How to become a Tickstar
Do our Test – Exam A
We want to strengthen our team with even more skilled developers - we hope that you are one of them. To be able to screen candidates efficiently, we have designed a task requiring a mix of skills - just as in real life. We hope that you will enjoy it. Good luck!
1. Task
The task consists of developing an application that decrypts the content of a publicly available file using a web service published by Tickstar. Upon decryption, a secret message is revealed enabling you to take the next step towards becoming a Tickstar.
2. Purpose
We need to verify candidates' problem solving skills. Parsing text from a file is considered as trivial, however making a web service call and constructing the input message might be difficult if you haven't worked with stuff like that earlier. We will provide support and answers to your questions, but we appreciate if other resources are exhausted first.
Don’t worry if you are not able to solve the task, it will not automatically render you a fail in the recruitment process. Remember: as long as you can describe how you did it and motivate why you've chosen a particular solution, we don't consider it as a fail. The most important thing is that we understand your methodology.
3. Restrictions
You are free to use tools, integration platforms and programming languages of your choice. However please keep in mind that we want you to solve the task programmatically. While we are aware that it is possible to solve the task with a simple HTTP POST from the command line, this is not the way we want it to be done. Putting the command in a shell script would be slightly more creative, but still not satisfactory enough for us.
4. Support and contact
Any questions or contact with Tickstar regarding this task are addressed if you e-mail us with the following subject: TickstarExamA - ${FirstName + LastName}
5. Decrypt secret message through TickstarDecoderService
Please read the following steps carefully in order to understand the task. If in any doubt, please do not hesitate to contact us.
a) The contents of the file that we want you to decrypt is available at https://www.tickstar.com/wp-content/uploads/encrypted.txt.
You could either solve the task by reading the encrypted message from the above URL or from your local file system. If you store the file on your file system try to avoid changing the encoding (UTF-8) of the file since it can corrupt the contents of the file.
b) The Web Service is described by a WSDL-file that is available at http://smp.peppol.me/recr-ws/TickstarDecoderService?wsdl.
The Web Service call it self should be made towards:
http://smp.peppol.me/recr-ws/TickstarDecoderService.
Create a Web Service client that is able to send requests and receive responses from the described Web Service.
c) Input to the Web Service
The Web Service expects an XML-formatted input, TickstarInputMessage. The expected XML is described by an XSD available at http://smp.peppol.me:80/recr-ws/TickstarDecoderService?xsd=1.
The XSD defines an XML containing the following elements, please follow the guidelines marked in green when putting information in these fields (all fields are mandatory in order to get a valid response from the web service):
- Contact->FirstName – Your first name
- Contact->LastName – Your last name
- Contact->BirthDate – Your birth date
- Contact->EmailAddress – Your email address
- Input – Put the whole encrypted message described in section 5.a
d) Output of the Web Service
The structure of the XML that the web service responds with is described by an XSD available at:
http://smp.peppol.me/recr-ws/TickstarDecoderService?xsd=2
It contains a single element:
Output
This field will contain the decrypted message fully readable or possibly an error message.
Hint
If the output would only contain a bunch of random characters, then the most likely cause is that the encrypted input message has been corrupted (or encoding changed) when the request was constructed. Make sure that you do not apply any changes to the encrypted text, work with raw bytes. Use UTF-8 encoding whenever needed and it should work.