clangd running in a docker: issues with --path-mappings (most likely)

[ubaldot]

Dear all,

I am running clangd on a docker and my lsp client is able to connect to it! I am so glad of that! :D
However, the setup is not yet fully functioning, although I am able to jump to some definition. I followed the tips herein provided and I have the source code folder both on the host mounted on the docker container.

The project root is mapped as it follows:
on the host: /home/yt75534/avap_example
on the docker: /app
That is, I have the src on both the host and the docker. I have the build in the docker along with a compile_commands.json.
Then, on the docker I also have a /host_home folder which is my home folder on the host.

I run the clangd server through a .sh file that ends up with the following command:

docker run .... clangd --path-mappings=/home/yt75534/avap_example=/app,/home/yt75534=/host_home,/home/yt75534/docker_include/c++/9:/usr/include/c++/9 --log=verbose

So far, so (almost) good.

In-fact, by observing the error messages reported by my LSP client (which is this ) I have the following error(s):

I[18:14:46.283] <-- textDocument/didOpen
I[18:14:46.284] ASTWorker building file /home/yt75534/avap_example/hello_world_application/app/src/hello_world_application.h version 1 with command inferred from /app/hello_world_application/app/src/hello_world_application.cpp
[/app/build/gcc9_linux_x86_64-machine]
/usr/bin/g++-9 --driver-mode=g++ "-DCMAKE_INTDIR=\"Debug\"" -isystem /host_home/.avapcache/AmsrDevelopment/r8.23.40-16-1.0.0-90-gb9d914ddd-gcc9_linux_x86_64-Release/include -Wall -Wextra -Wnon-virtual-dtor -Wconversion -Wold-style-cast -pedantic -Wshadow -g -fpch-preprocess -fdiagnostics-color=always -Wsign-conversion -c -x c++-header -std=c++17 -resource-dir=/home/yt75534/miniforge3/envs/platformio/lib/clang/16 -- /home/yt75534/avap_example/hello_world_application/app/src/hello_world_application.h
E[18:14:46.284] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
E[18:14:46.353] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
I[18:14:46.357] Built preamble of size 216272 for file /home/yt75534/avap_example/hello_world_application/app/src/hello_world_application.h version 1 in 0.00 seconds
E[18:14:46.357] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
I[18:14:46.378] <-- textDocument/didChange

which to me it is obvious because /app/build/gcc9_linux_x86_64-machine does not exists in the host. I think the folder to set CWD should be /home/yt75534/avap_example/build/gcc9_linux_x86_64-machine and not /app/build/gcc9_linux_x86_64-machine as reported by the error message due to the --path-mappings passed to the clangd invocation, right?

What I am doing wrong?

[HighCommander4]

I'm not too familiar with docker setups and --path-mappings but one thing to note is that messages formatted like this:

E[18:14:46.284] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory

are coming from the server (the client is just making the server's logs available for viewing).

So, the message seems to indicate that the path /app/build/gcc9_linux_x86_64-machine does not exist wherever the server is running (in this case I guess that would be inside the container).

[ubaldot]

I understand the error message, but the point is that such a path exists in the docker but it doesn’t exist in my host. That is why I used the mapping. :)

[ubaldot]

I am not sure I can capture all of them, but here is a list of what I managed to log:

Messages:

