Your question is Identify Issues And Fixes. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You're a backend engineer at Klaviyo. This function sends a bulk email campaign to every subscriber in a segment. It shipped and is now dispatching real marketing email, but it has already caused two production incidents.
def send_campaign(campaign_id, segment_id, extra_headers={}):
conn = db.connect()
cursor = conn.cursor()
query = f"SELECT id, email FROM subscribers WHERE segment_id = {segment_id}"
cursor.execute(query)
subscribers = cursor.fetchall()
sent_count = 0
for subscriber_id, email in subscribers:
try:
headers = extra_headers
headers["X-Campaign-Id"] = str(campaign_id)
mailer.send(to=email, campaign_id=campaign_id, headers=headers)
sent_count += 1
except:
pass
return sent_count
Identify the issues in this code and explain, in your own words, exactly how each one would fail in production and how you would fix it.