If you're working with Books and need to validate / store ISBN codes, it can be hard to know if they are valid. This component aims to help on that and, at the same time, present book's information in a more readable format.

It also aims to showcase best practices when integrating with external services. With this component you can learn how to consume a REST API, with a focus on how to modify a dynamic response using the OnAfterResponse event.

To sum up:

• This Service Module checks if a ISBN-13 is valid and works as an utility when ISBN codes need to be checked, being useful to avoid storing bad data in a Library's database, for instance. For a valid ISBN-13 I considered the text may include hyphens or spaces but no other chars.

• You can also convert older ISBN-10 codes to the recent ISBN-13 format, allowing for a future database uniformizing, if needed. I convert the first 9 digits of a 10 digit ISBN to a 13 digit ISBN text output (may include hyphens or spaces but no other chars), returning NullTextIdentifier if it can't be converted to a valid ISBN-13. This action is also a function.

• Besides ISBN-13 validations and conversions, another feature added is that we can retrieve book details from OpenLibrary's API and fetch it as a JSON object. The API's url used is https://openlibrary.org. I also add exception handling for invalid ISBN-13 or no details found (empty response from the API).