Allow reflection to find type in loaded assembly

[rmshaffer]

Two changes to QuantumMachineFactory here, to address issues I found while consuming this from IQ#:

• Take an IWorkspace parameter instead of a Workspace parameter.
• Load the type directly from the already-loaded assembly with the expected name, rather than using Type.GetType(), which seems to sometimes require an AssemblyQualifiedName including version number and public key token in order to load the type successfully. (Open to suggestions here, in case there's a simpler way of doing this, but this seems to work.)

[bamarsha]

When I try to create an IonQ machine, I get this:

Unhandled exception: System.InvalidOperationException: Sequence contains no matching element
   at System.Linq.ThrowHelper.ThrowNoMatchException()
   at System.Linq.Enumerable.First[TSource](IEnumerable`1 source, Func`2 predicate)
   at Microsoft.Azure.Quantum.QuantumMachineFactory.CreateMachine(IWorkspace workspace, String targetName, String storageAccountConnectionString) in C:\Users\samarsha\Source\Repos\microsoft\qsharp-runtime\src\Azure\Azure.Quantum.Client\Machine\QuantumMachineFactory.cs:line 30
   at Microsoft.Quantum.CsharpGeneration.EntryPointDriver.Azure.CreateMachine(AzureSettings settings) in C:\Users\samarsha\Source\Repos\microsoft\qsharp-runtime\src\Simulation\EntryPointDriver\Azure.cs:line 60
   at Microsoft.Quantum.CsharpGeneration.EntryPointDriver.Azure.Submit[TIn,TOut](IEntryPoint`2 entryPoint, ParseResult parseResult, AzureSettings settings) in C:\Users\samarsha\Source\Repos\microsoft\qsharp-runtime\src\Simulation\EntryPointDriver\Azure.cs:line 28
   at Microsoft.Quantum.CsharpGeneration.EntryPointDriver.Driver`3.Submit(ParseResult parseResult, AzureSettings settings) in C:\Users\samarsha\Source\Repos\microsoft\qsharp-runtime\src\Simulation\EntryPointDriver\Driver.cs:line 124
   at System.CommandLine.Invocation.CommandHandler.GetResultCodeAsync(Object value, InvocationContext context)
   at System.CommandLine.Invocation.ModelBindingCommandHandler.InvokeAsync(InvocationContext context)
   at System.CommandLine.Invocation.InvocationPipeline.<>c__DisplayClass4_0.<<BuildInvocationChain>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseParseErrorReporting>b__20_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass15_0.<<UseHelp>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass24_0.<<UseVersionOption>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass22_0.<<UseTypoCorrections>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseSuggestDirective>b__21_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseParseDirective>b__19_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<UseDebugDirective>b__11_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c.<<RegisterWithDotnetSuggest>b__10_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.CommandLine.Builder.CommandLineBuilderExtensions.<>c__DisplayClass13_0.<<UseExceptionHandler>b__0>d.MoveNext()

My understanding of AppDomain.CurrentDomain.GetAssemblies() is that it only returns assemblies that have been loaded into the currently running program (e.g. a type in the assembly has been used at least once before GetAssemblies() is called). Since the IonQ assembly hasn't been used before the standalone executable needs to instantiate it, it looks like CreateMachine isn't able to find it for me.

[rmshaffer]

Thanks for trying this out! Did you do anything special such that the existing Type.GetType() call was succeeding? When I tried to call the code using Type.GetType(), it couldn't find the assembly (even if it had already been loaded) unless I also included the version and the PublicKeyToken in the type string, i.e., in a format like this:
System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
I suppose we could always expose both versions of this, if we need to obtain the Type in different ways. IQ# does its own package loading and management at runtime, so I guess it's not surprising that this behaves differently.

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In reply to: 414007852 [](ancestors = 414007852)

[bamarsha]

No, I don't think I needed to do anything to get Type.GetType to work. Could you post the error message you get from it?

[bamarsha]

Could it have something to do with IQ# using signed versions of the IonQ assembly? That could mean that Type.GetType would fail for the standalone executable as well if it uses a signed version. (I'm not sure if the versions we have been using for testing have been signed or not.) We could try specifying just the assembly name and public key token (but not the version), but I am not sure if the public key token stays the same or changes when the version number is changed.

[rmshaffer]

Below is the error I get. I'll try just specifying the PublicKeyToken and not the version; I think that should be consistent for all signed versions, but I'd need to confirm this.

System.IO.FileNotFoundException
  HResult=0x80070002
  Message=Could not load file or assembly 'Microsoft.Quantum.Providers.IonQ, Culture=neutral, PublicKeyToken=null'. The system cannot find the file specified.
  Source=<Cannot evaluate the exception source>
  StackTrace:
  System.Private.CoreLib.dll!System.RuntimeTypeHandle.GetTypeByName(string name, bool throwOnError, bool ignoreCase, System.Runtime.CompilerServices.StackCrawlMarkHandle stackMark, System.Runtime.CompilerServices.ObjectHandleOnStack assemblyLoadContext, bool loadTypeFromPartialName, System.Runtime.CompilerServices.ObjectHandleOnStack type, System.Runtime.CompilerServices.ObjectHandleOnStack keepalive) Unknown
  System.Private.CoreLib.dll!System.RuntimeTypeHandle.GetTypeByName(string name, bool throwOnError, bool ignoreCase, ref System.Threading.StackCrawlMark stackMark, System.Runtime.Loader.AssemblyLoadContext assemblyLoadContext, bool loadTypeFromPartialName) Unknown
  System.Private.CoreLib.dll!System.RuntimeType.GetType(string typeName, bool throwOnError, bool ignoreCase, ref System.Threading.StackCrawlMark stackMark) Unknown
  System.Private.CoreLib.dll!System.Type.GetType(string typeName, bool throwOnError) Unknown
  Microsoft.Azure.Quantum.Client.dll!Microsoft.Azure.Quantum.QuantumMachineFactory.CreateMachine(Microsoft.Azure.Quantum.Workspace workspace, string targetName, string storageAccountConnectionString) Unknown
  Microsoft.Quantum.IQSharp.AzureClient.dll!Microsoft.Quantum.IQSharp.AzureClient.AzureClient.SubmitJobAsync(Microsoft.Jupyter.Core.IChannel channel, Microsoft.Quantum.IQSharp.IOperationResolver operationResolver, string operationName) Line 162 C#
> Microsoft.Quantum.IQSharp.AzureClient.dll!Microsoft.Quantum.IQSharp.AzureClient.SubmitMagic.RunAsync(string input, Microsoft.Jupyter.Core.IChannel channel) Line 63 C#
  Microsoft.Quantum.IQSharp.AzureClient.dll!Microsoft.Quantum.IQSharp.AzureClient.AzureClientMagicBase.Run(string input, Microsoft.Jupyter.Core.IChannel channel) Line 35 C#

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In reply to: 630504039 [](ancestors = 630504039)