Hi,

I'm very new to JSON, so I'm not sure if I've phrased the quest correctly, but what I'm trying to do is store my player inventory data as a JSON object which I then update in the cloud.

I've followed the tutorial How to do partial queries and updates to complex JSON document and that part is working fine, I can create the document and add/change data in the document, but what I can't figure out is how to delete and entry in the inventory.

To illustrate what I mean, here is the JSON string for my player inventory as return by the Query Inventory code in the above tutorial.

{
 "@class": ".LogEventResponse",
 "scriptData": {
  "data": [
   {
    "_id": "5874f3fd9a8e0504cb538049",
    "SLOT_0": {
     "name": "Crystal",
     "quantity": 56
    },
    "SLOT_1": {
     "name": "Coal",
     "quantity": 100
    },
    "SLOT_2": {
     "name": "Leather",
     "quantity": 25
    },
    "SLOT_3": {
     "Item Name": "Stone",
     "Quantity": "46"
    },
    "SLOT_4": {
     "Item Name": "Wood",
     "Quantity": "500"
    }
   }
  ]
 }
}

And what I'd like to be able to do is delete a complete slot entry without having to replace the entire document, for example if I delete Slot_4 the result would be this.

{
 "@class": ".LogEventResponse",
 "scriptData": {
  "data": [
   {
    "_id": "5874f3fd9a8e0504cb538049",
    "SLOT_0": {
     "name": "Crystal",
     "quantity": 56
    },
    "SLOT_1": {
     "name": "Coal",
     "quantity": 100
    },
    "SLOT_2": {
     "name": "Leather",
     "quantity": 25
    },
    "SLOT_3": {
     "Item Name": "Stone",
     "Quantity": "46"
    }
   }
  ]
 }
}

This is my code for updating the inventory

var playerInventory = Spark.runtimeCollection("player_inventory");

var slotIndex = Spark.data.INDEX;
var slot = "SLOT_" + slotIndex.toString() + "." + Spark.data.FIELD;

var inputValue = Spark.data.VAL;

var updateObject = {};
updateObject[slot] = inputValue;

//Now do the mongo update.
playerInventory.update(
  {"_id": Spark.getPlayer().getPlayerId()}, //Looks for a doc with the _id of the current player
  {"$set" : updateObject}, // Uses the $set mongo modifier to set value at a path
  true, // Create the document if it does not exist (upsert)
  false // This query will only affect a single object (multi)
);

Spark.setScriptData("data", slot + " new value = " + inputValue);

I've tried using the DropIndexByName function as so...

var playerInventory = Spark.runtimeCollection("player_inventory");

playerInventory.

var slotIndex = Spark.data.INDEX;
var slot = "SLOT_" + slotIndex.toString();

playerInventory.dropIndexByName(slot);

Spark.setScriptData("data", "Cleared contents of " + slot);

but I get an error 27 index not found with name [SLOT_0], so I guess I've misunderstood things somewhat.

I'd be very grateful if someone would be able to provide an example or some pointers as to how I would handle the cloud code for this.

Many thanks

Martin

I've just realised there is an extra line (line 2) in the last code example above, the actual code I'm using is...

var playerInventory = Spark.runtimeCollection("player_inventory");

var slotIndex = Spark.data.INDEX;
var slot = "SLOT_" + slotIndex.toString();

playerInventory.dropIndexByName(slot);

Spark.setScriptData("data", "Cleared contents of " + slot);

Hi Patrick,

thanks for replying. I understand the principal of what you're suggesting, however I'm very inexperienced with JSON (I'd never used it up until a couple of days ago), and I may still struggle to turn 'Manipulate the object variable values or keys by constructing a new object with the variables you want to keep, in this case maybe slots 1 and 2' into working cloud code. (if you were talking about a C# typed list or something similar instead it would be easy for me to do.

However, I'll try a few things and see if I can get my head around it, and if I get completely stuck I'll post here again for more help if you don't mind.

Thanks

Martin.

Hi again,

this is just to acknowledge your second post which I didn't see until after my last reply. I'll check out the unset command and see if I can get that working how I want.

Thanks again

Martin.

Hi again Patrick,

thanks for the example, whilst as you say it isn't the best way to approach it, in terms of my learning how to manipulate JSON it is still very useful to me.

But in the meantime I've achieved my goal using the unset function as you suggested, with this cloud code, the fact that it works leads me to assume I have taken the correct approach, however I'll be happy to be instructed otherwise.

var playerInventory = Spark.runtimeCollection("player_inventory");

var slotIndex = Spark.data.INDEX;
var slot = "SLOT_" + slotIndex.toString();

var inputValue = Spark.data.VALUE;

var updateObject = {};
updateObject[slot] = slot;

//Now do the mongo update.
playerInventory.update(
  {"_id": Spark.getPlayer().getPlayerId()}, //Looks for a doc with the _id of the current player
  {"$unset" : updateObject}, // Uses the $set mongo modifier to set value at a path
  true, // Create the document if it does not exist (upsert)
  false // This query will only affect a single object (multi)
);

Spark.setScriptData("data", "Cleared contents of " + slot);

 Many thanks for the fast and informative replies, very much appreciated.

Martin.

I've just noticed that I left the var inputValue = Spark.data.VALUE; in the code by accident.

Which raises another question, I don't appear to be able to edit my posts, is there a way to do that?