Some queries to wikimedia API are returning '' (empty string) values for the 'required' (boolean) field.
Examples:
{"title":"MobileWikiAppToCInteraction","description":"Track users as they interact with the ToC","properties":{"action":{"required":"","description":"Which action in the funnel this is representing","type":"string","enum":["open","close","click"]},"appInstallID":{"description":"AppInstallID that's unique to each app install and is used to track user across this and other features in the mobile app","type":"string","required":""}}}{"title":"MobileWikiAppArticleSuggestions","description":"Track when the user views or interacts with the 'read more' suggestions at the bottom of the current article.","properties":{"action":{"required":"","description":"Which user action triggered this event: 'shown' is used when the suggestions are first shown to the user, and 'clicked' is used when the user clicks one of the suggestions.","type":"string","enum":["shown","clicked"]},"appInstallID":{"description":"AppInstallID that's unique to each app install and is used to track user across this and other features in the mobile app","type":"string","required":""},"pageTitle":{"description":"Title of the page currently being viewed","type":"string","required":""},"readMoreList":{"description":"List of page suggestions displayed to the user (separated by a pipe symbol)","type":"string","required":""},"readMoreIndex":{"description":"Index of the suggested page that was clicked (only used with action=clicked)","type":"integer"},"version":{"description":"Revision of the Read More functionality that was presented to the user. Allowed values are:\n0: Old 'Read More' section with three items.\n1: New 'Read Next' section with a single item.","type":"integer","required":""}}}http://meta.wikimedia.org/w/api.php?action=jsonschema&title=ImageMetricsCorsSupport&revid=11686678
{"title":"ImageMetricsCorsSupport","description":"CORS support stats.","properties":{"xhrSupported":{"type":"boolean","required":"","description":"True if the browser supports CORS AJAX requests (with credentials - older, partial support is undetected)"},"xdomainSupported":{"type":"boolean","required":"","description":"True if the browser supports XDomainRequest (CORS replacement in old IE)"},"imgAttributeSupported":{"type":"boolean","required":"","description":"True if the browser supports the crossorigin attribute in an <img> tag"},"scriptAttributeSupported":{"type":"boolean","required":"","description":"True if the browser supports the crossorigin attribute in a <script> tag"},"scriptLoaded":{"type":"boolean","required":"","description":"True if the crossorigin script has been successfully loaded"},"sanityCheck":{"type":"boolean","required":"","description":"True if a normal script has been successfully loaded"},"country":{"type":"string","description":"Client's country (per geolocation)"},"isHttps":{"type":"boolean","required":"","description":"Whether the content was loaded over https or not"},"isAnon":{"type":"boolean","required":"","description":"Whether the user is logged in or not"},"samplingFactor":{"type":"integer","required":"","description":"Sampling factor"}}}This issue is breaking EventLogging, because the schema validator fails and terminates EL components.