From 3118ac0a8e2a42fb54ae102fba58559125e2848b Mon Sep 17 00:00:00 2001
From: Simon Ser <contact@emersion.fr>
Date: Tue, 20 Feb 2024 12:18:14 +0100
Subject: [PATCH] Add server name config directive

References: https://todo.sr.ht/~emersion/sinwon/24

---
 client.go                   | 10 ++++------
 config.go                   |  5 +++--
 config.in                   |  1 +
 main.go                     | 12 ++++++++++--
 middleware.go               | 44 +++++++++++++++++++++++++++++++++++++++++---
 oauth2.go                   |  5 ++---
 template/authorize.html     |  4 ++--
 template/client-secret.html |  4 ++--
 template/head.html          |  2 +-
 template/index.html         |  4 ++--
 template/login.html         |  4 ++--
 template/manage-client.html |  4 ++--
 template/manage-user.html   |  4 ++--
 user.go                     | 18 ++++++------------

diff --git a/client.go b/client.go
index dc7068584a0214a9f3da35700fcd980560f082c2..692132ac77744eb23cc34a15fc22d8ed0e901a5d 100644
--- a/client.go
+++ b/client.go
@@ -46,13 +46,12 @@ 	}
 
 	if req.Method != http.MethodPost {
 		data := struct {
+			TemplateBaseData
 			Client *Client
 		}{
 			Client: client,
 		}
-		if err := tpl.ExecuteTemplate(w, "manage-client.html", &data); err != nil {
-			panic(err)
-		}
+		tpl.MustExecuteTemplate(w, "manage-client.html", &data)
 		return
 	}
 
@@ -107,15 +106,14 @@ 		return
 	}
 
 	data := struct {
+		TemplateBaseData
 		ClientID     string
 		ClientSecret string
 	}{
 		ClientID:     client.ClientID,
 		ClientSecret: clientSecret,
 	}
-	if err := tpl.ExecuteTemplate(w, "client-secret.html", &data); err != nil {
-		panic(err)
-	}
+	tpl.MustExecuteTemplate(w, "client-secret.html", &data)
 }
 
 func validateAllowedRedirectURIs(rawRedirectURIs string) error {
diff --git a/config.go b/config.go
index 2d3067b1a4e1146c315dc5f4cb4932ac9ff160a3..6fb7bc68b139d296d03cebd330169e92ac38ccf2 100644
--- a/config.go
+++ b/config.go
@@ -7,8 +7,9 @@ 	"git.sr.ht/~emersion/go-scfg"
 )
 
 type Config struct {
-	Listen   string `scfg:"listen"`
-	Database string `scfg:"database"`
+	Listen     string `scfg:"listen"`
+	Database   string `scfg:"database"`
+	ServerName string `scfg:"server-name"`
 }
 
 func loadConfig(filename string) (*Config, error) {
diff --git a/config.in b/config.in
index 553d581940f6aee43f62285a3ef11ced9401af75..4a230b50954c003ac53269cdfbb5fccf0689cb01 100644
--- a/config.in
+++ b/config.in
@@ -1,2 +1,3 @@
 listen localhost:8080
 database /var/lib/sinwon/main.db
+server-name sinwon
diff --git a/main.go b/main.go
index 11997a10f89c21321ecb48d55d88b07fe0852bd7..f03843566a59f1193f30a11671a51822c698352b 100644
--- a/main.go
+++ b/main.go
@@ -4,7 +4,6 @@ import (
 	"context"
 	"embed"
 	"flag"
-	"html/template"
 	"log"
 	"net"
 	"net/http"
@@ -46,7 +45,16 @@ 	if err != nil {
 		log.Fatalf("Failed to open DB: %v", err)
 	}
 
