public FluentResults.Result <(INode, bool)> Upsert(string predicate, GraphValue value, int maxRetrys = 1)
{
AssertNotDisposed();
var query = $"{{ q(func: eq({predicate}, \"{value.ToString()}\")) {{ uid }} }}";
var newNodeBlankName = "upsertNode";
var retryRemaining = (maxRetrys < 1) ? 1 : maxRetrys;
FluentResults.Result <(INode, bool)> result = null;
Func <FluentResults.Result <(INode, bool)>, FluentResults.Result <(INode, bool)>, FluentResults.Result <(INode, bool)> > addErr =
(FluentResults.Result <(INode, bool)> curError, FluentResults.Result <(INode, bool)> newError) => {
return(curError == null || !curError.IsFailed
? newError
: Results.Merge <(INode, bool)>(curError, newError));
};
while (retryRemaining >= 0)
{
retryRemaining--;
using (var txn = NewTransaction()) {
var queryResult = txn.Query(query);
if (queryResult.IsFailed)
{
result = addErr(result, queryResult.ConvertToResultWithValueType <(INode, bool)>());
continue;
}
if (String.Equals(queryResult.Value, "{\"q\":[]}", StringComparison.Ordinal))
{
var assigned = txn.Mutate($"{{ \"uid\": \"_:{newNodeBlankName}\", \"{predicate}\": \"{value.ToString()}\" }}");
if (assigned.IsFailed)
{
result = addErr(result, assigned.ConvertToResultWithValueType <(INode, bool)>());
continue;
}
var err = txn.Commit();
if (err.IsSuccess)
{
var UIDasString = assigned.Value[newNodeBlankName].Replace("0x", string.Empty); // why doesn't UInt64.TryParse() work with 0x...???
if (UInt64.TryParse(UIDasString, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var UID))
{
return(Results.Ok <(INode, bool)>((new UIDNode(UID), false)));
}
result = addErr(result, Results.Fail <(INode, bool)>("Failed to parse UID : " + UIDasString));
continue;
}
result = addErr(result, err.ConvertToResultWithValueType <(INode, bool)>());
continue;
}
else
{
var UIDasString = queryResult.Value
.Replace("{\"q\":[{\"uid\":\"0x", string.Empty)
.Replace("\"}]}", string.Empty);
if (UInt64.TryParse(UIDasString, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var UID))
{
return(Results.Ok <(INode, bool)>((new UIDNode(UID), true)));
}
result = addErr(result, Results.Fail <(INode, bool)>("Failed to parse UID : " + UIDasString));
continue;
}
}
}
return(result);
}
