Finalize command line interface

[javagl]

The Usage section in the README and the yargs arguments definitions describe the current state of the command line interface (CLI).

This interface has been set up "pragmatically", based on what I thought that it could make sense. It is by no means complete, and should be reviewed from a user- and usability perspective.

What has to be kept in mind is that it will have to be extended. For example, when the "Styling" validation is supposed to be added, the input file could be given as --styleFile (akin to the current --tilesetFile and other input files).

The CLI might also have to be extended significantly, namely when it should include certain configuration parameters for the validator. The configuration parameters still have to be decided upon. The issue #224 lists some possible configuration options.

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In general, I think that one thing should be supported in any case - namely, reading the configuration from a file. It should be possible to have all the options for the input and validation process summarized in a config.json that might look roughly like this:

{
    "tilesetsDirectory": "/data/tilesets/",
    "tilesetGlobPattern": "**/tileset.json",
    "validateContentTypes": [ "B3DM", "GLB" ],
    "validateAbsoluteUris": true,
    "ignoredIssueTypes": ["ASSET_VERSION_UNKNOWN", "TEMPLATE_URI_MISSING_VARIABLE_NAME" ]
}

This would allow "freezing" certain configurations, and to mainain them (in a repository, like source code), without having to resort to shell scripts or batch files....

[javagl]

There has been some progress for defining the CLI and how to manage the options. The basic approach is described in #224 (comment) . The 1-minute summary is:

There is an option to pass in a config.json at the CLI. This JSON file can contain all command line parameters that could otherwise be passed in directly via the command line. So the command line

npx ts-node src/main.ts --tilesetsDirectory specs/data/tilesets/ --tilesetGlobPattern **/*.json --writeReports

should be equivalent to

npx ts-node src/main.ts --configFile config.json

with config.json being

{
  "tilesetsDirectory": "specs/data/tilesets",
  "tilesetGlobPattern": "**/*.json",
  "writeReports": true
}

This only defines a way how to manage the command line options (reproducably and in a single file).
It does not yet define which options there actually are. So the command line arguments are not "finalized" yet (i.e. there is not yet a "1.0.0" version with stability guarantees). But it is becoming unlikely that there will be significant changes in the existing CLI options.