Document Uri length crashing the language server

[jaredpar]

Type: Bug

Issue Description

When editting the dotnet/sdk repository in C# DevKit the language server is crashing with the following error:

2025-04-29 17:59:47.008 [info] [Error - 5:59:47 PM] [LanguageServerHost] System.UriFormatException: Invalid URI: The Uri string is too long.
   at System.Uri.CreateThis(String uri, Boolean dontEscape, UriKind uriKind, UriCreationOptions& creationOptions)
   at System.Uri..ctor(String uriString)
   at Roslyn.LanguageServer.Protocol.DocumentUriConverter.Read(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options) in /_/src/LanguageServer/Protocol/Protocol/Converters/DocumentUriConverter.cs:line 17
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
   at System.Text.Json.Serialization.Metadata.JsonPropertyInfo`1.ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader)
   at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
   at System.Text.Json.Serialization.Metadata.JsonPropertyInfo`1.ReadJsonAndSetMember(Object obj, ReadStack& state, Utf8JsonReader& reader)
   at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
   at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
   at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, T& value, JsonSerializerOptions options, ReadStack& state)
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo`1.Deserialize(Utf8JsonReader& reader, ReadStack& state)
   at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 utf8Json, JsonTypeInfo`1 jsonTypeInfo, Nullable`1 actualByteCount)
   at System.Text.Json.JsonSerializer.Deserialize[TValue](JsonElement element, JsonSerializerOptions options)
   at Microsoft.CommonLanguageServerProtocol.Framework.SystemTextJsonLanguageServer`1.DeserializeRequest[TRequest](Object serializedRequest, RequestHandlerMetadata metadata) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/SystemTextJsonLanguageServer.cs:line 49
   at Microsoft.CommonLanguageServerProtocol.Framework.QueueItem`1.TryDeserializeRequest[TRequest](AbstractLanguageServer`1 languageServer, RequestHandlerMetadata requestHandlerMetadata, Boolean isMutating, TRequest& request) in /_/src/LanguageServer/Microsoft.CommonLanguageServerProtocol.Framework/QueueItem.cs:line 120

Steps to Reproduce

1. Create a GitHub Codespace for https://github.com/dotnet/sdk
2. Open the Codespace in VS Code and edit both .csproj and .cs files
3. VS Code will eventually popup that the language server crashed too many times and it will no longer be restarted.

Expected Behavior

No crash

Actual Behavior

Logs

exthost.zip

Environment information

VSCode version: 1.100.0-insider
C# Extension: 2.72.34
Using OmniSharp: false

Dotnet Information

Host:
Version: 9.0.4
Architecture: x64
Commit: f57e6dc747
RID: linux-x64

.NET SDKs installed:
No SDKs were found.

.NET runtimes installed:
Microsoft.NETCore.App 9.0.4 [/home/vscode/.vscode-remote/data/User/globalStorage/ms-dotnettools.vscode-dotnet-runtime/.dotnet/9.0.4~x64/shared/Microsoft.NETCore.App]

Other architectures found:
None

Environment variables:
DOTNET_ROOT [/workspaces/sdk/.dotnet]

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

Download .NET:
https://aka.ms/dotnet/download

Visual Studio Code Extensions

Extension	Author	Version	Folder Name
azure-pipelines	ms-azure-devops	1.249.0	ms-azure-devops.azure-pipelines-1.249.0
claude-dev	saoudrizwan	3.13.3	saoudrizwan.claude-dev-3.13.3
copilot	GitHub	1.309.0	github.copilot-1.309.0
csdevkit	ms-dotnettools	1.18.25	ms-dotnettools.csdevkit-1.18.25-linux-x64
csharp	ms-dotnettools	2.72.34	ms-dotnettools.csharp-2.72.34-linux-x64
docker	docker	0.4.10	docker.docker-0.4.10-linux-x64
EditorConfig	EditorConfig	0.17.2	editorconfig.editorconfig-0.17.2
hexeditor	ms-vscode	1.11.1	ms-vscode.hexeditor-1.11.1
powershell	ms-vscode	2025.0.0	ms-vscode.powershell-2025.0.0
vscode-azureappservice	ms-azuretools	0.26.0	ms-azuretools.vscode-azureappservice-0.26.0
vscode-azureresourcegroups	ms-azuretools	0.10.9	ms-azuretools.vscode-azureresourcegroups-0.10.9
vscode-azurestaticwebapps	ms-azuretools	0.13.1	ms-azuretools.vscode-azurestaticwebapps-0.13.1
vscode-docker	ms-azuretools	1.29.5	ms-azuretools.vscode-docker-1.29.5
vscode-dotnet-runtime	ms-dotnettools	2.3.3	ms-dotnettools.vscode-dotnet-runtime-2.3.3
vscode-github-actions	github	0.27.1	github.vscode-github-actions-0.27.1
vscode-markdownlint	DavidAnson	0.59.0	davidanson.vscode-markdownlint-0.59.0
vscode-pull-request-github	GitHub	0.108.0	github.vscode-pull-request-github-0.108.0
vscode-versionlens	pflannery	1.20.1	pflannery.vscode-versionlens-1.20.1
vscodeintellicode-csharp	ms-dotnettools	2.2.3	ms-dotnettools.vscodeintellicode-csharp-2.2.3-linux-x64
vsliveshare	ms-vsliveshare	1.0.5948	ms-vsliveshare.vsliveshare-1.0.5948

