Add templating

1 files changed, 45 insertions, 0 deletions

diff --git a/templ/template.go b/templ/template.go
new file mode 100644
index 0000000..8fed965
--- /dev/null
+++ b/templ/template.go
@@ -0,0 +1,45 @@
+package templ
+
+import (
+	"embed"
+	"html/template"
+	"sync"
+)
+
+//go:embed *.tpl
+var fs embed.FS
+
+var templates = make(map[string]*template.Template)
+var muTpl sync.RWMutex
+
+var baseTpl *template.Template
+
+func init() {
+	baseTpl = template.Must(template.ParseFS(fs, "base.tpl"))
+}
+
+func Lookup(name string) *template.Template {
+	muTpl.RLock()
+	tpl := templates[name]
+	muTpl.RUnlock()
+
+	if tpl == nil {
+		return parse(name)
+	}
+	return tpl
+}
+
+func parse(name string) *template.Template {
+	muTpl.Lock()
+	defer muTpl.Unlock()
+
+	if tpl := templates[name]; tpl != nil {
+		// might've been created by another goroutine
+		return tpl
+	}
+
+	b := template.Must(baseTpl.Clone())
+	t := template.Must(b.ParseFS(fs, name+".tpl"))
+	templates[name] = t
+	return t
+}