Transactions Memo

TODO

@@ -1,7 +1,7 @@
 # mint
 
-  [ ] allow cancellation from hop 0 by attempted propagation to last node
-  [ ] transaction reference and metadata
+  [ ] allow cancellation from hop k<n by attempted propagation to last node
+  [ ] transaction memo
   [ ] async webhooks
     [ ] asset.created
     [ ] balance.updated

mint/endpoint/create_transaction.go

@@ -44,6 +44,7 @@ type CreateTransaction struct {
 	Amount      big.Int
 	Destination string
 	Path        []string
+	Memo        *string
 
 	// State
 	Tx   *model.Transaction
@@ -133,6 +134,13 @@ func (e *CreateTransaction) Validate(
 			return errors.Trace(err)
 		}
 		e.Path = path
+
+		// Validate memo.
+		memo, err := ValidateMemo(ctx, r.PostFormValue("memo"))
+		if err != nil {
+			return errors.Trace(err)
+		}
+		e.Memo = memo
 	}
 
 	return nil
@@ -172,6 +180,7 @@ func (e *CreateTransaction) ExecuteCanonical(
 		e.Destination,
 		model.OfPath(e.Path),
 		mint.TxStPending,
+		e.Memo,
 	)
 	if err != nil {
 		return nil, nil, errors.Trace(err) // 500
@@ -326,6 +335,7 @@ func (e *CreateTransaction) ExecutePropagated(
 			model.OfPath(e.Path),
 			mint.TxStPending,
 			transaction.Lock,
+			transaction.Memo,
 		)
 		if err != nil {
 			return nil, nil, errors.Trace(err) // 500

mint/endpoint/validations.go

@@ -259,3 +259,22 @@ func ValidatePropagation(
 
 	return &p, nil
 }
+
+// ValidateMemo validates a memo.
+func ValidateMemo(
+	ctx context.Context,
+	memo string,
+) (*string, error) {
+	if int64(len(memo)) > mint.MemoMaxLength {
+		return nil, errors.Trace(errors.NewUserErrorf(nil,
+			400, "memo_invalid",
+			"The memo you provided exceeds the maximum length (%d): %s.",
+			mint.MemoMaxLength, memo,
+		))
+	}
+
+	if len(memo) == 0 {
+		return nil, nil
+	}
+	return &memo, nil
+}

mint/model/schemas/mint.5.transactions.go

@@ -20,6 +20,8 @@ CREATE TABLE IF NOT EXISTS transactions(
   lock VARCHAR(256) NOT NULL,        -- lock = hex(scrypt(secret, id))
   secret VARCHAR(256),               -- lock secret
 
+  memo VARCHAR(1024),                -- memo
+
   PRIMARY KEY(owner, token)
 );
 `

mint/model/transaction.go

@@ -35,6 +35,8 @@ type Transaction struct {
 
 	Lock   string
 	Secret *string
+
+	Memo *string
 }
 
 // NewTransactionResource generates a new resource.
@@ -57,6 +59,7 @@ func NewTransactionResource(
 		Path:        []string(transaction.Path),
 		Status:      transaction.Status,
 		Lock:        transaction.Lock,
+		Memo:        transaction.Memo,
 		Operations:  []mint.OperationResource{},
 		Crossings:   []mint.CrossingResource{},
 	}
@@ -84,6 +87,7 @@ func CreateCanonicalTransaction(
 	destination string,
 	path []string,
 	status mint.TxStatus,
+	memo *string,
 ) (*Transaction, error) {
 	tok := token.New("transaction")
 
@@ -109,16 +113,18 @@ func CreateCanonicalTransaction(
 
 		Lock:   lock,
 		Secret: &secret,
+
+		Memo: memo,
 	}
 
 	ext := db.Ext(ctx, "mint")
 	if _, err := sqlx.NamedExec(ext, `
 INSERT INTO transactions
   (owner, token, created, propagation, base_asset, quote_asset,
-   amount, destination, path, status, lock, secret)
+   amount, destination, path, status, lock, secret, memo)
 VALUES
   (:owner, :token, :created, :propagation, :base_asset, :quote_asset,
-   :amount, :destination, :path, :status,  :lock, :secret)
+   :amount, :destination, :path, :status,  :lock, :secret, :memo)
 `, transaction); err != nil {
 		switch err := err.(type) {
 		case *pq.Error:
@@ -150,6 +156,7 @@ func CreatePropagatedTransaction(
 	path []string,
 	status mint.TxStatus,
 	lock string,
+	memo *string,
 ) (*Transaction, error) {
 	transaction := Transaction{
 		Owner:       owner,
@@ -165,16 +172,17 @@ func CreatePropagatedTransaction(
 		Status:      status,
 		Lock:        lock,
 		Secret:      nil,
+		Memo:        memo,
 	}
 
 	ext := db.Ext(ctx, "mint")
 	if _, err := sqlx.NamedExec(ext, `
 INSERT INTO transactions
   (owner, token, created, propagation, base_asset, quote_asset,
-   amount, destination, path, status, lock, secret)
+   amount, destination, path, status, lock, secret, memo)
 VALUES
   (:owner, :token, :created, :propagation, :base_asset, :quote_asset,
-   :amount, :destination, :path, :status, :lock, :secret)
+  :amount, :destination, :path, :status, :lock, :secret, :memo)
 `, transaction); err != nil {
 		switch err := err.(type) {
 		case *pq.Error:

mint/protocol.go

@@ -11,6 +11,8 @@ const (
 	// TransactionExpiryMs is the time it takes to attempt to cancel a
 	// transaction for this mint. Expressed in ms.
 	TransactionExpiryMs int64 = 1000 * 60 * 60
+	// MemoMaxLength is the maximal length of a transaction's memo string.
+	MemoMaxLength int64 = 1024
 )
 
