using System;
using System.Globalization;
using System.Linq;
using System.Reflection;
using System.Web.Http.Controllers;
using System.Web.Http.Description;
using System.Xml.XPath;
namespace Authentication_test.Areas.HelpPage
{
///
/// A custom that reads the API documentation from an XML documentation file.
///
public class XmlDocumentationProvider : IDocumentationProvider
{
private XPathNavigator _documentNavigator;
private const string TypeExpression = "/doc/members/member[@name='T:{0}']";
private const string MethodExpression = "/doc/members/member[@name='M:{0}']";
private const string ParameterExpression = "param[@name='{0}']";
///
/// Initializes a new instance of the class.
///
/// The physical path to XML document.
public XmlDocumentationProvider(string documentPath)
{
if (documentPath == null)
{
throw new ArgumentNullException("documentPath");
}
XPathDocument xpath = new XPathDocument(documentPath);
_documentNavigator = xpath.CreateNavigator();
}
public string GetDocumentation(HttpControllerDescriptor controllerDescriptor)
{
XPathNavigator typeNode = GetTypeNode(controllerDescriptor);
return GetTagValue(typeNode, "summary");
}
public virtual string GetDocumentation(HttpActionDescriptor actionDescriptor)
{
XPathNavigator methodNode = GetMethodNode(actionDescriptor);
return GetTagValue(methodNode, "summary");
}
public virtual string GetDocumentation(HttpParameterDescriptor parameterDescriptor)
{
ReflectedHttpParameterDescriptor reflectedParameterDescriptor = parameterDescriptor as ReflectedHttpParameterDescriptor;
if (reflectedParameterDescriptor != null)
{
XPathNavigator methodNode = GetMethodNode(reflectedParameterDescriptor.ActionDescriptor);
if (methodNode != null)
{
string parameterName = reflectedParameterDescriptor.ParameterInfo.Name;
XPathNavigator parameterNode = methodNode.SelectSingleNode(String.Format(CultureInfo.InvariantCulture, ParameterExpression, parameterName));
if (parameterNode != null)
{
return parameterNode.Value.Trim();
}
}
}
return null;
}
public string GetResponseDocumentation(HttpActionDescriptor actionDescriptor)
{
XPathNavigator methodNode = GetMethodNode(actionDescriptor);
return GetTagValue(methodNode, "returns");
}
private XPathNavigator GetMethodNode(HttpActionDescriptor actionDescriptor)
{
ReflectedHttpActionDescriptor reflectedActionDescriptor = actionDescriptor as ReflectedHttpActionDescriptor;
if (reflectedActionDescriptor != null)
{
string selectExpression = String.Format(CultureInfo.InvariantCulture, MethodExpression, GetMemberName(reflectedActionDescriptor.MethodInfo));
return _documentNavigator.SelectSingleNode(selectExpression);
}
return null;
}
private static string GetMemberName(MethodInfo method)
{
string name = String.Format(CultureInfo.InvariantCulture, "{0}.{1}", method.DeclaringType.FullName, method.Name);
ParameterInfo[] parameters = method.GetParameters();
if (parameters.Length != 0)
{
string[] parameterTypeNames = parameters.Select(param => GetTypeName(param.ParameterType)).ToArray();
name += String.Format(CultureInfo.InvariantCulture, "({0})", String.Join(",", parameterTypeNames));
}
return name;
}
private static string GetTagValue(XPathNavigator parentNode, string tagName)
{
if (parentNode != null)
{
XPathNavigator node = parentNode.SelectSingleNode(tagName);
if (node != null)
{
return node.Value.Trim();
}
}
return null;
}
private static string GetTypeName(Type type)
{
if (type.IsGenericType)
{
// Format the generic type name to something like: Generic{System.Int32,System.String}
Type genericType = type.GetGenericTypeDefinition();
Type[] genericArguments = type.GetGenericArguments();
string typeName = genericType.FullName;
// Trim the generic parameter counts from the name
typeName = typeName.Substring(0, typeName.IndexOf('`'));
string[] argumentTypeNames = genericArguments.Select(t => GetTypeName(t)).ToArray();
return String.Format(CultureInfo.InvariantCulture, "{0}{{{1}}}", typeName, String.Join(",", argumentTypeNames));
}
return type.FullName;
}
private XPathNavigator GetTypeNode(HttpControllerDescriptor controllerDescriptor)
{
Type controllerType = controllerDescriptor.ControllerType;
string controllerTypeName = controllerType.FullName;
if (controllerType.IsNested)
{
// Changing the nested type name from OuterType+InnerType to OuterType.InnerType to match the XML documentation syntax.
controllerTypeName = controllerTypeName.Replace("+", ".");
}
string selectExpression = String.Format(CultureInfo.InvariantCulture, TypeExpression, controllerTypeName);
return _documentNavigator.SelectSingleNode(selectExpression);
}
}
}