EmailOperator for notifications in Apache Airflow - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the EmailOperator from Airflow.

Apache Airflow

from airflow.providers.smtp.operators.email import [1]

Drag options to blanks, or click blank then click option'

AEmailOperatorTask

BEmailOperator

CEmailNotify

DEmailTask

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect class names like EmailNotify or EmailTask.

Forgetting to import from airflow.providers.smtp.operators.email.

The correct import is EmailOperator from airflow.providers.smtp.operators.email.

2fill in blank

medium

Complete the code to create an EmailOperator task named 'send_email'.

Apache Airflow

send_email = EmailOperator(task_id='send_email', to='[e-mail]', subject='Test', [1]='This is a test email', dag=dag)

Drag options to blanks, or click blank then click option'

Abody

Bemail_body

Chtml_content

Dcontent

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'html_content' or 'content' instead of 'body'.

Misspelling the parameter name.

The EmailOperator uses body to specify the email body content.

3fill in blank

hard

Fix the error in the EmailOperator initialization by completing the missing parameter for the sender email.

Apache Airflow

send_email = EmailOperator(task_id='send_email', to='[e-mail]', subject='Test', body='Hello', [1]='[e-mail]', dag=dag)

Drag options to blanks, or click blank then click option'

Aemail_from

Bsender

Cfrom

Dfrom_email

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'from' which is a reserved keyword in Python.

Using 'sender' or 'email_from' which are incorrect parameter names.

The correct parameter to specify the sender email is from_email.

4fill in blank

hard

Fill both blanks to create an EmailOperator that sends to multiple recipients and includes a CC address.

Apache Airflow

send_email = EmailOperator(task_id='send_email', to=[1], cc=[2], subject='Hello', body='Hi there', from_email='[e-mail]', dag=dag)

Drag options to blanks, or click blank then click option'

A['[e-mail]', '[e-mail]']

B'[e-mail]'

C'[e-mail]'

D['[e-mail]']

Attempts:

3 left

💡 Hint

Common Mistakes

Using a string instead of a list for multiple recipients.

Using a string for cc when a list is expected.

The to parameter accepts a list of recipients, and cc also accepts a list of emails.

5fill in blank

hard

Fill all three blanks to create an EmailOperator with attachments, a custom mime subtype, and a reply-to address.

Apache Airflow

send_email = EmailOperator(task_id='send_email', to='[e-mail]', subject='Report', body='See attached', files=[1], mime_subtype=[2], reply_to=[3], from_email='[e-mail]', dag=dag)

Drag options to blanks, or click blank then click option'

A['/path/to/report.pdf']

B'mixed'

C'[e-mail]'

D'alternative'

Attempts:

3 left

💡 Hint

Common Mistakes

Passing files as a string instead of a list.

Using wrong mime subtype like 'alternative' when attachments exist.

Omitting the reply_to parameter or using wrong format.

The files parameter takes a list of file paths, mime_subtype is usually 'mixed' for attachments, and reply_to is the email address for replies.

Practice

1. What is the primary purpose of the EmailOperator in Airflow?

easy

A. To store logs of task executions

B. To schedule tasks at specific times

C. To monitor CPU usage of Airflow workers

D. To send emails automatically from Airflow tasks

Solution

1. Step 1: Understand EmailOperator's role

   EmailOperator is designed to send emails triggered by Airflow tasks.

2. Step 2: Compare with other options

   Scheduling tasks, storing logs, and monitoring CPU are handled by other Airflow components, not EmailOperator.

3. Final Answer:

   To send emails automatically from Airflow tasks -> Option D

4. Quick Check:

   EmailOperator = send emails [OK]

Hint: EmailOperator is for sending emails, not scheduling [OK]

Common Mistakes:

• Confusing EmailOperator with scheduling operators
• Thinking EmailOperator manages logs or monitoring
• Assuming EmailOperator runs tasks instead of notifying

2. Which of the following is the correct way to import EmailOperator in an Airflow DAG file?

easy

A. from airflow.operators.email_operator import Email

B. from airflow.operators.email import EmailOperator

C. from airflow.operators.email_operator import EmailOperator

D. import EmailOperator from airflow.operators.email_operator

Solution

1. Step 1: Recall correct import path

   The correct import path for EmailOperator in Airflow is from airflow.operators.email_operator import EmailOperator.

