privacy_consent: Separate automated emails send process

Before OCA#29 there was a race condition where an email could be sent while the same transaction that created the `privacy.consent` record still wasn't committed, producing a 404 error if the user clicked on "Accept" or "Reject" before all mails were sent.

To avoid that, a raw `cr.commit()` was issued, but this produced another situation where the user had to wait until the full email queue is cleared to get his page loaded. It wasn't an error, but a long queue meant several minutes waiting, and it's ulikely that an average human is so patient.

So, here's the final fix (I hope!). The main problem was that I was looking in the wrong place to send the email. It turns out that the `self.post_message_with_template()` method is absolutely helpless in the case at hand, where these criteria must be met:

* E-mail must be enqueued, no matter if there are less or more than 50 consents to send.
* The template must be processed per record.
* In an ideal world, a `cr.commit()` must be issued after each sent mail.

The metod that was being used:

* Didn't allow to use `auto_commit` mode.
* Only allowed to render the template per record if called with `composition_mode="mass_mail"`.
* Only allowed to enqueue emails if called with `composition_mode="mass_post"`.

Obviously, I cannot set 2 different values for `composition_mode`, so a different strategy had to be used.

I discovered that the `mail.template` model has a helpful method called `send_mail()` that, by default:

* Renders the template per record
* Enqueues the email
* The email queue is cleared in `auto_commit=True` mode.

So, from now on, problems are gone:

* The user click, or the cron run, will just generate the missing `privacy.consent` records and enqueue mails for them.
* The mail queue manager will send them later, in `auto_commit` mode.
* After sending the e-mail, this module will set the `privacy.consent` record as `sent`.
* Thanks to *not* sending the email, the process the user faces when he hits the "generate" button is faster.
* Instructions in the README and text in the "generate" button are updated to reflect this new behavior.
* Thanks to the `auto_commit` feature, if Odoo is rebooted in the middle of a mail queue clearance, the records that were sent remain properly marked as sent, and the missing mails will be sent after the next boot.
* No hardcoded commits.
* No locked transactions.
* BTW I discovered that 2 different emails were created when creating a new consent. I started using `mail_create_nolog=True` to avoid that problem and only log a single creation message.

Note to self: never use again `post_message_with_template()`.

privacy_consent/README.rst

@@ -106,8 +106,8 @@ New options for data processing activities:
    * If you chose *Manual* mode, all missing consent request are created as
      drafts, and nothing else is done now.
 
-   * If you chose *Automatic* mode, also those requests are sent to subjects
-     and set as *Sent*.
+   * If you chose *Automatic* mode, also those request e-mails are enqueued
+     and, when the mail queue is cleared, they will be set as *Sent*.
 
 #. You will be presented with the list of just-created consent requests.
    See below.

privacy_consent/data/mail.xml

@@ -7,6 +7,7 @@
 
     <!-- Mail templates -->
     <record id="template_consent" model="mail.template">
+        <field name="auto_delete" eval="False"/>
         <field name="name">Personal data processing consent request</field>
         <field name="subject">Data processing consent request for ${object.activity_id.display_name|safe}</field>
         <field name="model_id" ref="model_privacy_consent"/>

privacy_consent/i18n/es.po

@@ -6,16 +6,16 @@ msgid ""
 msgstr ""
 "Project-Id-Version: Odoo Server 10.0\n"
 "Report-Msgid-Bugs-To: \n"
-"POT-Creation-Date: 2018-07-11 08:38+0000\n"
-"PO-Revision-Date: 2018-07-11 11:07+0200\n"
+"POT-Creation-Date: 2019-05-13 17:04+0000\n"
+"PO-Revision-Date: 2019-05-13 18:08+0100\n"
 "Last-Translator: Jairo Llopis <yajo.sk8@gmail.com>\n"
 "Language-Team: \n"
 "Language: es_ES\n"
 "MIME-Version: 1.0\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Content-Transfer-Encoding: 8bit\n"
 "Plural-Forms: nplurals=2; plural=(n != 1);\n"
-"X-Generator: Poedit 2.0.8\n"
+"X-Generator: Poedit 2.2.1\n"
 
 #. module: privacy_consent
 #: model:mail.template,body_html:privacy_consent.template_consent
@@ -372,6 +372,11 @@ msgstr "Contacto duplicado en esta actividad de tratamiento"
 msgid "Email Templates"
 msgstr "Plantillas de correo electrónico"
 
+#. module: privacy_consent
+#: model:ir.model,name:privacy_consent.model_mail_compose_message
+msgid "Email composition wizard"
+msgstr "Asistente de redacción de correo electrónico"
+
 #. module: privacy_consent
 #: model:ir.model.fields,field_description:privacy_consent.field_privacy_activity_consent_template_id
 msgid "Email template"
@@ -394,20 +399,22 @@ msgid ""
 "Enable if you need to track any kind of consent from the affected subjects"
 msgstr ""
 "Actívelo si necesita registrar cualquier tipo de consentimiento de los "
-"interesados."
+"interesados"
 
