User:Base/Scripts/RestoringPageHistory.js

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var api = new mw.Api();
var reason = prompt('Why would you want to undelete those again?', 'fehlerhafte Löschung rückgängig gemacht');

api.get({
    action: 'query',
    meta: 'tokens'
}).done(function (data) {
    console.log(data);
    var token = data.query.tokens.csrftoken;

    var timestamps = '';
    var i = 0;

    var attempt = function() {
        {
            api.get({
                action: 'query',
                prop: 'deletedrevisions',
                titles: mw.config.get('wgPageName'),
                drvlimit: 500
            }).done(function (drvdata) {
                console.log(drvdata);
                // -1 if completely deleted, otherwise it would be the respective page id
                timestamps = drvdata.query.pages[mw.config.get('wgArticleId')/*'-1'*/].deletedrevisions
                    .map(function (revision) {
                        return revision.timestamp;
                    });
                console.log(timestamps);
                console.log('Restoring #' + (++i) + ' batch');
                api.post({
                        action: 'undelete',
                        title: mw.config.get('wgPageName'),
                        reason: reason,
                        token: token,
                        timestamps: timestamps
                    },
                    {
                        contentType: 'multipart/form-data'
                    }
                ).done(function (data) {
                    console.log('Batch #' + i + ' must have been undeleted');
                    if(drvdata.continue){
                        attempt();
                    }
                })
            });
        }
    }
    attempt();
});