private async Task FetchStackFramesAndVariablesAsync(string scriptNameOverride)
{
await debugInfoHandle.WaitAsync().ConfigureAwait(false);
try
{
nextVariableId = VariableDetailsBase.FirstVariableId;
variables = new List <VariableDetailsBase>
{
// Create a dummy variable for index 0, should never see this.
new VariableDetails("Dummy", null)
};
// Must retrieve in order of broadest to narrowest scope for efficient
// deduplication: global, script, local.
globalScopeVariables = await FetchVariableContainerAsync(VariableContainerDetails.GlobalScopeName).ConfigureAwait(false);
scriptScopeVariables = await FetchVariableContainerAsync(VariableContainerDetails.ScriptScopeName).ConfigureAwait(false);
localScopeVariables = await FetchVariableContainerAsync(VariableContainerDetails.LocalScopeName).ConfigureAwait(false);
await FetchStackFramesAsync(scriptNameOverride).ConfigureAwait(false);
}
finally
{
debugInfoHandle.Release();
}
}
private async Task FetchGlobalAndScriptVariablesAsync()
{
// Retrieve globals first as script variable retrieval needs to search globals.
this.globalScopeVariables =
await FetchVariableContainerAsync(VariableContainerDetails.GlobalScopeName, null).ConfigureAwait(false);
this.scriptScopeVariables =
await FetchVariableContainerAsync(VariableContainerDetails.ScriptScopeName, null).ConfigureAwait(false);
}
private async Task FetchStackFramesAsync(string scriptNameOverride)
{
PSCommand psCommand = new PSCommand();
// This glorious hack ensures that Get-PSCallStack returns a list of CallStackFrame
// objects (or "deserialized" CallStackFrames) when attached to a runspace in another
// process. Without the intermediate variable Get-PSCallStack inexplicably returns
// an array of strings containing the formatted output of the CallStackFrame list.
var callStackVarName = $"$global:{PsesGlobalVariableNamePrefix}CallStack";
psCommand.AddScript($"{callStackVarName} = Get-PSCallStack; {callStackVarName}");
var results = await this.powerShellContext.ExecuteCommandAsync <PSObject>(psCommand).ConfigureAwait(false);
var callStackFrames = results.ToArray();
this.stackFrameDetails = new StackFrameDetails[callStackFrames.Length];
for (int i = 0; i < callStackFrames.Length; i++)
{
VariableContainerDetails autoVariables =
new VariableContainerDetails(
this.nextVariableId++,
VariableContainerDetails.AutoVariablesName);
this.variables.Add(autoVariables);
VariableContainerDetails localVariables =
await FetchVariableContainerAsync(i.ToString(), autoVariables).ConfigureAwait(false);
// When debugging, this is the best way I can find to get what is likely the workspace root.
// This is controlled by the "cwd:" setting in the launch config.
string workspaceRootPath = this.powerShellContext.InitialWorkingDirectory;
this.stackFrameDetails[i] =
StackFrameDetails.Create(callStackFrames[i], autoVariables, localVariables, workspaceRootPath);
string stackFrameScriptPath = this.stackFrameDetails[i].ScriptPath;
if (scriptNameOverride != null &&
string.Equals(stackFrameScriptPath, StackFrameDetails.NoFileScriptPath))
{
this.stackFrameDetails[i].ScriptPath = scriptNameOverride;
}
else if (this.powerShellContext.CurrentRunspace.Location == RunspaceLocation.Remote &&
this.remoteFileManager != null &&
!string.Equals(stackFrameScriptPath, StackFrameDetails.NoFileScriptPath))
{
this.stackFrameDetails[i].ScriptPath =
this.remoteFileManager.GetMappedPath(
stackFrameScriptPath,
this.powerShellContext.CurrentRunspace);
}
}
}
private async Task <VariableContainerDetails> FetchVariableContainerAsync(
string scope,
VariableContainerDetails autoVariables)
{
PSCommand psCommand = new PSCommand();
psCommand.AddCommand("Get-Variable");
psCommand.AddParameter("Scope", scope);
var scopeVariableContainer =
new VariableContainerDetails(this.nextVariableId++, "Scope: " + scope);
this.variables.Add(scopeVariableContainer);
var results = await this.powerShellContext.ExecuteCommandAsync <PSObject>(psCommand, sendErrorToHost : false).ConfigureAwait(false);
if (results != null)
{
foreach (PSObject psVariableObject in results)
{
var variableDetails = new VariableDetails(psVariableObject)
{
Id = this.nextVariableId++
};
this.variables.Add(variableDetails);
scopeVariableContainer.Children.Add(variableDetails.Name, variableDetails);
if ((autoVariables != null) && AddToAutoVariables(psVariableObject, scope))
{
autoVariables.Children.Add(variableDetails.Name, variableDetails);
}
}
}
return(scopeVariableContainer);
}
/// <summary>
/// Sets the specified variable by container variableReferenceId and variable name to the
/// specified new value. If the variable cannot be set or converted to that value this
/// method will throw InvalidPowerShellExpressionException, ArgumentTransformationMetadataException, or
/// SessionStateUnauthorizedAccessException.
