From 2f05a4573be0a4777c4448936e8520e0087f4bc5 Mon Sep 17 00:00:00 2001
From: William Petit <wpetit@cadoles.com>
Date: Mon, 24 Sep 2018 08:49:21 +0200
Subject: [PATCH] Base implementation of the RPC endpoint

---
 cmd/server/main.go       | 10 +++++++++-
 cmd/server/rpc/server.go | 38 ++++++++++++++++++++++++++++++++++++++
 go.mod                   |  1 +
 go.sum                   |  2 ++
 4 files changed, 50 insertions(+), 1 deletion(-)
 create mode 100644 cmd/server/rpc/server.go

diff --git a/cmd/server/main.go b/cmd/server/main.go
index 452ee3f..44b626d 100644
--- a/cmd/server/main.go
+++ b/cmd/server/main.go
@@ -5,12 +5,14 @@ import (
 	"log"
 	"net/http"
 
+	"forge.cadoles.com/Pyxis/orion/cmd/server/rpc"
 	"github.com/go-chi/chi"
 	"github.com/go-chi/chi/middleware"
 )
 
 var (
-	conf = newDefaultConfig()
+	conf    = newDefaultConfig()
+	jsonrpc = rpc.NewServer()
 )
 
 func main() {
@@ -26,6 +28,8 @@ func main() {
 	r.Use(middleware.RealIP)
 	r.Use(middleware.Logger)
 
+	r.Post("/rpc", handleRPC)
+
 	hostStr := fmt.Sprintf("%s:%s", conf.HTTPHost, conf.HTTPPort)
 	log.Printf("listening on http://%s", hostStr)
 
@@ -34,3 +38,7 @@ func main() {
 	}
 
 }
+
+func handleRPC(w http.ResponseWriter, r *http.Request) {
+	jsonrpc.ServeHTTP(w, r)
+}
diff --git a/cmd/server/rpc/server.go b/cmd/server/rpc/server.go
new file mode 100644
index 0000000..92673c3
--- /dev/null
+++ b/cmd/server/rpc/server.go
@@ -0,0 +1,38 @@
+package rpc
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/gorilla/rpc"
+	"github.com/gorilla/rpc/json"
+)
+
+// OrionService is the JSON-RPC API
+type OrionService struct{}
+
+// HelloArgs is the arguments expected by the Hello method
+type HelloArgs struct {
+	Who string
+}
+
+// HelloResponse is the response returned from the Hello method
+type HelloResponse struct {
+	Message string
+}
+
+// Hello is a demo RPC method fro the OrionService
+func (o *OrionService) Hello(r *http.Request, args *HelloArgs, reply *HelloResponse) error {
+	reply.Message = fmt.Sprintf("hello %s", args.Who)
+	return nil
+}
+
+// NewServer returns a new configured JSON-RPC server
+func NewServer() *rpc.Server {
+	server := rpc.NewServer()
+	server.RegisterCodec(json.NewCodec(), "application/json")
+	if err := server.RegisterService(new(OrionService), "Orion"); err != nil {
+		panic(err)
+	}
+	return server
+}
diff --git a/go.mod b/go.mod
index 4989193..8490b43 100644
--- a/go.mod
+++ b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/cenkalti/backoff v2.0.0+incompatible // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/go-chi/chi v3.3.3+incompatible
+	github.com/gorilla/rpc v1.1.0
 	github.com/gorilla/websocket v1.4.0 // indirect
 	github.com/grandcat/zeroconf v0.0.0-20180329153754-df75bb3ccae1
 	github.com/miekg/dns v1.0.12 // indirect
diff --git a/go.sum b/go.sum
index 63a97cb..c0132ef 100644
--- a/go.sum
+++ b/go.sum
@@ -8,6 +8,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/go-chi/chi v3.3.3+incompatible h1:KHkmBEMNkwKuK4FdQL7N2wOeB9jnIx7jR5wsuSBEFI8=
 github.com/go-chi/chi v3.3.3+incompatible/go.mod h1:eB3wogJHnLi3x/kFX2A+IbTBlXxmMeXJVKy9tTv1XzQ=
+github.com/gorilla/rpc v1.1.0 h1:marKfvVP0Gpd/jHlVBKCQ8RAoUPdX7K1Nuh6l1BNh7A=
+github.com/gorilla/rpc v1.1.0/go.mod h1:V4h9r+4sF5HnzqbwIez0fKSpANP0zlYd3qR7p36jkTQ=
 github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
 github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
 github.com/grandcat/zeroconf v0.0.0-20180329153754-df75bb3ccae1 h1:VSELJSxQlpi1bz4ZwT+93hPpzNLRcgytLr77iVRJpcE=