How to avoid duplicate files using Parse?

Question

I noticed that every time I deployed my application to my phone, it duplicates the installation in parsing to receive push notifications. How can I avoid this when I reinstall the application?

Answer 1

After a week of research and trial and error, I finally found a working solution. Basically, for this you need to do two things:

• In your Android app: pass in a unique identifier when initializing and saving ParseInstallation. we will use ANDROID_ID .
• Parse Cloud Code:. Installation, , Installation. , .

---

:

• onCreate() :

  //First: get the ANDROID_ID
  String android_id = Settings.Secure.getString(this.getContentResolver(), Settings.Secure.ANDROID_ID);
  Parse.initialize(this, "APP_ID", "CLIENT_KEY");
  //Now: add ANDROID_ID value to your Installation before saving.
  ParseInstallation.getCurrentInstallation().put("androidId", android_id);
  ParseInstallation.getCurrentInstallation().saveInBackground();
  

• :

  Parse.Cloud.beforeSave(Parse.Installation, function(request, response) {
      Parse.Cloud.useMasterKey();
      var androidId = request.object.get("androidId");
      if (androidId == null || androidId == "") {
          console.warn("No androidId found, save and exit");
          response.success();
      }
      var query = new Parse.Query(Parse.Installation);
      query.equalTo("androidId", androidId);
      query.addAscending("createdAt");
      query.find().then(function(results) {
          for (var i = 0; i < results.length; ++i) {
              console.warn("iterating over Installations with androidId= "+ androidId);
              if (results[i].get("installationId") != request.object.get("installationId")) {
                  console.warn("Installation["+i+"] and the request have different installationId values. Try to delete. [installationId:" + results[i].get("installationId") + "]");
                  results[i].destroy().then(function() {
                      console.warn("Installation["+i+"] has been deleted");
                  },
                  function() {
                      console.warn("Error: Installation["+i+"] could not be deleted");
                  });
              } else {
                  console.warn("Installation["+i+"] and the request has the same installationId value. Ignore. [installationId:" + results[i].get("installationId") + "]");
              }
          }
          console.warn("Finished iterating over Installations. A new Installation will be saved now...");
          response.success();
      },
      function(error) {
          response.error("Error: Can't query for Installation objects.");
      });
  });
  

!

---

:

• Android. ANDROID_ID. - . , .
• , put("androidId", android_id); androidId Installation Parse App.

---

: [1], [2], [3]