From dd87eb77f361aef78a3588cb5609705a1e105591 Mon Sep 17 00:00:00 2001
From: std-odoo <std@odoo.com>
Date: Fri, 13 May 2022 05:41:34 +0000
Subject: [PATCH] [FIX] google_gmail, fetchmail_gmail: use Odoo endpoint for
 authentication

Purpose
=======
The flow where we copy / paste the authorization code will be
depreciated. Because of that, we know use the newest authentication
system which use redirect URI.

Technical
=========
Now, the user is redirected to an Odoo endpoint "google_gmail/confirm"
and the access token / refresh token are automatically fetched.

Documentation
https://developers.google.com/identity/protocols/oauth2/native-app

Task-2852560

closes odoo/odoo#94476

X-original-commit: 69bd9bc6b36fdd55e8e859667bcddddad6db7d06
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>
---
 .../fetchmail_gmail/i18n/fetchmail_gmail.pot  |  32 +++-
 .../views/fetchmail_server_views.xml          |  36 +++--
 addons/google_gmail/__init__.py               |   1 +
 addons/google_gmail/controllers/__init__.py   |   4 +
 addons/google_gmail/controllers/main.py       |  76 +++++++++
 addons/google_gmail/i18n/google_gmail.pot     |  57 ++++++-
 .../google_gmail/models/google_gmail_mixin.py | 151 ++++++++++++++----
 .../views/ir_mail_server_views.xml            |  35 ++--
 8 files changed, 326 insertions(+), 66 deletions(-)
 create mode 100644 addons/google_gmail/controllers/__init__.py
 create mode 100644 addons/google_gmail/controllers/main.py

diff --git a/addons/fetchmail_gmail/i18n/fetchmail_gmail.pot b/addons/fetchmail_gmail/i18n/fetchmail_gmail.pot
index 55c778ec99a..e4f1f7af6a3 100644
--- a/addons/fetchmail_gmail/i18n/fetchmail_gmail.pot
+++ b/addons/fetchmail_gmail/i18n/fetchmail_gmail.pot
@@ -15,6 +15,28 @@ msgstr ""
 "Content-Transfer-Encoding: \n"
 "Plural-Forms: \n"
 
+#. module: fetchmail_gmail
+#: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
+msgid ""
+"<i class=\"fa fa-arrow-right\"/>\n"
+"                        Connect your Gmail account"
+msgstr ""
+
+#. module: fetchmail_gmail
+#: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
+msgid ""
+"<i class=\"fa fa-cog\"/>\n"
+"                        Edit Settings"
+msgstr ""
+
+#. module: fetchmail_gmail
+#: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
+msgid ""
+"<span attrs=\"{'invisible': ['|', ('server_type', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}\" class=\"badge badge-success\">\n"
+"                        Gmail Token Valid\n"
+"                    </span>"
+msgstr ""
+
 #. module: fetchmail_gmail
 #: model:ir.model.fields,field_description:fetchmail_gmail.field_fetchmail_server__google_gmail_access_token
 msgid "Access Token"
@@ -27,15 +49,9 @@ msgstr ""
 
 #. module: fetchmail_gmail
 #: model:ir.model.fields,field_description:fetchmail_gmail.field_fetchmail_server__google_gmail_authorization_code
-#: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
 msgid "Authorization Code"
 msgstr ""
 
-#. module: fetchmail_gmail
-#: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
-msgid "Get an Authorization Code"
-msgstr ""
-
 #. module: fetchmail_gmail
 #: model:ir.model.fields.selection,name:fetchmail_gmail.selection__fetchmail_server__server_type__gmail
 msgid "Gmail OAuth Authentication"
@@ -58,7 +74,9 @@ msgstr ""
 
 #. module: fetchmail_gmail
 #: model_terms:ir.ui.view,arch_db:fetchmail_gmail.fetchmail_server_view_form
-msgid "Setup your Gmail API credentials to link a Gmail account."
+msgid ""
+"Setup your Gmail API credentials in the general settings to link a Gmail "
+"account."
 msgstr ""
 
