///////////////////////////////////////////////////////////////////////
#region Private Members
private void Vote(
PolicyDecision decision
)
{
switch (decision)
{
case PolicyDecision.Undecided:
{
Interlocked.Increment(ref undecidedCount);
break;
}
case PolicyDecision.Denied:
{
Interlocked.Increment(ref deniedCount);
break;
}
case PolicyDecision.Approved:
{
Interlocked.Increment(ref approvedCount);
break;
}
}
}
protected override PolicyDecision <ActionProbability[]> MapContext(VowpalWabbit vw, string context)
{
using (var vwJson = new VowpalWabbitJsonSerializer(vw))
using (VowpalWabbitExampleCollection vwExample = vwJson.ParseAndCreate(context))
{
if (this.developmentMode)
{
Trace.TraceInformation("Example Context: '{0}'", vwExample.VowpalWabbitString);
}
var vwPredictions = vwExample.Predict(VowpalWabbitPredictionType.ActionProbabilities);
// VW multi-label predictions are 0-based
var ap = vwPredictions
.Select(a =>
new ActionProbability
{
Action = (int)(a.Action + 1),
Probability = a.Score
})
.ToArray();
var state = new VWState {
ModelId = vw.Native.ID
};
return(PolicyDecision.Create(ap, state));
}
}
protected override PolicyDecision <ActionProbability[]> MapContext(VowpalWabbit <TContext> vw, TContext context)
{
if (this.developmentMode)
{
using (var serializer = vw.Serializer.Create(vw.Native))
{
Trace.TraceInformation("Example Context: {0}", serializer.SerializeToString(context));
}
}
var vwPredictions = vw.Predict(context, VowpalWabbitPredictionType.ActionProbabilities);
// VW multi-label predictions are 0-based
var ap = vwPredictions
.Select(a =>
new ActionProbability
{
Action = (int)(a.Action + 1),
Probability = a.Score
})
.ToArray();
var state = new VWState {
ModelId = vw.Native.ID
};
return(PolicyDecision.Create(ap, state));
}
public PolicyDecision <ActionProbability[]> MapContext(T context)
{
return(PolicyDecision.Create(Enumerable.Range(1, this.numActionsFunc(context))
.Select(a => new ActionProbability {
Action = a, Probability = a == 1 ? 1f : 0
})
.ToArray()));
}
public PolicyDecision GetPolicyDecision(IPrincipal principal, object securable)
{
var retVal = new PolicyDecision(securable, new System.Collections.Generic.List <PolicyDecisionDetail>()
{
new PolicyDecisionDetail(PermissionPolicyIdentifiers.AccessAuditLog, PolicyGrantType.Grant)
});
return(retVal);
}
/// <summary>
/// Add policy authorization to the audit
/// </summary>
public static AuditData WithPolicyAuthorization(this AuditData me, PolicyDecision policy)
{
me.AuditableObjects.AddRange(policy.Details.Select(o => new AuditableObject()
{
IDTypeCode = AuditableObjectIdType.Uri,
Role = AuditableObjectRole.SecurityGranularityDefinition,
Type = AuditableObjectType.SystemObject,
LifecycleType = AuditableObjectLifecycle.Verification,
ObjectId = o.PolicyId
}));
return(me);
}
/// <summary>
/// Determines the action to take for a given context.
/// This implementation should be thread-safe if multithreading is needed.
/// </summary>
/// <param name="vw">The Vowpal Wabbit instance to use.</param>
/// <param name="context">A user-defined context for the decision.</param>
/// <returns>A decision tuple containing the index of the action to take (1-based), and the Id of the model or policy used to make the decision.
/// Can be null if the Policy is not ready yet (e.g. model not loaded).</returns>
protected override PolicyDecision <int> MapContext(VowpalWabbit vw, string context)
{
using (var vwJson = new VowpalWabbitJsonSerializer(vw))
using (VowpalWabbitExampleCollection vwExample = vwJson.ParseAndCreate(context))
{
var action = (int)vwExample.Predict(VowpalWabbitPredictionType.CostSensitive);
var state = new VWState {
ModelId = vw.ID
};
return(PolicyDecision.Create(action, state));
}
}
/// <summary>
/// Determines the action to take for a given context.
/// This implementation should be thread-safe if multithreading is needed.
/// </summary>
/// <param name="vw">The Vowpal Wabbit instance to use.</param>
/// <param name="context">A user-defined context for the decision.</param>
/// <returns>A decision tuple containing the index of the action to take (1-based), and the Id of the model or policy used to make the decision.