03/02/24 10:24:45: Received {'method': 'textDocument/publishDiagnostics', 'jsonrpc': '2.0', 'params': {'diagnostics': [], 'uri': 'file:///home/yt75534/avap_example/hello_world_application/app/src/main.cpp'}}
03/02/24 10:24:45: Received {'method': 'textDocument/publishDiagnostics', 'jsonrpc': '2.0', 'params': {'diagnostics': [{'source': 'clang', 'range': {'end': {'character': 18, 'line': 0}, 'start': {'character': 9, 'line': 0}}, 'code': 'pp_file_not_found', 'message': '''csignal'' file not found', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 3, 'line': 15}, 'start': {'character': 0, 'line': 15}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 15, 'line': 15}, 'start': {'character': 12, 'line': 15}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 12, 'line': 22}, 'start': {'character': 4, 'line': 22}}, 'code': 'unknown_typename', 'message': 'Unknown type name ''sigset_t''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 11, 'line': 23}, 'start': {'character': 4, 'line': 23}}, 'code': 'unknown_typename', 'message': 'Unknown type name ''int32_t''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 58, 'line': 28}, 'start': {'character': 51, 'line': 28}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''SIGTERM''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 57, 'line': 30}, 'start': {'character': 51, 'line': 30}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''SIGINT''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 11, 'line': 34}, 'start': {'character': 8, 'line': 34}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 67, 'line': 34}, 'start': {'character': 64, 'line': 34}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 28, 'line': 37}, 'start': {'character': 21, 'line': 37}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''SIGTERM''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 48, 'line': 37}, 'start': {'character': 42, 'line': 37}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''SIGINT''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 7, 'line': 42}, 'start': {'character': 4, 'line': 42}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 59, 'line': 42}, 'start': {'character': 56, 'line': 42}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 12, 'line': 50}, 'start': {'character': 4, 'line': 50}}, 'code': 'unknown_typename', 'message': 'Unknown type name ''sigset_t''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 11, 'line': 56}, 'start': {'character': 8, 'line': 56}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''ara''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 31, 'line': 59}, 'start': {'character': 20, 'line': 59}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''SIG_SETMASK''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 47, 'line': 59}, 'start': {'character': 43, 'line': 59}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''NULL''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 7, 'line': 68}, 'start': {'character': 4, 'line': 68}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 61, 'line': 68}, 'start': {'character': 58, 'line': 68}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''std''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 7, 'line': 74}, 'start': {'character': 4, 'line': 74}}, 'code': 'undeclared_var_use', 'message': 'Use of undeclared identifier ''ara''', 'severity': 1}, {'source': 'clang', 'range': {'end': {'character': 0, 'line': 0}, 'start': {'character': 0, 'line': 0}}, 'code': 'fatal_too_many_errors', 'message': 'Too many errors emitted, stopping now', 'severity': 1}], 'uri': 'file:///home/yt75534/avap_example/hello_world_application/app/src/main.cpp', 'version': 4}}

Errors

I[10:30:46.642] <-- textDocument/didClose
I[10:30:46.642] --> textDocument/publishDiagnostics
I[10:30:46.642] <-- textDocument/didOpen
I[10:30:46.643] ASTWorker building file /home/yt75534/avap_example/hello_world_application/app/src/main.cpp version 4 with command inferred from /app/client1/app/src/main.cpp
[/app/build/gcc9_linux_x86_64-machine]
/usr/bin/g++-9 --driver-mode=g++ -DAMSR_LOGUTI_IS_AMSR_LOGGING "-DCMAKE_INTDIR=\"Debug\"" -I/app/build/gcc9_linux_x86_64-machine/client1/app/DvACfg_Gen/Executable_Client1/include -isystem /host_home/.avapcache/AmsrDevelopment/r8.23.40-16-1.0.0-90-gb9d914ddd-gcc9_linux_x86_64-Release/include -isystem /host_home/.avapcache/AmsrDevelopment/r8.23.40-16-1.0.0-90-gb9d914ddd-gcc9_linux_x86_64-Release/include_r18_03 -Wall -Wextra -Wnon-virtual-dtor -Wconversion -Wold-style-cast -pedantic -Wshadow -g -fpch-preprocess -fdiagnostics-color=always -Wsign-conversion -c -std=c++17 -resource-dir=/home/yt75534/miniforge3/envs/platformio/lib/clang/16 -- /home/yt75534/avap_example/hello_world_application/app/src/main.cpp
E[10:30:46.643] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
E[10:30:46.694] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
I[10:30:46.699] Built preamble of size 218496 for file /home/yt75534/avap_example/hello_world_application/app/src/main.cpp version 4 in 0.00 seconds
E[10:30:46.699] VFS: failed to set CWD to /app/build/gcc9_linux_x86_64-machine: No such file or directory
I[10:30:46.756] --> textDocument/publishDiagnostics

