/// <summary>
/// Adds an entry to the map.
/// Note that the new <paramref name="value"/> will be merged with existing values
/// on other nodes and the outcome depends on what <see cref="IReplicatedData"/>
/// type that is used.
///
/// Consider using <see cref="AddOrUpdate(Akka.Cluster.Cluster, TKey, TValue, Func{TValue, TValue})">AddOrUpdate</see> instead of <see cref="SetItem(UniqueAddress,TKey,TValue)"/> if you want modify
/// existing entry.
///
/// <see cref="ArgumentException"/> is thrown if you try to replace an existing <see cref="ORSet{T}"/>
/// value, because important history can be lost when replacing the `ORSet` and
/// undesired effects of merging will occur. Use <see cref="ORMultiValueDictionary{TKey,TValue}"/> or <see cref="AddOrUpdate(Akka.Cluster.Cluster, TKey, TValue, Func{TValue, TValue})">AddOrUpdate</see> instead.
/// </summary>
public ORDictionary <TKey, TValue> SetItem(UniqueAddress node, TKey key, TValue value)
{
if (value is IORSet && ValueMap.ContainsKey(key))
{
throw new ArgumentException("ORDictionary.SetItems may not be used to replace an existing ORSet", nameof(value));
}
var newKeys = KeySet.ResetDelta().Add(node, key);
var delta = new PutDeltaOperation(newKeys.Delta, key, value);
// put forcibly damages history, so we propagate full value that will overwrite previous values
return(new ORDictionary <TKey, TValue>(newKeys, ValueMap.SetItem(key, value), NewDelta(delta)));
}
internal ORDictionary <TKey, TValue> AddOrUpdate(UniqueAddress node, TKey key, TValue initial, bool valueDeltas,
Func <TValue, TValue> modify)
{
bool hasOldValue;
if (!ValueMap.TryGetValue(key, out var oldValue))
{
oldValue = initial;
hasOldValue = false;
}
else
{
hasOldValue = true;
}
// Optimization: for some types - like GSet, GCounter, PNCounter and ORSet - that are delta based
// we can emit (and later merge) their deltas instead of full updates.
// However to avoid necessity of tombstones, the derived map type needs to support this
// with clearing the value (e.g. removing all elements if value is a set)
// before removing the key - like e.g. ORMultiMap does
var newKeys = KeySet.ResetDelta().Add(node, key);
if (valueDeltas && oldValue is IDeltaReplicatedData deltaOldValue)
{
var newValue = modify((TValue)deltaOldValue.ResetDelta());
var newValueDelta = ((IDeltaReplicatedData)newValue).Delta;
if (newValueDelta != null && hasOldValue)
{
var op = new UpdateDeltaOperation(newKeys.Delta, ImmutableDictionary.CreateRange(new[] { new KeyValuePair <TKey, IReplicatedData>(key, newValueDelta) }));
return(new ORDictionary <TKey, TValue>(newKeys, ValueMap.SetItem(key, newValue), NewDelta(op)));
}
else
{
var op = new PutDeltaOperation(newKeys.Delta, key, newValue);
return(new ORDictionary <TKey, TValue>(newKeys, ValueMap.SetItem(key, newValue), NewDelta(op)));
}
}
else
{
var newValue = modify(oldValue);
var delta = new PutDeltaOperation(newKeys.Delta, key, newValue);
return(new ORDictionary <TKey, TValue>(newKeys, ValueMap.SetItem(key, newValue), NewDelta(delta)));
}
}