/// Can be null if the Policy is not ready yet (e.g. model not loaded).</returns>
protected override PolicyDecision <int[]> MapContext(VowpalWabbit vw, string context)
{
using (var vwJson = new VowpalWabbitJsonSerializer(vw))
using (VowpalWabbitExampleCollection vwExample = vwJson.ParseAndCreate(context))
{
ActionScore[] vwMultilabelPredictions = vwExample.Predict(VowpalWabbitPredictionType.ActionProbabilities);
// VW multi-label predictions are 0-based
var actions = vwMultilabelPredictions.Select(a => (int)a.Action + 1).ToArray();
var state = new VWState {
ModelId = vw.ID
};
return(PolicyDecision.Create(actions, state));
}
}
protected override PolicyDecision <int> MapContext(VowpalWabbit <TContext> vw, TContext context)
{
if (this.developmentMode)
{
using (var serializer = vw.Serializer.Create(vw.Native))
{
Trace.TraceInformation("Example Context: {0}", serializer.SerializeToString(context));
}
}
var action = (int)vw.Predict(context, VowpalWabbitPredictionType.CostSensitive);
var state = new VWState {
ModelId = vw.Native.ID
};
return(PolicyDecision.Create(action, state));
}
///////////////////////////////////////////////////////////////////////
private PolicyContext(
PolicyFlags flags,
AssemblyName assemblyName,
string typeName,
IExecute execute,
ArgumentList arguments,
IScript script,
string fileName,
byte[] bytes,
string text,
Encoding encoding,
byte[] hashValue,
string hashAlgorithmName,
IClientData clientData,
IPlugin plugin,
PolicyDecision originalDecision
)
: this()
{
this.flags = flags;
this.assemblyName = assemblyName;
this.typeName = typeName;
this.execute = execute;
this.arguments = arguments;
this.script = script;
this.fileName = fileName;
this.bytes = bytes;
this.text = text;
this.encoding = encoding;
this.hashValue = hashValue;
this.hashAlgorithmName = hashAlgorithmName;
this.clientData = clientData;
this.plugin = plugin;
this.originalDecision = originalDecision;
//
// NOTE: *WARNING* Take the original decision into account. With
// the current logic, if the original decision is "denied"
// then any later votes do not matter.
//
Vote(this.originalDecision);
}
protected override PolicyDecision <int[]> MapContext(VowpalWabbit <TContext> vw, TContext context)
{
if (this.developmentMode)
{
using (var serializer = vw.Serializer.Create(vw.Native))
{
Trace.TraceInformation("Example Context: {0}", serializer.SerializeToString(context));
}
}
ActionScore[] vwMultilabelPredictions = vw.Predict(context, VowpalWabbitPredictionType.ActionScore);
// VW multi-label predictions are 0-based
var actions = vwMultilabelPredictions.Select(a => (int)a.Action + 1).ToArray();
var state = new VWState {
ModelId = vw.Native.ID
};
return(PolicyDecision.Create(actions, state));
}
protected override bool OnDecidePolicy(PolicyDecision decision, PolicyDecisionType decision_type)
{
if (decision_type != PolicyDecisionType.NavigationAction)
{
decision.Use();
return(false);
}
string uri = (decision as NavigationPolicyDecision).Request.Uri;
if (uri.Equals("file:///"))
{
decision.Use();
return(false);
}
LinkClicked(uri);
decision.Ignore();
return(true);
}
///////////////////////////////////////////////////////////////////////
#region Static "Factory" Members
public static PolicyContext Create(
PolicyFlags flags,
AssemblyName assemblyName,
string typeName,
IExecute execute,
ArgumentList arguments,
IScript script,
string fileName,
byte[] bytes,
string text,
Encoding encoding,
byte[] hashValue,
string hashAlgorithmName,
IClientData clientData,
IPlugin plugin,
PolicyDecision originalDecision
)
{
return(new PolicyContext(
flags, assemblyName, typeName, execute, arguments, script,
fileName, bytes, text, encoding, hashValue, hashAlgorithmName,
clientData, plugin, originalDecision));
}
protected override bool OnDecidePolicy (PolicyDecision decision, PolicyDecisionType decision_type)
{
if (decision_type != PolicyDecisionType.NavigationAction) {
decision.Use ();
return false;
}
string uri = (decision as NavigationPolicyDecision).Request.Uri;
if (uri.Equals ("file:///")) {
decision.Use ();
return false;
}
LinkClicked (uri);
decision.Ignore ();
return true;
}
///////////////////////////////////////////////////////////////////////
public static bool IsDenied(
PolicyDecision decision
)
{
return(decision == PolicyDecision.Denied);
}
PolicyDecision <int> IContextMapper <UserContext, int> .MapContext(UserContext context)
{
int chosenAction = (int)Math.Round(context.Features.Sum(f => f.Value) / context.Features.Count + 1);
return(PolicyDecision.Create(chosenAction));
}
///////////////////////////////////////////////////////////////////////
public static bool IsApproved(
PolicyDecision decision
)
{
return(decision == PolicyDecision.Approved);
}
///////////////////////////////////////////////////////////////////////
public static bool IsUndecided(
PolicyDecision decision
)
{
return(decision == PolicyDecision.Undecided);
}
/// <summary>
/// Initializes a new instance of the <see cref="PolicyViolationException"/> class.
/// </summary>
/// <param name="principal">The principal which attempted the action</param>
/// <param name="decision">The decision of the policy which caused the exception</param>
public PolicyViolationException(IPrincipal principal, PolicyDecision decision)
{
this.PolicyId = decision.Details.First(p => p.Outcome == decision.Outcome).PolicyId;
this.Detail = decision;
this.PolicyDecision = principal.Identity.Name == "ANONYMOUS" ? PolicyGrantType.Elevate : decision.Outcome;
}
public Task <PolicyDecision <int[]> > MapContextAsync(int[] context)
{
return(Task.FromResult(PolicyDecision.Create(context)));
}
///////////////////////////////////////////////////////////////////////
public static bool IsNone(
PolicyDecision decision
)
{
return(decision == PolicyDecision.None);
}