How to get source namespace?

[vatosarmat]

Source namespace is needed to query diagnostic info with vim.diagnostic.get. How about provide it with get_sources()?

[jose-elias-alvarez]

At the moment you can query it using require("null-ls.diagnostics").get_namespace(id), which is exported here. That's an internal API, though, so it's not guaranteed to be stable, and I agree that this should be part of the default source data. PR welcome!