IoT analytics and dashboards in IOT Protocols - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to subscribe to the MQTT topic for receiving sensor data.

IOT Protocols

client.subscribe('[1]')

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

Adisconnect

Bconnect

Csensor/data

Dpublish

Attempts:

3 left

💡 Hint

Common Mistakes

Using MQTT client methods like 'connect' or 'publish' instead of a topic name.

The MQTT client subscribes to the topic sensor/data to receive sensor data messages.

2fill in blank

medium

Complete the code to filter incoming data points where temperature is above 30 degrees.

IOT Protocols

filtered_data = [d for d in data if d['temperature'] [1] 30]

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

A>

B<

C==

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' or '<=' which would filter lower temperatures.

The filter keeps data points where temperature is greater than 30.

3fill in blank

hard

Fix the error in the code to publish JSON data to the MQTT topic.

IOT Protocols

client.publish('sensor/data', [1].dumps(payload))

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

Axml

Bjson

Cyaml

Dcsv

Attempts:

3 left

💡 Hint

Common Mistakes

Using unsupported formats like 'yaml', 'xml', or 'csv' which cause errors.

The json.dumps() function converts the payload dictionary to a JSON string for publishing.

4fill in blank

hard

Fill both blanks to create a dictionary comprehension that maps device IDs to their latest temperature readings if above 25.

IOT Protocols

{device['id']: device['temperature'] for device in devices if device['temperature'] [1] [2]

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

A>

B25

C<

D30

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' or wrong threshold values which filter incorrect devices.

The comprehension filters devices with temperature greater than 25 and maps their IDs to temperatures.

5fill in blank

hard

Fill all four blanks to create a dictionary comprehension that maps sensor names in uppercase to their values if the value is below 50.

IOT Protocols

{ [1]: [2] for [3], [4] in sensors.items() if [2] < 50 }

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

Aname.upper()

Bvalue

Cname

Dsensor

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong variable names or forgetting to convert names to uppercase.

The comprehension maps sensor names converted to uppercase to their values, filtering values below 50.

Practice

1. What is the main purpose of an IoT analytics dashboard?

easy

A. To visually display and monitor IoT device data

B. To control IoT devices remotely

C. To store raw IoT data without processing

D. To update firmware on IoT devices

Solution

1. Step 1: Understand the role of IoT analytics

   IoT analytics processes device data to create insights.

2. Step 2: Identify dashboard function

   Dashboards show these insights visually for easy monitoring.

3. Final Answer:

   To visually display and monitor IoT device data -> Option A

4. Quick Check:

   Dashboard = Visual monitoring [OK]

Hint: Dashboards show data visually to help monitor devices [OK]

Common Mistakes:

• Confusing dashboards with device control tools
• Thinking dashboards only store data
• Assuming dashboards update device firmware

2. Which of the following is the correct JSON snippet to define a simple IoT dashboard widget showing temperature?

easy

A. {type: "gauge", title: "Temp", data: "temperature"}

B. {"widget": gauge, "title": Temp, "data": temperature}

C. {"type": "gauge", "title": "Temp", "data": "temperature"}

D. {"type": gauge, "title": "Temp", "data": temperature}

Solution

1. Step 1: Check JSON syntax rules

   Keys and string values must be in double quotes.

2. Step 2: Validate each option

   {"type": "gauge", "title": "Temp", "data": "temperature"} uses correct JSON syntax with quotes around keys and strings.

3. Final Answer:

   {"type": "gauge", "title": "Temp", "data": "temperature"} -> Option C

4. Quick Check:

   Proper JSON syntax = {"type": "gauge", "title": "Temp", "data": "temperature"} [OK]

Hint: JSON keys and strings need double quotes [OK]

Common Mistakes:

• Missing quotes around keys or string values
• Using single quotes instead of double quotes
• Leaving keys or strings unquoted

3. Given this dashboard configuration snippet:

{"widgets": [{"type": "line_chart", "data": [10, 20, 30]}]}

What will the dashboard display?

medium

A. A line chart showing points 10, 20, and 30

B. A bar chart showing points 10, 20, and 30

C. An error due to missing title field

D. A table listing values 10, 20, and 30

Solution

1. Step 1: Identify widget type

   The widget type is "line_chart", so it will display a line chart.

2. Step 2: Check data values

   Data array [10, 20, 30] are points to plot on the chart.

3. Final Answer:

   A line chart showing points 10, 20, and 30 -> Option A

4. Quick Check:

   Widget type "line_chart" = line chart display [OK]

Hint: Widget type defines chart style shown [OK]

Common Mistakes:

• Confusing line_chart with bar_chart
• Assuming missing title causes error
• Thinking data displays as a table

4. You have this dashboard JSON:

{"widgets": [{"type": "gauge", "data": temperature}]}

Why does the dashboard fail to load?

medium

A. Incorrect widget type 'gauge'

B. Missing quotes around the string 'temperature'

C. Data array is empty

D. Extra comma after last widget

Solution

1. Step 1: Check JSON syntax for data field

   Value temperature is unquoted, so JSON is invalid.

2. Step 2: Confirm correct widget type

   "gauge" is a valid widget type, so not the cause.

3. Final Answer:

   Missing quotes around the string 'temperature' -> Option B

4. Quick Check:

   Unquoted string in JSON = syntax error [OK]

Hint: Strings in JSON must have double quotes [OK]

Common Mistakes:

• Assuming widget type is wrong
• Ignoring missing quotes on strings
• Thinking empty data causes failure

5. You want to create a dashboard that alerts when temperature exceeds 75 degrees and shows a red warning. Which configuration snippet correctly adds this alert?

hard

A. {"alerts": [{"metric": "temperature", "condition": "<75", "color": "red"}]}

B. {"alerts": [{"metric": "temperature", "condition": ">=75", "color": "green"}]}

C. {"alerts": [{"metric": temperature, "condition": ">75", "color": red}]}

D. {"alerts": [{"metric": "temperature", "condition": ">75", "color": "red"}]}

Solution

1. Step 1: Identify correct alert condition

   Alert triggers when temperature is greater than 75, so condition ">75" is correct.

2. Step 2: Check alert color for warning

   Red color indicates warning, so "color": "red" is correct.

3. Step 3: Validate JSON syntax

   {"alerts": [{"metric": "temperature", "condition": ">75", "color": "red"}]} uses proper quotes around strings and keys.

4. Final Answer:

   {"alerts": [{"metric": "temperature", "condition": ">75", "color": "red"}]} -> Option D

5. Quick Check:

   Alert condition ">75" with red color = {"alerts": [{"metric": "temperature", "condition": ">75", "color": "red"}]} [OK]

Hint: Alert condition and color must match requirement [OK]

Common Mistakes:

• Using wrong comparison operator
• Missing quotes around strings
• Choosing wrong alert color