txnbuild: add support for ManageBuyOffer

txnbuild/CHANGELOG.md

@@ -8,6 +8,7 @@ file.  This project adheres to [Semantic Versioning](http://semver.org/).
 * In addition to account responses from horizon, transactions and operations can now be built with txnbuild.SimpleAccount structs constructed locally. 
 * Added `MaxTrustlineLimit` which represents the maximum value for a trustline limit.
 * ChangeTrust operation with no `Limit` field set now defaults to `MaxTrustlineLimit`.
+* Add support for building `ManageBuyOffer` operation.
 
 ## [v1.1.0](https://github.com/stellar/go/releases/tag/horizonclient-v1.1.0) - 2019-02-02
 

txnbuild/example_test.go

@@ -434,3 +434,33 @@ func ExamplePathPayment() {
 
 	// Output: AAAAAH4RyzTWNfXhqwLUoCw91aWkZtgIzY8SAVkIPc0uFVmYAAAAZAAMoj8AAAAEAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAACAAAAAAAAAAAF9eEAAAAAAH4RyzTWNfXhqwLUoCw91aWkZtgIzY8SAVkIPc0uFVmYAAAAAAAAAAAAmJaAAAAAAQAAAAFBQkNEAAAAAODcbeFyXKxmUWK1L6znNbKKIkPkHRJNbLktcKPqLnLFAAAAAAAAAAEuFVmYAAAAQOGE+w2bvIp8JQIPIFXWk5kO77cNUOlPZwlItA5V68/qmZTbJWq8wqdZtjELkZtNcQQX4x8EToShbn5nitG3RA4=
 }
+
+func ExampleManageBuyOffer() {
+	kp, _ := keypair.Parse("SBZVMB74Z76QZ3ZOY7UTDFYKMEGKW5XFJEB6PFKBF4UYSSWHG4EDH7PY")
+	client := horizonclient.DefaultTestNetClient
+	ar := horizonclient.AccountRequest{AccountID: kp.Address()}
+	sourceAccount, err := client.AccountDetail(ar)
+	check(err)
+
+	buyOffer := ManageBuyOffer{
+		Selling: NativeAsset{},
+		Buying:  CreditAsset{"ABCD", "GDQNY3PBOJOKYZSRMK2S7LHHGWZIUISD4QORETLMXEWXBI7KFZZMKTL3"},
+		Amount:  "100",
+		Price:   "0.01",
+		OfferID: 0,
+	}
+
+	tx := Transaction{
+		SourceAccount: &sourceAccount,
+		Operations:    []Operation{&buyOffer},
+		Timebounds:    NewInfiniteTimeout(),
+		Network:       network.TestNetworkPassphrase,
+	}
+
+	txe, err := tx.BuildSignEncode(kp.(*keypair.Full))
+	check(err)
+	fmt.Println(txe)
+
+	// Output: AAAAAH4RyzTWNfXhqwLUoCw91aWkZtgIzY8SAVkIPc0uFVmYAAAAZAAMoj8AAAAEAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAAODcbeFyXKxmUWK1L6znNbKKIkPkHRJNbLktcKPqLnLFAAAAADuaygAAAAABAAAAZAAAAAAAAAAAAAAAAAAAAAEuFVmYAAAAQPh8h1TrzDpcgzB/VE8V0X2pFGV8/JyuYrx0I5bRfBJuLJr0l8yL1isP1wZjvMdX7fNiktwSLuUuj749nWA6wAo=
+
+}

