[LUCENE-2469] inconsistency in SolrParams.get()

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: core/other

Environment

all

• Lucene Fields: New
• Assignee: Unassigned
• Reporter: Frank Wesemann
• Created: 19/May/10 14:42
• Updated: 28/Aug/22 12:26

Description

The returned value from solrParams.get( key ) depends on the implementing class such that:

modifiableParams = new ModifiableSolrParams( req.getParams() );
assert modifiableParams.get("key").equals( req.getParams().get("key") );

fails for requests built from a SimpleRequestParser or StandardRequestParser where the parameter "key" was given, but empty ( e.g. localhost:8393/select/?key=&para1=val1&parm2=val2 ).

The reason is that oas.request.ServletSolrParams returns null for values with length() == 0,
but all other SolrParams implementations return the empty String.

This behaviour has also side effects on search components:
Most, if not all, standard search components check for something like

if (reg.getParams().getBool(myTriggerParameter, false) )

{ ...do what I am supposed to do... }

In case of ServletSolrParams getBool() returns the desired and expected "false", all other Implementations throw a "bad request" Exception.
One may argue that suppling a parameter with an empty value indeed is a malformed request, ...

Nonetheless I think, the above mentioned equality check should hold true for any request and any SolrParams.

Because I cannot oversee the implications, I currently don't have a better suggestion to achieve this, than
to make ServleSolrParams also return the empty String, which is in my opinion counter-intuitive and does not the right thing for the getBool(), getInt() etc. cases.