Add cors support

Author: giansalex

README.md

@@ -11,3 +11,9 @@ make build
 
 ./build/gnoapi
 ```
+
+Custom port and cors enabled.
+
+```
+./build/gnoapi --port 1317 --cors
+```

cmd/main.go

@@ -9,6 +9,7 @@ import (
 	"github.com/gnolang/gno/pkgs/bft/rpc/client"
 
 	"github.com/gorilla/mux"
+	"github.com/rs/cors"
 
 	"github.com/disperze/gno-api/cmd/handler"
 
@@ -19,6 +20,7 @@ import (
 var (
 	remotePtr  = flag.String("remote", "http://gno.land:36657", "Remote rpc")
 	apiPortPtr = flag.String("port", "8888", "Api port")
+	corsPtr    = flag.Bool("cors", false, "Enable CORS")
 )
 
 func main() {
@@ -32,6 +34,12 @@ func main() {
 		log.Fatal("api port is required")
 	}
 
+	c := cors.New(cors.Options{
+		AllowedOrigins: []string{"*"},
+		AllowedMethods: []string{http.MethodGet, http.MethodPost},
+		AllowedHeaders: []string{"Content-Type", "Accept"},
+	})
+
 	apiPort := *apiPortPtr
 	cli := client.NewHTTP(*remotePtr, "/websocket")
 
@@ -45,6 +53,11 @@ func main() {
 	r.HandleFunc("/txs/decode", handler.TxDecodeHandler(cli)).Methods(http.MethodGet)
 	r.HandleFunc("/txs", handler.TxsHandler(cli)).Methods(http.MethodPost)
 
+	var h http.Handler = r
+	if *corsPtr {
+		h = c.Handler(r)
+	}
+
 	fmt.Println("Running on port", apiPort)
-	log.Fatal(http.ListenAndServe(":"+apiPort, r))
+	log.Fatal(http.ListenAndServe(":"+apiPort, h))
 }

go.mod

@@ -5,6 +5,7 @@ go 1.17
 require (
 	github.com/gnolang/gno v0.0.0-20220505214555-31c139670944
 	github.com/gorilla/mux v1.8.0
+	github.com/rs/cors v1.8.2
 )
 
 require (

go.sum

@@ -78,6 +78,8 @@ github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINE
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rivo/uniseg v0.1.0/go.mod h1:J6wj4VEh+S6ZtnVlnTBMWIodfgj8LQOQFoIToxlJtxc=
+github.com/rs/cors v1.8.2 h1:KCooALfAYGs415Cwu5ABvv9n9509fSiG5SQJn/AQo4U=
+github.com/rs/cors v1.8.2/go.mod h1:XyqrcTp5zjWr1wsJ8PIRZssZ8b/WMcMf71DJnit4EMU=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=