If I place the following code in the plugin fts_backend_xxx_update_build_more function (lucene, squat and xapian, as solr refuses to work properly on my setup)

        {
                char * s = i_strdup("EMPTY");
                if(data != NULL) { i_free(s); s = i_strndup(data,20); }
                i_info("fts_backend_update_build_more: data like '%s'",s);
                i_free(s);
        }

and if I send a PDF by email, the data shown in the log is "%PDF-1.7 "

so it does mean the decoder data is not properly transmitted to the plugin

Something is wrong in the data transmission

On 2021-02-09 11:58, John Fawcett wrote:

On 08/02/2021 23:05, Stuart Henderson wrote:

On 2021/02/08 21:33, Joan Moreau wrote:

Yes , once again : output of the decoder is fine, I also put log inide the dovecot core to
check whether data is properly transmitted, and result is that it is (i.e. dovecot core
receives the proper output of pdftotext via the decoder

Now, that data is the /not/ the one sent from dovecot core to the fts plugin (and this is the
same issue for solr and all other plugins)

Seems that something is different with your setup than John's and mine
then, as fts_solr rawlog (which is just the http request split into
.in and .out files) has the decoded file for us.

Did you try with the actual fts_solr plugin so it's a direct comparison
with what we see? There is no need for a real solr server, just point it
at any http server (or I guess netcat listening on a port will also do)
with

mail_plugins = fts fts_solr

plugin {
  fts_autoindex = yes
  fts = solr
  fts_solr = url=http://127.0.0.1:80/ rawlog_dir=/tmp/solr
}

If that is not showing decoded for you then I suppose there's some
problem on the way into/through fts. And if it does show as decoded
then perhaps fts_solr is doing something slightly different than the
places you're examining in fts and your plugin, and that might give
a point to work backwards from.

I'd also recommend Joan to look into some of the potential configuration
issues I mentioned in my first reply and if the problem persists, post
some clear evidence.

John