/// </summary>
/// <param name="variableContainerReferenceId">The container (Autos, Local, Script, Global) that holds the variable.</param>
/// <param name="name">The name of the variable prefixed with $.</param>
/// <param name="value">The new string value. This value must not be null. If you want to set the variable to $null
/// pass in the string "$null".</param>
/// <returns>The string representation of the value the variable was set to.</returns>
/// <exception cref="InvalidPowerShellExpressionException"></exception>
public async Task <string> SetVariableAsync(int variableContainerReferenceId, string name, string value)
{
Validate.IsNotNull(nameof(name), name);
Validate.IsNotNull(nameof(value), value);
_logger.LogTrace($"SetVariableRequest for '{name}' to value string (pre-quote processing): '{value}'");
// An empty or whitespace only value is not a valid expression for SetVariable.
if (value.Trim().Length == 0)
{
throw new InvalidPowerShellExpressionException("Expected an expression.");
}
// Evaluate the expression to get back a PowerShell object from the expression string.
// This may throw, in which case the exception is propagated to the caller
PSCommand evaluateExpressionCommand = new PSCommand().AddScript(value);
IReadOnlyList <object> expressionResults = await _executionService.ExecutePSCommandAsync <object>(evaluateExpressionCommand, CancellationToken.None).ConfigureAwait(false);
if (expressionResults.Count == 0)
{
throw new InvalidPowerShellExpressionException("Expected an expression result.");
}
object expressionResult = expressionResults[0];
// If PowerShellContext.ExecuteCommand returns an ErrorRecord as output, the expression failed evaluation.
// Ideally we would have a separate means from communicating error records apart from normal output.
if (expressionResult is ErrorRecord errorRecord)
{
throw new InvalidPowerShellExpressionException(errorRecord.ToString());
}
// OK, now we have a PS object from the supplied value string (expression) to assign to a variable.
// Get the variable referenced by variableContainerReferenceId and variable name.
VariableContainerDetails variableContainer = null;
await debugInfoHandle.WaitAsync().ConfigureAwait(false);
try
{
variableContainer = (VariableContainerDetails)variables[variableContainerReferenceId];
}
finally
{
debugInfoHandle.Release();
}
VariableDetailsBase variable = variableContainer.Children[name];
// Determine scope in which the variable lives so we can pass it to `Get-Variable
// -Scope`. The default is scope 0 which is safe because if a user is able to see a
// variable in the debugger and so change it through this interface, it's either in the
// top-most scope or in one of the following named scopes. The default scope is most
// likely in the case of changing from the "auto variables" container.
string scope = "0";
// NOTE: This can't use a switch because the IDs aren't constant.
if (variableContainerReferenceId == localScopeVariables.Id)
{
scope = VariableContainerDetails.LocalScopeName;
}
else if (variableContainerReferenceId == scriptScopeVariables.Id)
{
scope = VariableContainerDetails.ScriptScopeName;
}
else if (variableContainerReferenceId == globalScopeVariables.Id)
{
scope = VariableContainerDetails.GlobalScopeName;
}
// Now that we have the scope, get the associated PSVariable object for the variable to be set.
PSCommand getVariableCommand = new PSCommand()
.AddCommand(@"Microsoft.PowerShell.Utility\Get-Variable")
.AddParameter("Name", name.TrimStart('$'))
.AddParameter("Scope", scope);
IReadOnlyList <PSVariable> psVariables = await _executionService.ExecutePSCommandAsync <PSVariable>(getVariableCommand, CancellationToken.None).ConfigureAwait(false);
if (psVariables.Count == 0)
{
throw new Exception("Failed to retrieve PSVariables");
}
PSVariable psVariable = psVariables[0];
if (psVariable is null)
{
throw new Exception($"Failed to retrieve PSVariable object for '{name}' from scope '{scope}'.");
}
// We have the PSVariable object for the variable the user wants to set and an object to assign to that variable.