-	tpl := template.Must(template.ParseFS(templateFS, "template/*.html"))
+	tplBaseData := &TemplateBaseData{
+		ServerName: cfg.ServerName,
+	}
+	if tplBaseData.ServerName == "" {
+		tplBaseData.ServerName = "sinwon"
+	}
+	tpl, err := loadTemplate(templateFS, "template/*.html", tplBaseData)
+	if err != nil {
+		log.Fatalf("Failed to load template: %v", err)
+	}
 
 	mux := chi.NewRouter()
 	mux.Handle("/static/*", http.FileServer(http.FS(staticFS)))
diff --git a/middleware.go b/middleware.go
index 2d313b9c4b3e14f17dba52ee7bd79b1ed2e41243..09810b6e71ec1878a8173a68ba709cfd18f2f3f6 100644
--- a/middleware.go
+++ b/middleware.go
@@ -4,6 +4,8 @@ import (
 	"context"
 	"fmt"
 	"html/template"
+	"io"
+	"io/fs"
 	"mime"
 	"net/http"
 )
@@ -25,8 +27,8 @@ func dbFromContext(ctx context.Context) *DB {
 	return ctx.Value(contextKeyDB).(*DB)
 }
 
-func templateFromContext(ctx context.Context) *template.Template {
-	return ctx.Value(contextKeyTemplate).(*template.Template)
+func templateFromContext(ctx context.Context) *Template {
+	return ctx.Value(contextKeyTemplate).(*Template)
 }
 
 func loginTokenFromContext(ctx context.Context) *AccessToken {
@@ -37,7 +39,7 @@ 	}
 	return v.(*AccessToken)
 }
 
-func newBaseContext(db *DB, tpl *template.Template) context.Context {
+func newBaseContext(db *DB, tpl *Template) context.Context {
 	ctx := context.Background()
 	ctx = context.WithValue(ctx, contextKeyDB, db)
 	ctx = context.WithValue(ctx, contextKeyTemplate, tpl)
@@ -109,3 +111,39 @@ 		req = req.WithContext(ctx)
 		next.ServeHTTP(w, req)
 	})
 }
+
+type TemplateBaseData struct {
+	ServerName string
+}
+
+func (data *TemplateBaseData) Base() *TemplateBaseData {
+	return data
+}
+
+type TemplateData interface {
+	Base() *TemplateBaseData
+}
+
+type Template struct {
+	tpl      *template.Template
+	baseData *TemplateBaseData
+}
+
+func loadTemplate(fs fs.FS, pattern string, baseData *TemplateBaseData) (*Template, error) {
+	tpl, err := template.ParseFS(fs, pattern)
+	if err != nil {
+		return nil, err
+	}
+	return &Template{tpl: tpl, baseData: baseData}, nil
+}
+
+func (tpl *Template) MustExecuteTemplate(w io.Writer, filename string, data TemplateData) {
+	if data == nil {
+		data = tpl.baseData
+	} else {
+		*data.Base() = *tpl.baseData
+	}
+	if err := tpl.tpl.ExecuteTemplate(w, filename, data); err != nil {
+		panic(err)
+	}
+}
diff --git a/oauth2.go b/oauth2.go
index df37a6a9a4a00f719714517dce2e1e777bdd9406..20e8d25484f675bb1924834394884c225de308d7 100644
--- a/oauth2.go
+++ b/oauth2.go
@@ -148,13 +148,12 @@ 		return
 	}
 	if _, ok := req.PostForm["authorize"]; !ok {
 		data := struct {
+			TemplateBaseData
 			Client *Client
 		}{
 			Client: client,
 		}
-		if err := tpl.ExecuteTemplate(w, "authorize.html", data); err != nil {
-			panic(err)
-		}
+		tpl.MustExecuteTemplate(w, "authorize.html", &data)
 		return
 	}
 
diff --git a/template/authorize.html b/template/authorize.html
index 53be65bc66b71fd3dd174e3ff6e1a4703e5193b9..7c0f525dacb582e2843d317f2acaba9e5a59fba9 100644
--- a/template/authorize.html
+++ b/template/authorize.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <p>
 	Authorize
diff --git a/template/client-secret.html b/template/client-secret.html
index d354b0e24aace063af3c9c6d8c43b4529dd056c2..c0f79bbb903b219cdad1f8c0b1bb5cf7334ba536 100644
--- a/template/client-secret.html
+++ b/template/client-secret.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <p>
 	<strong>Client ID</strong>: <code>{{ .ClientID }}</code><br>
diff --git a/template/head.html b/template/head.html
index 4e67adfceb075951639c24ee864f07857f08bcbe..a36f23450c00bee71bba1c80d9883e155ef8025f 100644
--- a/template/head.html
+++ b/template/head.html
@@ -2,7 +2,7 @@ <!DOCTYPE HTML>
 <html lang="en">
 <head>
     <meta charset="utf-8"/>
-    <title>sinwon</title>
+	<title>{{ .ServerName }}</title>
     <meta name="viewport" content="width=device-width, initial-scale=1"/>
     <link rel="stylesheet" href="/static/style.css"/>
 </head>
diff --git a/template/index.html b/template/index.html
index da8b6b68d94449bbd66bcb8612fdb592e08cbd49..1b27564b32a0df2cff9ecd5d946b75fd44aca382 100644
--- a/template/index.html
+++ b/template/index.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <p>Welcome, {{ .Me.Username }}!</p>
 
