Support instance-wide OAuth2 applications (#21335)

Support OAuth2 applications created by admins on the admin panel, they
aren't owned by anybody.

Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lauris BH <lauris@nix.lv>

routers/web/admin/applications.go

@@ -0,0 +1,93 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package admin
+
+import (
+	"fmt"
+	"net/http"
+
+	"code.gitea.io/gitea/models/auth"
+	"code.gitea.io/gitea/modules/base"
+	"code.gitea.io/gitea/modules/context"
+	"code.gitea.io/gitea/modules/setting"
+	user_setting "code.gitea.io/gitea/routers/web/user/setting"
+)
+
+var (
+	tplSettingsApplications          base.TplName = "admin/applications/list"
+	tplSettingsOauth2ApplicationEdit base.TplName = "admin/applications/oauth2_edit"
+)
+
+func newOAuth2CommonHandlers() *user_setting.OAuth2CommonHandlers {
+	return &user_setting.OAuth2CommonHandlers{
+		OwnerID:            0,
+		BasePathList:       fmt.Sprintf("%s/admin/applications", setting.AppSubURL),
+		BasePathEditPrefix: fmt.Sprintf("%s/admin/applications/oauth2", setting.AppSubURL),
+		TplAppEdit:         tplSettingsOauth2ApplicationEdit,
+	}
+}
+
+// Applications render org applications page (for org, at the moment, there are only OAuth2 applications)
+func Applications(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("settings.applications")
+	ctx.Data["PageIsAdmin"] = true
+	ctx.Data["PageIsAdminApplications"] = true
+
+	apps, err := auth.GetOAuth2ApplicationsByUserID(ctx, 0)
+	if err != nil {
+		ctx.ServerError("GetOAuth2ApplicationsByUserID", err)
+		return
+	}
+	ctx.Data["Applications"] = apps
+
+	ctx.HTML(http.StatusOK, tplSettingsApplications)
+}
+
+// ApplicationsPost response for adding an oauth2 application
+func ApplicationsPost(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("settings.applications")
+	ctx.Data["PageIsAdmin"] = true
+	ctx.Data["PageIsAdminApplications"] = true
+
+	oa := newOAuth2CommonHandlers()
+	oa.AddApp(ctx)
+}
+
+// EditApplication displays the given application
+func EditApplication(ctx *context.Context) {
+	ctx.Data["PageIsAdmin"] = true
+	ctx.Data["PageIsAdminApplications"] = true
+
+	oa := newOAuth2CommonHandlers()
+	oa.EditShow(ctx)
+}
+
+// EditApplicationPost response for editing oauth2 application
+func EditApplicationPost(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("settings.applications")
+	ctx.Data["PageIsAdmin"] = true
+	ctx.Data["PageIsAdminApplications"] = true
+
+	oa := newOAuth2CommonHandlers()
+	oa.EditSave(ctx)
+}
+
+// ApplicationsRegenerateSecret handles the post request for regenerating the secret
+func ApplicationsRegenerateSecret(ctx *context.Context) {
+	ctx.Data["Title"] = ctx.Tr("settings")
+	ctx.Data["PageIsAdmin"] = true
+	ctx.Data["PageIsAdminApplications"] = true
+
+	oa := newOAuth2CommonHandlers()
+	oa.RegenerateSecret(ctx)
+}
+
+// DeleteApplication deletes the given oauth2 application
+func DeleteApplication(ctx *context.Context) {
+	oa := newOAuth2CommonHandlers()
+	oa.DeleteApp(ctx)
+}
+
+// TODO: revokes the grant with the given id