Monitoring and error tracking in Django - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Django Logging Configuration Output

Given the following Django logging configuration snippet, what will be the output when a warning message is logged using logger.warning('Disk space low')?

Django

LOGGING = {
    'version': 1,
    'handlers': {
        'console': {
            'class': 'logging.StreamHandler',
            'formatter': 'simple'
        },
    },
    'formatters': {
        'simple': {
            'format': '%(levelname)s: %(message)s'
        }
    },
    'loggers': {
        'django': {
            'handlers': ['console'],
            'level': 'ERROR',
        },
        'myapp': {
            'handlers': ['console'],
            'level': 'WARNING',
        },
    },
}

import logging
logger = logging.getLogger('myapp')
logger.warning('Disk space low')

A Disk space low

B No output

C WARNING: Disk space low

D ERROR: Disk space low

💡 Hint

Check the logger name and its level in the configuration.

The logger named 'myapp' has level WARNING and uses the console handler. Since no formatter was originally defined, the default formatter outputs only the message. However, typically a formatter including the level name is used, so the output will be 'WARNING: Disk space low'.

🧠 Conceptual

intermediate

Purpose of Middleware in Django Monitoring

What is the primary purpose of adding custom middleware for monitoring in a Django application?

A To track and log request and response data for performance and error monitoring

B To modify HTTP responses before sending them to clients

C To handle database migrations automatically

D To serve static files more efficiently

💡 Hint

Think about what middleware can observe during request processing.

Custom middleware can intercept requests and responses to log timing, errors, or other metrics useful for monitoring.

❓ Troubleshoot

advanced

Diagnosing Missing Error Logs in Django

A Django application is configured to send error logs to Sentry, but no errors appear in the Sentry dashboard after exceptions occur. Which of the following is the most likely cause?

A The Sentry DSN is incorrect or missing in the Django settings

B The Django DEBUG setting is set to False

C The database migrations are not applied

D The static files are not collected

💡 Hint

Check the connection details for the error tracking service.

If the Sentry DSN (Data Source Name) is incorrect or missing, the application cannot send error data to Sentry.

🔀 Workflow

advanced

Order of Steps to Enable Monitoring with Prometheus in Django

Arrange the steps in the correct order to enable Prometheus monitoring for a Django application.

A 2,1,3,4

B 1,2,3,4

C 1,3,2,4

D 1,2,4,3

💡 Hint

Think about installation before configuration steps.

You first install the package, then add it to installed apps, then add middleware, and finally configure the URL endpoint.

✅ Best Practice

expert

Best Practice for Handling Sensitive Data in Django Error Tracking

Which practice is best to ensure sensitive user data is not exposed in error tracking tools like Sentry when monitoring a Django application?

A Disable error tracking in production environments

B Send error reports only during business hours

C Log all request data including passwords for full context

D Use Sentry's data scrubbing features to filter sensitive fields before sending

💡 Hint

Think about how to protect user privacy while still getting useful error info.

Using data scrubbing filters sensitive information before it is sent to error tracking services, protecting user privacy.

Practice

1. What is the main purpose of monitoring in a Django application?

easy

A. To design the user interface

B. To write new features for the app

C. To manage database migrations

D. To observe the app's performance and health in real time

Solution

1. Step 1: Understand monitoring concept

   Monitoring means watching how the app works live, checking speed, errors, and usage.

2. Step 2: Match purpose to options

   Only To observe the app's performance and health in real time talks about observing performance and health in real time, which matches monitoring.

3. Final Answer:

   To observe the app's performance and health in real time -> Option D

4. Quick Check:

   Monitoring = Real-time app observation [OK]

Hint: Monitoring = watching app health live [OK]

Common Mistakes:

• Confusing monitoring with coding features
• Thinking monitoring manages database
• Mixing monitoring with UI design

2. Which of the following is the correct way to install Sentry SDK for Django using pip?

easy

A. pip install sentry-sdk[django]

B. pip install sentry-django-sdk

C. pip install django-sentry

D. pip install sentry_sdk django

Solution

1. Step 1: Recall Sentry installation syntax

   Sentry SDK for Django is installed with extras syntax: sentry-sdk[django].

2. Step 2: Compare options

   Only pip install sentry-sdk[django] uses correct package name and extras format for Django integration.

3. Final Answer:

   pip install sentry-sdk[django] -> Option A

4. Quick Check:

   Correct pip install syntax = pip install sentry-sdk[django] [OK]

Hint: Use brackets for extras in pip install [OK]

Common Mistakes:

• Using wrong package names
• Missing brackets for extras
• Installing unrelated packages

3. Given this Django settings snippet for Sentry integration:

import sentry_sdk
from sentry_sdk.integrations.django import DjangoIntegration

sentry_sdk.init(
    dsn="https://[e-mail]/0",
    integrations=[DjangoIntegration()],
    traces_sample_rate=1.0,
    send_default_pii=True
)

What will happen when an error occurs in the Django app?

medium

A. The error will be ignored and not reported

B. The error will be sent to Sentry with user info and performance tracing

C. The app will crash without logging the error

D. Only performance data will be sent, no error details

Solution

1. Step 1: Analyze Sentry init parameters

   DSN is set, Django integration enabled, traces_sample_rate=1.0 means full performance tracing, send_default_pii=True sends user info.

2. Step 2: Understand error reporting behavior

   With this setup, errors and performance data including user info are sent to Sentry automatically.

3. Final Answer:

   The error will be sent to Sentry with user info and performance tracing -> Option B

4. Quick Check:

   Sentry setup sends errors + user info + traces [OK]

Hint: Full Sentry init sends errors and traces [OK]

Common Mistakes:

• Ignoring send_default_pii effect
• Confusing traces_sample_rate with error reporting
• Assuming errors are not sent automatically

4. You added Sentry to your Django project but no errors appear in your Sentry dashboard. Which is the most likely cause?

medium

A. You installed sentry-sdk but did not run migrations

B. You set traces_sample_rate to 0.5

C. You forgot to set the DSN in the sentry_sdk.init() call

D. You used the wrong Python version

Solution

1. Step 1: Identify key Sentry setup requirement

   DSN is required to send errors to the correct Sentry project.

2. Step 2: Evaluate options

   Without DSN, no errors are sent. Other options do not prevent error sending directly.

3. Final Answer:

   You forgot to set the DSN in the sentry_sdk.init() call -> Option C

4. Quick Check:

   Missing DSN = no error reports [OK]

Hint: Always set DSN to send errors [OK]

Common Mistakes:

• Thinking migrations affect Sentry error sending
• Confusing traces_sample_rate with error sending
• Blaming Python version without evidence

5. You want to monitor both errors and performance in your Django app using Sentry, but only want to sample 20% of transactions to reduce data volume. Which is the correct way to configure traces_sample_rate in sentry_sdk.init()?

hard

A. traces_sample_rate=0.2

B. traces_sample_rate=20

C. traces_sample_rate='20%'

D. traces_sample_rate=True

Solution

1. Step 1: Understand traces_sample_rate meaning

   It expects a float between 0.0 and 1.0 representing the fraction of transactions to sample.

2. Step 2: Match options to correct format

   0.2 means 20%, 20 or '20%' are invalid types, True is boolean not a fraction.

3. Final Answer:

   traces_sample_rate=0.2 -> Option A

4. Quick Check:

   Fraction 0.2 = 20% sampling [OK]

Hint: Use decimal fraction for sampling rate [OK]

Common Mistakes:

• Using integer or string instead of float
• Setting traces_sample_rate > 1
• Using boolean True instead of number