Capabilities:

'clangd' Language Server Capabilities
=====================================
astProvider: true
callHierarchyProvider: true
clangdInlayHintsProvider: true
codeActionProvider: {'codeActionKinds': ['quickfix', 'refactor', 'info']}
compilationDatabase: {'automaticReload': true}
completionProvider: {'resolveProvider': false, 'triggerCharacters': ['.', '<', '>', ':', '"', '/', '*']}
declarationProvider: true
definitionProvider: true
documentFormattingProvider: true
documentHighlightProvider: true
documentLinkProvider: {'resolveProvider': false}
documentOnTypeFormattingProvider: {'moreTriggerCharacter': [], 'firstTriggerCharacter': ' '}
documentRangeFormattingProvider: true
documentSymbolProvider: true
executeCommandProvider: {'commands': ['clangd.applyFix', 'clangd.applyTweak']}
foldingRangeProvider: true
hoverProvider: true
implementationProvider: true
inlayHintProvider: true
memoryUsageProvider: true
referencesProvider: true
renameProvider: true
selectionRangeProvider: true
semanticTokensProvider: {'full': {'delta': true}, 'legend': {'tokenTypes': ['variable', 'variable', 'parameter', 'function', 'method', 'function', 'property', 'variable', 'class', 'interface', 'enum', 'enumMember', 'type', 'type', 'unknown', 'namespace', 'typeParameter', 'concept', 'type', 'macro', 'modifier', 'operator', 'comment'], 'tokenModifiers': ['declaration', 'definition', 'deprecated', 'deduced', 'readonly', 'static', 'abstract', 'virtual', 'dependentName', 'defaultLibrary', 'usedAsMutableReference', 'usedAsMutablePointer', 'constructorOrDestructor', 'userDefined', 'functionScope', 'classScope', 'fileScope', 'globalScope']}, 'range': false}
signatureHelpProvider: {'triggerCharacters': ['(', ')', '{', '}', '<', '>', ',']}
standardTypeHierarchyProvider: true
textDocumentSync: {'save': true, 'change': 2, 'openClose': true}
typeDefinitionProvider: true
typeHierarchyProvider: true
workspaceSymbolProvider: true
~additionalInitResult_offsetEncoding: 'utf-32'
~additionalInitResult_serverInfo: {'version': 'clangd version 16.0.6 (https://github.com/conda-forge/clangdev-feedstock ecb39558caaa7f6d2adb31bb404f5141905457a4) linux x86_64-conda-linux-gnu', 'name': 'clangd'}

Init requests:

