Moved main to cmd/web and added routes() method

Started to separate out funtionality: added an application struct and
several methods (routes(), home() and a notFound() error).

At the moment, the application struct does not carry any other
configuration objects or a database pool connection - it is just there
to get the routing going.

5 files changed, 46 insertions, 19 deletions

diff --git a/Dockerfile b/Dockerfile
index 50ed167..5196531 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,6 +3,6 @@ WORKDIR /app
 COPY go.mod ./
 RUN go mod download && go mod verify
 COPY . .
-RUN go build -v -o /usr/local/bin/app .
+RUN go build -v -o /usr/local/bin/app ./cmd/web
 CMD ["app"]
 EXPOSE 4000
diff --git a/cmd/web/handlers.go b/cmd/web/handlers.go
new file mode 100644
index 0000000..aed4103
--- /dev/null
+++ b/cmd/web/handlers.go
@@ -0,0 +1,18 @@
+package main
+
+import (
+	"net/http"
+)
+
+func (app *application) notFound(w http.ResponseWriter) {
+	http.Error(w, http.StatusText(401), 401)
+}
+
+func (app *application) home(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path != "/" {
+		app.notFound(w)
+		return
+	}
+
+	w.Write([]byte("Hello from DED"))
+}
diff --git a/cmd/web/main.go b/cmd/web/main.go
new file mode 100644
index 0000000..bd7e500
--- /dev/null
+++ b/cmd/web/main.go
@@ -0,0 +1,17 @@
+package main
+
+import (
+	"log"
+	"net/http"
+)
+
+type application struct{}
+
+func main() {
+	app := &application{}
+	// mux := http.NewServeMux()
+	// mux.HandleFunc("/", home)
+	log.Print("starting server on :4000")
+	err := http.ListenAndServe(":4000", app.routes())
+	log.Fatal(err)
+}
diff --git a/cmd/web/routes.go b/cmd/web/routes.go
new file mode 100644
index 0000000..2761d99
--- /dev/null
+++ b/cmd/web/routes.go
@@ -0,0 +1,10 @@
+package main
+
+import "net/http"
+
+func (app *application) routes() *http.ServeMux {
+	mux := http.NewServeMux()
+
+	mux.HandleFunc("/", app.home)
+	return mux
+}
diff --git a/main.go b/main.go
deleted file mode 100644
index ce89e18..0000000
--- a/main.go
+++ /dev/null
@@ -1,18 +0,0 @@
-package main
-
-import (
-	"log"
-	"net/http"
-)
-
-func home(w http.ResponseWriter, r *http.Request) {
-	w.Write([]byte("Hello from DED"))
-}
-
-func main() {
-	mux := http.NewServeMux()
-	mux.HandleFunc("/", home)
-	log.Print("starting server on :4000")
-	err := http.ListenAndServe(":4000", mux)
-	log.Fatal(err)
-}