Add web API (fix #17)

Makefile

@@ -1,16 +1,16 @@
-NAME =		number-to-words
+PACKAGES =	$(notdir $(wildcard ./cmd/*))
 SOURCE :=	$(shell find . -name "*.go")
 
 
 all: build
 
 
-$(NAME): $(SOURCE)
-	go build -o ./$(NAME) ./cmd/$(NAME)/main.go
+$(PACKAGES): $(SOURCE)
+	go install -v ./cmd/$@
 
 
 .PHONY: build
-build: $(NAME)
+build: $(PACKAGES)
 
 
 .PHONY: docker

cmd/ntw-web/main.go

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"net/http"
+	"os"
+	"path"
+	"strconv"
+
+	"github.com/apex/log"
+	"github.com/gorilla/mux"
+	"github.com/moul/number-to-words"
+	"github.com/urfave/cli"
+)
+
+func main() {
+	app := cli.NewApp()
+	app.Name = path.Base(os.Args[0])
+	app.Author = "Manfred Touron"
+	app.Email = "https://github.com/moul/number-to-words"
+	app.Version = ntw.Version
+	app.Usage = "number to number web API"
+
+	app.Flags = []cli.Flag{
+		cli.StringFlag{
+			Name:  "bind, b",
+			Usage: "HTTP bind address",
+			Value: ":8000",
+		},
+	}
+	app.Action = server
+	app.Run(os.Args)
+}
+
+func server(c *cli.Context) error {
+	r := mux.NewRouter()
+	r.HandleFunc("/{lang}/{number}", func(w http.ResponseWriter, r *http.Request) {
+		vars := mux.Vars(r)
+
+		number, err := strconv.Atoi(vars["number"])
+		if err != nil {
+			w.WriteHeader(http.StatusBadRequest)
+			fmt.Fprintf(w, "invalid input number %q: %v\n", vars["number"], err)
+			return
+		}
+
+		var output string
+		switch vars["lang"] {
+		case "en", "english":
+			output = ntw.IntegerToEnglish(number)
+		case "fr", "french":
+			output = ntw.IntegerToFrench(number)
+		case "it", "italian":
+			output = ntw.IntegerToItalian(number)
+		case "es", "spanish":
+			output = ntw.IntegerToSpanish(number)
+		case "se", "swedish":
+			output = ntw.IntegerToSpanish(number)
+		case "nl", "dutch":
+			output = ntw.IntegerToSpanish(number)
+		case "roman":
+			output = ntw.IntegerToRoman(number)
+		case "roman-unicode":
+			output = ntw.IntegerToUnicodeRoman(number)
+		case "aegean":
+			output = ntw.IntegerToAegean(number)
+		default:
+			w.WriteHeader(http.StatusNotFound)
+			fmt.Fprintf(w, "no such language %q\n", vars["lang"])
+			return
+		}
+		w.WriteHeader(http.StatusOK)
+		fmt.Fprintf(w, "%s\n", output)
+	})
+	log.Infof("Listening to %s", c.String("bind"))
+	return http.ListenAndServe(c.String("bind"), r)
+}