LSP Demystified - How towrite an LSP server in Python

on YouTube ↗26m

" summary

Shows an actual Python LSP server that parses SQL with SQLFluff, speaks over JSON-RPC in stdio mode, and publishes diagnostics via textDocument/publishDiagnostics. Completion answers use the AST for context (table vs column) and include documentation and hover info; the server also runs and explains queries and executes them against a database. Deployment uses pip (pip install sql-lsp) and the implementation uses pygls; the client needs only a ~10‑line patch, not heavyweight editor plugins.

AI-written summary · about

" chapters (15)

1. 0:00LSP introduction
2. 1:05Writing LSP server in Python
3. 3:59Language Server Protocol
4. 6:31Parsing code into an abstract syntax tree
5. 7:53Linting errors with SQL fluff
6. 10:01Smart autocomplete
7. 12:11Adding docs to autocomplete
8. 13:36LSP capabilities
9. 15:24Live demo: SQL LSP
10. 18:12Summary of implementation
11. 18:56Q&A: distribution & testing
12. 21:05Performance & debouncing
13. 22:30GitHub repo & structure
14. 23:56Extending LSP features
15. 24:59Code actions for refactor

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