 #. module: privacy_consent
 #: model:ir.ui.view,arch_db:privacy_consent.activity_form
-msgid "Generate and send missing consent requests"
-msgstr "Generar y enviar solicitudes de consentimiento faltantes"
+msgid "Generate and enqueue missing consent requests"
+msgstr ""
+"Generar y colocar en la bandeja de salida las solicitudes de consentimiento "
+"que falten"
 
 #. module: privacy_consent
 #: model:ir.ui.view,arch_db:privacy_consent.activity_form
 msgid "Generate missing draft consent requests"
 msgstr "Generar borradores de las solicitudes de consentimiento faltantes"
 
 #. module: privacy_consent
-#: code:addons/privacy_consent/models/privacy_activity.py:142
+#: code:addons/privacy_consent/models/privacy_activity.py:139
 #, python-format
 msgid "Generated consents"
 msgstr "Consentimientos generados"
@@ -623,10 +630,10 @@ msgstr "Gracias por su respuesta."
 
 #. module: privacy_consent
 #: model:ir.ui.view,arch_db:privacy_consent.activity_form
-msgid "This could send many consent emails, are you sure to proceed?"
+msgid "This could enqueue many consent emails, are you sure to proceed?"
 msgstr ""
-"Esto podría enviar muchos correos electrónicos solicitando consentimiento "
-"para el tratamiento de datos, ¿seguro que quiere continuar?"
+"Esto podría poner en la cola muchos correos electrónicos solicitando "
+"consentimiento para el tratamiento de datos, ¿seguro que quiere continuar?"
 
 #. module: privacy_consent
 #: model:ir.actions.server,name:privacy_consent.update_opt_out
@@ -656,6 +663,3 @@ msgstr "Ha <b class=\"text-danger\">rechazado</b> dicho tratamiento."
 #: model:ir.ui.view,arch_db:privacy_consent.form
 msgid "You have <b class=\"text-success\">accepted</b> such processing."
 msgstr "Ha <b class=\"text-success\">aceptado</b> dicho tratamiento."
-
-#~ msgid "Email composition wizard"
-#~ msgstr "Asistente de redacción de correo electrónico"

privacy_consent/i18n/privacy_consent.pot

@@ -6,6 +6,8 @@ msgid ""
 msgstr ""
 "Project-Id-Version: Odoo Server 10.0\n"
 "Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2019-05-13 17:04+0000\n"
+"PO-Revision-Date: 2019-05-13 17:04+0000\n"
 "Last-Translator: <>\n"
 "Language-Team: \n"
 "MIME-Version: 1.0\n"
@@ -237,6 +239,11 @@ msgstr ""
 msgid "Email Templates"
 msgstr ""
 
+#. module: privacy_consent
+#: model:ir.model,name:privacy_consent.model_mail_compose_message
+msgid "Email composition wizard"
+msgstr ""
+
 #. module: privacy_consent
 #: model:ir.model.fields,field_description:privacy_consent.field_privacy_activity_consent_template_id
 msgid "Email template"
@@ -254,7 +261,7 @@ msgstr ""
 
 #. module: privacy_consent
 #: model:ir.ui.view,arch_db:privacy_consent.activity_form
-msgid "Generate and send missing consent requests"
+msgid "Generate and enqueue missing consent requests"
 msgstr ""
 
 #. module: privacy_consent
@@ -263,7 +270,7 @@ msgid "Generate missing draft consent requests"
 msgstr ""
 
 #. module: privacy_consent
-#: code:addons/privacy_consent/models/privacy_activity.py:142
+#: code:addons/privacy_consent/models/privacy_activity.py:139
 #, python-format
 msgid "Generated consents"
 msgstr ""
@@ -452,7 +459,7 @@ msgstr ""
 
 #. module: privacy_consent
 #: model:ir.ui.view,arch_db:privacy_consent.activity_form
-msgid "This could send many consent emails, are you sure to proceed?"
+msgid "This could enqueue many consent emails, are you sure to proceed?"
 msgstr ""
 
