[feature] New user sign-up via web page (#2796)

* [feature] User sign-up form and admin notifs

* add chosen + filtered languages to migration

* remove stray comment

* chosen languages schmosen schmanguages

* proper error on local account missing

internal/web/signup.go

@@ -0,0 +1,138 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package web
+
+import (
+	"context"
+	"errors"
+	"net"
+
+	"github.com/gin-gonic/gin"
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	apiutil "github.com/superseriousbusiness/gotosocial/internal/api/util"
+	"github.com/superseriousbusiness/gotosocial/internal/config"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/validate"
+)
+
+func (m *Module) signupGETHandler(c *gin.Context) {
+	ctx := c.Request.Context()
+
+	// We'll need the instance later, and we can also use it
+	// before then to make it easier to return a web error.
+	instance, errWithCode := m.processor.InstanceGetV1(ctx)
+	if errWithCode != nil {
+		apiutil.WebErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	// Return instance we already got from the db,
+	// don't try to fetch it again when erroring.
+	instanceGet := func(ctx context.Context) (*apimodel.InstanceV1, gtserror.WithCode) {
+		return instance, nil
+	}
+
+	// We only serve text/html at this endpoint.
+	if _, err := apiutil.NegotiateAccept(c, apiutil.TextHTML); err != nil {
+		apiutil.WebErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), instanceGet)
+		return
+	}
+
+	page := apiutil.WebPage{
+		Template: "sign-up.tmpl",
+		Instance: instance,
+		OGMeta:   apiutil.OGBase(instance),
+		Extra: map[string]any{
+			"reasonRequired": config.GetAccountsReasonRequired(),
+		},
+	}
+
+	apiutil.TemplateWebPage(c, page)
+}
+
+func (m *Module) signupPOSTHandler(c *gin.Context) {
+	ctx := c.Request.Context()
+
+	// We'll need the instance later, and we can also use it
+	// before then to make it easier to return a web error.
+	instance, errWithCode := m.processor.InstanceGetV1(ctx)
+	if errWithCode != nil {
+		apiutil.WebErrorHandler(c, errWithCode, m.processor.InstanceGetV1)
+		return
+	}
+
+	// Return instance we already got from the db,
+	// don't try to fetch it again when erroring.
+	instanceGet := func(ctx context.Context) (*apimodel.InstanceV1, gtserror.WithCode) {
+		return instance, nil
+	}
+
+	// We only serve text/html at this endpoint.
+	if _, err := apiutil.NegotiateAccept(c, apiutil.TextHTML); err != nil {
+		apiutil.WebErrorHandler(c, gtserror.NewErrorNotAcceptable(err, err.Error()), instanceGet)
+		return
+	}
+
+	form := &apimodel.AccountCreateRequest{}
+	if err := c.ShouldBind(form); err != nil {
+		apiutil.WebErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), instanceGet)
+		return
+	}
+
+	if err := validate.CreateAccount(form); err != nil {
+		apiutil.WebErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), instanceGet)
+		return
+	}
+
+	clientIP := c.ClientIP()
+	signUpIP := net.ParseIP(clientIP)
+	if signUpIP == nil {
+		err := errors.New("ip address could not be parsed from request")
+		apiutil.WebErrorHandler(c, gtserror.NewErrorBadRequest(err, err.Error()), instanceGet)
+		return
+	}
+	form.IP = signUpIP
+
+	// We have all the info we need, call account create
+	// (this will also trigger side effects like sending emails etc).
+	user, errWithCode := m.processor.Account().Create(
+		c.Request.Context(),
+		// nil to use
+		// instance app.
+		nil,
+		form,
+	)
+	if errWithCode != nil {
+		apiutil.WebErrorHandler(c, errWithCode, instanceGet)
+		return
+	}
+
+	// Serve a page informing the
+	// user that they've signed up.
+	page := apiutil.WebPage{
+		Template: "signed-up.tmpl",
+		Instance: instance,
+		OGMeta:   apiutil.OGBase(instance),
+		Extra: map[string]any{
+			"email":    user.UnconfirmedEmail,
+			"username": user.Account.Username,
+		},
+	}
+
+	apiutil.TemplateWebPage(c, page)
+}