feat: SMTP as a fallback function when Sendgrid quota exceeds limit (f…

…ossasia#5981) Modified arguments placement Corrected quota info Sent email and handled error Cease email service if SMTP not configured fix travis divided into two tasks changed logger message and smtp fallback
iamareebjamal · Aug 2, 2019 · 1fc75b0 · 1fc75b0
1 parent ff81819
commit 1fc75b0
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Showing 2 changed files with 91 additions and 65 deletions.
diff --git a/app/api/helpers/mail.py b/app/api/helpers/mail.py
@@ -1,4 +1,5 @@
 import base64
+import logging
 from datetime import datetime
 
 from flask import current_app
@@ -16,10 +17,28 @@
 from app.models.user import User
 
 
+def check_smtp_config(smtp_encryption):
+    """
+    Checks config of SMTP
+    """
+    config = {
+                'host': get_settings()['smtp_host'],
+                'username': get_settings()['smtp_username'],
+                'password': get_settings()['smtp_password'],
+                'encryption': smtp_encryption,
+                'port': get_settings()['smtp_port'],
+    }
+    for field in config:
+        if field is None:
+            return False
+    return True
+
+
 def send_email(to, action, subject, html, attachments=None):
     """
     Sends email and records it in DB
     """
+    from .tasks import send_email_task_sendgrid, send_email_task_smtp
     if not string_empty(to):
         email_service = get_settings()['email_service']
         email_from_name = get_settings()['email_from_name']
@@ -36,40 +55,41 @@ def send_email(to, action, subject, html, attachments=None):
         }
 
         if not current_app.config['TESTING']:
-            if email_service == 'smtp':
-                smtp_encryption = get_settings()['smtp_encryption']
-                if smtp_encryption == 'tls':
-                    smtp_encryption = 'required'
-                elif smtp_encryption == 'ssl':
-                    smtp_encryption = 'ssl'
-                elif smtp_encryption == 'tls_optional':
-                    smtp_encryption = 'optional'
-                else:
-                    smtp_encryption = 'none'
-
-                config = {
-                    'host': get_settings()['smtp_host'],
-                    'username': get_settings()['smtp_username'],
-                    'password': get_settings()['smtp_password'],
-                    'encryption': smtp_encryption,
-                    'port': get_settings()['smtp_port'],
-                }
-
-                from .tasks import send_mail_via_smtp_task
-                send_mail_via_smtp_task.delay(config, payload)
+            smtp_encryption = get_settings()['smtp_encryption']
+            if smtp_encryption == 'tls':
+                smtp_encryption = 'required'
+            elif smtp_encryption == 'ssl':
+                smtp_encryption = 'ssl'
+            elif smtp_encryption == 'tls_optional':
+                smtp_encryption = 'optional'
             else:
-                payload['fromname'] = email_from_name
-                key = get_settings()['sendgrid_key']
-                if not key:
-                    print('Sendgrid key not defined')
-                    return
-                headers = {
-                    "Authorization": ("Bearer " + key),
-                    "Content-Type": "application/json"
-                }
-                from .tasks import send_email_task
-                send_email_task.delay(payload, headers)
+                smtp_encryption = 'none'
+
+            smtp_config = {
+                'host': get_settings()['smtp_host'],
+                'username': get_settings()['smtp_username'],
+                'password': get_settings()['smtp_password'],
+                'encryption': smtp_encryption,
+                'port': get_settings()['smtp_port'],
+            }
+            smtp_status = check_smtp_config(smtp_encryption)
+            if smtp_status:
+                if email_service == 'smtp':
+                    send_email_task_smtp.delay(payload=payload, headers=None, smtp_config=smtp_config)
+                else:
+                    key = get_settings().get('sendgrid_key')
+                    if key:
+                        headers = {
+                            "Authorization": ("Bearer " + key),
+                            "Content-Type": "application/json"
+                        }
+                        payload['fromname'] = email_from_name
+                        send_email_task_sendgrid.delay(payload=payload, headers=headers, smtp_config=smtp_config)
+                    else:
+                        logging.exception('SMTP & sendgrid have not been configured properly')
 