 #. module: fetchmail_gmail
diff --git a/addons/fetchmail_gmail/views/fetchmail_server_views.xml b/addons/fetchmail_gmail/views/fetchmail_server_views.xml
index 6bbce61d229..b72e3ed1c87 100644
--- a/addons/fetchmail_gmail/views/fetchmail_server_views.xml
+++ b/addons/fetchmail_gmail/views/fetchmail_server_views.xml
@@ -7,18 +7,30 @@
         <field name="inherit_id" ref="fetchmail.view_email_server_form"/>
         <field name="arch" type="xml">
             <field name="user" position="after">
-                <field string="Authorization Code" name="google_gmail_authorization_code" password="True"
-                    attrs="{'required': [('server_type', '=', 'gmail')], 'invisible': [('server_type', '!=', 'gmail')], 'readonly': [('state', '=', 'done')]}"
-                    style="word-break: break-word;"/>
-                <field name="google_gmail_uri"
-                    class="fa fa-arrow-right oe_edit_only"
-                    widget="url"
-                    text=" Get an Authorization Code"
-                    attrs="{'invisible': ['|', ('server_type', '!=', 'gmail'), ('google_gmail_uri', '=', False)]}"
-                    nolabel="1"/>
-                <div class="alert alert-warning" role="alert"
-                    attrs="{'invisible': ['|', ('server_type', '!=', 'gmail'), ('google_gmail_uri', '!=', False)]}">
-                    Setup your Gmail API credentials to link a Gmail account.
+                <field name="google_gmail_uri" invisible="1"/>
+                <field name="google_gmail_refresh_token" invisible="1"/>
+                <div></div>
+                <div attrs="{'invisible': [('server_type', '!=', 'gmail')]}">
+                    <span attrs="{'invisible': ['|', ('server_type', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}"
+                        class="badge badge-success">
+                        Gmail Token Valid
+                    </span>
+                    <button type="object"
+                        name="open_google_gmail_uri" class="btn-link px-0"
+                        attrs="{'invisible': ['|', '|', ('google_gmail_uri', '=', False), ('server_type', '!=', 'gmail'), ('google_gmail_refresh_token', '!=', False)]}">
+                        <i class="fa fa-arrow-right"/>
+                        Connect your Gmail account
+                    </button>
+                    <button type="object"
+                        name="open_google_gmail_uri" class="btn-link px-0"
+                        attrs="{'invisible': ['|', '|', ('google_gmail_uri', '=', False), ('server_type', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}">
+                        <i class="fa fa-cog"/>
+                        Edit Settings
+                    </button>
+                    <div class="alert alert-warning" role="alert"
+                        attrs="{'invisible': ['|', ('server_type', '!=', 'gmail'), ('google_gmail_uri', '!=', False)]}">
+                        Setup your Gmail API credentials in the general settings to link a Gmail account.
+                    </div>
                 </div>
             </field>
             <field name="password" position="attributes">
diff --git a/addons/google_gmail/__init__.py b/addons/google_gmail/__init__.py
index dc5e6b693d1..7d34c7c054a 100644
--- a/addons/google_gmail/__init__.py
+++ b/addons/google_gmail/__init__.py
@@ -1,4 +1,5 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
+from . import controllers
 from . import models
diff --git a/addons/google_gmail/controllers/__init__.py b/addons/google_gmail/controllers/__init__.py
new file mode 100644
index 00000000000..afcdc91f726
--- /dev/null
+++ b/addons/google_gmail/controllers/__init__.py
@@ -0,0 +1,4 @@
+# -*- coding: utf-8 -*
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+from . import main
diff --git a/addons/google_gmail/controllers/main.py b/addons/google_gmail/controllers/main.py
new file mode 100644
index 00000000000..6eaa217f4b8
--- /dev/null
+++ b/addons/google_gmail/controllers/main.py
@@ -0,0 +1,76 @@
+# -*- coding: utf-8 -*-
+# Part of Odoo. See LICENSE file for full copyright and licensing details.
+
+import json
+import logging
+import werkzeug
+
+from werkzeug.exceptions import Forbidden
+from werkzeug.urls import url_encode
+
+from odoo import _, http
+from odoo.exceptions import UserError
+from odoo.http import request
+from odoo.tools import consteq
+
+_logger = logging.getLogger(__name__)
+
+
+class GoogleGmailController(http.Controller):
+    @http.route('/google_gmail/confirm', type='http', auth='user')
+    def google_gmail_callback(self, code=None, state=None, error=None, **kwargs):
+        """Callback URL during the OAuth process.
+
+        Gmail redirects the user browser to this endpoint with the authorization code.
+        We will fetch the refresh token and the access token thanks to this authorization
+        code and save those values on the given mail server.
+        """
+        if not request.env.user.has_group('base.group_system'):
+            _logger.error('Google Gmail: non-system user trying to link an Gmail account.')
+            raise Forbidden()
+
+        if error:
+            return _('An error occur during the authentication process: %s.', error)
+
+        try:
+            state = json.loads(state)
+            model_name = state['model']
+            rec_id = state['id']
+            csrf_token = state['csrf_token']
+        except Exception:
+            _logger.error('Google Gmail: Wrong state value %r.', state)
+            raise Forbidden()
+
+        model = request.env[model_name]
+
+        if not issubclass(type(model), request.env.registry['google.gmail.mixin']):
+            # The model must inherits from the "google.gmail.mixin" mixin
+            raise Forbidden()
+
+        record = model.browse(rec_id).exists()
+        if not record:
+            raise Forbidden()
+
+        if not csrf_token or not consteq(csrf_token, record._get_gmail_csrf_token()):
+            _logger.error('Google Gmail: Wrong CSRF token during Gmail authentication.')
+            raise Forbidden()
+
+        try:
+            refresh_token, access_token, expiration = record._fetch_gmail_refresh_token(code)
+        except UserError as e:
+            return _('An error occur during the authentication process: %s.', str(e.name))
+
+        record.write({
+            'google_gmail_access_token': access_token,
+            'google_gmail_access_token_expiration': expiration,
+            'google_gmail_authorization_code': code,
+            'google_gmail_refresh_token': refresh_token,
+        })
+
+        url_params = {
+            'id': rec_id,
+            'model': model_name,
+            'view_type': 'form'
+        }
+        url = '/web?#' + url_encode(url_params)
+        return werkzeug.utils.redirect(url, 303)
diff --git a/addons/google_gmail/i18n/google_gmail.pot b/addons/google_gmail/i18n/google_gmail.pot
index 56647d78fad..04225d32656 100644
--- a/addons/google_gmail/i18n/google_gmail.pot
+++ b/addons/google_gmail/i18n/google_gmail.pot
@@ -15,6 +15,28 @@ msgstr ""
 "Content-Transfer-Encoding: \n"
 "Plural-Forms: \n"
 
