Details

    • Type: Bug Bug
    • Status: Closed
    • Priority: Blocker Blocker
    • Resolution: Fixed
    • Affects Version/s: 2.2
    • Fix Version/s: 2.2.2
    • Component/s: Web Services
    • Labels:
    • Rank:
      37497

      Description

      Some Fabio's comments originally in MDL-30878 that concerns a Coding error exception with core_role_assign_roles

      About the return value, returning null actually causes an execution error (at least on my installations).

      I took this example from the forum, but the error is the same.

      <EXCEPTION class="coding_exception">
      <MESSAGE>Coding error detected, it must be fixed by a programmer:
      PHP catchable fatal error</MESSAGE>
      <DEBUGINFO>Argument 1 passed to external_api::clean_returnvalue()
      must be an instance of external_description, null given, called in
      /var/www/moodle/moodle/webservice/rest/locallib.php on line 88 and
      defined</DEBUGINFO>
      </EXCEPTION>

      What happens is that on the webservice definition, the update_users_returns() is returning null, but a structure of the type external_description must be returned always (or at least, that is what I understand).
      This is why I've returned the id's instead of null.
      I would like to know what is your opinion about this. Another user has complained already, because a lot of webservice functions are declaring their return values as null, which raises these errors and break the webservices output, even though they do what they are supposed to do. This forum discussion is an example: http://moodle.org/mod/forum/discuss.php?d=193402

      I have seen that this behavior differs on the 2.1 implementation.
      This is why it works on 2.1 but not on 2.2: the response generator is different on each version, and on 2.2 version it does not accept null as a return value.

      So it actually seems more like a bug on the response generator then on the webservice definitions, as I thought it was.

        Issue Links

          Activity

          Hide
          Jérôme Mouneyrac added a comment -

          Hi Fabio, about the second quote, it did work in 2.1 because the REST server didn't validate the return value against the description. But it is most likely that the SOAP and XMLRPC servers failed in 2.1. Anyway good catch

          Show
          Jérôme Mouneyrac added a comment - Hi Fabio, about the second quote, it did work in 2.1 because the REST server didn't validate the return value against the description. But it is most likely that the SOAP and XMLRPC servers failed in 2.1. Anyway good catch
          Hide
          Michael de Raadt added a comment -

          Some additional information is presented in the linked duplicate issue.

          Show
          Michael de Raadt added a comment - Some additional information is presented in the linked duplicate issue.
          Hide
          Jérôme Mouneyrac added a comment -

          I found the issue, it impacts all REST call returning a description == null. Fixing it as it was done for the Zend servers...

          Show
          Jérôme Mouneyrac added a comment - I found the issue, it impacts all REST call returning a description == null. Fixing it as it was done for the Zend servers...
          Hide
          Aparup Banerjee added a comment -

          Jerome, i've had a look at the code and its parfait.

          (although i'm not sure if using null has any impact on ws/rest)

          Show
          Aparup Banerjee added a comment - Jerome, i've had a look at the code and its parfait. (although i'm not sure if using null has any impact on ws/rest)
          Hide
          Jérôme Mouneyrac added a comment -

          Thanks Apu. It is fixed the exact same way than the Zend servers. I tested on 2.2 and HEAD (the issue doesn't exist in 2.1 has the return values validation has just been added to 2.2), all works fine.

          Show
          Jérôme Mouneyrac added a comment - Thanks Apu. It is fixed the exact same way than the Zend servers. I tested on 2.2 and HEAD (the issue doesn't exist in 2.1 has the return values validation has just been added to 2.2), all works fine.
          Hide
          Eloy Lafuente (stronk7) added a comment -

          The main moodle.git repository has just been updated with latest weekly modifications. You may wish to rebase your PULL branches to simplify history and avoid any possible merge conflicts. This would also make integrator's life easier next week.

          TIA and ciao

          Show
          Eloy Lafuente (stronk7) added a comment - The main moodle.git repository has just been updated with latest weekly modifications. You may wish to rebase your PULL branches to simplify history and avoid any possible merge conflicts. This would also make integrator's life easier next week. TIA and ciao
          Hide
          Sam Hemelryk added a comment -

          Thanks Jerome - this has been integrated now.

          Show
          Sam Hemelryk added a comment - Thanks Jerome - this has been integrated now.
          Hide
          Gerard Caulfield added a comment -

          Before patch:

          <?xml version="1.0" encoding="UTF-8" ?>
          <EXCEPTION class="coding_exception">
          <MESSAGE>Coding error detected, it must be fixed by a programmer: PHP catchable fatal error</MESSAGE>
          <DEBUGINFO>Argument 1 passed to external_api::clean_returnvalue() must be an instance of external_description, null given, called in /home/moodleuser/src/moodle/pro/22/webservice/rest/locallib.php on line 88 and defined</DEBUGINFO>
          </EXCEPTION>
          

          After patch:

          <?xml version="1.0" encoding="UTF-8" ?>
          <RESPONSE>
          </RESPONSE>
          

          Test passed! =)

          Show
          Gerard Caulfield added a comment - Before patch: <?xml version= "1.0" encoding= "UTF-8" ?> <EXCEPTION class= "coding_exception" > <MESSAGE>Coding error detected, it must be fixed by a programmer: PHP catchable fatal error</MESSAGE> <DEBUGINFO>Argument 1 passed to external_api::clean_returnvalue() must be an instance of external_description, null given, called in /home/moodleuser/src/moodle/pro/22/webservice/ rest /locallib.php on line 88 and defined</DEBUGINFO> </EXCEPTION> After patch: <?xml version= "1.0" encoding= "UTF-8" ?> <RESPONSE> </RESPONSE> Test passed! =)
          Hide
          Eloy Lafuente (stronk7) added a comment -

          Your nice code represents only 1/46 of the issues that have been sent upstream this week, so thanks, but not many.

          Nah, joking, many thanks! Closing this a fixed, ciao

          Show
          Eloy Lafuente (stronk7) added a comment - Your nice code represents only 1/46 of the issues that have been sent upstream this week, so thanks, but not many. Nah, joking, many thanks! Closing this a fixed, ciao

            People

            • Votes:
              0 Vote for this issue
              Watchers:
              3 Start watching this issue

              Dates

              • Created:
                Updated:
                Resolved: