title: How to set up Airflow Send Email?
body: <p>I followed online tutorial to set up Email SMTP server in airflow.cfg as below:</p>
  
  <pre><code>[email]
  email_backend = airflow.utils.email.send_email_smtp
  
  
  [smtp]
  # If you want airflow to send emails on retries, failure, and you want to use
  # the airflow.utils.email.send_email_smtp function, you have to configure an
  # smtp server here
  smtp_host = smtp.gmail.com
  smtp_starttls = True
  smtp_ssl = False
  # Uncomment and set the user/pass settings if you want to use SMTP AUTH 
  # smtp_user =                       
  # smtp_password =  
  smtp_port = 587
  smtp_mail_from = myemail@gmail.com
  </code></pre>
  
  <p>And my DAG is as below:</p>
  
  <pre><code>from datetime import datetime
  from airflow import DAG
  from airflow.operators.dummy_operator import DummyOperator
  from airflow.operators.python_operator import PythonOperator
  from airflow.operators.email_operator import EmailOperator
  
  def print_hello():
      return 'Hello world!'
  
  default_args = {
          'owner': 'peter',
          'start_date':datetime(2018,8,11),
  }
  
  dag = DAG('hello_world', description='Simple tutorial DAG',
            schedule_interval='* * * * *',
            default_args = default_args, catchup=False)
  
  dummy_operator = DummyOperator(task_id='dummy_task', retries=3, dag=dag)
  
  hello_operator = PythonOperator(task_id='hello_task', python_callable=print_hello, dag=dag)
  
  email = EmailOperator(
          task_id='send_email',
          to='to@gmail.com',
          subject='Airflow Alert',
          html_content=""" &lt;h3&gt;Email Test&lt;/h3&gt; """,
          dag=dag
  )
  
  email &gt;&gt; dummy_operator &gt;&gt; hello_operator
  </code></pre>
  
  <p>I assumed the email operator will run after the other two operators and then send me an email.
  But email was not sent to me.
  I really appreciate your help. Thank you very much.</p>
  
  <p>Best</p>