Support editing some config values in admin UI

This is almost all of T541

admin.go

@@ -6,8 +6,10 @@ import (
 	"github.com/gorilla/mux"
 	"github.com/writeas/impart"
 	"github.com/writeas/web-core/auth"
+	"github.com/writeas/writefreely/config"
 	"net/http"
 	"runtime"
+	"strconv"
 	"time"
 )
 
@@ -61,14 +63,19 @@ func handleViewAdminDash(app *app, u *User, w http.ResponseWriter, r *http.Reque
 	updateAppStats()
 	p := struct {
 		*UserPage
-		Message   string
 		SysStatus systemStatus
+		Config    config.AppCfg
+
+		Message, ConfigMessage string
 
 		AboutPage, PrivacyPage string
 	}{
 		UserPage:  NewUserPage(app, r, u, "Admin", nil),
-		Message:   r.FormValue("m"),
 		SysStatus: sysStatus,
+		Config:    app.cfg.App,
+
+		Message:       r.FormValue("m"),
+		ConfigMessage: r.FormValue("cm"),
 	}
 
 	var err error
@@ -104,6 +111,29 @@ func handleAdminUpdateSite(app *app, u *User, w http.ResponseWriter, r *http.Req
 	return impart.HTTPError{http.StatusFound, "/admin" + m + "#page-" + id}
 }
 
+func handleAdminUpdateConfig(app *app, u *User, w http.ResponseWriter, r *http.Request) error {
+	app.cfg.App.SiteName = r.FormValue("site_name")
+	app.cfg.App.OpenRegistration = r.FormValue("open_registration") == "on"
+	mul, err := strconv.Atoi(r.FormValue("min_username_len"))
+	if err == nil {
+		app.cfg.App.MinUsernameLen = mul
+	}
+	mb, err := strconv.Atoi(r.FormValue("max_blogs"))
+	if err == nil {
+		app.cfg.App.MaxBlogs = mb
+	}
+	app.cfg.App.Federation = r.FormValue("federation") == "on"
+	app.cfg.App.PublicStats = r.FormValue("public_stats") == "on"
+	app.cfg.App.Private = r.FormValue("private") == "on"
+
+	m := "?cm=Configuration+saved."
+	err = config.Save(app.cfg)
+	if err != nil {
+		m = "?cm=" + err.Error()
+	}
+	return impart.HTTPError{http.StatusFound, "/admin" + m + "#config"}
+}
+
 func updateAppStats() {
 	sysStatus.Uptime = tool.TimeSincePro(appStartTime)
 

routes.go

@@ -116,6 +116,7 @@ func initRoutes(handler *Handler, r *mux.Router, cfg *config.Config, db *datasto
 	write.HandleFunc("/auth/login", handler.Web(webLogin, UserLevelNoneRequired)).Methods("POST")
 
 	write.HandleFunc("/admin", handler.Admin(handleViewAdminDash)).Methods("GET")
+	write.HandleFunc("/admin/update/config", handler.Admin(handleAdminUpdateConfig)).Methods("POST")
 	write.HandleFunc("/admin/update/{page}", handler.Admin(handleAdminUpdateSite)).Methods("POST")
 
 	// Handle special pages first

templates/user/admin.tmpl

@@ -7,6 +7,9 @@ ul.pagenav {list-style: none;}
 form {
 	margin: 0 0 2em;
 }
+form dt {
+	line-height: inherit;
+}
 .ui.divider:not(.vertical):not(.horizontal) {
 	border-top: 1px solid rgba(34,36,38,.15);
 	border-bottom: 1px solid rgba(255,255,255,.1);
@@ -47,6 +50,7 @@ function savePage(el) {
 		<li><a href="#page-privacy">Edit Privacy page</a></li>
 		{{end}}
 		<li><a href="#reset-pass">Reset user password</a></li>
+		<li><a href="#config">Configuration</a></li>
 		<li><a href="#monitor">Application monitor</a></li>
 	</ul>
 
@@ -79,6 +83,38 @@ function savePage(el) {
 
 	<hr />
 
+	<h2><a name="config"></a>App Configuration</h2>
+
+	{{if .ConfigMessage}}<p class="success" style="text-align: center">{{.ConfigMessage}}</p>{{end}}
+
+	<form action="/admin/update/config" method="post">
+	<div class="ui attached table segment">
+		<dl class="dl-horizontal admin-dl-horizontal">
+			<dt>Site Name</dt>
+			<dd><input type="text" name="site_name" id="site_name" class="inline" value="{{.Config.SiteName}}" style="width: 14em;" /></dd>
+			<dt>Host</dt>
+			<dd>{{.Config.Host}}</dd>
+			<dt>User Mode</dt>
+			<dd>{{if .Config.SingleUser}}Single user{{else}}Multiple users{{end}}</dd>
+			<dt><label for="open_registration">Open Registrations</label></dt>
+			<dd><input type="checkbox" name="open_registration" id="open_registration" {{if .Config.OpenRegistration}}checked="checked"{{end}} /></dd>
+			<dt><label for="min_username_len">Minimum Username Length</label></dt>
+			<dd><input type="number" name="min_username_len" id="min_username_len" class="inline" min="1" max="100" value="{{.Config.MinUsernameLen}}" /></dd>
+			<dt><label for="max_blogs">Maximum Blogs per User</label></dt>
+			<dd><input type="number" name="max_blogs" id="max_blogs" class="inline" min="1" value="{{.Config.MaxBlogs}}" /></dd>
+			<dt><label for="federation">Federation</label></dt>
+			<dd><input type="checkbox" name="federation" id="federation" {{if .Config.Federation}}checked="checked"{{end}} /></dd>
+			<dt><label for="public_stats">Public Stats</label></dt>
+			<dd><input type="checkbox" name="public_stats" id="public_stats" {{if .Config.PublicStats}}checked="checked"{{end}} /></dd>
+			<dt><label for="private">Private Instance</label></dt>
+			<dd><input type="checkbox" name="private" id="private" {{if .Config.Private}}checked="checked"{{end}} /></dd>
+		</dl>
+		<input type="submit" value="Save Configuration" />
+	</div>
+	</form>
+
+	<hr />
+
 	<h2><a name="monitor"></a>Application</h2>
 
 	<div class="ui attached table segment">