Fairly certain you aren't overridding getExtraRequestFields, so when your
DocTransformer is evaluated it can'd find the field you want it to
transform.
By default, the ResponseWriters don't provide any fields that aren't
explicitly requested by the user, or specified as "extra" by the
DocTransformer.
IIUC you want the stored value of the "minhash" field to be available to
you, but the response writer code doesn't know that -- it just knows you
want "minhash" to be the output respons key for the "[binstr]"
transformer.
Take a look at RawValueTransformerFactory as an example to borrow from.
: Date: Wed, 14 Dec 2016 21:55:26 +0000
: From: Markus Jelsma <markus.jel...@openindex.io>
: Reply-To: solr-user@lucene.apache.org
: To: solr-user <solr-user@lucene.apache.org>
: Subject: DocTransformer not always working
:
: Hello - I just spotted an oddity with all two custom DocTransformers we
sometimes use on Solr 6.3.0. This particular transformer in the example just
transforms a long (or int) into a sequence of bits. I just use it as an
convenience to compare minhashes with my eyeballs. First example is very
straightforward, fl=minhash:[binstr], show only the minhash field, but as a bit
sequence.
:
:
solr/search/select?omitHeader=true&wt=json&indent=true&rows=1&sort=id%20asc&q=*:*&fl=minhash:[binstr]
: {
: "response":{"numFound":96933,"start":0,"docs":[
: {}]
: }}
:
: The document is empty! This also happens with another transformer. The next
example i also request the lang field:
:
: solr/search/select?omitHeader=true&wt=json&indent=true&rows=1&sort=id
asc&q=*:*&fl=lang,minhash:[binstr]
: {
: "response":{"numFound":96933,"start":0,"docs":[
: {
: "lang":"nl"}]
: }}
:
: Ok, at least i now get the lang field, but the transformed minhash is nowhere
to be seen. In the next example i request all fields and the transformed
minhash:
:
:
/solr/search/select?omitHeader=true&wt=json&indent=true&rows=1&sort=id%20asc&q=*:*&fl=*,minhash:[binstr]
: {
: "response":{"numFound":96933,"start":0,"docs":[
: {
:
"minhash":"1110110101111010100011010010101111100001110110010111101101111010",
: ...other fields here
: "_version_":1553728923368423424}]
: }}
:
: So it seems that right now, i can only use a transformer properly if i
request all fields. I believe it used to work with all three examples just as
you would expect. But since i haven't used transformers for a while, i don't
know at which version it stopped working like that (if it ever did of course :)
:
: Did i mess something up or did a bug creep on me?
:
: Thanks,
: Markus
:
-Hoss
http://www.lucidworks.com/