'clangd' Language Server Initialize Request
===========================================
capabilities: {'workspace': {'workspaceFolders': true, 'configuration': true, 'workspaceEdit': {'resourceOperations': ['rename', 'create', 'delete']}, 'symbol': {'dynamicRegistration': false}, 'applyEdit': true}, 'offsetEncoding': ['utf-32', 'utf-16'], 'window': {}, 'general': {'positionEncodings': ['utf-32', 'utf-16']}, 'textDocument': {'callHierarchy': {'dynamicRegistration': false}, 'rename': {'prepareSupport': false, 'dynamicRegistration': false}, 'codeAction': {'isPreferredSupport': true, 'disabledSupport': true, 'codeActionLiteralSupport': {'codeActionKind': {'valueSet': ['', 'quickfix', 'refactor', 'refactor.extract', 'refactor.inline', 'refactor.rewrite', 'source', 'source.organizeImports']}}, 'dynamicRegistration': false}, 'completion': {'completionItem': {'insertReplaceSupport': false, 'snippetSupport': false, 'resolveSupport': {'properties': ['detail', 'documentation']}, 'documentationFormat': ['markdown', 'plaintext']}, 'dynamicRegistration': false, 'completionItemKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}}, 'formatting': {'dynamicRegistration': false}, 'codeLens': {'dynamicRegistration': false}, 'inlayHint': {'dynamicRegistration': false}, 'hover': {'dynamicRegistration': false, 'contentFormat': ['markdown', 'plaintext']}, 'rangeFormatting': {'dynamicRegistration': false}, 'declaration': {'dynamicRegistration': false, 'linkSupport': true}, 'references': {'dynamicRegistration': false}, 'selectionRange': {'dynamicRegistration': false}, 'typeHierarchy': {'dynamicRegistration': false}, 'foldingRange': {'rangeLimit': 5000, 'foldingRange': {'collapsedText': true}, 'dynamicRegistration': false, 'foldingRangeKind': {'valueSet': ['comment', 'imports', 'region']}, 'lineFoldingOnly': true}, 'documentSymbol': {'symbolKind': {'valueSet': [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}, 'dynamicRegistration': false, 'labelSupport': false, 'hierarchicalDocumentSymbolSupport': true}, 'publishDiagnostics': {'dataSupport': true, 'relatedInformation': false, 'codeDescriptionSupport': true, 'versionSupport': true}, 'synchronization': {'didSave': true, 'WillSaveWaitUntil': false, 'willSave': false, 'dynamicRegistration': false}, 'documentHighlight': {'dynamicRegistration': false}, 'implementation': {'dynamicRegistration': false, 'linkSupport': true}, 'typeDefinition': {'dynamicRegistration': false, 'linkSupport': true}, 'semanticTokens': {'serverCancelSupport': false, 'requests': {'full': {'delta': true}, 'range': false}, 'multilineTokenSupport': false, 'dynamicRegistration': false, 'overlappingTokenSupport': false, 'tokenTypes': ['type', 'class', 'enum', 'interface', 'struct', 'typeParameter', 'parameter', 'variable', 'property', 'enumMember', 'event', 'function', 'method', 'macro', 'keyword', 'modifier', 'comment', 'string', 'number', 'regexp', 'operator'], 'tokenModifiers': ['declaration', 'definition', 'readonly', 'static', 'deprecated', 'abstract', 'async', 'modification', 'documentation', 'defaultLibrary'], 'formats': ['relative'], 'augmentsSyntaxTokens': true}, 'signatureHelp': {'signatureInformation': {'activeParameterSupport': true, 'documentationFormat': ['markdown', 'plaintext']}, 'dynamicRegistration': false}, 'definition': {'dynamicRegistration': false, 'linkSupport': true}}}
clientInfo: {'version': '9000749', 'name': 'Vim'}
initializationOptions: {}
processId: 1459
rootPath: '/home/yt75534/avap_example'
rootUri: 'file:///home/yt75534/avap_example/'
trace: 'off'
workspaceFolders: [{'uri': 'file:///home/yt75534/avap_example/', 'name': 'avap_example'}]

and this is a screenshot from the docker:

[HighCommander4]

I was thinking of the server's logs, the one you have listed under "Errors", but starting from the server startup.

For an example of a complete server log, see this report and search for "Logs".

[ubaldot]

I see, but I am not sure I can capture them. What I am doing in my client is the following:

LspServer debug on
LspServer restart
LspServer show messages (which says no messages received from server)
LspServer debug errors (which returns the errors that I posted) 

I will investigate how to capture them, but in the meantime any other ideas are welcome!

[HighCommander4]

That might be a question for your client's issue tracker. From the client's point of view, the log we're looking for is what the server process prints to its stderr.

[ubaldot]

I think I found the issue. The client was connecting to a local clangd server instead of the clangd server located in the docker.
Once fixed the issue, I noticed that the client actually fails to connect to the remote server. I have to figure out how to make the client to connect to the server running in the container and we should be set.

I'll update this discussion once I will have found it out.

[ubaldot]

I finally managed to make it work. You can use a .sh script in your LSP client configuration that end up a docker run ... clangd ... but user has to carefully review the option passed to the docker run (for example you cannot use -t). There is still something to fix with some missing libraries but I would say that pretty much we are there. We have connection and LSP feature.
Thanks for the support!