registration: Allow import owner to switch to one of imported users.

In case we cannot find a user with email matching with the one
used for preregistration, we ask the import owner which user they
really are.

templates/zerver/realm_import_post_process.html

@@ -0,0 +1,49 @@
+{% extends "zerver/portico_signup.html" %}
+{% set entrypoint = "register" %}
+
+{% block title %}
+<title>{{ _("Finalize organization import") }} | Zulip</title>
+{% endblock %}
+
+{% block portico_content %}
+<div class="app register-page">
+    <div class="app-main register-page-container new-style flex full-page center">
+        <div class="register-form left" id="realm-import-post-process">
+            <div class="lead">
+                <h1 class="get-started">{{ _("Organization import completed!") }}</h1>
+            </div>
+            <div class="white-box">
+                <form method="post" class="form-inline" action="{{ url('realm_import_post_process', args=[key]) }}">
+                    {{ csrf_input }}
+                    <div class="input-box no-validation">
+                        <input type='hidden' name='key' value='{{ key }}' />
+                    </div>
+                    <div class="input-box slack-import-extra-info">
+                        <div class="not-editable-realm-field">
+                            {% trans %}
+                            No account in the imported data matched the email address you've verified with Zulip ({{ email }}).
+                            Select a user account from the data export to associate your email address with, or create a new account if you didn't have an account in the original export.
+                            {% endtrans %}
+                        </div>
+                    </div>
+                    <div class="input-box">
+                        <label for="email" class="inline-block label-title">Select your account</label>
+                        <select id="realm-import-owner" name="email" class="required">
+                            {% for user in users %}
+                                <option value="{{ user.delivery_email }}">
+                                    {{ user.full_name }} ({{user.delivery_email}})
+                                </option>
+                            {% endfor %}
+                        </select>
+                    </div>
+                    <div class="input-box">
+                        <button type="submit" class="register-button">
+                            {{ _("Confirm") }}
+                        </button>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+</div>
+{% endblock %}

zerver/forms.py

@@ -318,6 +318,10 @@ class HomepageForm(forms.Form):
         return email
 
 
+class ImportRealmOwnerSelectionForm(forms.Form):
+    email = forms.EmailField(validators=[email_not_system_bot])
+
+
 class RealmCreationForm(RealmDetailsForm):
     # This form determines whether users can create a new realm.
     email = forms.EmailField(validators=[email_not_system_bot, email_is_not_disposable])

zerver/views/registration.py

@@ -18,10 +18,12 @@ from django.shortcuts import redirect, render
 from django.template.response import TemplateResponse
 from django.urls import reverse
 from django.utils.translation import get_language
+from django.utils.translation import gettext as _
 from django.views.defaults import server_error
 from django_auth_ldap.backend import LDAPBackend, _LDAPUser
 from pydantic import Json, NonNegativeInt, StringConstraints
 
+from confirmation import settings as confirmation_settings
 from confirmation.models import (
     Confirmation,
     ConfirmationKeyError,
@@ -49,12 +51,13 @@ from zerver.decorator import add_google_analytics, do_login, require_post
 from zerver.forms import (
     FindMyTeamForm,
     HomepageForm,
+    ImportRealmOwnerSelectionForm,
     RealmCreationForm,
     RealmRedirectForm,
     RegistrationForm,
 )
 from zerver.lib.email_validation import email_allowed_for_realm, validate_email_not_already_in_realm
-from zerver.lib.exceptions import RateLimitedError
+from zerver.lib.exceptions import JsonableError, RateLimitedError
 from zerver.lib.i18n import (
     get_browser_language_code,
     get_default_language_for_new_user,
@@ -105,6 +108,7 @@ from zerver.views.auth import (
     create_preregistration_user,
     finish_desktop_flow,
     finish_mobile_flow,
+    get_safe_redirect_to,
     redirect_and_log_into_subdomain,
     redirect_to_deactivation_notice,
 )
@@ -877,6 +881,66 @@ def redirect_to_email_login_url(email: str) -> HttpResponseRedirect:
     return HttpResponseRedirect(redirect_url)
 
 
+@transaction.atomic(durable=True)
+def realm_import_post_process(
+    request: HttpRequest,
+    confirmation_key: str,
+) -> HttpResponse:
+    try:
+        preregistration_realm = get_object_from_key(
+            confirmation_key,
+            [Confirmation.REALM_CREATION],
+            mark_object_used=False,
+            allow_used=True,
+        )
+    except ConfirmationKeyError as exception:
+        return render_confirmation_key_error(request, exception)
+
+    assert isinstance(preregistration_realm, PreregistrationRealm)
+    try:
+        realm = Realm.objects.get(string_id=preregistration_realm.string_id)
+    except Realm.DoesNotExist:
+        # If we cannot find the realm, likely means there was something
+        # wrong with the import process. Revoke the confirmation key to
+        # force user to restart the process.
+        preregistration_realm.status = confirmation_settings.STATUS_REVOKED
+        preregistration_realm.save(update_fields=["status"])
+
+        return render_confirmation_key_error(
+            request, ConfirmationKeyError(ConfirmationKeyError.EXPIRED)
+        )
+
+    if not preregistration_realm.data_import_metadata["no_user_matching_email"]:
+        return HttpResponseRedirect(get_safe_redirect_to(reverse("login"), realm.url))
+
+    if request.method == "POST":
+        form = ImportRealmOwnerSelectionForm(request.POST)
+        if form.is_valid():
+            email = form.cleaned_data["email"]
+            user = get_user_by_delivery_email(email, realm)
+            user.delivery_email = preregistration_realm.email
+            user.role = UserProfile.ROLE_REALM_OWNER
+            user.save(update_fields=["delivery_email", "role"])
+            preregistration_realm.status = confirmation_settings.STATUS_USED
+            preregistration_realm.created_realm = realm
+            preregistration_realm.data_import_metadata["no_user_matching_email"] = False
+            preregistration_realm.save()
+            return HttpResponseRedirect(get_safe_redirect_to(reverse("login"), realm.url))
+
+    users = UserProfile.objects.filter(realm=realm, is_bot=False)
+    context = {
+        "users": users,
+        "email": preregistration_realm.email,
+        "key": confirmation_key,
+    }
+
+    return TemplateResponse(
+        request,
+        "zerver/realm_import_post_process.html",
+        context,
+    )
+
+
 @add_google_analytics
 def create_realm(request: HttpRequest, creation_key: str | None = None) -> HttpResponse:
     try:

zproject/urls.py

@@ -143,6 +143,7 @@ from zerver.views.registration import (
     find_account,
     get_prereg_key_and_redirect,
     new_realm_send_confirm,
+    realm_import_post_process,
     realm_redirect,
     realm_register,
     signup_send_confirm,
@@ -593,6 +594,11 @@ i18n_urls = [
     ),
     path("accounts/register/", accounts_register, name="accounts_register"),
     path("realm/register/", realm_register, name="realm_register"),
+    path(
+        "realm/import/post_process/<confirmation_key>",
+        realm_import_post_process,
+        name="realm_import_post_process",
+    ),
     path(
         "accounts/do_confirm/<confirmation_key>",
         get_prereg_key_and_redirect,