Implement Bitcore socket.io method estimateSmartFee

bchain/bitcoinrpc.go

@@ -132,6 +132,24 @@ type resGetRawTransactionVerbose struct {
 	Result Tx        `json:"result"`
 }
 
+// estimatesmartfee
+
+type cmdEstimateSmartFee struct {
+	Method string `json:"method"`
+	Params struct {
+		ConfTarget   int    `json:"conf_target"`
+		EstimateMode string `json:"estimate_mode"`
+	} `json:"params"`
+}
+
+type resEstimateSmartFee struct {
+	Error  *RPCError `json:"error"`
+	Result struct {
+		Feerate float64 `json:"feerate"`
+		Blocks  int     `json:"blocks"`
+	} `json:"result"`
+}
+
 type BlockParser interface {
 	ParseBlock(b []byte) (*Block, error)
 }
@@ -355,6 +373,29 @@ func (b *BitcoinRPC) GetTransaction(txid string) (*Tx, error) {
 	return &res.Result, nil
 }
 
+// EstimateSmartFee returns fee estimation.
+func (b *BitcoinRPC) EstimateSmartFee(blocks int, conservative bool) (float64, error) {
+	glog.V(1).Info("rpc: estimatesmartfee ", blocks)
+
+	res := resEstimateSmartFee{}
+	req := cmdEstimateSmartFee{Method: "estimatesmartfee"}
+	req.Params.ConfTarget = blocks
+	if conservative {
+		req.Params.EstimateMode = "CONSERVATIVE"
+	} else {
+		req.Params.EstimateMode = "ECONOMICAL"
+	}
+	err := b.call(&req, &res)
+
+	if err != nil {
+		return 0, err
+	}
+	if res.Error != nil {
+		return 0, res.Error
+	}
+	return res.Result.Feerate, nil
+}
+
 func (b *BitcoinRPC) call(req interface{}, res interface{}) error {
 	httpData, err := json.Marshal(req)
 	if err != nil {

server/socketio.go

@@ -103,21 +103,38 @@ type reqRange struct {
 	To               int  `json:"to"`
 }
 
+var onMessageHandlers = map[string]func(*SocketIoServer, json.RawMessage) (interface{}, error){
+	"\"getAddressTxids\"": func(s *SocketIoServer, params json.RawMessage) (rv interface{}, err error) {
+		addr, rr, err := unmarshalGetAddressTxids(params)
+		if err == nil {
+			rv, err = s.getAddressTxids(addr, &rr)
+		}
+		return
+	},
+	"\"getBlockHeader\"": func(s *SocketIoServer, params json.RawMessage) (rv interface{}, err error) {
+		height, hash, err := unmarshalGetBlockHeader(params)
+		if err == nil {
+			rv, err = s.getBlockHeader(height, hash)
+		}
+		return
+	},
+	"\"estimateSmartFee\"": func(s *SocketIoServer, params json.RawMessage) (rv interface{}, err error) {
+		blocks, conservative, err := unmarshalEstimateSmartFee(params)
+		if err == nil {
+			rv, err = s.estimateSmartFee(blocks, conservative)
+		}
+		return
+	},
+}
+
 func (s *SocketIoServer) onMessage(c *gosocketio.Channel, req map[string]json.RawMessage) interface{} {
 	var err error
 	var rv interface{}
 	method := string(req["method"])
 	params := req["params"]
-	if method == "\"getAddressTxids\"" {
+	f, ok := onMessageHandlers[method]
-		addr, rr, err := unmarshalGetAddressTxids(params)
+	if ok {
-		if err == nil {
+		rv, err = f(s, params)
-			rv, err = s.getAddressTxids(addr, &rr)
-		}
-	} else if method == "\"getBlockHeader\"" {
-		height, hash, err := unmarshalGetBlockHeader(params)
-		if err == nil {
-			rv, err = s.getBlockHeader(height, hash)
-		}
 	} else {
 		err = errors.New("unknown method")
 	}
@@ -184,16 +201,23 @@ func (s *SocketIoServer) getAddressTxids(addr []string, rr *reqRange) ([]string,
 	return txids, nil
 }
 
-func unmarshalGetBlockHeader(params []byte) (height uint32, hash string, err error) {
+func unmarshalArray(params []byte, np int) (p []interface{}, err error) {
-	var p []interface{}
 	err = json.Unmarshal(params, &p)
 	if err != nil {
 		return
 	}
-	if len(p) != 1 {
+	if len(p) != np {
 		err = errors.New("incorrect number of parameters")
 		return
 	}
+	return
+}
+
+func unmarshalGetBlockHeader(params []byte) (height uint32, hash string, err error) {
+	p, err := unmarshalArray(params, 1)
+	if err != nil {
+		return
+	}
 	fheight, ok := p[0].(float64)
 	if ok {
 		return uint32(fheight), "", nil
@@ -248,6 +272,38 @@ func (s *SocketIoServer) getBlockHeader(height uint32, hash string) (res resultG
 	return
 }
 
+func unmarshalEstimateSmartFee(params []byte) (blocks int, conservative bool, err error) {
+	p, err := unmarshalArray(params, 2)
+	if err != nil {
+		return
+	}
+	fblocks, ok := p[0].(float64)
+	if !ok {
+		err = errors.New("Invalid parameter blocks")
+		return
+	}
+	blocks = int(fblocks)
+	conservative, ok = p[1].(bool)
+	if !ok {
+		err = errors.New("Invalid parameter conservative")
+		return
+	}
+	return
+}
+
+type resultEstimateSmartFee struct {
+	Result float64 `json:"result"`
+}
+
+func (s *SocketIoServer) estimateSmartFee(blocks int, conservative bool) (res resultEstimateSmartFee, err error) {
+	fee, err := s.chain.EstimateSmartFee(blocks, conservative)
+	if err != nil {
+		return
+	}
+	res.Result = fee
+	return
+}
+
 func (s *SocketIoServer) onSubscribe(c *gosocketio.Channel, req map[string]json.RawMessage) interface{} {
 	glog.Info(c.Id(), " onSubscribe ", req)
 	return nil

server/static/test.html

@@ -66,6 +66,21 @@
             return socket.send({ method, params }, f);
         }
 
+        function estimateSmartFee() {
+            var blocks = document.getElementById('estimateSmartFeeBlocks').value;
+            var conservative = document.getElementById("estimateSmartFeeConservative").checked;
+            estimateSmartTxFee(parseInt(blocks), conservative, function (result) {
+                console.log('estimateSmartFee sent successfully');
+                console.log(result);
+                document.getElementById('estimateSmartFeeResult').innerText = JSON.stringify(result).replace(/,/g, ", ");
+            });
+        }
+
+        function estimateSmartTxFee(blocks, conservative, f) {
+            const method = 'estimateSmartFee';
+            const params = [blocks, conservative];
+            return socket.send({ method, params }, f);
+        }
     </script>
 </head>
 
@@ -115,6 +130,22 @@
             <div class="col" id="getBlockHeaderResult">
             </div>
         </div>
+        <div class="row">
+            <div class="col">
+                <input class="btn btn-secondary" type="button" value="estimateSmartFee" onclick="estimateSmartFee()">
+            </div>
+            <div class="col-8">
+                <input type="text" class="form-control" id="estimateSmartFeeBlocks" value="20">
+            </div>
+            <div class="col form-inline">
+                <input type="checkbox" id="estimateSmartFeeConservative" checked>&nbsp;
+                <label>conservative</label>
+            </div>
+        </div>
+        <div class="row">
+            <div class="col" id="estimateSmartFeeResult">
+            </div>
+        </div>
     </div>
     </div>
 </body>