Better argument parsing

[Andrew-Morozko]

49 but on top of the current main branch, git defeated me:(

[Andrew-Morozko]

• [x] Switch to cobra

[traut]

the specs for CLI:

• 2 subcommands:

  • render
    • the subcommand renders the specified document into Markdown and outputs it either to stdout or to a file.
    • target -- a required positional argument. Specifies the name of the document to be rendered as document.<name>.
    • --out-file -- an optional argument. Specifies the name of the output file where the rendered document must be saved to.
    • if --out-file is not set, the Markdown is printed to stdout

  • data

    • the subcommand executes the data blog and prints out prettified (and highlighted) JSON to stdout

    • target -- a required positional argument. Specifies a path to a data block to be executed -- a data block must be inside a document, so the path should have syntax of document.<doc-name>.data.<plugin-name>.<data-name>.

• subcommand-independent arguments
  • --source-dir -- an optional argument that accepts a path to a directory with *.fabric files. Default value: . (current directory)
  • --log-output -- an optional argument that accepts plain or json. Configures a handler for the logging. Default value: plain (colored plain text output)
  • --logging-level -- an optional argument that specifies the logging level. Default value: info
  • -v -- a shortcut to --logging-level debug

[traut]

moved the spec to https://github.com/blackstork-io/fabric/issues/70

[Andrew-Morozko]

Reimplemented parsing in cobra with minimal tweaks to the text of the spec.

• [x] Waiting to connect arg parser to logging solution (once it's decided which one do we want)

[Andrew-Morozko]

Cobra argument parsing, default slog logger configuration, and remote plugin logging are done. Ready to be merged as soon as we write some description for fabric --help (see review comment)