+#. module: google_gmail
+#: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
+msgid ""
+"<i class=\"fa fa-arrow-right\"/>\n"
+"                        Connect your Gmail account"
+msgstr ""
+
+#. module: google_gmail
+#: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
+msgid ""
+"<i class=\"fa fa-cog\"/>\n"
+"                        Edit Settings"
+msgstr ""
+
+#. module: google_gmail
+#: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
+msgid ""
+"<span attrs=\"{'invisible': ['|', ('smtp_authentication', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}\" class=\"badge badge-success\">\n"
+"                        Gmail Token Valid\n"
+"                    </span>"
+msgstr ""
+
 #. module: google_gmail
 #: model:ir.model.fields,field_description:google_gmail.field_google_gmail_mixin__google_gmail_access_token
 #: model:ir.model.fields,field_description:google_gmail.field_ir_mail_server__google_gmail_access_token
@@ -27,6 +49,19 @@ msgstr ""
 msgid "Access Token Expiration Timestamp"
 msgstr ""
 
+#. module: google_gmail
+#: code:addons/google_gmail/controllers/main.py:0
+#: code:addons/google_gmail/controllers/main.py:0
+#, python-format
+msgid "An error occur during the authentication process: %s."
+msgstr ""
+
+#. module: google_gmail
+#: code:addons/google_gmail/models/google_gmail_mixin.py:0
+#, python-format
+msgid "An error occurred when fetching the access token."
+msgstr ""
+
 #. module: google_gmail
 #: model:ir.model.fields,field_description:google_gmail.field_ir_mail_server__smtp_authentication
 msgid "Authenticate with"
@@ -35,7 +70,6 @@ msgstr ""
 #. module: google_gmail
 #: model:ir.model.fields,field_description:google_gmail.field_google_gmail_mixin__google_gmail_authorization_code
 #: model:ir.model.fields,field_description:google_gmail.field_ir_mail_server__google_gmail_authorization_code
-#: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
 msgid "Authorization Code"
 msgstr ""
 
