private static string FormatGraphQLValue(object value, int depth = 0)
{
// some types require recursion as they can't be directly
// converted. There is a maximum depth we're using to avoid stack
// overflow. For null values we just return an empty string.
if (value == null || depth > MAX_RECURSION_DEPTH)
{
return(@"");
}
// string is probably the most common one.
// for strings, we need to add " and escape quotes.
if (value is string)
{
string input = (string)value;
string output = string.Concat("\"", input.Replace("\"", "\\\""), "\"");
return(output);
}
// GUIDs are a special type of string
if (value is Guid)
{
Guid input = (Guid)value;
string output = string.Concat("\"", input.ToString(), "\"");
return(output);
}
// boolean are expected to be lower case.
if (value is bool?)
{
bool?input = (bool?)value;
if (input.HasValue)
{
string output = input.ToString().ToLowerInvariant();
return(output);
}
return("");
}
// boolean are expected to be lower case.
if (value is bool)
{
bool input = (bool)value;
string output = input.ToString().ToLowerInvariant();
return(output);
}
// DateTime values are expected to be in JSON format.
if (value is DateTime)
{
DateTime input = (DateTime)value;
string output = string.Concat("\"", input.ToString("yyyy-MM-ddTHH:MM:ss.sssZ"), "\"");
return(output);
}
// numbers can be directly converted using their internal to string.
if (value is ValueType)
{
if (value is byte ||
value is short ||
value is int ||
value is long ||
value is sbyte ||
value is ushort ||
value is uint ||
value is ulong ||
value is float ||
value is double ||
value is decimal)
{
string output = value.ToString();
return(output);
}
}
// enumerations can be directly converted. This only works if the
// enumeration in C# is named exactly as in the GraphQL API.
if (value is Enum)
{
string output = value.ToString();
return(output);
}
// for arrays we don't care about the array's child types as they
// will be handled by a recursive function
if (value is Array)
{
IEnumerable input = value as IEnumerable;
List <string> inputList = new List <string>();
foreach (object element in input)
{
string fValue = FormatGraphQLValue(element, depth + 1);
// exclude empty values (strings that are of length 0.
// note that if the parameter supplies an empty string,
// it will actually be '\"\"' that is returned by
// FormatGraphQLValue, so this still works
if (string.IsNullOrEmpty(fValue))
{
continue;
}
inputList.Add(fValue);
}
// create an output string. We don't need to handle the case
// where inputList length is 0 as string.Join does that for us.
string output = string.Concat(@"[", string.Join(@",", inputList), @"]");
return(output);
}
// for GraphQLParameters we also need to apply recursion. If the
// rest of the code is adhering to a standard, this should only be
// called once and the recursion is not needed.
if (value is GraphQLParameters)
{
GraphQLParameters input = (GraphQLParameters)value;
string output = string.Concat(@"{", input.ToString(), @"}");
return(output);
}
// here we format every remaining object type. We recursively
// include every property that has the JsonPath attribute defined.
PropertyInfo[] properties = JsonPath.GetJsonPathProperties(value);
if (properties.Length > 0)
{
List <string> inputList = new List <string>();
foreach (PropertyInfo property in properties)
{
// this will return the first attribute matching. We don't
// need to check for null as the properties list is already
// filtered for only properties with the JsonPath attribute.
JsonPath attr = JsonPath.GetJsonPathAttribute(property);
// try formatting the value. If it is null, we won't add it
// to the parameter list.
string fValue = FormatGraphQLValue(property.GetValue(value), depth + 1);
if (string.IsNullOrEmpty(fValue))
{
continue;
}
string element = string.Concat(attr.BasePath, @":", fValue);
inputList.Add(element);
}
// if there are no property values set, we consider this an
// empty parameter set and we return an empty string.
if (inputList.Count == 0)
{
return(@"");
}
string output = string.Concat(@"{", string.Join(@",", inputList), @"}");
return(output);
}
// Catch all. We should not reach this.
throw new NebException("unsupported object type supplied");
}