 // PgType is the propagation type of an object.
@@ -140,6 +142,8 @@ type TransactionResource struct {
 	Lock   string   `json:"lock"`
 	Secret *string  `json:"secret"`
 
+	Memo *string `json:"memo"`
+
 	Operations []OperationResource `json:"operations"`
 	Crossings  []CrossingResource  `json:"crossings"`
 }

mint/test/functional/create_transaction_test.go

@@ -70,6 +70,7 @@ func TestCreateTransactionWith2Offers(
 			"pair":        {fmt.Sprintf("%s/%s", a[0].Name, a[2].Name)},
 			"amount":      {"10"},
 			"destination": {u[2].Address},
+			"memo":        {"test-20162017"},
 			"path[]": {
 				o[1].ID,
 				o[2].ID,
@@ -111,6 +112,7 @@ func TestCreateTransactionWith2Offers(
 	assert.Equal(t, mint.TxStReserved, tx0.Operations[0].Status)
 	assert.Equal(t, tx0.ID, *tx0.Operations[0].Transaction)
 	assert.Equal(t, int8(0), *tx0.Operations[0].TransactionHop)
+	assert.Equal(t, "test-20162017", *tx0.Memo)
 
 	// Check transaction on m[1].
 	status, raw = m[1].Get(t, nil, fmt.Sprintf("/transactions/%s", tx0.ID))
@@ -162,6 +164,7 @@ func TestCreateTransactionWith2Offers(
 	assert.Equal(t, mint.TxStReserved, tx1.Operations[0].Status)
 	assert.Equal(t, tx1.ID, *tx1.Operations[0].Transaction)
 	assert.Equal(t, int8(1), *tx1.Operations[0].TransactionHop)
+	assert.Equal(t, "test-20162017", *tx1.Memo)
 
 	// Check transaction on m[2].
 	status, raw = m[2].Get(t, nil, fmt.Sprintf("/transactions/%s", tx0.ID))
@@ -213,6 +216,7 @@ func TestCreateTransactionWith2Offers(
 	assert.Equal(t, mint.TxStReserved, tx2.Operations[0].Status)
 	assert.Equal(t, tx2.ID, *tx2.Operations[0].Transaction)
 	assert.Equal(t, int8(2), *tx2.Operations[0].TransactionHop)
+	assert.Equal(t, "test-20162017", *tx2.Memo)
 }
 
 func TestCreateTransactionWithInsufficientOfferAmount(
@@ -351,6 +355,7 @@ func TestCreateTransactionWith1Offer(
 	assert.Equal(t, big.NewInt(10), tx0.Operations[0].Amount)
 	assert.Equal(t, u[1].Address, tx0.Operations[0].Destination)
 	assert.Equal(t, u[0].Address, tx0.Operations[0].Source)
+	assert.Nil(t, tx0.Memo)
 
 	// Check transaction on m[1].
 	status, raw = m[1].Get(t, nil, fmt.Sprintf("/transactions/%s", tx0.ID))
@@ -373,6 +378,7 @@ func TestCreateTransactionWith1Offer(
 	assert.Equal(t, mint.TxStReserved, tx1.Operations[0].Status)
 	assert.Equal(t, tx1.ID, *tx1.Operations[0].Transaction)
 	assert.Equal(t, int8(1), *tx1.Operations[0].TransactionHop)
+	assert.Nil(t, tx1.Memo)
 }
 
 func TestCreateTransactionWithRemoteBaseAsset(

mint/test/functional/settle_transaction_test.go

@@ -268,6 +268,7 @@ func TestSettleTransactionWithRemoteBaseAsset(
 			"pair":        {fmt.Sprintf("%s/%s", a[1].Name, a[2].Name)},
 			"amount":      {"10"},
 			"destination": {u[2].Address},
+			"memo":        {"test-20162017"},
 			"path[]": {
 				o[2].ID,
 			},
@@ -291,6 +292,7 @@ func TestSettleTransactionWithRemoteBaseAsset(
 	assert.Equal(t, mint.TxStSettled, tx0.Status)
 	assert.Equal(t, 0, len(tx0.Operations))
 	assert.Equal(t, 0, len(tx0.Crossings))
+	assert.Equal(t, "test-20162017", *tx0.Memo)
 
 	// Check transaction on m[1].
 	status, raw = m[1].Get(t, nil, fmt.Sprintf("/transactions/%s", tx0.ID))
@@ -303,6 +305,7 @@ func TestSettleTransactionWithRemoteBaseAsset(
 	assert.Equal(t, mint.TxStSettled, tx1.Status)
 	assert.Equal(t, 0, len(tx1.Crossings))
 	assert.Equal(t, 1, len(tx1.Operations))
+	assert.Equal(t, "test-20162017", *tx1.Memo)
 
 	assert.Equal(t, mint.TxStSettled, tx1.Operations[0].Status)
 
@@ -317,6 +320,7 @@ func TestSettleTransactionWithRemoteBaseAsset(
 	assert.Equal(t, mint.TxStSettled, tx2.Status)
 	assert.Equal(t, 1, len(tx2.Crossings))
 	assert.Equal(t, 1, len(tx2.Operations))
+	assert.Equal(t, "test-20162017", *tx2.Memo)
 
 	assert.Equal(t, mint.TxStSettled, tx2.Crossings[0].Status)
 	assert.Equal(t, mint.TxStSettled, tx2.Operations[0].Status)