@@ -54,11 +88,6 @@ msgstr ""
 msgid "Config Settings"
 msgstr ""
 
-#. module: google_gmail
-#: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
-msgid "Get an Authorization Code"
-msgstr ""
-
 #. module: google_gmail
 #: model:ir.model.fields,field_description:google_gmail.field_res_config_settings__google_gmail_client_identifier
 msgid "Gmail Client Id"
@@ -84,6 +113,18 @@ msgstr ""
 msgid "Mail Server"
 msgstr ""
 
+#. module: google_gmail
+#: code:addons/google_gmail/models/google_gmail_mixin.py:0
+#, python-format
+msgid "Only the administrator can link a Gmail mail server."
+msgstr ""
+
+#. module: google_gmail
+#: code:addons/google_gmail/models/google_gmail_mixin.py:0
+#, python-format
+msgid "Please configure your Gmail credentials."
+msgstr ""
+
 #. module: google_gmail
 #: model:ir.model.fields,field_description:google_gmail.field_google_gmail_mixin__google_gmail_refresh_token
 #: model:ir.model.fields,field_description:google_gmail.field_ir_mail_server__google_gmail_refresh_token
@@ -92,7 +133,9 @@ msgstr ""
 
 #. module: google_gmail
 #: model_terms:ir.ui.view,arch_db:google_gmail.ir_mail_server_view_form
-msgid "Setup your Gmail API credentials to link a Gmail account."
+msgid ""
+"Setup your Gmail API credentials in the general settings to link a Gmail "
+"account."
 msgstr ""
 
 #. module: google_gmail
diff --git a/addons/google_gmail/models/google_gmail_mixin.py b/addons/google_gmail/models/google_gmail_mixin.py
index 10e8cd7cd73..1a41e915bf4 100644
--- a/addons/google_gmail/models/google_gmail_mixin.py
+++ b/addons/google_gmail/models/google_gmail_mixin.py
@@ -1,10 +1,15 @@
 # -*- coding: utf-8 -*-
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
+import json
 import logging
 import time
+import requests
 
-from odoo import api, fields, models
+from werkzeug.urls import url_encode, url_join
+
+from odoo import _, api, fields, models, tools
+from odoo.exceptions import AccessError, UserError
 
 _logger = logging.getLogger(__name__)
 
@@ -27,38 +32,107 @@ class GoogleGmailMixin(models.AbstractModel):
         Config = self.env['ir.config_parameter'].sudo()
         google_gmail_client_id = Config.get_param('google_gmail_client_id')
         google_gmail_client_secret = Config.get_param('google_gmail_client_secret')
+        base_url = self.get_base_url()
+
+        redirect_uri = url_join(base_url, '/google_gmail/confirm')
 
         if not google_gmail_client_id or not google_gmail_client_secret:
             self.google_gmail_uri = False
         else:
-            google_gmail_uri = self.env['google.service']._get_google_token_uri('gmail', scope=self._SERVICE_SCOPE)
-            self.google_gmail_uri = google_gmail_uri
+            for record in self:
+                google_gmail_uri = 'https://accounts.google.com/o/oauth2/v2/auth?%s' % url_encode({
+                    'client_id': google_gmail_client_id,
+                    'redirect_uri': redirect_uri,
+                    'response_type': 'code',
+                    'scope': self._SERVICE_SCOPE,
+                    # access_type and prompt needed to get a refresh token
+                    'access_type': 'offline',
+                    'prompt': 'consent',
+                    'state': json.dumps({
+                        'model': record._name,
+                        'id': record.id or False,
+                        'csrf_token': record._get_gmail_csrf_token() if record.id else False,
+                    })
+                })
+                record.google_gmail_uri = google_gmail_uri
 
-    @api.model_create_multi
-    def create(self, vals_list):
-        for values in vals_list:
-            if values.get('google_gmail_authorization_code'):
-                # Generate the refresh token
-                values['google_gmail_refresh_token'] = self.env['google.service'].generate_refresh_token(
-                    'gmail', values['google_gmail_authorization_code'])
-                values['google_gmail_access_token'] = False
-                values['google_gmail_access_token_expiration'] = False
+    def open_google_gmail_uri(self):
+        """Open the URL to accept the Gmail permission.
 