diff --git a/template/login.html b/template/login.html
index 9f93f2a41a411a6a8a237c84906d2084360177b0..ab88c5ca0b9086d49fd8a26519a07e4ca398e7fa 100644
--- a/template/login.html
+++ b/template/login.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <form method="post" action="">
 	Username: <input type="text" name="username" autocomplete="username"><br>
diff --git a/template/manage-client.html b/template/manage-client.html
index 082eb9bfebf2fb602cc50b9777249bb95bac03ae..0a78e7620775468d6e3c498e49646a41dc2b8ad3 100644
--- a/template/manage-client.html
+++ b/template/manage-client.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <form method="post" action="">
 	{{ if .Client.ClientID }}
diff --git a/template/manage-user.html b/template/manage-user.html
index 9d599ded2523fa41b79d8bce43b748dfcfe48312..83954eec0efe7d044edce76ec228f60ab8955e59 100644
--- a/template/manage-user.html
+++ b/template/manage-user.html
@@ -1,8 +1,8 @@
-{{ template "head.html" }}
+{{ template "head.html" .Base }}
 
 <main>
 
-<h1>sinwon</h1>
+<h1>{{ .ServerName }}</h1>
 
 <form method="post" action="">
 	Username: <input type="text" name="username" value="{{ .User.Username }}" required><br>
diff --git a/user.go b/user.go
index 6b9c9b44217c38a369e00b0fa15d060c20dfbe7a..e91e64e58363ce84356717d8b18eb6b40b0162e5 100644
--- a/user.go
+++ b/user.go
@@ -49,6 +49,7 @@ 		}
 	}
 
 	data := struct {
+		TemplateBaseData
 		Me                *User
 		AuthorizedClients []AuthorizedClient
 		Clients           []Client
@@ -59,9 +60,7 @@ 		AuthorizedClients: authorizedClients,
 		Clients:           clients,
 		Users:             users,
 	}
-	if err := tpl.ExecuteTemplate(w, "index.html", &data); err != nil {
-		panic(err)
-	}
+	tpl.MustExecuteTemplate(w, "index.html", &data)
 }
 
 func login(w http.ResponseWriter, req *http.Request) {
@@ -89,9 +88,7 @@
 	username := req.PostFormValue("username")
 	password := req.PostFormValue("password")
 	if username == "" {
-		if err := tpl.ExecuteTemplate(w, "login.html", nil); err != nil {
-			panic(err)
-		}
+		tpl.MustExecuteTemplate(w, "login.html", nil)
 		return
 	}
 
@@ -106,9 +103,7 @@ 	}
 	if err != nil {
 		log.Printf("login failed for user %q: %v", username, err)
 		// TODO: show error message
-		if err := tpl.ExecuteTemplate(w, "login.html", nil); err != nil {
-			panic(err)
-		}
+		tpl.MustExecuteTemplate(w, "login.html", nil)
 		return
 	}
 
@@ -186,15 +181,14 @@ 	password := req.PostFormValue("password")
 	admin := req.PostFormValue("admin") == "on"
 	if username == "" {
 		data := struct {
+			TemplateBaseData
 			User *User
 			Me   *User
 		}{
 			User: user,
 			Me:   me,
 		}
-		if err := tpl.ExecuteTemplate(w, "manage-user.html", &data); err != nil {
-			panic(err)
-		}
+		tpl.MustExecuteTemplate(w, "manage-user.html", &data)
 		return
 	}
 

-- 
2.48.1