/**
* @param chainrSpec Plain vanilla hydrated JSON representation of a Chainr spec .json file.
*/
public ChainrSpec(JToken chainrSpec, IReadOnlyDictionary <string, Type> transforms)
{
if (!(chainrSpec is JArray operations))
{
throw new SpecException("JOLT Chainr expects a JSON array of objects - Malformed spec.");
}
if (operations.Count == 0)
{
throw new SpecException("JOLT Chainr passed an empty JSON array.");
}
var entries = new List <ChainrEntry>(operations.Count);
for (int index = 0; index < operations.Count; index++)
{
var chainrEntryObj = operations[index];
ChainrEntry entry = new ChainrEntry(index, chainrEntryObj, transforms);
entries.Add(entry);
}
_chainrEntries = entries.AsReadOnly();
}
public IJoltTransform HydrateTransform(ChainrEntry entry)
{
var spec = entry.GetSpec();
Type transformType = entry.GetJoltTransformType();
try
{
// If the transform class is a SpecTransform, we try to construct it with the provided spec.
if (entry.IsSpecDriven())
{
// Lookup a Constructor with a Single "object" arg.
var constructor = transformType.GetConstructor(new[] { typeof(JObject) });
if (constructor == null)
{
// This means the transform class "violated" the SpecTransform marker interface
throw new SpecException("JOLT Chainr encountered an constructing SpecTransform className:" + transformType.Name +
". Specifically, no single arg constructor found" + entry.GetErrorMessageIndexSuffix());
}
return((IJoltTransform)constructor.Invoke(new object[] { spec }));
}
else
{
// The opClass is just a Transform, so just create a newInstance of it.
var constructor = transformType.GetConstructor(new Type[0]);
if (constructor == null)
{
throw new Exception("JOLT Chainr encountered an error constructing className:" + transformType.Name +
". Specifically, a no arg constructor was not found" + entry.GetErrorMessageIndexSuffix());
}
return((IJoltTransform)constructor.Invoke(new object[0]));
}
}
catch (Exception e)
{
// FYI 3 exceptions are known to be thrown here
// IllegalAccessException, InvocationTargetException, InstantiationException
throw new SpecException("JOLT Chainr encountered an exception constructing Transform className:"
+ transformType.Name + entry.GetErrorMessageIndexSuffix(), e);
}
}