// The last step is to determine whether the PSVariable is "strongly typed" which may require a conversion.
// If it is not strongly typed, we simply assign the object directly to the PSVariable potentially changing its type.
// Turns out ArgumentTypeConverterAttribute is not public. So we call the attribute through it's base class -
// ArgumentTransformationAttribute.
ArgumentTransformationAttribute argTypeConverterAttr = null;
foreach (Attribute variableAttribute in psVariable.Attributes)
{
if (variableAttribute is ArgumentTransformationAttribute argTransformAttr &&
argTransformAttr.GetType().Name.Equals("ArgumentTypeConverterAttribute"))
{
argTypeConverterAttr = argTransformAttr;
break;
}
}
if (argTypeConverterAttr is not null)
{
// PSVariable *is* strongly typed, so we have to convert it.
_logger.LogTrace($"Setting variable '{name}' using conversion to value: {expressionResult ?? "<null>"}");
// NOTE: We use 'Get-Variable' here instead of 'SessionStateProxy.GetVariable()'
// because we already have a pipeline running (the debugger) and the latter cannot
// run concurrently (threw 'NoSessionStateProxyWhenPipelineInProgress').
IReadOnlyList <EngineIntrinsics> results = await _executionService.ExecutePSCommandAsync <EngineIntrinsics>(
new PSCommand()
.AddCommand(@"Microsoft.PowerShell.Utility\Get-Variable")
.AddParameter("Name", "ExecutionContext")
.AddParameter("ValueOnly"),
CancellationToken.None).ConfigureAwait(false);
EngineIntrinsics engineIntrinsics = results.Count > 0
? results[0]
: throw new Exception("Couldn't get EngineIntrinsics!");
// TODO: This is almost (but not quite) the same as 'LanguagePrimitives.Convert()',
// which does not require the pipeline thread. We should investigate changing it.
psVariable.Value = argTypeConverterAttr.Transform(engineIntrinsics, expressionResult);
}
else
{
// PSVariable is *not* strongly typed. In this case, whack the old value with the new value.
_logger.LogTrace($"Setting variable '{name}' directly to value: {expressionResult ?? "<null>"} - previous type was {psVariable.Value?.GetType().Name ?? "<unknown>"}");
psVariable.Value = expressionResult;
}
// Use the VariableDetails.ValueString functionality to get the string representation for client debugger.
// This makes the returned string consistent with the strings normally displayed for variables in the debugger.
VariableDetails tempVariable = new(psVariable);
_logger.LogTrace($"Set variable '{name}' to: {tempVariable.ValueString ?? "<null>"}");
return(tempVariable.ValueString);
}
/// <summary>
/// Sets the specified variable by container variableReferenceId and variable name to the
/// specified new value. If the variable cannot be set or converted to that value this
/// method will throw InvalidPowerShellExpressionException, ArgumentTransformationMetadataException, or
/// SessionStateUnauthorizedAccessException.
/// </summary>
/// <param name="variableContainerReferenceId">The container (Autos, Local, Script, Global) that holds the variable.</param>
/// <param name="name">The name of the variable prefixed with $.</param>
/// <param name="value">The new string value. This value must not be null. If you want to set the variable to $null
/// pass in the string "$null".</param>
/// <returns>The string representation of the value the variable was set to.</returns>
public async Task <string> SetVariableAsync(int variableContainerReferenceId, string name, string value)
{
Validate.IsNotNull(nameof(name), name);
Validate.IsNotNull(nameof(value), value);
this.logger.LogTrace($"SetVariableRequest for '{name}' to value string (pre-quote processing): '{value}'");
// An empty or whitespace only value is not a valid expression for SetVariable.
if (value.Trim().Length == 0)
{
throw new InvalidPowerShellExpressionException("Expected an expression.");
}
// Evaluate the expression to get back a PowerShell object from the expression string.
PSCommand psCommand = new PSCommand();
psCommand.AddScript(value);
var errorMessages = new StringBuilder();
var results =
await this.powerShellContext.ExecuteCommandAsync <object>(
psCommand,
errorMessages,
false,
false).ConfigureAwait(false);
// Check if PowerShell's evaluation of the expression resulted in an error.
object psobject = results.FirstOrDefault();
if ((psobject == null) && (errorMessages.Length > 0))
{
throw new InvalidPowerShellExpressionException(errorMessages.ToString());
}
// If PowerShellContext.ExecuteCommand returns an ErrorRecord as output, the expression failed evaluation.
