Add HostServices support in Out-of-Process Task Host - #12753
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This reverts commit 2992c64.
Removed unused error handling code and associated methods.
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Pull request overview
This PR enables out-of-process task hosts to access host objects registered via HostServices.RegisterHostObject(). Previously, tasks running in out-of-proc task hosts couldn't access these host objects because the necessary information wasn't transmitted to the task host process.
Key changes:
- Introduced packet version negotiation during handshake, incrementing PacketVersion from 1 to 2
- Added
HostServicesandtargetNamefields toTaskHostConfigurationwith conditional serialization - Propagated
HostServicesandtargetNamethrough the task execution call chain - Enhanced
HostServices.GetAnyMatchingMonikerNameOrITaskHost()to handle fully-qualified task names
Reviewed changes
Copilot reviewed 19 out of 19 changed files in this pull request and generated 4 comments.
Show a summary per file
| File | Description |
|---|---|
| src/Shared/TaskHostConfiguration.cs | Added HostServices and targetName fields with conditional serialization based on negotiated packet version |
| src/Shared/NodeEndpointOutOfProcBase.cs | Implemented PacketVersion exchange during handshake and updated to use NegotiatedPacketVersion |
| src/Shared/INodePacket.cs | Incremented PacketVersion to 2 and added GetNegotiatedPacketVersion helper method |
| src/Shared/CommunicationsUtilities.cs | Enhanced handshake protocol to read and negotiate packet versions between nodes |
| src/MSBuild/OutOfProcTaskHostNode.cs | Passed targetName and HostServices to task execution wrapper |
| src/MSBuild/OutOfProcTaskAppDomainWrapperBase.cs | Added logic to resolve and set host objects from HostServices |
| src/Build/Instance/TaskFactories/TaskHostTask.cs | Propagated HostServices through task initialization |
| src/Build/Instance/TaskFactories/AssemblyTaskFactory.cs | Added HostServices parameter to CreateTaskInstance |
| src/Build/Instance/HostServices.cs | Enhanced to handle fully-qualified task names by falling back to short name lookup |
| src/Build/BackEnd/TaskExecutionHost/TaskExecutionHost.cs | Added HostServices support in task initialization |
| src/Build/BackEnd/Components/RequestBuilder/TaskBuilder.cs | Passed HostServices from build request to task execution host |
| src/Build/BackEnd/Components/Communications/NodeProviderOutOfProcBase.cs | Updated to track and propagate negotiated packet version through NodeContext |
| src/Build.UnitTests/BackEnd/TaskHostConfiguration_Tests.cs | Updated all test cases to include new parameters (null HostServices and targetName) |
| src/Build.UnitTests/BackEnd/TaskExecutionHost_Tests.cs | Updated test initialization calls with null HostServices parameter |
| src/Build.UnitTests/BackEnd/AssemblyTaskFactory_Tests.cs | Updated all CreateTaskInstance calls with null HostServices parameter |
| src/MSBuild/MSBuild.csproj | Added blank line at end of file |
| src/Build/Instance/RunningObjectTable.cs | Removed BOM character from file |
| src/Framework/ITranslator.cs | Renamed PacketVersion to NegotiatedPacketVersion with updated documentation |
| src/Framework/BinaryTranslator.cs | Renamed PacketVersion to NegotiatedPacketVersion property |
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
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Fixes: #11510
Summary
This PR enables out-of-process task hosts to properly resolve host objects by passing HostServices and the target name through the task host communication protocol. Previously, tasks running in out-of-proc task hosts could not access host objects registered via HostServices.RegisterHostObject() because this information was not transmitted to the task host process.
Changes
Protocol Versioning & Negotiation
Introduced packet version negotiation during the handshake between parent and child nodes,
Child nodes now send their supported PacketVersion during handshake, allowing backward/forward-compatible communication between different MSBuild versions
Incremented PacketVersion from 1 to 2 to support the new fields - HostServices, targetName and project file path
Both new fields are conditionally serialized only when NegotiatedPacketVersion >= 2.
Updated OutOfProcTaskAppDomainWrapperBase.ExecuteTask() to accept and use HostServices and targetName
Task host now calls _hostServices.GetHostObject(taskFile, targetName, taskName) to resolve the host object before task execution
Fixed HostServices.GetAnyMatchingMonikerNameOrITaskHost() to handle fully-qualified task names by falling back to short name lookup
Handshake Flow (Before vs After)
Before
After