2. Step 2: Check other options for syntax or naming errors

   from airflow.operators.email import EmailOperator uses wrong module name (missing '_operator'); from airflow.operators.email_operator import Email imports wrong class name; import EmailOperator from airflow.operators.email_operator uses invalid Python import syntax.

3. Final Answer:

   from airflow.operators.email_operator import EmailOperator -> Option C

4. Quick Check:

   Correct import = airflow.operators.email_operator [OK]

Hint: Use 'from airflow.operators.email_operator import EmailOperator' [OK]

Common Mistakes:

• Using wrong module path like email
• Incorrect import syntax like 'import X from Y'
• Confusing class name with module name

3. Given this Airflow task using EmailOperator:

email_task = EmailOperator(
    task_id='send_email',
    to='[e-mail]',
    subject='Test Email',
    html_content='Hello from Airflow!',
    dag=dag
)

What will happen when this task runs successfully?

medium

A. The task will send an email but with empty content

B. An email with subject 'Test Email' is sent to [e-mail]

C. No email is sent because 'to' is not a list

D. The task will fail because html_content is missing

Solution

1. Step 1: Analyze EmailOperator parameters

   The task specifies 'to' as a string email address, 'subject', and 'html_content' correctly.

2. Step 2: Understand EmailOperator behavior

   EmailOperator accepts a string or list for 'to' and sends the email with given subject and content.

3. Final Answer:

   An email with subject 'Test Email' is sent to [e-mail] -> Option B

4. Quick Check:

   Valid params = email sent [OK]

Hint: Single string 'to' is valid for EmailOperator [OK]

Common Mistakes:

• Thinking 'to' must be a list
• Assuming html_content is required to be a file
• Believing task fails without attachments

4. You wrote this EmailOperator task but it fails with an error:

email_task = EmailOperator(
    task_id='notify',
    to=['[e-mail]'],
    subject='Alert',
    html_content='Check this alert',
    dag=dag
)

What is the most likely cause of the failure?

medium

A. SMTP server is not configured in Airflow settings

B. The 'to' parameter must be a string, not a list

C. Missing 'from_email' parameter in EmailOperator

D. The 'subject' parameter cannot contain spaces

Solution

1. Step 1: Check EmailOperator parameters

   The 'to' parameter accepts a list, and 'subject' with spaces is valid.

2. Step 2: Identify common failure cause

   EmailOperator requires SMTP server setup in Airflow config; missing this causes failure.

3. Final Answer:

   SMTP server is not configured in Airflow settings -> Option A

4. Quick Check:

   SMTP setup missing = failure [OK]

Hint: Check SMTP config if EmailOperator fails [OK]

Common Mistakes:

• Assuming 'to' cannot be a list
• Thinking the 'subject' parameter cannot contain spaces
• Thinking 'from_email' is mandatory parameter

5. You want to send an email notification only when a task fails using EmailOperator. Which Airflow feature should you use to trigger the email task only on failure?

hard

A. Set trigger_rule="one_failed" on the EmailOperator task

B. Set trigger_rule="all_success" on the EmailOperator task

C. Use depends_on_past=True on the EmailOperator task

D. Set email_on_failure=False in the DAG definition

Solution

1. Step 1: Understand trigger_rule usage

   Setting trigger_rule="one_failed" makes the task run only if any upstream task fails.

2. Step 2: Evaluate other options

   all_success runs only if all succeed; depends_on_past controls task dependency on previous runs; email_on_failure is a DAG-level flag, not for task trigger.

3. Final Answer:

   Set trigger_rule="one_failed" on the EmailOperator task -> Option A

4. Quick Check:

   Trigger on failure = trigger_rule one_failed [OK]

Hint: Use trigger_rule='one_failed' to run on failure only [OK]

Common Mistakes:

• Using trigger_rule='all_success' for failure notification
• Confusing depends_on_past with failure triggers
• Misusing email_on_failure flag for task triggers