System and method for validating documentation of representational state transfer (REST) services

• US 9,621,440 B2
• Filed: 08/29/2013
• Issued: 04/11/2017
• Est. Priority Date: 08/31/2012
• Status: Expired due to Fees

• Current Assignee: Rackspace US Incorporated (Apollo Global Management, Inc.)
• Original Assignee: Rackspace US Incorporated (Apollo Global Management, Inc.)
• Inventors: Williams, Jorge Luis, Cramer, David
• Primary Examiner(s): Greene, Joseph
• Application Number:
  US14/013,930
• Publication Number:
  US 20140068047A1
• Time in Patent Office: 1,321 Days
• Field of Search: 709223
• CPC Class Codes: H04L 41/5077 wherein the managed service relates to simple transport services, i.e. providing only network infrastructure
• CPC Class Codes: H04L 43/50 Testing arrangements
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]

Abstract

A validation tool is provided for a representational state transfer (REST) service. In one embodiment, a method for validating documentation of a REST service includes including detecting one or more messages for a REST service by a validator, wherein the one or more messages are intercepted for the REST service, translating documentation of the REST service, by the validator, into a representation of an automaton, and validating the one or more messages by the validator based on the automaton, wherein validation of the messages determines conformance of the REST service to the documentation of the REST service.

Claims

1. A method for validating documentation of a representational state transfer (REST) service, the method comprising:

detecting, by a validator, one or more messages for a REST service;

translating, by the validator, documentation of the REST service into a representation of an automaton, wherein the automaton is a state machine that transitions from an initial start state to other states based on one or more current inputs;

validating, based on the automaton, the one or more messages wherein validation of the one or more messages determines conformance of the REST service to the documentation of the REST service;

after validating the one or more messages, categorizing, by the validator, a message that is not valid in accordance with a first error code that is expected to be generated by the REST service;

receiving a response from the REST service, the response including a second error code produced by the REST service in response to processing the message; and

verifying whether the first error code matches the second error code.

2. The method of claim 1, wherein the one or more messages include at least one of client and server application messages.

3. The method of claim 1, wherein the one or more messages are functional test messages for testing functions of the REST service.

4. The method of claim 1, wherein the documentation is a machine readable description of the XML Web Application Description Language (WADL).

5. The method of claim 1, wherein translating documentation of the REST service includes parsing the documentation, validating the documentation against schema, and normalizing the documentation.

6. The method of claim 1, wherein the automaton is a representation in an XML format of URL paths and URI resources for validating messages for the REST service.

7. The method of claim 1, further comprising optimizing the automaton by reducing one or more of stages and paths of the automaton.

8. The method of claim 1, wherein translating documentation of the REST service includes reducing the number of states of the automaton, wherein each optimization stage is an XSLT that takes a checker document as input and creates a checker document with less states as output.

9. The method of claim 7, wherein optimizing includes one or more of converting simple type checks in URLXSD steps into regular expression URL steps, compressing multiply regular extension check into a single check, and compressing multiple Boolean XPATH expressions into a single expression.

10. The method of claim 1, wherein validating the one or more messages is performed as a preprocessing step.

11. The method of claim 1, wherein the validator is incorporated into existing REST services and does not require a change to existing functions of the REST service.

12. The method of claim 1, wherein the validator checks for drift simultaneously between REST services and functional tests for the REST service.

13. The method of claim 1, further comprising a XSLT checker step to perform a transformation of a message before validating the message.

14. The method of claim 1, further comprising using a WADL plain parameter to connect a restricted type of a widget WADL to a post operation.

15. The method of claim 1, wherein validating includes

parsing a machine-readable XML description of HTTP-based web applications to translate documentation;

validating documentation of the REST service against WADL schema;

normalizing the WADL;

converting the WADL to a checker format;

running through the optimization stages; and

validating the message against checker schema.

16. The method of claim 1, further comprising filtering malformed messages, by the validator, from implementation of the REST service and reporting errors, by the validator, to identify documentation and REST service discrepancy.

17. The method of claim 1, wherein the validator is provided with capabilities based on authorization of a user.

18. The method of claim 1, wherein the validator logs stages of the automaton that are visited.

19. A non-transitory computer-accessible storage medium storing program instructions that when executed by a computer cause the computer to implement a representational state transfer (REST) service validator configured to:

translate documentation of the REST service into a representation of an automaton, wherein the automaton is a state machine that transitions from an initial start state to other states based on one or more current inputs;

validate, based on the automaton, the one or more messages, wherein validation of the one or more messages determines conformance of the REST service to the documentation of the REST service, wherein after validating the one or more messages, the validator is further configured to;

categorize a message that is not valid in accordance with a first error code that is expected to be generated by the REST service;

receive a response from the REST service, the response including a second error code produced by the REST service in response to processing the message; and

verify whether the first error code matches the second error code.

20. The non-transitory computer-accessible storage medium of claim 19, wherein the one or more messages include at least one of client and server application messages.

21. The non-transitory computer-accessible storage medium of claim 19, wherein the one or more messages are functional test messages for testing functions of the REST service.

22. The non-transitory computer-accessible storage medium of claim 19, wherein the documentation is a machine readable description of the XML Web Application Description Language (WADL).

23. The non-transitory computer-accessible storage medium of claim 19, wherein translating documentation of the REST service include parsing the documentation, validating the documentation against schema, and normalizing the documentation.

24. The non-transitory computer-accessible storage medium of claim 19, wherein the automaton is a representation in an XML format of URL paths and URI resources for validating messages for the REST service.

25. The non-transitory computer-accessible storage medium of claim 19, further comprising optimizing the automaton by reducing one or more of stages and paths of the automaton.

26. The non-transitory computer-accessible storage medium of claim 19, wherein translating documentation of the REST service includes reducing the number of states of the automaton, wherein each optimization stage is an XSLT that takes a checker document as input and creates a checker document with less states as output.

27. The non-transitory computer-accessible storage medium of claim 25, wherein optimizing includes one or more of converting simple type checks in URLXSD steps into regular expression URL steps, compressing multiply regular extension check into a single check, and compressing multiple Boolean XPATH expressions into a single expression.

28. The non-transitory computer-accessible storage medium of claim 19, wherein validation of the one or more messages is performed as a preprocessing step.

29. The non-transitory computer-accessible storage medium of claim 19, wherein the validator is incorporated into existing REST services and does not require a change to existing functions of the REST service.

30. The non-transitory computer-accessible storage medium of claim 19, wherein the validator checks for drift simultaneously between REST services and functional tests for the REST service.

31. The non-transitory computer-accessible storage medium of claim 19, further comprising a XSLT checker step to perform a transformation of a message before validating the message.

32. The non-transitory computer-accessible storage medium of claim 19, further comprising using a WADL plain parameter to connect a restricted type of a widget WADL to a post operation.

33. The non-transitory computer-accessible storage medium of claim 19, wherein validation includes

parsing the machine-readable XML description of HTTP-based web applications to translate documentation;

validating documentation against WADL schema;

normalizing the WADL;

converting the WADL to a checker format;

running through the optimization stages; and

validating messages against checker schema.

34. The non-transitory computer-accessible storage medium of claim 19, further comprising filtering malformed messages, by the validator, from implementation of the REST service and reporting errors, by the validator, to identify documentation and REST service discrepancy.

35. The non-transitory computer-accessible storage medium of claim 19, wherein the validator is provided with capabilities based on authorization of a user.

36. The non-transitory computer-accessible storage medium of claim 19, wherein the validator logs stages of the automaton that are visited.