Media type versioning in Rest API - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is media type versioning in REST APIs?

Media type versioning is a way to manage different versions of an API by changing the media type in the HTTP headers, usually the Accept header. It helps clients request a specific version of the API response.

beginner

How do clients specify the API version using media type versioning?

Clients specify the API version by setting the Accept header to a custom media type that includes the version number, for example: application/vnd.example.v1+json.

intermediate

Why is media type versioning considered a clean way to version APIs?

Because it keeps the URL clean and stable, and versioning is handled through headers. This separates version concerns from resource identification and supports content negotiation.

beginner

What HTTP header is primarily used for media type versioning?

The Accept header is primarily used by clients to request a specific media type version. Servers respond with the matching Content-Type header.

beginner

Give an example of a media type string for version 2 of an API returning JSON.

An example media type string is application/vnd.example.v2+json. Here, v2 indicates version 2, and +json shows the format is JSON.

Which HTTP header do clients use to specify API version in media type versioning?

A Authorization

B Accept

C Content-Type

D User-Agent

Clients use the Accept header to tell the server which media type and version they want.

What does the media type application/vnd.example.v1+json indicate?

A Version 1 of example API returning plain text

B Version 1 of example API returning XML

C Version 2 of example API returning JSON

D Version 1 of example API returning JSON

The 'v1' means version 1 and '+json' means the format is JSON.

Why might media type versioning be preferred over URL versioning?

A It requires less server configuration

B It is easier for browsers to cache

C It keeps URLs clean and uses headers for version control

D It uses query parameters instead of headers

Media type versioning keeps URLs stable and uses HTTP headers to manage versions.

Which header does the server use to tell the client the media type version of the response?

A Content-Type

B Accept

C Cache-Control

D Host

The server responds with the Content-Type header indicating the media type and version.

If a client sends Accept: application/vnd.example.v3+json, what is it requesting?

A Version 3 of the example API in JSON format

B Version 2 of the example API in JSON format

C Version 3 of the example API in XML format

D Any version of the example API

The client requests version 3 of the API with JSON format.

Explain how media type versioning works in REST APIs and why it is useful.

Think about how clients ask for specific versions using headers.

Describe the difference between media type versioning and URL versioning in REST APIs.

Consider where the version information is placed.

Practice

1. What is the main purpose of using media type versioning in REST APIs?

easy

A. To allow clients to specify API versions via custom content types

B. To encrypt API data for security

C. To speed up API response times

D. To change the API URL structure frequently

Solution

1. Step 1: Understand media type versioning concept

   Media type versioning lets clients request specific API versions by setting custom content types in headers.

2. Step 2: Identify the main purpose

   This approach helps keep APIs backward compatible by allowing multiple versions to coexist.

3. Final Answer:

   To allow clients to specify API versions via custom content types -> Option A

4. Quick Check:

   Media type versioning = clients specify versions [OK]

Hint: Remember: version info goes in content type headers [OK]

Common Mistakes:

• Confusing versioning with encryption
• Thinking URL changes are required
• Assuming it improves speed directly

2. Which HTTP header is commonly used by clients to specify the API version in media type versioning?

easy

A. Content-Type

B. Accept

C. Authorization

D. User-Agent

Solution

1. Step 1: Identify header for version negotiation

   The client uses the Accept header to tell the server which media type and version it wants.

2. Step 2: Differentiate from other headers

   Content-Type is for request body format, Authorization is for credentials, and User-Agent identifies the client software.

3. Final Answer:

   Accept -> Option B

4. Quick Check:

   Version in Accept header [OK]

Hint: Accept header tells server what version client wants [OK]

Common Mistakes:

• Using Content-Type instead of Accept for versioning
• Confusing Authorization with version info
• Thinking User-Agent controls version

3. Given this HTTP Accept header:
Accept: application/vnd.example.v2+json
What version of the API is the client requesting?

medium

A. Version 3

B. Version 1

C. Version 2

D. No version specified

Solution

1. Step 1: Parse the media type string

   The media type is application/vnd.example.v2+json. The .v2 part indicates version 2.

2. Step 2: Confirm version number meaning

   The v2 suffix is a common pattern to specify API version 2 in media type versioning.

3. Final Answer:

   Version 2 -> Option C

4. Quick Check:

   v2 in media type means version 2 [OK]

Hint: Look for .vX in media type for version number [OK]

Common Mistakes:

• Ignoring the .v2 and picking version 1
• Confusing +json suffix as version
• Assuming no version if not in URL

4. A client sends this header:
Accept: application/vnd.example.v1+json
But the server responds with version 2 data. What is the likely cause?

medium

A. Accept header syntax is invalid

B. Client sent wrong Content-Type header

C. Server does not support version 2

D. Server ignores Accept header and defaults to latest version

Solution

1. Step 1: Analyze client request and server response

   The client requests version 1 via Accept header, but server returns version 2 data.

2. Step 2: Identify server behavior

   This usually means the server ignores the Accept header and serves the latest version by default.

3. Final Answer:

   Server ignores Accept header and defaults to latest version -> Option D

4. Quick Check:

   Server ignoring Accept header causes version mismatch [OK]

Hint: Mismatch means server likely ignores Accept header [OK]

Common Mistakes:

• Blaming client Content-Type instead of Accept
• Assuming Accept header syntax error without checking
• Thinking server lacks version 2 support

5. You want to support two API versions simultaneously using media type versioning. Which server behavior best supports this?

hard

A. Parse the Accept header and return data matching the requested version

B. Ignore Accept header and always return version 2 data

C. Use URL path versioning instead of media type versioning

D. Return an error if Accept header version is not latest

Solution

1. Step 1: Understand requirement for simultaneous version support

   To support multiple versions, the server must detect which version the client wants.

2. Step 2: Identify correct server behavior

   Parsing the Accept header and returning matching version data allows backward compatibility and coexistence.

3. Final Answer:

   Parse the Accept header and return data matching the requested version -> Option A

4. Quick Check:

   Server parses Accept header to serve requested version [OK]

Hint: Server must read Accept header to serve correct version [OK]

Common Mistakes:

• Ignoring Accept header and forcing one version
• Switching to URL versioning instead of media type
• Returning errors instead of supporting old versions