Configuration file with custom settings?

Question

I'm having difficulty attempting to explain what I mean but here I go..

I am looking for a configuration parser that does the following..

Allows me to configure REQUIRED settings and if they are not set then the program should not start.

Allow users to define as many 'custom settings' as they need. So for example, say you want to add some sort of redirect to the configuration, I'd like it to look like this.

redirect-1: 100->200

And that would hopefully 'redirect' 100 to 200. I would obviously build this logic into my program, but is there a library that will read sequential settings like redirect-1, redirect-2, etc. until it reaches the EOF? Hopefully I'm making sense.

Answer 1

I think what you are looking for is a configuration file parser that also provides a "schema validation" engine. Within the syntax of the schema validation language, you would specify which configuration variables are required (and their types), so the validation engine could verify that those variables are present and have values that comply with their types (for example, "42" is a valid integer, but "hello, world" is not).

XML has several competing schema validation languages , including XML Schema and RELAX NG . If you look on Amazon, you can find books on those.

JSON also has its own schema validation language .

The only other configuration language with its own schema validation language I can think of Config4* , which is one that I developed. If you want to read more about Config4*, then I suggest you read Chapters 2 and 3 of the Config4* Getting Started Guide ( PDF and HTML ) to get an overview of its syntax and API. Then skip to Chapter 9 to find full details of its schema validation language. The ignore rules (discussed in Section 9.2.6) can be used to specify that the schema validation engine should ignore some configuration variables/scopes.