Parse Installation deduplication - Cloud Code

parse-installation-cloud-code.js

Parse.Cloud.beforeSave(Parse.Installation, function(request, response) {
    var androidId = request.object.get("androidId");
    if (!androidId) {
        console.warn("No androidId found, save and exit");
        return response.success();
    }
    
    var query = new Parse.Query(Parse.Installation);
    query.equalTo("androidId", androidId);
    query.ascending("createdAt");
    query.find()
      .then(results => {
          return results.map(r => r.destroy());
      })
      .then(() => response.success())
      .catch(err => response.error("Error: Can't query for Installation objects."));
});