+            else:
+                logging.exception('SMTP is not configured properly. Cannot send email.')
         # record_mail(to, action, subject, html)
         mail = Mail(
             recipient=to, action=action, subject=subject,

diff --git a/app/api/helpers/tasks.py b/app/api/helpers/tasks.py
@@ -18,6 +18,7 @@
 from app.models.session import Session
 from app.models.speaker import Speaker
 
+
 """
 Define all API v2 celery tasks here
 This is done to resolve circular imports
@@ -51,58 +52,63 @@
 celery = make_celery()
 
 
-@celery.task(name='send.email.post')
-def send_email_task(payload, headers):
-    message = Mail(from_email=payload['from'],
-                   to_emails=payload['to'],
-                   subject=payload['subject'],
-                   html_content=payload["html"])
-    if payload['attachments'] is not None:
-        for attachment in payload['attachments']:
-            with open(attachment, 'rb') as f:
-                file_data = f.read()
-                f.close()
-            encoded = base64.b64encode(file_data).decode()
-            attachment = Attachment()
-            attachment.file_content = FileContent(encoded)
-            attachment.file_type = FileType('application/pdf')
-            attachment.file_name = FileName(payload['to'])
-            attachment.disposition = Disposition('attachment')
-            message.add_attachment(attachment)
-    sendgrid_client = SendGridAPIClient(get_settings()['sendgrid_key'])
-    logging.info('Sending an email regarding {} on behalf of {}'.format(payload["subject"], payload["from"]))
+@celery.task(name='send.email.post.sendgrid')
+def send_email_task_sendgrid(payload, headers, smtp_config):
     try:
+        message = Mail(from_email=payload['from'],
+                       to_emails=payload['to'],
+                       subject=payload['subject'],
+                       html_content=payload["html"])
+        if payload['attachments'] is not None:
+            for attachment in payload['attachments']:
+                with open(attachment, 'rb') as f:
+                    file_data = f.read()
+                    f.close()
+                encoded = base64.b64encode(file_data).decode()
+                attachment = Attachment()
+                attachment.file_content = FileContent(encoded)
+                attachment.file_type = FileType('application/pdf')
+                attachment.file_name = FileName(payload['to'])
+                attachment.disposition = Disposition('attachment')
+                message.add_attachment(attachment)
+        sendgrid_client = SendGridAPIClient(get_settings()['sendgrid_key'])
+        logging.info('Sending an email regarding {} on behalf of {}'.format(payload["subject"], payload["from"]))
         sendgrid_client.send(message)
         logging.info('Email sent successfully')
-    except Exception:
-        logging.exception('Error occured while sending the email')
+    except urllib.error.HTTPError as e:
+        if e.code == 429:
+            logging.warning("Sendgrid quota has exceeded")
+            send_email_task_smtp.delay(payload=payload, headers=None, smtp_config=smtp_config)
+        else:
+            logging.exception("The following error has occurred with sendgrid-{}".format(str(e)))
 
 
 @celery.task(name='send.email.post.smtp')
-def send_mail_via_smtp_task(config, payload):
+def send_email_task_smtp(payload, smtp_config, headers=None):
     mailer_config = {
-        'transport': {
-            'use': 'smtp',
-            'host': config['host'],
-            'username': config['username'],
-            'password': config['password'],
-            'tls': config['encryption'],
-            'port': config['port']
+            'transport': {
+                'use': 'smtp',
+                'host': smtp_config['host'],
+                'username': smtp_config['username'],
+                'password': smtp_config['password'],
+                'tls': smtp_config['encryption'],
+                'port': smtp_config['port']
+            }
         }
-    }
 
     mailer = Mailer(mailer_config)
     mailer.start()
     message = Message(author=payload['from'], to=payload['to'])
     message.subject = payload['subject']
     message.plain = strip_tags(payload['html'])
     message.rich = payload['html']
-    message.attach(name=payload['attachments'])
+    if payload['attachments'] is not None:
+        for attachment in payload['attachments']:
+            message.attach(name=attachment)
     mailer.send(message)
     logging.info('Message sent via SMTP')
     mailer.stop()
 
-
 @celery.task(base=RequestContextTask, name='resize.event.images', bind=True)
 def resize_event_images_task(self, event_id, original_image_url):
     event = safe_query(db, Event, 'id', event_id, 'event_id')