Extension version: 2.74.24
VS Code version: Code - Insiders 1.100.0-insider (7dbf25d8427b59f519d04587e71a9d3dfb77224c, 2025-04-10T05:04:51.401Z)
OS version: Windows_NT x64 10.0.26100
Modes:
Remote OS version: Linux x64 6.8.0-1026-azure

System Info

Item	Value
CPUs	11th Gen Intel(R) Core(TM) i7-1185G7 @ 3.00GHz (8 x 2995)
GPU Status	2d_canvas: enabled canvas_oop_rasterization: enabled_on direct_rendering_display_compositor: disabled_off_ok gpu_compositing: enabled multiple_raster_threads: enabled_on opengl: enabled_on rasterization: enabled raw_draw: disabled_off_ok skia_graphite: disabled_off video_decode: enabled video_encode: enabled vulkan: disabled_off webgl: enabled webgl2: enabled webgpu: enabled webnn: disabled_off
Load (avg)	undefined
Memory (System)	15.85GB (2.08GB free)
Process Argv	--crash-reporter-id 49d07ddb-004f-4a1d-ae93-bbce6fadd469
Screen Reader	no
VM	0%

Item	Value
Remote	Codespaces: studious space spork
OS	Linux x64 6.8.0-1026-azure
CPUs	AMD EPYC 7763 64-Core Processor (16 x 0)
Memory (System)	62.79GB (58.34GB free)
VM	0%

A/B Experiments

vsliv368cf:30146710
vspor879:30202332
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vspor363:30204092
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pythonvspyt551:31249597
vscod805cf:30301675
c4g48928:30535728
2i9eh265:30646982
962ge761:30841072
dsvsc014:30777825
dsvsc015:30821418
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pythontbext0:30879054
cppperfnew:30980852
dwnewjupytercf:31046870
pythonrstrctxt:31093868
nativeloc1:31118317
e80f6927:31120813
dwcopilot:31158714
c3hdf307:31184662
471b6256:31240254
6074i472:31201624
dwoutputs:31242946
customenabled:31248079
hdaa2157:31222309
copilot_t_ci:31222730
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pythoneinst12:31251391
bgtreat:31252123
c7cif404:31294349
5b33h341:31251110
31787653:31262186
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pythonpulldiag:31287486
6gi0g917:31259950
61ibe868:31282443
996jf627:31264550
pythonrdcb7:31268811
usemplatestapi:31297334
i53e4855:31295464
747dc170:31275146
pythoncompactctx:31296835
g20af354:31278749
6518g693:31296556
pylancecolor:31288664
generatesymbolt:31280541
convertfstringf:31280702
gendocf:31280703
3g1ci329:31285109
pylancequickfixf:31296867

[dibarbet]

@jaredpar I'm working on a fix for this (dotnet/roslyn#76691) and other URI parsing issues - but I haven't ever been able to reproduce the too long issue. Would you be able to set the log level to Trace, then include the 'C# LSP Trace logs' window contents? that will log the actual URI that is too long.

[dibarbet]

Should be resolved (at least prevent the server from crashing) by dotnet/roslyn#76691 in an upcoming release.

If the problematic URI pointed to a real file on disk, we would still have issues (as we cannot parse the URI to map to a local file). However given that the URI is too long, it is extremely unlikely that it represents a real file. More likely its some virtual file with a bunch of query parameters. The only thing we can do is put it in misc, which is what we will do with the change linked above.

Closing this as it will be resolved in the next prerelease. Can revisit if we can get trace logs or further issues are encountered.