf)
+
+	data, err := ioutil.ReadAll(tr)
+	if err != nil {
+		return fmt.Errorf("failed to read body: %w", err)
+	}
+	if !json.Valid(data) {
+		return fmt.Errorf("invalid json: %q", buf.String())
+	}
+
+	if err := json.NewDecoder(buf).Decode(out); err != nil {
+		return fmt.Errorf("failed to decode json: %w", err)
+	}
+	return nil
+}

types/game.go

@@ -2,7 +2,7 @@ package types
 
 import (
 	"encoding/json"
-	"github.com/pkg/errors"
+	"errors"
 	"reflect"
 )