-        return super(GoogleGmailMixin, self).create(vals_list)
+        This is done with an action, so we can force the user the save the form.
+        We need him to save the form so the current mail server record exist in DB, and
+        we can include the record ID in the URL.
+        """
+        self.ensure_one()
 
-    def write(self, values):
-        authorization_code = values.get('google_gmail_authorization_code')
-        if (
-            authorization_code
-            and not all(authorization_code == code for code in self.mapped('google_gmail_authorization_code'))
-        ):
-            # Update the refresh token
-            values['google_gmail_refresh_token'] = self.env['google.service'].generate_refresh_token(
-                'gmail', authorization_code)
-            values['google_gmail_access_token'] = False
-            values['google_gmail_access_token_expiration'] = False
+        if not self.env.user.has_group('base.group_system'):
+            raise AccessError(_('Only the administrator can link a Gmail mail server.'))
 
-        return super(GoogleGmailMixin, self).write(values)
+        if not self.google_gmail_uri:
+            raise UserError(_('Please configure your Gmail credentials.'))
+
+        return {
+            'type': 'ir.actions.act_url',
+            'url': self.google_gmail_uri,
+        }
+
+    def _fetch_gmail_refresh_token(self, authorization_code):
+        """Request the refresh token and the initial access token from the authorization code.
+
+        :return:
+            refresh_token, access_token, access_token_expiration
+        """
+        response = self._fetch_gmail_token('authorization_code', code=authorization_code)
+
+        return (
+            response['refresh_token'],
+            response['access_token'],
+            int(time.time()) + response['expires_in'],
+        )
+
+    def _fetch_gmail_access_token(self, refresh_token):
+        """Refresh the access token thanks to the refresh token.
+
+        :return:
+            access_token, access_token_expiration
+        """
+        response = self._fetch_gmail_token('refresh_token', refresh_token=refresh_token)
+
+        return (
+            response['access_token'],
+            int(time.time()) + response['expires_in'],
+        )
+
+    def _fetch_gmail_token(self, grant_type, **values):
+        """Generic method to request an access token or a refresh token.
+
+        Return the JSON response of the GMail API and manage the errors which can occur.
+
+        :param grant_type: Depends the action we want to do (refresh_token or authorization_code)
+        :param values: Additional parameters that will be given to the GMail endpoint
+        """
+        Config = self.env['ir.config_parameter'].sudo()
+        google_gmail_client_id = Config.get_param('google_gmail_client_id')
+        google_gmail_client_secret = Config.get_param('google_gmail_client_secret')
+        base_url = self.get_base_url()
+        redirect_uri = url_join(base_url, '/google_gmail/confirm')
+
+        response = requests.post(
+            'https://oauth2.googleapis.com/token',
+            data={
+                'client_id': google_gmail_client_id,
+                'client_secret': google_gmail_client_secret,
+                'grant_type': grant_type,
+                'redirect_uri': redirect_uri,
+                **values,
+            },
+            timeout=5,
+        )
+
+        if not response.ok:
+            raise UserError(_('An error occurred when fetching the access token.'))
+
+        return response.json()
 
     def _generate_oauth2_string(self, user, refresh_token):
         """Generate a OAuth2 string which can be used for authentication.
@@ -73,14 +147,33 @@ class GoogleGmailMixin(models.AbstractModel):
         if not self.google_gmail_access_token \
            or not self.google_gmail_access_token_expiration \
            or self.google_gmail_access_token_expiration < now_timestamp:
-            self.google_gmail_access_token, expires_in = self.env['google.service']._get_access_token(
-                refresh_token, 'gmail', self._SERVICE_SCOPE)
-            self.google_gmail_access_token_expiration = now_timestamp + expires_in
 
