Setup first tx, error code

modules/etc/errors.go

@@ -0,0 +1,23 @@
+package etc
+
+import (
+	"fmt"
+
+	abci "github.com/tendermint/abci/types"
+
+	"github.com/tendermint/basecoin/errors"
+)
+
+var (
+	errMissingData = fmt.Errorf("All tx fields must be filled")
+
+	malformed = abci.CodeType_EncodingError
+)
+
+//nolint
+func ErrMissingData() errors.TMError {
+	return errors.WithCode(errMissingData, malformed)
+}
+func IsMissingDataErr(err error) bool {
+	return errors.IsSameError(errMissingData, err)
+}

modules/etc/handler.go

@@ -0,0 +1,6 @@
+package etc
+
+const (
+	// Name of the module for registering it
+	Name = "etc"
+)

modules/etc/store.go

@@ -0,0 +1 @@
+package etc

modules/etc/tx.go

@@ -0,0 +1,41 @@
+package etc
+
+import (
+	"github.com/tendermint/basecoin"
+	"github.com/tendermint/go-wire/data"
+)
+
+// nolint
+const (
+	TypeSet    = Name + "/set"
+	TypeGet    = Name + "/get"
+	TypeRemove = Name + "/remove"
+
+	ByteSet    = 0xF0
+	ByteGet    = 0xF1
+	ByteRemove = 0xF2
+)
+
+func init() {
+	basecoin.TxMapper.
+		RegisterImplementation(SetTx{}, TypeSet, ByteSet)
+}
+
+// SetTx sets a key-value pair
+type SetTx struct {
+	Key   data.Bytes `json:"key"`
+	Value data.Bytes `json:"value"`
+}
+
+// Wrap - fulfills TxInner interface
+func (t SetTx) Wrap() basecoin.Tx {
+	return basecoin.Tx{t}
+}
+
+// ValidateBasic makes sure it is valid
+func (t SetTx) ValidateBasic() error {
+	if len(t.Key) == 0 || len(t.Value) == 0 {
+		return ErrMissingData()
+	}
+	return nil
+}