 #. module: privacy_consent

privacy_consent/models/privacy_activity.py

@@ -131,9 +131,6 @@ def action_new_consents(self):
                     "accepted": one.default_consent,
                     "activity_id": one.id,
                 })
-        # Avoid race condition where a user could click on accept/reject link
-        # in his email before its consent record is saved to the database
-        consents.env.cr.commit()
         # Send consent request emails for automatic activitys
         consents.action_auto_ask()
         # Redirect user to new consent requests generated

privacy_consent/models/privacy_consent.py

@@ -101,23 +101,10 @@ def _url(self, accept):
 
     def _send_consent_notification(self):
         """Send email notification to subject."""
-        consents_by_template = {}
         for one in self.with_context(tpl_force_default_to=True,
                                      mail_notify_user_signature=False,
                                      mail_auto_subscribe_no_notify=True):
-            # Group consents by template, to send in batch where possible
-            template_id = one.activity_id.consent_template_id.id
-            consents_by_template.setdefault(template_id, one)
-            consents_by_template[template_id] |= one
-        # Send emails
-        for template_id, consents in consents_by_template.items():
-            consents.message_post_with_template(
-                template_id,
-                # This mode always sends email, regardless of partner's
-                # notification preferences; we use it here because it's very
-                # likely that we are asking authorisation to send emails
-                composition_mode="mass_mail",
-            )
+            one.activity_id.consent_template_id.send_mail(one.id)
 
     def _run_action(self):
         """Execute server action defined in data processing activity."""
@@ -135,7 +122,8 @@ def _run_action(self):
     @api.model
     def create(self, vals):
         """Run server action on create."""
-        result = super(PrivacyConsent, self).create(vals)
+        result = super(PrivacyConsent,
+                       self.with_context(mail_create_nolog=True)).create(vals)
         # Sync the default acceptance status
         result.sudo()._run_action()
         return result

privacy_consent/readme/USAGE.rst

@@ -44,8 +44,8 @@ New options for data processing activities:
    * If you chose *Manual* mode, all missing consent request are created as
      drafts, and nothing else is done now.
 
-   * If you chose *Automatic* mode, also those requests are sent to subjects
-     and set as *Sent*.
+   * If you chose *Automatic* mode, also those request e-mails are enqueued
+     and, when the mail queue is cleared, they will be set as *Sent*.
 
 #. You will be presented with the list of just-created consent requests.
    See below.

privacy_consent/static/description/index.html

@@ -456,8 +456,8 @@ <h1><a class="toc-backref" href="#id3">Usage</a></h1>
 <ul class="simple">
 <li>If you chose <em>Manual</em> mode, all missing consent request are created as
 drafts, and nothing else is done now.</li>
-<li>If you chose <em>Automatic</em> mode, also those requests are sent to subjects
-and set as <em>Sent</em>.</li>
+<li>If you chose <em>Automatic</em> mode, also those request e-mails are enqueued
+and, when the mail queue is cleared, they will be set as <em>Sent</em>.</li>
 </ul>
 </li>
 <li><p class="first">You will be presented with the list of just-created consent requests.

privacy_consent/tests/test_consent.py

@@ -17,6 +17,8 @@ def setUp(self):
         self.env = self._oldenv(self.cursor())
         # HACK end
         self.cron = self.env.ref("privacy_consent.cron_auto_consent")
+        self.cron_mail_queue = self.env.ref(
+            "mail.ir_cron_mail_scheduler_action")
         self.update_opt_out = self.env.ref("privacy_consent.update_opt_out")
         self.mt_consent_consent_new = self.env.ref(
             "privacy_consent.mt_consent_consent_new")
@@ -93,11 +95,17 @@ def check_activity_auto_properly_sent(self):
         consents = self.env["privacy.consent"].search([
             ("activity_id", "=", self.activity_auto.id),
         ])
+        # Check pending mails
+        for consent in consents:
+            self.assertEqual(consent.state, "draft")
+            messages = consent.message_ids
+            self.assertEqual(len(messages), 2)
         # Check sent mails
+        self.cron_mail_queue.method_direct_trigger()
         for consent in consents:
             self.assertEqual(consent.state, "sent")
-            messages = consent.mapped("message_ids")
-            self.assertEqual(len(messages), 4)
+            messages = consent.message_ids
+            self.assertEqual(len(messages), 3)
             # 2nd message notifies creation
             self.assertEqual(
                 messages[2].subtype_id,
@@ -167,7 +175,7 @@ def test_generate_manually(self):
         self.assertEqual(consents.mapped("last_metadata"), [False] * 2)
         # Check sent mails
         messages = consents.mapped("message_ids")
-        self.assertEqual(len(messages), 4)
+        self.assertEqual(len(messages), 2)
         subtypes = messages.mapped("subtype_id")
         self.assertTrue(subtypes & self.mt_consent_consent_new)
         self.assertFalse(subtypes & self.mt_consent_acceptance_changed)

privacy_consent/views/privacy_activity.xml

@@ -46,8 +46,8 @@
                                 icon="fa-user-plus"
                                 name="action_new_consents"
                                 type="object"
-                                string="Generate and send missing consent requests"
-                                confirm="This could send many consent emails, are you sure to proceed?"
+                                string="Generate and enqueue missing consent requests"
+                                confirm="This could enqueue many consent emails, are you sure to proceed?"
                             />
                         </div>
                     </group>