feat(api): implement new api handler

pkg/api/router.go

@@ -0,0 +1,34 @@
+package api
+
+import (
+	. "github.com/containrrr/watchtower/pkg/api/prelude"
+	"net/http"
+)
+
+type router map[string]methodHandlers
+
+type methodHandlers map[string]HandlerFunc
+
+func (mh methodHandlers) Handler(c *Context) Response {
+	handler, found := mh[c.Request.Method]
+	if !found {
+		return Error(ErrNotFound)
+	}
+	return handler(c)
+}
+
+func (mh methodHandlers) post(handlerFunc HandlerFunc) {
+	mh[http.MethodPost] = handlerFunc
+}
+func (mh methodHandlers) get(handlerFunc HandlerFunc) {
+	mh[http.MethodGet] = handlerFunc
+}
+
+func (r router) route(route string) methodHandlers {
+	routeMethods, found := r[route]
+	if !found {
+		routeMethods = methodHandlers{}
+		r[route] = routeMethods
+	}
+	return routeMethods
+}