REST API Best Practices: Versioning, Pagination, and Filtering Quiz Quiz

Enhance your understanding of REST API best practices with this quiz focusing on API versioning, pagination, and filtering concepts. Ideal for developers aiming to design scalable and maintainable APIs using industry-standard techniques for resource management.

1. API Versioning Location

   Which of the following is a commonly recommended way to specify the version of a REST API in a request?

   1. Enclosed in the request body
   2. Within the URL path, such as /v1/resources
   3. Using a custom HTTP status header
   4. As a query parameter named ‘ver’

   Explanation: Placing the version in the URL path is one of the most widely accepted methods for API versioning, making the version clear and explicit in the resource location. Using a query parameter is less favored as it can complicate resource identification. Enclosing version information in the body is not ideal because the version needs to be determined before parsing the body. A custom HTTP status header is not a standard approach and may introduce unnecessary complexity.

2. Purpose of Pagination

   Why is implementing pagination considered a best practice when designing REST APIs that return large collections of data?

   1. It encrypts sensitive fields within API responses.
   2. It allows real-time authentication of all records.
   3. It reduces server response times and limits data transfer for each request.
   4. It increases the number of available HTTP verbs.

   Explanation: Pagination divides large data sets into smaller, manageable parts, making responses faster and reducing bandwidth usage. Encryption relates to data security rather than pagination. Increasing HTTP verbs or enabling real-time authentication are unrelated to the concept of pagination in APIs.

3. Parameter Naming in Pagination

   Which parameter names are most commonly used to control pagination in REST APIs for defining the page size and the starting point?

   1. maxrows and begin
   2. first and count
   3. limit and offset
   4. startnum and totallist

   Explanation: The terms 'limit' and 'offset' are widely recognized for specifying how many items to return and where to start in the collection. 'Maxrows' and 'begin' or 'first' and 'count' are not standard and could confuse users. 'Startnum' and 'totallist' are also uncommon and not part of widely accepted best practices.

4. Filtering Resources

   In a REST API, how are filtering operations typically provided to clients requesting resources, such as searching for users with a specific role?

   1. By encoding filters in a custom header
   2. By including filter criteria as query parameters in the URL
   3. By returning all data for client-side filtering
   4. By embedding filter details inside PUT requests only

   Explanation: Query parameters allow clients to request filtered results directly from the server, keeping responses concise. Custom headers are not standard for filters and complicate usage. Filtering only with PUT requests is incorrect, as GET requests are typically used. Returning all data for the client to filter is inefficient and defeats the purpose of server-side filtering.

5. Versioning Without Breaking Changes

   What is a key reason for introducing versioning in a REST API?

   1. To safely introduce changes without breaking existing client integrations
   2. To improve the readability of JSON responses
   3. To make HTTP requests faster
   4. To enable the use of custom HTTP methods

   Explanation: Versioning allows API providers to update or modify endpoints while maintaining compatibility for users relying on earlier versions. Making requests faster or the JSON more readable are unrelated to versioning. Custom HTTP methods are not introduced or enabled specifically through versioning.

6. Page and Per-Page Parameters

   When using 'page' and 'per_page' as pagination parameters, what does the 'per_page' value represent?

   1. The maximum number of resources returned in one response page
   2. The number of fields included in each item
   3. The position of the first record in the collection
   4. The total number of pages available

   Explanation: 'Per_page' specifies how many resources to include in each paginated response, improving efficiency and usability. It does not refer to the number of fields per item or denote the position of a record. While the total number of pages is related, 'per_page' determines page item count itself, not the overall total.

7. Filtering with Multiple Criteria

   How should a REST API handle multiple filter criteria, such as filtering products by both category and price range?

   1. By allowing several query parameters, like category=booksu0026price_min=10
   2. By using a custom verb for filtering requests
   3. By accepting a comma-separated list in the path
   4. By nesting filters in the request body of a GET request

   Explanation: Using multiple query parameters is a clear, standards-based way to pass several filter criteria in REST APIs. Comma-separated values in the path can lead to parsing issues. Custom verbs do not conform to HTTP conventions. Placing filters within the body of a GET request is against common HTTP practices.

8. Indicating Available Versions

   What is a straightforward way for a REST API to inform clients which versions are available or recommended?

   1. Only mentioning versions in the homepage's footer
   2. Omitting versioning details from all communications
   3. Including version information in the API documentation and within response headers
   4. Returning a 404 status for unsupported versions

   Explanation: Documenting versions and mentioning them in response headers makes it easy for clients to discover version options. Returning a 404 does not provide proactive guidance. Omitting details or limiting them to a homepage footer is unhelpful for developers consuming your API.

9. Choosing Between Offset and Cursor Pagination

   Which scenario commonly favors cursor-based pagination over offset-based pagination in REST APIs?

   1. When resources have single-character IDs
   2. When the dataset is large and frequently changing
   3. When the API does not expose any identifiers
   4. When datasets are static and rarely updated

   Explanation: Cursor-based pagination provides stability and consistency when retrieving large, dynamic data collections, as it avoids issues caused by data shifts between requests. Offset-based pagination works for small or static datasets but can skip or duplicate items in changing data. The length of resource IDs or absence of IDs does not determine which pagination style to use.

10. Filtering Null or Missing Values

    How can a client request only those resources where a specific field is missing or has a null value using a REST API with filtering?

    1. By including a parameter named _notfound
    2. By passing a query parameter indicating the field equals null, like status=null
    3. By omitting the field from the URL entirely
    4. By using a POST request without any body content

    Explanation: Specifying a filter where the field equals 'null' in the query parameter signals the server to return resources missing that value. Omitting the field from the URL does not explicitly request null values. A parameter named '_notfound' is non-standard and unlikely to be effective. Making a POST request without a body does not serve this filtering purpose.