add json sample

Author: tenntenn

json/README.md

@@ -0,0 +1,13 @@
+# goji json sample
+
+Run server:
+
+```
+$ go run json.go
+```
+
+Request to the server:
+
+```
+curl http://localhost:8000/hello/gopher
+```

json/json.go

@@ -0,0 +1,34 @@
+package main
+
+import (
+	"encoding/json"
+	"net/http"
+
+	"github.com/zenazn/goji"
+	"github.com/zenazn/goji/web"
+)
+
+type Hello struct {
+	Name string
+	Msg  string
+}
+
+func hello(c web.C, w http.ResponseWriter, r *http.Request) {
+	name := c.URLParams["name"]
+	if name == "" {
+		name = "gopher"
+	}
+
+	hello := &Hello{
+		Name: name,
+		Msg:  "Hello",
+	}
+
+	encoder := json.NewEncoder(w)
+	encoder.Encode(hello)
+}
+
+func main() {
+	goji.Get("/hello/:name", hello)
+	goji.Serve()
+}