/// <summary>
/// Create a new template context containing the specified merge fields.
/// </summary>
/// <param name="mergeFields"></param>
/// <returns></returns>
protected override ILavaRenderContext OnCreateRenderContext()
{
// Create a new DotLiquid Context.
// Set the flag to rethrow exceptions generated by the DotLiquid framework, so they can be intercepted and handled as Lava errors.
var dotLiquidContext = new global::DotLiquid.Context(new List <Hash>(), new Hash(), new Hash(), rethrowErrors: true);
var context = new DotLiquidRenderContext(dotLiquidContext);
return(context);
}
/// <summary>
/// Render a specific instance of the block in the provided context.
/// </summary>
/// <param name="context"></param>
/// <param name="result"></param>
public override void Render(Context context, TextWriter result)
{
var lavaContext = new DotLiquidRenderContext(context);
var block = _lavaBlock as ILiquidFrameworkElementRenderer;
if (block == null)
{
throw new Exception("Block proxy cannot be rendered.");
}
// Call the renderer implemented by the wrapped Lava block.
block.Render(this, lavaContext, result, null);
}
/// <summary>
/// Translate a set of DotLiquid filter arguments to a set of arguments that are compatible with a Lava filter.
/// </summary>
private void GetLavaFilterCompatibleArguments(string filterName, List <object> args, ParameterInfo[] lavaFilterFunctionParams, Context dotLiquidContext)
{
// Unwrap proxy objects.
for (int i = 0; i < args.Count; i++)
{
if (args[i] is ILiquidFrameworkDataObjectProxy proxy)
{
args[i] = proxy.GetProxiedDataObject();
}
if (args[i] is DropProxy)
{
args[i] = (( DropProxy )args[i]).ConvertToValueType();
}
}
// Inject the render context if it is requested.
if (lavaFilterFunctionParams.Length > 0 && lavaFilterFunctionParams[0].ParameterType == typeof(ILavaRenderContext))
{
var renderContext = new DotLiquidRenderContext(dotLiquidContext);
InitializeRenderContext(renderContext);
args.Insert(0, renderContext);
}
// Add in any missing parameters with the default values defined for the filter method.
if (lavaFilterFunctionParams.Length > args.Count)
{
for (int i = args.Count; i < lavaFilterFunctionParams.Length; ++i)
{
if ((lavaFilterFunctionParams[i].Attributes & ParameterAttributes.HasDefault) != ParameterAttributes.HasDefault)
{
throw new LavaException("Error - Filter '{0}' does not have a default value for '{1}' and no value was supplied", filterName, lavaFilterFunctionParams[i].Name);
}
args.Add(lavaFilterFunctionParams[i].DefaultValue);
}
}
}