// Ideally we would have a separate means from communicating error records apart from normal output.
if (psobject is ErrorRecord errorRecord)
{
throw new InvalidPowerShellExpressionException(errorRecord.ToString());
}
// OK, now we have a PS object from the supplied value string (expression) to assign to a variable.
// Get the variable referenced by variableContainerReferenceId and variable name.
VariableContainerDetails variableContainer = null;
await this.debugInfoHandle.WaitAsync().ConfigureAwait(false);
try
{
variableContainer = (VariableContainerDetails)this.variables[variableContainerReferenceId];
}
finally
{
this.debugInfoHandle.Release();
}
VariableDetailsBase variable = variableContainer.Children[name];
// Determine scope in which the variable lives. This is required later for the call to Get-Variable -Scope.
string scope = null;
if (variableContainerReferenceId == this.scriptScopeVariables.Id)
{
scope = "Script";
}
else if (variableContainerReferenceId == this.globalScopeVariables.Id)
{
scope = "Global";
}
else
{
// Determine which stackframe's local scope the variable is in.
StackFrameDetails[] stackFrames = await this.GetStackFramesAsync().ConfigureAwait(false);
for (int i = 0; i < stackFrames.Length; i++)
{
var stackFrame = stackFrames[i];
if (stackFrame.LocalVariables.ContainsVariable(variable.Id))
{
scope = i.ToString();
break;
}
}
}
if (scope == null)
{
// Hmm, this would be unexpected. No scope means do not pass GO, do not collect $200.
throw new Exception("Could not find the scope for this variable.");
}
// Now that we have the scope, get the associated PSVariable object for the variable to be set.
psCommand.Commands.Clear();
psCommand = new PSCommand();
psCommand.AddCommand(@"Microsoft.PowerShell.Utility\Get-Variable");
psCommand.AddParameter("Name", name.TrimStart('$'));
psCommand.AddParameter("Scope", scope);
IEnumerable <PSVariable> result = await this.powerShellContext.ExecuteCommandAsync <PSVariable>(psCommand, sendErrorToHost : false).ConfigureAwait(false);
PSVariable psVariable = result.FirstOrDefault();
if (psVariable == null)
{
throw new Exception($"Failed to retrieve PSVariable object for '{name}' from scope '{scope}'.");
}
// We have the PSVariable object for the variable the user wants to set and an object to assign to that variable.
// The last step is to determine whether the PSVariable is "strongly typed" which may require a conversion.
// If it is not strongly typed, we simply assign the object directly to the PSVariable potentially changing its type.
// Turns out ArgumentTypeConverterAttribute is not public. So we call the attribute through it's base class -
// ArgumentTransformationAttribute.
var argTypeConverterAttr =
psVariable.Attributes
.OfType <ArgumentTransformationAttribute>()
.FirstOrDefault(a => a.GetType().Name.Equals("ArgumentTypeConverterAttribute"));
if (argTypeConverterAttr != null)
{
// PSVariable is strongly typed. Need to apply the conversion/transform to the new value.
psCommand.Commands.Clear();
psCommand = new PSCommand();
psCommand.AddCommand(@"Microsoft.PowerShell.Utility\Get-Variable");
psCommand.AddParameter("Name", "ExecutionContext");
psCommand.AddParameter("ValueOnly");
errorMessages.Clear();
var getExecContextResults =
await this.powerShellContext.ExecuteCommandAsync <object>(
psCommand,
errorMessages,
sendErrorToHost : false).ConfigureAwait(false);
EngineIntrinsics executionContext = getExecContextResults.OfType <EngineIntrinsics>().FirstOrDefault();
var msg = $"Setting variable '{name}' using conversion to value: {psobject ?? "<null>"}";
this.logger.LogTrace(msg);
psVariable.Value = argTypeConverterAttr.Transform(executionContext, psobject);
}
else
{
// PSVariable is *not* strongly typed. In this case, whack the old value with the new value.
var msg = $"Setting variable '{name}' directly to value: {psobject ?? "<null>"} - previous type was {psVariable.Value?.GetType().Name ?? "<unknown>"}";
this.logger.LogTrace(msg);
psVariable.Value = psobject;
}
// Use the VariableDetails.ValueString functionality to get the string representation for client debugger.
// This makes the returned string consistent with the strings normally displayed for variables in the debugger.
var tempVariable = new VariableDetails(psVariable);
this.logger.LogTrace($"Set variable '{name}' to: {tempVariable.ValueString ?? "<null>"}");
return(tempVariable.ValueString);
}
