chore(transport): retire the internal TCP runtime

[yordis]

• Removes an unsupported transport runtime so the server has one internal communication path.

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Run ID: 2dc18665-68d4-4b2f-8e87-a33932117ca9

📥 Commits

Reviewing files that changed from the base of the PR and between d04c94d and 91fdde0.

📒 Files selected for processing (49)

• src/EventStore.Core.Tests/EventStore.Core.Tests.csproj
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca/ca.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca/ca.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca_untrusted/ca.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca_untrusted/ca.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/generate_ca.sh
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/generate_cert.sh
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node1/node1.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node1/node1.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node2/node2.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node2/node2.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node3/node3.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node3/node3.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/untrusted/untrusted.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/untrusted/untrusted.key
• src/EventStore.Core/Authorization/AuthorizationPolicies/LegacyPolicySelectorFactory.cs
• src/EventStore.Core/ClusterVNode.cs
• src/EventStore.Core/EventStore.Core.csproj
• src/EventStore.Core/Helpers/IAsyncMessageFramer.cs
• src/EventStore.Core/Helpers/LengthPrefixSuffixFramer.cs
• src/EventStore.Core/Helpers/MessageFramingException.cs
• src/EventStore.Core/Messages/ClientMessage.cs
• src/EventStore.Core/Messages/TcpClientMessageDto.cs
• src/EventStore.Core/Messages/TcpMessage.cs
• src/EventStore.Core/Messaging/CoreMessage.cs
• src/EventStore.Core/NodeTcpOptions.cs
• src/EventStore.Core/Services/AuthorizationGateway.cs
• src/EventStore.Core/Services/Monitoring/SystemStatsHelper.cs
• src/EventStore.Core/Services/PersistentSubscription/PersistentSubscriptionService.cs
• src/EventStore.Core/Services/Replication/LogRecordFramer.cs
• src/EventStore.Core/Services/Replication/TransactionFramer.cs
• src/EventStore.Core/Services/RequestForwardingService.cs
• src/EventStore.Core/Services/Storage/ReaderIndex/EventFilter.cs
• src/EventStore.Core/Services/SubscriptionsService.cs
• src/EventStore.Core/Services/TcpSendService.cs
• src/EventStore.Core/Services/Transport/Tcp/ClientTcpDispatcher.cs
• src/EventStore.Core/Services/Transport/Tcp/ClientWriteTcpDispatcher.cs
• src/EventStore.Core/Services/Transport/Tcp/ITcpDispatcher.cs
• src/EventStore.Core/Services/Transport/Tcp/ProtobufExtensions.cs
• src/EventStore.Core/Services/Transport/Tcp/SendOverTcpEnvelope.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpCommand.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpConnectionManager.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpDispatcher.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpPackage.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpService.cs
• src/EventStore.Core/Services/Transport/Tcp/UnableToAcquireStreamException.cs
• src/EventStore.Core/Settings/VNodeSettings.cs
• src/EventStore.Core/Util/Opts.cs
• src/Protos/ClientAPI/ClientMessageDtos.proto

💤 Files with no reviewable changes (42)

• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca/ca.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/untrusted/untrusted.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca_untrusted/ca.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/untrusted/untrusted.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/generate_cert.sh
• src/EventStore.Core/Services/Monitoring/SystemStatsHelper.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpPackage.cs
• src/EventStore.Core/Services/Transport/Tcp/ClientWriteTcpDispatcher.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca/ca.crt
• src/EventStore.Core/Settings/VNodeSettings.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/ca_untrusted/ca.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node2/node2.crt
• src/EventStore.Core/Messages/ClientMessage.cs
• src/EventStore.Core/Services/TcpSendService.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node2/node2.key
• src/EventStore.Core/Services/Transport/Tcp/UnableToAcquireStreamException.cs
• src/EventStore.Core/Services/Transport/Tcp/ClientTcpDispatcher.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node3/node3.crt
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node3/node3.key
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/generate_ca.sh
• src/EventStore.Core/ClusterVNode.cs
• src/EventStore.Core/Services/Transport/Tcp/SendOverTcpEnvelope.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node1/node1.crt
• src/EventStore.Core/Services/RequestForwardingService.cs
• src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/node1/node1.key
• src/EventStore.Core/Messages/TcpMessage.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpConnectionManager.cs
• src/EventStore.Core/Services/Transport/Tcp/ProtobufExtensions.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpDispatcher.cs
• src/EventStore.Core/NodeTcpOptions.cs
• src/Protos/ClientAPI/ClientMessageDtos.proto
• src/EventStore.Core/Messaging/CoreMessage.cs
• src/EventStore.Core/Services/Transport/Tcp/TcpCommand.cs
• src/EventStore.Core/Services/Transport/Tcp/ITcpDispatcher.cs
• src/EventStore.Core/Services/SubscriptionsService.cs
• src/EventStore.Core/Authorization/AuthorizationPolicies/LegacyPolicySelectorFactory.cs
• src/EventStore.Core/EventStore.Core.csproj
• src/EventStore.Core/Services/Transport/Tcp/TcpService.cs
• src/EventStore.Core/Util/Opts.cs
• src/EventStore.Core/Messages/TcpClientMessageDto.cs
• src/EventStore.Core.Tests/EventStore.Core.Tests.csproj
• src/EventStore.Core/Services/PersistentSubscription/PersistentSubscriptionService.cs