-            _logger.info('Google Gmail: fetch new access token. Expire in %i minutes', expires_in // 60)
+            access_token, expiration = self._fetch_gmail_access_token(self.google_gmail_refresh_token)
+
+            self.write({
+                'google_gmail_access_token': access_token,
+                'google_gmail_access_token_expiration': expiration,
+            })
+
+            _logger.info(
+                'Google Gmail: fetch new access token. Expires in %i minutes',
+                (self.google_gmail_access_token_expiration - now_timestamp) // 60)
         else:
             _logger.info(
                 'Google Gmail: reuse existing access token. Expire in %i minutes',
                 (self.google_gmail_access_token_expiration - now_timestamp) // 60)
 
         return 'user=%s\1auth=Bearer %s\1\1' % (user, self.google_gmail_access_token)
+
+    def _get_gmail_csrf_token(self):
+        """Generate a CSRF token that will be verified in `google_gmail_callback`.
+
+        This will prevent a malicious person to make an admin user disconnect the mail servers.
+        """
+        self.ensure_one()
+        _logger.info('Google Gmail: generate CSRF token for %s #%i', self._name, self.id)
+        return tools.misc.hmac(
+            env=self.env(su=True),
+            scope='google_gmail_oauth',
+            message=(self._name, self.id),
+        )
diff --git a/addons/google_gmail/views/ir_mail_server_views.xml b/addons/google_gmail/views/ir_mail_server_views.xml
index d8755f71386..76bb5a40123 100644
--- a/addons/google_gmail/views/ir_mail_server_views.xml
+++ b/addons/google_gmail/views/ir_mail_server_views.xml
@@ -6,17 +6,30 @@
         <field name="inherit_id" ref="base.ir_mail_server_form"/>
         <field name="arch" type="xml">
             <field name="smtp_user" position="after">
-                <field string="Authorization Code" name="google_gmail_authorization_code" password="True"
-                    attrs="{'required': [('smtp_authentication', '=', 'gmail')], 'invisible': [('smtp_authentication', '!=', 'gmail')]}"/>
-                <field name="google_gmail_uri"
-                    class="fa fa-arrow-right oe_edit_only"
-                    widget="url"
-                    text=" Get an Authorization Code"
-                    attrs="{'invisible': ['|', ('smtp_authentication', '!=', 'gmail'), ('google_gmail_uri', '=', False)]}"
-                    nolabel="1"/>
-                <div class="alert alert-warning" role="alert"
-                    attrs="{'invisible': ['|', ('smtp_authentication', '!=', 'gmail'), ('google_gmail_uri', '!=', False)]}">
-                    Setup your Gmail API credentials to link a Gmail account.
+                <field name="google_gmail_uri" invisible="1"/>
+                <field name="google_gmail_refresh_token" invisible="1"/>
+                <div></div>
+                <div attrs="{'invisible': [('smtp_authentication', '!=', 'gmail')]}">
+                    <span attrs="{'invisible': ['|', ('smtp_authentication', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}"
+                        class="badge badge-success">
+                        Gmail Token Valid
+                    </span>
+                    <button type="object"
+                        name="open_google_gmail_uri" class="btn-link px-0"
+                        attrs="{'invisible': ['|', '|', ('google_gmail_uri', '=', False), ('smtp_authentication', '!=', 'gmail'), ('google_gmail_refresh_token', '!=', False)]}">
+                        <i class="fa fa-arrow-right"/>
+                        Connect your Gmail account
+                    </button>
+                    <button type="object"
+                        name="open_google_gmail_uri" class="btn-link px-0"
+                        attrs="{'invisible': ['|', '|', ('google_gmail_uri', '=', False), ('smtp_authentication', '!=', 'gmail'), ('google_gmail_refresh_token', '=', False)]}">
+                        <i class="fa fa-cog"/>
+                        Edit Settings
+                    </button>
+                    <div class="alert alert-warning" role="alert"
+                        attrs="{'invisible': ['|', ('smtp_authentication', '!=', 'gmail'), ('google_gmail_uri', '!=', False)]}">
+                        Setup your Gmail API credentials in the general settings to link a Gmail account.
+                    </div>
                 </div>
             </field>
             <field name="smtp_user" position="attributes">