txnbuild/manage_buy_offer.go

@@ -0,0 +1,59 @@
+package txnbuild
+
+import (
+	"github.com/stellar/go/amount"
+	"github.com/stellar/go/price"
+	"github.com/stellar/go/support/errors"
+	"github.com/stellar/go/xdr"
+)
+
+// ManageBuyOffer represents the Stellar manage buy offer operation. See
+// https://www.stellar.org/developers/guides/concepts/list-of-operations.html
+type ManageBuyOffer struct {
+	Selling       Asset
+	Buying        Asset
+	Amount        string
+	Price         string
+	OfferID       int64
+	SourceAccount Account
+}
+
+// BuildXDR for ManageBuyOffer returns a fully configured XDR Operation.
+func (mo *ManageBuyOffer) BuildXDR() (xdr.Operation, error) {
+	xdrSelling, err := mo.Selling.ToXDR()
+	if err != nil {
+		return xdr.Operation{}, errors.Wrap(err, "failed to set XDR 'Selling' field")
+	}
+
+	xdrBuying, err := mo.Buying.ToXDR()
+	if err != nil {
+		return xdr.Operation{}, errors.Wrap(err, "failed to set XDR 'Buying' field")
+	}
+
+	xdrAmount, err := amount.Parse(mo.Amount)
+	if err != nil {
+		return xdr.Operation{}, errors.Wrap(err, "failed to parse 'Amount'")
+	}
+
+	xdrPrice, err := price.Parse(mo.Price)
+	if err != nil {
+		return xdr.Operation{}, errors.Wrap(err, "failed to parse 'Price'")
+	}
+
+	opType := xdr.OperationTypeManageBuyOffer
+	xdrOp := xdr.ManageBuyOfferOp{
+		Selling:   xdrSelling,
+		Buying:    xdrBuying,
+		BuyAmount: xdrAmount,
+		Price:     xdrPrice,
+		OfferId:   xdr.Int64(mo.OfferID),
+	}
+	body, err := xdr.NewOperationBody(opType, xdrOp)
+	if err != nil {
+		return xdr.Operation{}, errors.Wrap(err, "failed to build XDR OperationBody")
+	}
+
+	op := xdr.Operation{Body: body}
+	SetOpSourceAccount(&op, mo.SourceAccount)
+	return op, nil
+}

