public void AddToUserInventory(ItemSchema.ItemDBSchema item)
{
var queryRequest = new QueryRequest()
.Statement("SELECT meta(`FarmWorld`).id, * FROM `FarmWorld` WHERE userName=$1 AND uniqueName=$2")
.AddPositionalParameter(item.userName)
.AddPositionalParameter(item.uniqueName);
var result = _bucket.Query <dynamic>(queryRequest);
if (!result.Success)
{
throw new Exception(String.Format("AddToUserInventory initial queryRequest failed: {0}", result.Status));
}
if (result.Rows.Count > 1)
{
throw new Exception(String.Format("AddToUserInventory initial query returned more than 1 row for uuesr {0} item {1}", item.userName, item.uniqueName));
}
if (result.Rows.Count == 0) // TODO: Potential race here if 2 items are added at same time on an item that did not exist before.
{
var idResult = _bucket.Increment("UserItemInventoryCounter");
if (!idResult.Success)
{
Console.WriteLine("Failed to get next increment for UserItemInventoryCounter.");
return;
}
var document = new Document <dynamic>
{
Id = "item" + idResult.Value.ToString(),
Content = item
};
var upsert = _bucket.Upsert(document);
if (!upsert.Success)
{
throw new Exception(String.Format("Upserting item failed for user {0} and item {1} and quantity {2}", item.userName, item.uniqueName, item.quantity));
}
}
else
{
var row = result.Rows[0];
string id = row.GetValue("id");
var lockResult = _bucket.GetAndLock <dynamic>(id, 1); // TODO: Implement wait and retry.
if (!lockResult.Success)
{
if (lockResult.Status == Couchbase.IO.ResponseStatus.Locked)
{
Console.WriteLine(String.Format("Item with id {0} already DB locked for user {1}.", id, item.userName));
}
else if (lockResult.Status == Couchbase.IO.ResponseStatus.KeyNotFound)
{
throw new Exception(String.Format("Locking item failed for user {0} and item {1} and quantity {2}", item.userName, item.uniqueName, item.quantity));
}
else
{
throw new NotImplementedException(String.Format("Lock operation threw status {0} which is not handled on id {1}.", lockResult.Status, id));
}
}
Newtonsoft.Json.Linq.JObject obj = lockResult.Value;
obj["quantity"] = item.quantity + obj.Value <int>("quantity");
IOperationResult replaceResult = _bucket.Replace(id, obj, lockResult.Cas); // This replaces the object and releases the DB lock.
if (!replaceResult.Success)
{
throw new Exception(String.Format("Replace on item id '{0}' did not work: {1}.", id, replaceResult.Status));
}
}
}
