Suggestion: populate annotations using comment/JSDoc values

[thw0rted]

I see that you can set schema annotations like "description", and "examples" manually using the @JSONSchema decorator, but this information is lost when building a typing (.d.ts) file. For example, if you write

@JSONSchema({description: 'Full name of user'}
@IsString()
@MaxLength(40)
name: string;

the generated .d.ts file just has name: string. On the other hand, if you put the description in a comment (/** Full name of user */) above the property declaration, and set removeComments: false in tsconfig.json, the generated file includes the comment. This allows consumers of the emitted typings to get helpful tooltips in their IDE. Unfortunately, getting the tooltip in both places -- the .d.ts file, and the JSON Schema output -- requires duplicating the annotation in both the JSDoc comment and the JSONSchema decorator.

I don't know if the generator has the full TS AST available to it during schema generation, but if possible, it would be great to pull any matching annotations from JSDoc and set the corresponding values in the emitted schema. I think it would be possible to copy description (from @description tag or just the body of the comment), deprecated, default, and examples.