txnbuild/transaction_test.go

@@ -632,3 +632,79 @@ func TestMemoReturn(t *testing.T) {
 	expected := "AAAAAH4RyzTWNfXhqwLUoCw91aWkZtgIzY8SAVkIPc0uFVmYAAAAZAAMLgoAAAABAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAEAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAABAAAAAAAAAAsAAAAAAAAAAQAAAAAAAAABLhVZmAAAAEAuLFTunY08pbWKompoepHdazLmr7uePUSOzA4P33+SVRKWiu+h2tngOsP8hga+wpLJXT9l/0uMQ3iziRVUrh0K"
 	assert.Equal(t, expected, received, "Base 64 XDR should match")
 }
+
+func TestManageBuyOfferNewOffer(t *testing.T) {
+	kp0 := newKeypair0()
+	kp1 := newKeypair1()
+	sourceAccount := NewSimpleAccount(kp1.Address(), int64(41137196761092))
+
+	buyOffer := ManageBuyOffer{
+		Selling: NativeAsset{},
+		Buying:  CreditAsset{"ABCD", kp0.Address()},
+		Amount:  "100",
+		Price:   "0.01",
+		OfferID: 0,
+	}
+
+	tx := Transaction{
+		SourceAccount: &sourceAccount,
+		Operations:    []Operation{&buyOffer},
+		Timebounds:    NewInfiniteTimeout(),
+		Network:       network.TestNetworkPassphrase,
+	}
+
+	received := buildSignEncode(t, tx, kp1)
+	// https://www.stellar.org/laboratory/#xdr-viewer?input=AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R%2BAAAAZAAAJWoAAAAFAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAAODcbeFyXKxmUWK1L6znNbKKIkPkHRJNbLktcKPqLnLFAAAAADuaygAAAAABAAAAZAAAAAAAAAAAAAAAAAAAAAHSh2R%2BAAAAQHwuorW7BvBwJAz%2BETSteeDZ9UKhox1y1BqJLvaIkWSr5rNbOpimjWQxrUNQoy%2B%2BwmtY8tiMSv3Jbz8Dd4QTaQU%3D&type=TransactionEnvelope&network=test
+	expected := "AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R+AAAAZAAAJWoAAAAFAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAAODcbeFyXKxmUWK1L6znNbKKIkPkHRJNbLktcKPqLnLFAAAAADuaygAAAAABAAAAZAAAAAAAAAAAAAAAAAAAAAHSh2R+AAAAQHwuorW7BvBwJAz+ETSteeDZ9UKhox1y1BqJLvaIkWSr5rNbOpimjWQxrUNQoy++wmtY8tiMSv3Jbz8Dd4QTaQU="
+	assert.Equal(t, expected, received, "Base 64 XDR should match")
+}
+
+func TestManageBuyOfferDeleteOffer(t *testing.T) {
+	kp1 := newKeypair1()
+	sourceAccount := NewSimpleAccount(kp1.Address(), int64(41137196761105))
+
+	buyOffer := ManageBuyOffer{
+		Selling: NativeAsset{},
+		Buying:  CreditAsset{"ABCD", kp1.Address()},
+		Amount:  "0",
+		Price:   "0.01",
+		OfferID: int64(2921622),
+	}
+
+	tx := Transaction{
+		SourceAccount: &sourceAccount,
+		Operations:    []Operation{&buyOffer},
+		Timebounds:    NewInfiniteTimeout(),
+		Network:       network.TestNetworkPassphrase,
+	}
+
+	received := buildSignEncode(t, tx, kp1)
+	// https://www.stellar.org/laboratory/#xdr-viewer?input=AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R%2BAAAAZAAAJWoAAAASAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R%2BAAAAAAAAAAAAAAABAAAAZAAAAAAALJSWAAAAAAAAAAHSh2R%2BAAAAQItno%2BcpmUYFvxLcYVaDonTV3dmvzz%2B2SLzKRrYoXOqK8wCZjcP%2FkgzPMmXhTtF2tgQ9qb0rAIYpH9%2FrjtZPBgY%3D&type=TransactionEnvelope&network=test
+	expected := "AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R+AAAAZAAAJWoAAAASAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R+AAAAAAAAAAAAAAABAAAAZAAAAAAALJSWAAAAAAAAAAHSh2R+AAAAQItno+cpmUYFvxLcYVaDonTV3dmvzz+2SLzKRrYoXOqK8wCZjcP/kgzPMmXhTtF2tgQ9qb0rAIYpH9/rjtZPBgY="
+	assert.Equal(t, expected, received, "Base 64 XDR should match")
+}
+
+func TestManageBuyOfferUpdateOffer(t *testing.T) {
+	kp1 := newKeypair1()
+	sourceAccount := NewSimpleAccount(kp1.Address(), int64(41137196761097))
+
+	buyOffer := ManageBuyOffer{
+		Selling: NativeAsset{},
+		Buying:  CreditAsset{"ABCD", kp1.Address()},
+		Amount:  "50",
+		Price:   "0.02",
+		OfferID: int64(2921622),
+	}
+
+	tx := Transaction{
+		SourceAccount: &sourceAccount,
+		Operations:    []Operation{&buyOffer},
+		Timebounds:    NewInfiniteTimeout(),
+		Network:       network.TestNetworkPassphrase,
+	}
+
+	received := buildSignEncode(t, tx, kp1)
+	// https://www.stellar.org/laboratory/#xdr-viewer?input=AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R%2BAAAAZAAAJWoAAAAKAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R%2BAAAAAB3NZQAAAAABAAAAMgAAAAAALJSWAAAAAAAAAAHSh2R%2BAAAAQK%2FsasTxgNqvkz3dGaDOyUgfa9UAAmUBmgiyaQU1dMlNNvTVH1D7PQKXkTooWmb6qK7Ee8vaTCFU6gGmShhA9wE%3D&type=TransactionEnvelope&network=test
+	expected := "AAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R+AAAAZAAAJWoAAAAKAAAAAQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAQAAAAAAAAAMAAAAAAAAAAFBQkNEAAAAACXK8doPx27P6IReQlRRuweSSUiUfjqgyswxiu3Sh2R+AAAAAB3NZQAAAAABAAAAMgAAAAAALJSWAAAAAAAAAAHSh2R+AAAAQK/sasTxgNqvkz3dGaDOyUgfa9UAAmUBmgiyaQU1dMlNNvTVH1D7PQKXkTooWmb6qK7Ee8vaTCFU6gGmShhA9wE="
+	assert.Equal(t, expected, received, "Base 64 XDR should match")
+}