feat(backend): add sending login credentials email (#64)

* feat(backend): add sending login credentials email

* feat(backend): add retry policy on sending emails

backend/aaiss_backend/settings.py

@@ -191,4 +191,6 @@
 PAYWALL = env.str("PAYWALL", "ZIFY")
 
 #ZIFY
-ZIFY_AUTH = env.str("ZIFY_AUTH", "")
+ZIFY_AUTH = env.str("ZIFY_AUTH", "")
+
+SKYROOM_URL = env.str("SKYROOM_URL", "https://www.skyroom.online/ch/aut_ceit_ssc/aaiss")

backend/backend_api/admin.py

@@ -1,6 +1,8 @@
 from django import forms
 from django.contrib import admin
+from django.template.loader import render_to_string
 
+from aaiss_backend.settings import SKYROOM_URL
 from backend_api import models
 from backend_api.email import MailerThread
 from backend_api.models import Discount, Presentation, PresentationParticipation, WorkshopRegistration
@@ -37,52 +39,6 @@ class UserAdmin(admin.ModelAdmin):
     list_display = ('account',)
 
 
-class MailerForm(forms.ModelForm):
-    HTML_body = forms.CharField(widget=forms.Textarea)
-
-    class Meta:
-        model = models.Mailer
-        fields = '__all__'
-
-
-class MailerAdmin(admin.ModelAdmin):
-    model = models.Mailer
-    form = MailerForm
-
-    def execute_mailer(self, request, obj):
-        for mailer in obj:
-            if mailer.target_mode == 1:
-                targets = models.User.objects.all()
-                mails = []
-                for target in targets:
-                    mails.append(target.account.email)
-                MailerThread(mailer.subject, mails, mailer.HTML_body).start()
-            elif mailer.target_mode == 2:
-                mails = []
-                for workshop in mailer.workshop_selection.all():
-                    for user in models.User.objects.all():
-                        if workshop in user.registered_workshops.all():
-                            if __name__ == '__main__':
-                                mails.append(user.account.email)
-                MailerThread(mailer.subject, mails, mailer.HTML_body).start()
-            elif mailer.target_mode == 3:
-                mails = []
-                for user in models.User.objects.all():
-                    if user.registered_for_presentations:
-                        mails.append(user.account.email)
-                MailerThread(mailer.subject, mails, mailer.HTML_body).start()
-            elif mailer.target_mode == 4:
-                targets = mailer.user_selection.all()
-                mails = []
-                for target in targets:
-                    mails.append(target.account.email)
-                MailerThread(mailer.subject, mails, mailer.HTML_body).start()
-
-    execute_mailer.short_description = 'Send selected mails'
-    execute_mailer.allow_tags = True
-    actions = ['execute_mailer']
-
-
 class DiscountAdmin(admin.ModelAdmin):
     list_display = ('__str__', 'is_active', 'discount_percent', 'capacity', 'remaining_capacity', 'expiration_date')
     readonly_fields = ('participants',)
@@ -113,7 +69,7 @@ class Meta:
 class PresentationAdmin(admin.ModelAdmin):
     list_display = ('__str__', 'level', 'no_of_participants', 'year')
     readonly_fields = ('participants',)
-    actions = ['export_login_credentials']
+    actions = ['export_login_credentials', 'send_registration_emails']
 
     class Meta:
         model = Presentation
@@ -123,18 +79,34 @@ class Meta:
     def export_login_credentials(self, request, obj):
         user_credentials: list[SkyroomCredentials] = []
         for presentation in obj:
-            for presentation_registration in presentation.presentationparticipation_set.filter(
+            for registration in presentation.presentationparticipation_set.filter(
                     status=PresentationParticipation.StatusChoices.PURCHASED):
                 user_credentials.append(
-                    SkyroomCredentials(presentation_registration.username, presentation_registration.password,
-                                       presentation_registration.user.account.email))
+                    SkyroomCredentials(registration.username, registration.password,
+                                       registration.user.account.email))
         return convert_credentials_to_csv_response(user_credentials)
 
