Initial commit with cru (no delete) of notes

internal/urls/urls.go

@@ -0,0 +1,47 @@
+// Package to manage routing of urls in net/http
+// URLs type is the main thing of interest
+package urls
+
+import (
+	"fmt"
+	"net/http"
+	"regexp"
+)
+
+// Represent a single URL with a name, a pattern and supported protocol
+type URL struct {
+	Handler  func(http.ResponseWriter, *http.Request)
+	Path     string
+	Protocol string
+}
+
+// Return the corresponding net/http pattern for a URL
+func (url *URL) GetPattern() string {
+	return fmt.Sprintf("%s %s", url.Protocol, url.Path)
+}
+
+// Represent a set of URLs at a prefix
+type URLs struct {
+	URLs   map[string]URL
+	Prefix string
+}
+
+// Given a name and replacements, return a rendered path component of a URL
+func (urls URLs) Reverse(name string, replacements map[string]string) string {
+	pattern := urls.URLs[name].Path
+
+	for key, val := range replacements {
+		re := regexp.MustCompile("{" + key + "}")
+		pattern = re.ReplaceAllString(pattern, val)
+	}
+	return urls.Prefix + pattern
+}
+
+// Return router for the urls
+func (urls URLs) GetRouter() *http.ServeMux {
+	router := http.NewServeMux()
+	for _, url := range urls.URLs {
+		router.HandleFunc(url.GetPattern(), url.Handler)
+	}
+	return router
+}