Merge pull request #37 from libsv/enhancement/feeQuote_marshall

Marshal/ Unmarshal feeQuote

fees.go

@@ -1,7 +1,9 @@
 package bt
 
 import (
+	"encoding/json"
 	"errors"
+	"fmt"
 	"sync"
 	"time"
 )
@@ -13,6 +15,7 @@ var (
 	ErrFeeTypeNotFound  = errors.New("feetype not found")
 	ErrFeeQuoteNotInit  = errors.New("feeQuote has not been initialised, call NewFeeQuote()")
 	ErrEmptyValues      = errors.New("empty value or values passed, all arguments are required and cannot be empty")
+	ErrUnknownFeeType   = "unknown feetype supplied '%s'"
 )
 
 // FeeType is used to specify which
@@ -225,6 +228,52 @@ func (f *FeeQuote) Expired() bool {
 	return f.expiryTime.Before(time.Now().UTC())
 }
 
+// MarshalJSON will convert the FeeQuote to a json object
+// with the format as shown:
+//  {
+//	 "data": {
+//		 "miningFee": {
+//			 "satoshis": 5,
+//			 "bytes": 2
+//		 },
+//		 "relayFee": {
+//			 "satoshis": 8,
+//			 "bytes": 4
+//		 }
+//	 },
+//	 "standard": {
+//		 "miningFee": {
+//			 "satoshis": 100,
+//			 "bytes": 10
+//		 },
+//		 "relayFee": {
+//			 "satoshis": 10,
+//			 "bytes": 5
+//		 }
+//	 }
+//  }
+func (f *FeeQuote) MarshalJSON() ([]byte, error) {
+	return json.Marshal(f.fees)
+}
+
+// UnmarshalJSON will convert a json encoded FeeQuote back into a fee quote type, the expected
+// JSON format is shown above in the MarshalJSON function.
+// If the fee type supplied is unknown an ErrUnknownFeeType will be returned.
+func (f *FeeQuote) UnmarshalJSON(body []byte) error {
+	fees := map[FeeType]*Fee{}
+	if err := json.Unmarshal(body, &fees); err != nil {
+		return err
+	}
+	for k, v := range fees {
+		if k != FeeTypeData && k != FeeTypeStandard {
+			return fmt.Errorf(ErrUnknownFeeType, k)
+		}
+		v.FeeType = k
+	}
+	f.fees = fees
+	return nil
+}
+
 // FeeUnit displays the amount of Satoshis needed
 // for a specific amount of Bytes in a transaction
 // see https://github.com/bitcoin-sv-specs/brfc-misc/tree/master/feespec
@@ -237,7 +286,7 @@ type FeeUnit struct {
 // FeeType, for example 'standard' or 'data'
 // see https://github.com/bitcoin-sv-specs/brfc-misc/tree/master/feespec
 type Fee struct {
-	FeeType   FeeType `json:"feeType"` // standard || data
+	FeeType   FeeType `json:"-"` // standard || data
 	MiningFee FeeUnit `json:"miningFee"`
 	RelayFee  FeeUnit `json:"relayFee"` // Fee for retaining Tx in secondary mempool
 }

fees_test.go

@@ -1,6 +1,8 @@
 package bt
 
 import (
+	"encoding/json"
+	"errors"
 	"sync"
 	"testing"
 	"time"
@@ -539,3 +541,84 @@ func TestFeeQuotes_Fee(t *testing.T) {
 		})
 	}
 }
+
+func TestFeeQuote_MarshalUnmarshalJSON(t *testing.T) {
+	t.Parallel()
+	tests := map[string]struct {
+		quote *FeeQuote
+		err   error
+	}{
+		"successful run should return no errors": {
+			quote: &FeeQuote{
+				fees: map[FeeType]*Fee{
+					FeeTypeStandard: {
+						FeeType: FeeTypeStandard,
+						MiningFee: FeeUnit{
+							Satoshis: 100,
+							Bytes:    10,
+						},
+						RelayFee: FeeUnit{
+							Satoshis: 10,
+							Bytes:    5},
+					}, FeeTypeData: {
+						FeeType: FeeTypeData,
+						MiningFee: FeeUnit{
+							Satoshis: 5,
+							Bytes:    2,
+						},
+						RelayFee: FeeUnit{
+							Satoshis: 8,
+							Bytes:    4},
+					},
+				},
+			},
+			err: nil,
+		},
+		"empty key should error": {
+			quote: &FeeQuote{
+				fees: map[FeeType]*Fee{
+					"": {
+						FeeType: FeeTypeStandard,
+						MiningFee: FeeUnit{
+							Satoshis: 100,
+							Bytes:    10,
+						},
+						RelayFee: FeeUnit{
+							Satoshis: 10,
+							Bytes:    5},
+					},
+				},
+			},
+			err: errors.New("unknown feetype supplied ''"),
+		}, "random key should error": {
+			quote: &FeeQuote{
+				fees: map[FeeType]*Fee{
+					"idunno": {
+						FeeType: FeeTypeStandard,
+						MiningFee: FeeUnit{
+							Satoshis: 100,
+							Bytes:    10,
+						},
+						RelayFee: FeeUnit{
+							Satoshis: 10,
+							Bytes:    5},
+					},
+				},
+			},
+			err: errors.New("unknown feetype supplied 'idunno'"),
+		},
+	}
+	for name, test := range tests {
+		t.Run(name, func(t *testing.T) {
+			bb, _ := json.Marshal(test.quote)
+			var quote *FeeQuote
+			err := json.Unmarshal(bb, &quote)
+			if test.err != nil {
+				assert.Error(t, err)
+				assert.EqualError(t, err, test.err.Error())
+				return
+			}
+			assert.Equal(t, test.quote, quote)
+		})
+	}
+}