+    @admin.action(description='Send registration emails')
+    def send_registration_emails(self, request, obj):
+        for presentation in obj:
+            for registration in presentation.presentationparticipation_set.filter(
+                    status=PresentationParticipation.StatusChoices.PURCHASED):
+                MailerThread(f"AAISS login credentials for {presentation.name}",
+                             [registration.user.account.email],
+                             render_to_string('login_credentials.html',
+                                              {
+                                                  'username': registration.username,
+                                                  'password': registration.password,
+                                                  'meeting_url': SKYROOM_URL,
+                                                  'meeting_type': 'presentation',
+                                                  'meeting_title': presentation.name,
+                                              })).start()
+
 
 class WorkshopAdmin(admin.ModelAdmin):
     list_display = ('__str__', 'capacity', 'cost', 'has_project', 'level', 'no_of_participants', 'year')
     readonly_fields = ('participants',)
-    actions = ['export_login_credentials']
+    actions = ['export_login_credentials', 'send_registration_emails']
 
     class Meta:
         model = models.Workshop
@@ -144,13 +116,29 @@ class Meta:
     def export_login_credentials(self, request, obj):
         user_credentials: list[SkyroomCredentials] = []
         for workshop in obj:
-            for workshop_registration in workshop.workshopregistration_set.filter(
+            for registration in workshop.workshopregistration_set.filter(
                     status=WorkshopRegistration.StatusChoices.PURCHASED):
                 user_credentials.append(
-                    SkyroomCredentials(workshop_registration.username, workshop_registration.password,
-                                       workshop_registration.user.account.email))
+                    SkyroomCredentials(registration.username, registration.password,
+                                       registration.user.account.email))
         return convert_credentials_to_csv_response(user_credentials)
 
+    @admin.action(description='Send registration emails')
+    def send_registration_emails(self, request, obj):
+        for workshop in obj:
+            for registration in workshop.workshopregistration_set.filter(
+                    status=WorkshopRegistration.StatusChoices.PURCHASED):
+                MailerThread(f"AAISS login credentials for {workshop.name}",
+                             [registration.user.account.email],
+                             render_to_string('login_credentials.html',
+                                              {
+                                                  'username': registration.username,
+                                                  'password': registration.password,
+                                                  'meeting_url': SKYROOM_URL,
+                                                  'meeting_type': 'workshop',
+                                                  'meeting_title': workshop.name,
+                                              })).start()
+
 
 class MiscAdmin(admin.ModelAdmin):
     list_display = ('__str__', 'year')
@@ -163,7 +151,6 @@ class Meta:
 admin.site.register(models.Teacher, TeacherAdmin)
 admin.site.register(models.Presenter, PresenterAdmin)
 admin.site.register(models.User, UserAdmin)
-admin.site.register(models.Mailer, MailerAdmin)
 admin.site.register(models.Discount, DiscountAdmin)
 admin.site.register(models.Payment, PaymentAdmin)
 admin.site.register(models.WorkshopRegistration)

backend/backend_api/email.py

@@ -1,4 +1,5 @@
 import threading
+from time import sleep
 
 from django.conf import settings
 from django.core.mail import EmailMessage
@@ -8,6 +9,9 @@
 
 
 class MailerThread(threading.Thread):
+    _MAXIMUM_RETRIES = 5
+    _SLEEP_INTERVAL_SECONDS = 5
+
     def __init__(self, subject: str, targets: list[str], html_body: str):
         self.subject = subject
         self.targets = targets
@@ -28,7 +32,17 @@ def run(self):
         )
         email.content_subtype = "html"
         if ENABLE_SENDING_EMAIL:
-            email.send(fail_silently=False)
+            has_send = False
+            for i in range(self._MAXIMUM_RETRIES):
+                try:
+                    email.send(fail_silently=True)
+                    has_send = True
+                    break
+                except Exception as e:
+                    print(f"Exception raised while sending email: {e}")
+                    sleep(self._SLEEP_INTERVAL_SECONDS)
+            if not has_send:
+                print(f"Failed to send email to {self.targets} after {self._MAXIMUM_RETRIES} retries")
         else:
             print(f"Sent the following email (change ENABLE_SENDING_EMAIL to True to actually send the email):")
             print(f"To: {email.bcc}\nSubject: {email.subject}\n\nBody: {email.body}\n\n")

backend/backend_api/models.py

@@ -235,7 +235,6 @@ def __str__(self):
         name = ""
         for presenter in self.presenters.all():
             name += presenter.name + " "
-        print(name)
         return f"{name}: {self.name}"
 
 

backend/templates/html/login_credentials.html

@@ -0,0 +1,17 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <title>AAISS 2023 Login Credentials</title>
+</head>
+<body>
+<div>You've registered to <b>{{ meeting_title }}</b>, to enter the {{ meeting_type }} use the following credentials:
+</div>
+
+<br>
+<a href="{{ meeting_url }}">Meeting link</a>
+<br>
+<div>Username: <b>{{ username }}</b></div>
+<div>Password: <b>{{ password }}</b></div>
+</body>
+</html>