Bug in scoreNodes function of streaming expressions?

[Pratik Patel]

Hello Everyone,

I am trying to execute following streaming expression with "scoreNodes"
function in it. This is taken from the documentation.

scoreNodes(top(n="50",
                   sort="count(*) desc",
                   nodes(baskets,
                         random(baskets, q="productID:ABC", fl="basketID",
rows="500"),
                         walk="basketID->basketID",
                         fq="-productID:ABC",
                         gather="productID",
                         count(*))))

I have ensured that I have the collection and data present for it.
Upon executing this, I am getting an error message as follows.

"No collection param specified on request and no default collection has
been set: []"

Upon digging into the source code I found that there is a possible bug in
ScoreNodesStream.java

StringBuilder instance is never appended any string and the block which
initializes collection, needs the length of that instance to be more than
zero. This condition will always be false and hence the collection will
never be set.

I checked this file in solr version 8.1 and that also has the same issue.
Is there any JIRA open for this or any patch available?

[image: image.png]

Thanks,
Pratik