ng.el

(setq my/message
      '(:jsonrpc "2.0" :method "initialize" :params
                 (:processId nil :rootPath "/home/yyoncho/Sources/CPP/testCPP" :clientInfo
                             (:name "emacs" :version "GNU Emacs 28.0.50 (build 5, x86_64-pc-linux-gnu, GTK+ Version 3.24.20, cairo version 1.16.0)\n of 2020-12-24")
                             :rootUri "file:///home/yyoncho/Sources/CPP/testCPP" :capabilities
                             ((workspace
                               (workspaceEdit
                                (documentChanges . t)
                                (resourceOperations .
                                                    ["create" "rename" "delete"]))
                               (applyEdit . t)
                               (symbol
                                (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 26])))
                               (executeCommand
                                (dynamicRegistration . :json-false))
                               (didChangeWatchedFiles
                                (dynamicRegistration . t))
                               (workspaceFolders . t)
                               (configuration . t))
                              (textDocument
                               (declaration
                                (linkSupport . t))
                               (definition
                                 (linkSupport . t))
                               (implementation
                                (linkSupport . t))
                               (typeDefinition
                                (linkSupport . t))
                               (synchronization
                                (willSave . t)
                                (didSave . t)
                                (willSaveWaitUntil . t))
                               (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 26]))
                                (hierarchicalDocumentSymbolSupport . t))
                               (formatting
                                (dynamicRegistration . t))
                               (rangeFormatting
                                (dynamicRegistration . t))
                               (rename
                                (dynamicRegistration . t)
                                (prepareSupport . t))
                               (codeAction
                                (dynamicRegistration . t)
                                (isPreferredSupport . t)
                                (codeActionLiteralSupport
                                 (codeActionKind
                                  (valueSet .
                                            ["" "quickfix" "refactor" "refactor.extract" "refactor.inline" "refactor.rewrite" "source" "source.organizeImports"]))))
                               (completion
                                (completionItem
                                 (snippetSupport . t)
                                 (documentationFormat .
                                                      ["markdown"])
                                 (resolveAdditionalTextEditsSupport . t))
                                (contextSupport . t))
                               (signatureHelp
                                (signatureInformation
                                 (parameterInformation
                                  (labelOffsetSupport . t))))
                               (documentLink
                                (dynamicRegistration . t)
                                (tooltipSupport . t))
                               (hover
                                (contentFormat .
                                               ["markdown" "plaintext"]))
                               (foldingRange
                                (dynamicRegistration . t))
                               (callHierarchy
                                (dynamicRegistration . :json-false))
                               (publishDiagnostics
                                (relatedInformation . t)
                                (tagSupport
                                 (valueSet .
                                           [1 2]))
                                (versionSupport . t)))
                              (window
                               (workDoneProgress . t)))
                             :initializationOptions nil :workDoneToken "1")
                 :id 1))
(lsp-async-send-request pipe (plist-get my/message :method)
                        (plist-get my/message :params))