Apache Solr for TYPO3 CMS

This is a known issue, but needs some more advanced solution. The restrictions of indexing configurations need to be checked at several places (IQ initialization, adding items, updating items, deleting items, garbage collection). To properly solve this we need to remove the additionalWhereClause option and replace it with an easy to parse configuration. I call this a query builder and the idea is noted down in tx_solr_indexqueue_initializer_Abstract already:

tt_news {
    conditions {
        10 {
            field = pid
            value = 2,3,5
            condition = in / equals / notEquals / greaterThan / lessThan / greaterThanOrEqual / lessThanOrEqual
        }

        20 {
            field = ...
            value = ...
            condition = ...

            or {
                10 {
                    field = ...
                    value = ...
                    condition =  ...
                }

                20 {
                    field = ...
                    value = ...
                    condition = ...
                }
            }
        }
    }

    fields {
        // field mapping
    }
}