RESTful API design for devices in IOT Protocols - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the HTTP method for retrieving device data.

IOT Protocols

curl -X [1] http://api.example.com/devices/123

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

APOST

BGET

CDELETE

DPUT

Attempts:

3 left

💡 Hint

Common Mistakes

Using POST instead of GET to retrieve data.

Confusing DELETE with GET.

The GET method is used to retrieve data from a server without changing it.

2fill in blank

medium

Complete the code to update device settings using the correct HTTP method.

IOT Protocols

curl -X [1] -d '{"mode":"eco"}' http://api.example.com/devices/123/settings

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

AHEAD

BGET

CPUT

DDELETE

Attempts:

3 left

💡 Hint

Common Mistakes

Using GET instead of PUT for updates.

Using DELETE when intending to update.

PUT is used to update or replace a resource on the server.

3fill in blank

hard

Fix the error in the API endpoint to correctly delete a device.

IOT Protocols

curl -X DELETE http://api.example.com/devices/[1]

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

A123

Bdevice_id

Csettings

Dupdate

Attempts:

3 left

💡 Hint

Common Mistakes

Using a placeholder name instead of the actual device ID.

Using 'settings' or 'update' in the URL when deleting.

The endpoint must specify the device ID to delete that specific device.

4fill in blank

hard

Fill both blanks to create a JSON response showing device status and battery level.

IOT Protocols

{
  "status": "[1]",
  "battery": [2]
}

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

Aonline

Boffline

C85

D100

Attempts:

3 left

💡 Hint

Common Mistakes

Putting battery level in quotes making it a string.

Using 'offline' when the device is online.

The device is online and the battery level is 85 percent.

5fill in blank

hard

Fill all three blanks to define a RESTful API route for creating a new device with POST method.

IOT Protocols

POST [1] HTTP/1.1
Host: api.example.com
Content-Type: [2]

[3]

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

A/devices

Bapplication/json

C{"name":"SensorX","type":"temperature"}

D/device

Attempts:

3 left

💡 Hint

Common Mistakes

Using singular '/device' instead of '/devices'.

Wrong content type like 'text/plain'.

Missing or invalid JSON body.

The POST request targets the '/devices' endpoint with JSON content type and a JSON body describing the new device.

Practice

1. Which HTTP method is typically used to retrieve data from a device in a RESTful API?

easy

A. DELETE

B. GET

C. PUT

D. POST

Solution

1. Step 1: Understand HTTP methods in REST

   GET is used to request data without changing it, ideal for reading device info.

2. Step 2: Match method to action

   Since retrieving data means reading, GET fits best over POST, PUT, or DELETE.

3. Final Answer:

   GET -> Option B

4. Quick Check:

   Retrieve data = GET [OK]

Hint: GET always fetches data without changing it [OK]

Common Mistakes:

• Confusing POST with GET for data retrieval
• Using DELETE to get data
• Thinking PUT retrieves data

2. Which of the following is the correct RESTful URL to update the settings of a device with ID 123?

easy

A. /update/device/123

B. /device/123/update

C. /devices/settings/123

D. /devices/123/settings

Solution

1. Step 1: Identify RESTful URL structure

   RESTful URLs use nouns and hierarchy: resource then ID then sub-resource.

2. Step 2: Check options for correct pattern

   /devices/123/settings correctly shows device resource, ID, then settings sub-resource.

3. Final Answer:

   /devices/123/settings -> Option D

4. Quick Check:

   Resource/ID/sub-resource = /devices/123/settings [OK]

Hint: Use resource/ID/sub-resource format for REST URLs [OK]

Common Mistakes:

• Placing ID after sub-resource
• Using verbs like 'update' in URL
• Mixing singular and plural resource names

3. Given this RESTful API call: DELETE /devices/456, what is the expected result?

medium

A. Remove device 456 from the system

B. Update device 456 information

C. Retrieve device 456 details

D. Create a new device with ID 456

Solution

1. Step 1: Understand DELETE method purpose

   DELETE removes the specified resource from the server.

2. Step 2: Apply to device 456

   DELETE /devices/456 means remove device with ID 456 from the system.

3. Final Answer:

   Remove device 456 from the system -> Option A

4. Quick Check:

   DELETE method = remove resource [OK]

Hint: DELETE removes resources, not fetch or update [OK]

Common Mistakes:

• Thinking DELETE retrieves data
• Confusing DELETE with POST or PUT
• Assuming DELETE creates resources

4. You wrote this API call to update a device: POST /devices/789 but it creates a new device instead. What is the likely mistake?

medium

A. Using POST instead of PUT for update

B. Missing device ID in URL

C. Using GET method instead of POST

D. Incorrect device ID format

Solution

1. Step 1: Understand POST vs PUT

   POST usually creates new resources; PUT updates existing ones.

2. Step 2: Analyze the API call

   POST /devices/789 creates new device; to update, use PUT /devices/789.

3. Final Answer:

   Using POST instead of PUT for update -> Option A

4. Quick Check:

   Update needs PUT, not POST [OK]

Hint: Use PUT to update, POST to create [OK]

Common Mistakes:

• Using POST for updates
• Confusing GET with POST
• Ignoring HTTP method meaning

5. You want to design a RESTful API to control multiple devices' power state at once. Which design is best?

hard

A. PUT /device/{id}/power for each device separately

B. GET /devices/power to fetch all power states

C. POST /devices/power with JSON list of device IDs and states

D. DELETE /devices/power to reset all devices

Solution

1. Step 1: Identify batch update needs

   To control many devices at once, send a batch request with data.

2. Step 2: Match HTTP method and URL

   POST /devices/power with JSON list allows updating multiple devices in one call.

3. Step 3: Evaluate other options

   GET fetches data, PUT is per device, DELETE resets devices--none fit batch control well.

4. Final Answer:

   POST /devices/power with JSON list of device IDs and states -> Option C

5. Quick Check:

   Batch update = POST with data list [OK]

Hint: Use POST with data list for batch device updates [OK]

Common Mistakes:

• Using GET to change device states
• Trying PUT for batch updates
• Using DELETE to control power