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Walkthrough

The change removes the legacy TCP transport, its protocol definitions, dispatchers, connection services, settings, project wiring, and test certificates. It adds core framing abstractions and updates event-filter parsing and authentication handling to use remaining core and client-message paths.

Changes

TCP transport removal

Layer / File(s)	Summary
Core framing and filter updates src/EventStore.Core/Helpers/*, src/EventStore.Core/Services/Replication/*, src/EventStore.Core/Services/Storage/ReaderIndex/EventFilter.cs	Adds IAsyncMessageFramer and MessageFramingException, updates framing references, and constructs event filters directly during parsing.
TCP protocol and dispatch removal src/Protos/ClientAPI/ClientMessageDtos.proto, src/EventStore.Core/Messages/*, src/EventStore.Core/Services/Transport/Tcp/*	Removes TCP protobuf contracts, message types, package serialization, dispatchers, connection helpers, and TCP send infrastructure.
Runtime transport and settings removal src/EventStore.Core/ClusterVNode.cs, src/EventStore.Core/Services/*, src/EventStore.Core/Settings/*, src/EventStore.Core/*.csproj, src/EventStore.Core/NodeTcpOptions.cs, src/EventStore.Core/Util/Opts.cs	Removes TCP listeners, connection handling, TCP statistics, TCP-specific cleanup and policy wiring, TCP settings, and project references. Not-authenticated handling remains on ClientMessage.
TCP test fixture cleanup src/EventStore.Core.Tests/EventStore.Core.Tests.csproj, src/EventStore.Core.Tests/Services/Transport/Tcp/test_certificates/*	Removes TCP test-project references, embedded certificate resources, certificate files, and certificate-generation scripts.

Priority: ➖ Normal

Estimated code review effort: 5 (Critical) | ~90 minutes

Change: Other

Merge Risk: ⚪ Minimal · up to 91fdd

No actionable merge-blocking risk is established for the TCP runtime removal.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 9.09% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 11 functions across 7 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly identifies the main change: retiring the internal TCP runtime. It is concise and specific.
Description check	✅ Passed	The description directly states that the unsupported transport runtime was removed and that the server now uses one internal communication path.

✨ Finishing Touches 💡 2

📝 Generate docstrings 💡

• Create stacked PR
• Commit on current branch

🛠️ Fix failing CI checks 💡

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch yordis/chore-remove-legacy-tcp-runtime

---

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_{A rabbit checks the vanished wire,
The old TCP paths retire,
New framers hold the byte stream tight,
Filters parse with clearer sight,
And test keys fade from light.}

_{Comment @coderabbitai help to get the list of available commands.}

[cursor]

PR Summary

High Risk
Large removal of a client-facing transport path and related auth/forwarding/subscription disconnect handling; deployments or tools still using native TCP will break unless they use gRPC/HTTP.

Overview
Removes the legacy TCP client transport from the server core so client and internal messaging no longer depend on EventStore.Transport.Tcp, TCP-specific protobuf DTOs, or the ClientMessageDtos.proto wire format.

The bulk of the change deletes the TCP stack (TcpService, connection managers, dispatchers, TcpMessage, send/forwarding hooks) and drops TCP-only behavior from subscriptions, persistent subscriptions, authorization forwarding, and monitoring (including Statistics.Tcp and proc-tcp-* stats). Replication framing stays by inlining IAsyncMessageFramer / MessageFramingException under EventStore.Core.Helpers instead of the transport package.

Follow-up cleanups simplify APIs that existed mainly for TCP: NotHandled.LeaderInfo is HTTP-only, event filter parsing no longer goes through Client.Messages.Filter, and test project references plus embedded TCP test certificates are removed.

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