In https://lists.wikimedia.org/pipermail/mediawiki-api-announce/2018-November/000143.html @Anomie announced a change in the way the error codes will be handled. We need to update Pywikibot to handle that. Current function is at https://github.com/wikimedia/pywikibot/blob/master/pywikibot/data/api.py#L2072
Full email for reference:
Currently the codes for uncaught exceptions include the class name, for
example "internal_api_error_ReadOnlyError", or
"internal_api_error_DBQueryError", or possibly something like
"internal_api_error_MediaWiki\Namespace\FooBarException". As you can see in
that last example, that can get rather ugly and complicates recent attempts
to verify that all error codes use a restricted character set.
Thus, we are deprecating these error codes. In the future all such errors
will use the code "internal_api_error". The date for that change has not
yet been set.
If a client for some reason needs to see the class of the uncaught
exception, this is available in a new 'errorclass' data property in the API
error. This will be returned beginning in 1.33.0-wmf.8 or later, see
https://www.mediawiki.org/wiki/MediaWiki_1.33/Roadmap for a schedule. Note
that database errors will report the actual class, such as
"MediaWiki\rdbms\DBQueryError", rather than the old unprefixed name that
had been being maintained for backwards compatibility.
Clients relying on specific internal error codes or detecting internal
errors by looking for a "internal_api_error_" prefix should be updated to
recognize "internal_api_error" and to use 'errorclass' in preference to
using any class name that might be present in the error code.
In JSON format with errorformat=bc, an internal error might look something
like this:
{
"error": {
"code": "internal_api_error_InvalidArgumentException",
"info": "[61e9f71eedbe401f17d41dd2] Exception caught: Testing",
"errorclass": "InvalidArgumentException",
"trace": "InvalidArgumentException at ..."
},
"servedby": "hostname"}
With modern errorformats, it might look like this:
{
"errors": [
{
"code": "internal_api_error_InvalidArgumentException",
"text": "[61e9f71eedbe401f17d41dd2] Exception caught: Testing",
"data": {
"errorclass": "InvalidArgumentException"
}
}
],
"trace": "InvalidArgumentException at ...",
"servedby": "hostname"}