Change Solr shema before DIH

Question

I try to change Solr schema before DIH to fit it to SQL query result. I use my custom proccesor and in init method i add new fields in schema:

@Override
public void init(Context context) {
    super.init(context);
    String mode = (String) context.getRequestParameters().get("command");
    if (mode.equals("full-import")) {
        Map<String, Object> row = this.nextRow();
        Set<String> fields = context.getSolrCore().getLatestSchema().getFields().keySet();
        IndexSchema schema = context.getSolrCore().getLatestSchema();

        Map<String, Object> fieldAttributes = new LinkedHashMap<>();
        fieldAttributes.put("stored", true);
        fieldAttributes.put("indexed", true);

        for (Map.Entry<String,Object> entry : row.entrySet()) {
            if (!fields.contains(entry.getKey())) {
                SchemaField schemaField = schema.newField(entry.getKey(), "string", fieldAttributes);
                schema = schema.addField(schemaField);
            }
        }

        context.getSolrCore().setLatestSchema(schema);
    }
    rowIterator = null;
}

All works, but import go by old schema (i had only 3 fields at start). I see changes on schema after first import. If i restart import again - all works good, and i see all my new fields with their values.

How to point Solr to the new schema and do not restart import?

UPDATE:

I extend SqlEntityProcessor

    public class KinefProccessor extends SqlEntityProcessor {
    
        @Override
        public void init(Context context) {
            super.init(context);
            String mode = (String) context.getRequestParameters().get("command");
....
....

And my config:

<dataConfig>
    <dataSource driver="org.postgresql.Driver" url="jdbc:postgresql://*******" user="***" password="***" />
    <document>
        <entity name="item" query="****"  processor = "KinefProccessor">
            <field column="v.id" name="id" />
        </entity>
    </document>
</dataConfig>