From ef68be2f38e84c0b3ad7c73dc22ad6be6e197792 Mon Sep 17 00:00:00 2001
From: Matt Bell <mappum@gmail.com>
Date: Mon, 19 Mar 2018 18:13:28 +0100
Subject: [PATCH] Added IBC transfer REST endpoint

---
 client/lcd/root.go     |   2 +
 x/ibc/rest/root.go     |  14 ++++++
 x/ibc/rest/transfer.go | 100 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+)
 create mode 100644 x/ibc/rest/root.go
 create mode 100644 x/ibc/rest/transfer.go

diff --git a/client/lcd/root.go b/client/lcd/root.go
index 7f18af59dc..9464081e0d 100644
--- a/client/lcd/root.go
+++ b/client/lcd/root.go
@@ -20,6 +20,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/wire"
 	auth "github.com/cosmos/cosmos-sdk/x/auth/rest"
 	bank "github.com/cosmos/cosmos-sdk/x/bank/rest"
+	ibc "github.com/cosmos/cosmos-sdk/x/ibc/rest"
 )
 
 const (
@@ -78,5 +79,6 @@ func createHandler(cdc *wire.Codec) http.Handler {
 	tx.RegisterRoutes(r, cdc)
 	auth.RegisterRoutes(r, cdc, "main")
 	bank.RegisterRoutes(r, cdc, kb)
+	ibc.RegisterRoutes(r, cdc, kb)
 	return r
 }
diff --git a/x/ibc/rest/root.go b/x/ibc/rest/root.go
new file mode 100644
index 0000000000..81e74d0312
--- /dev/null
+++ b/x/ibc/rest/root.go
@@ -0,0 +1,14 @@
+package rest
+
+import (
+	"github.com/gorilla/mux"
+
+	keys "github.com/tendermint/go-crypto/keys"
+
+	"github.com/cosmos/cosmos-sdk/wire"
+)
+
+// RegisterRoutes - Central function to define routes that get registered by the main application
+func RegisterRoutes(r *mux.Router, cdc *wire.Codec, kb keys.Keybase) {
+	r.HandleFunc("/ibc/{destchain}/{address}/send", TransferRequestHandler(cdc, kb)).Methods("POST")
+}
diff --git a/x/ibc/rest/transfer.go b/x/ibc/rest/transfer.go
new file mode 100644
index 0000000000..f47159160e
--- /dev/null
+++ b/x/ibc/rest/transfer.go
@@ -0,0 +1,100 @@
+package rest
+
+import (
+	"encoding/hex"
+	"encoding/json"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/gorilla/mux"
+	"github.com/spf13/viper"
+	"github.com/tendermint/go-crypto/keys"
+
+	"github.com/cosmos/cosmos-sdk/client"
+	"github.com/cosmos/cosmos-sdk/client/builder"
+	sdk "github.com/cosmos/cosmos-sdk/types"
+	"github.com/cosmos/cosmos-sdk/wire"
+	"github.com/cosmos/cosmos-sdk/x/bank/commands"
+	"github.com/cosmos/cosmos-sdk/x/ibc"
+)
+
+type transferBody struct {
+	// Fees             sdk.Coin  `json="fees"`
+	Amount           sdk.Coins `json:"amount"`
+	LocalAccountName string    `json:"name"`
+	Password         string    `json:"password"`
+	SrcChainID       string    `json:"src_chain_id"`
+	Sequence         int64     `json:"sequence"`
+}
+
+// TransferRequestHandler - http request handler to transfer coins to a address
+// on a different chain via IBC
+func TransferRequestHandler(cdc *wire.Codec, kb keys.Keybase) func(http.ResponseWriter, *http.Request) {
+	c := commands.Commander{cdc}
+	return func(w http.ResponseWriter, r *http.Request) {
+		// collect data
+		vars := mux.Vars(r)
+		destChainID := vars["destchain"]
+		address := vars["address"]
+
+		var m transferBody
+		body, err := ioutil.ReadAll(r.Body)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write([]byte(err.Error()))
+			return
+		}
+		err = json.Unmarshal(body, &m)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write([]byte(err.Error()))
+			return
+		}
+
+		info, err := kb.Get(m.LocalAccountName)
+		if err != nil {
+			w.WriteHeader(http.StatusUnauthorized)
+			w.Write([]byte(err.Error()))
+			return
+		}
+
+		bz, err := hex.DecodeString(address)
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			w.Write([]byte(err.Error()))
+			return
+		}
+		to := sdk.Address(bz)
+
+		// build message
+		packet := ibc.NewIBCPacket(info.PubKey.Address(), to, m.Amount, m.SrcChainID, destChainID)
+		msg := ibc.IBCTransferMsg{packet}
+
+		// sign
+		// XXX: OMG
+		viper.Set(client.FlagSequence, m.Sequence)
+		txBytes, err := builder.SignAndBuild(m.LocalAccountName, m.Password, msg, c.Cdc)
+		if err != nil {
+			w.WriteHeader(http.StatusUnauthorized)
+			w.Write([]byte(err.Error()))
+			return
+		}
+
+		// send
+		res, err := builder.BroadcastTx(txBytes)
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			w.Write([]byte(err.Error()))
+			return
+		}
+
+		output, err := json.MarshalIndent(res, "", "  ")
+		if err != nil {
+			w.WriteHeader(http.StatusInternalServerError)
+			w.Write([]byte(err.Error()))
+			return
+		}
+
+		w.Write(output)
+	}
+}