first commit

internal/handler/handler.go

@@ -0,0 +1,125 @@
+// Package handler contains all HTTP request handlers for the paste service.
+package handler
+
+import (
+	"html/template"
+	"log"
+	"net/http"
+	"os"
+	"path/filepath"
+	"time"
+
+	"ridgwaysystems.org/paste/internal/paste"
+)
+
+// Handler holds shared dependencies for all HTTP handlers.
+type Handler struct {
+	store     *paste.Store
+	siteURL   string
+	devMode   bool
+	templates map[string]*template.Template
+}
+
+// New creates a Handler.
+func New(store *paste.Store) *Handler {
+	h := &Handler{
+		store:   store,
+		siteURL: getenv("SITE_URL", "https://paste.ridgwaysystems.org"),
+		devMode: os.Getenv("DEV") == "1",
+	}
+	if !h.devMode {
+		h.templates = mustLoadTemplates()
+	}
+	return h
+}
+
+func getenv(key, def string) string {
+	if v := os.Getenv(key); v != "" {
+		return v
+	}
+	return def
+}
+
+func (h *Handler) tmpl(name string) *template.Template {
+	if h.devMode {
+		return mustLoadTemplates()[name]
+	}
+	return h.templates[name]
+}
+
+func mustLoadTemplates() map[string]*template.Template {
+	m := make(map[string]*template.Template)
+
+	funcMap := template.FuncMap{
+		"formatDate": func(t time.Time) string {
+			if t.IsZero() {
+				return ""
+			}
+			return t.Format("2 January 2006")
+		},
+		"formatDateTime": func(t time.Time) string {
+			if t.IsZero() {
+				return ""
+			}
+			return t.Format("2 Jan 2006 15:04 UTC")
+		},
+		"expiryStr": func(p *paste.Paste) string {
+			if p.ExpiresAt == nil {
+				return "never"
+			}
+			if p.Expired() {
+				return "expired"
+			}
+			return p.ExpiresAt.Format("2 Jan 2006 15:04 UTC")
+		},
+		"isAdmin": func(r *http.Request) bool {
+			return isAuthenticated(r)
+		},
+	}
+
+	base := "templates/base.html"
+
+	pages := []struct {
+		name string
+		file string
+	}{
+		{"list", "templates/list.html"},
+		{"paste", "templates/paste.html"},
+		{"new", "templates/new.html"},
+		{"admin-login", "templates/admin/login.html"},
+		{"admin-dashboard", "templates/admin/dashboard.html"},
+	}
+
+	for _, p := range pages {
+		t, err := template.New(filepath.Base(p.file)).Funcs(funcMap).ParseFiles(base, p.file)
+		if err != nil {
+			log.Fatalf("template %s: %v", p.name, err)
+		}
+		m[p.name] = t
+	}
+
+	return m
+}
+
+// envelope wraps page-specific data for the base template.
+type envelope struct {
+	Inner   any
+	IsAdmin bool
+}
+
+func (h *Handler) render(w http.ResponseWriter, r *http.Request, name string, data any) {
+	t := h.tmpl(name)
+	if t == nil {
+		http.Error(w, "template not found: "+name, http.StatusInternalServerError)
+		return
+	}
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	env := envelope{Inner: data, IsAdmin: isAuthenticated(r)}
+	if err := t.ExecuteTemplate(w, "base", env); err != nil {
+		log.Printf("render %s: %v", name, err)
+	}
+}
+
+func (h *Handler) renderErr(w http.ResponseWriter, code int, msg string) {
+	http.Error(w, msg, code)
+}