"Cannot add array to BooleanQuery" error with ferret on rails

Question

I'm trying to get a simple search form working in my RoR site. I've got the following code:

(in note_controller.rb)

  def search
    @results = Note.find_with_ferret(params[:term]).sort_by(&:ferret_rank)

    respond_to do |format|
      format.html
      format.xml { render :xml => @nootes }
    end
  end

(in note.rb)

class Note < ActiveRecord::Base
  acts_as_ferret :fields => [ :title, :body ]
end

(in index.html.erb)

<%= form_tag :action => 'search'%>
<%= text_field 'term', nil  %>
  <%= submit_tag 'Search' %>
</form>

(in search.html.erb)

<h1><%= pluralize(@results.size, 'result') %></h1>

<ul>
<% for result in @results %>
  <li><%= result.ferret_score %>: <%= link_to result.tile, result %></li>
<% end %>
</ul>

As you can hopefully see from the above I've got a model which I've told to acts_as_ferret. I've then got a search action in my controller, which tries to render to the search.html.erb view. I've got a form in the index view which does a search. However, when I run this I get the following error:

Cannot add Array to a BooleanQuery

I guess I'm doing something wrong with my form so that ferret is getting the wrong data somehow. Is the form_tag thing I've done the right way to do it? Any help would be much appreciated.

Update:

Below is the only bit I can seem to extract from the log. I'm using Heroku and it doesn't seem to give quite the stardard log files. Hope this is helpful.

Processing NotesController#search (for 152.78.202.74, 127.0.0.1 at 2008-10-25 07:32:23)
[POST] Session ID: BAh7BzoMY3NyZl9pZCIlZmEyMzcxZTdlYTUyODRkNzlmMzdjZWJlOGNlOGYz M2UiCmZsYXNoSUM6J0FjdGlvbkNvbnRyb2xsZXI6OkZsYXNoOjpGbGFzaEhh c2h7AAY6CkB1c2VkewA=--450f51b45e38cba302e8ac6bd9b03c7ae79981e9
Parameters: {"commit"=>"Search", "term"=>["wheelbarrow"], "authenticity_token"=>"1879a835ded87e7a28861725ec668b690de6b7f5", "action"=>"search", "controller"=>"notes"}
configured index for class Note: {
    :index_dir=>"/mnt/home/userapps/38385/index/development/note",
    :mysql_fast_batches=>true, :name=>:note, :single_index=>false,
    :index_base_dir=>"/mnt/home/userapps/38385/index/development/note",
    :reindex_batch_size=>1000,
    :registered_models=>[Note(id: integer, title: string, body: text, created_at: datetime, updated_at: datetime)],
    :ferret=>{:dir=>#,
    :key=>[:id, :class_name],
    :or_default=>false,
    :handle_parse_errors=>true,
    :auto_flush=>true,
    :create_if_missing=>true,
    :path=>"/mnt/home/userapps/38385/index/development/note",
    :default_field=>[:title, :body],
    :analyzer=>#,
    :lock_retry_time=>2},
    :ferret_fields=>{:title=>{:via=>:title, :term_vector=>:with_positions_offsets, :boost=>1.0, :store=>:no, :highlight=>:yes, :index=>:yes},
    :body=>{:via=>:body, :term_vector=>:with_positions_offsets, :boost=>1.0, :store=>:no, :highlight=>:yes, :index=>:yes}},
    :fields=>[:title, :body],
    :raise_drb_errors=>false,
    :user_default_field=>nil,
    :enabled=>true}

ArgumentError (Cannot add Array to a BooleanQuery): /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:124:in `add_query'
    /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:124:in `scope_query_to_models'
    /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:102:in `find_ids'
    /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:85:in `find_id_model_arrays'
    /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:41:in `ar_find'
    /vendor/plugins/acts_as_ferret/lib/ferret_find_methods.rb:12:in `find_records'
    /vendor/plugins/acts_as_ferret/lib/acts_as_ferret.rb:342:in `find'
    /vendor/plugins/acts_as_ferret/lib/class_methods.rb:155:in `find_with_ferret'
    /app/controllers/notes_controller.rb:14:in `search'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/base.rb:1162:in `send'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/base.rb:1162:in `perform_action_without_filters'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/filters.rb:580:in `call_filters'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/filters.rb:573:in `perform_action_without_benchmark'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue_without_timeout'
    /usr/lib/ruby/1.8/benchmark.rb:293:in `measure'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/benchmarking.rb:68:in `perform_action_without_rescue_without_timeout'
    /home/userapps_plugins/preload/request_timeout/lib/request_timeout.rb:9:in `perform_action_without_rescue'
    /usr/lib/ruby/1.8/timeout.rb:48:in `timeout'
    /home/userapps_plugins/preload/request_timeout/lib/request_timeout.rb:8:in `perform_action_without_rescue'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/rescue.rb:201:in `perform_action_without_caching'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/caching/sql_cache.rb:13:in `perform_action'
    /usr/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/connection_adapters/abstract/query_cache.rb:33:in `cache'
    /usr/lib/ruby/gems/1.8/gems/activerecord-2.1.0/lib/active_record/query_cache.rb:8:in `cache'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/caching/sql_cache.rb:12:in `perform_action'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/base.rb:529:in `send'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/base.rb:529:in `process_without_filters'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/filters.rb:569:in `process_without_session_management_support'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/session_management.rb:130:in `process'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/base.rb:389:in `process'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/dispatcher.rb:149:in `handle_request'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/dispatcher.rb:107:in `dispatch'
    /usr/lib/ruby/1.8/thread.rb:135:in `synchronize'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/dispatcher.rb:104:in `dispatch'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/dispatcher.rb:120:in `dispatch_cgi'
    /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/dispatcher.rb:35:in `dispatch'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/rack/adapter/rails.rb:54:in `serve_rails'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/rack/adapter/rails.rb:74:in `call'
    /home/heroku_rack/lib/toolbar.rb:16:in `call'
    /usr/lib/ruby/gems/1.8/gems/rack-0.4.0/lib/rack/urlmap.rb:42:in `call'
    /usr/lib/ruby/gems/1.8/gems/rack-0.4.0/lib/rack/urlmap.rb:35:in `each'
    /usr/lib/ruby/gems/1.8/gems/rack-0.4.0/lib/rack/urlmap.rb:35:in `call'
    /usr/lib/ruby/gems/1.8/gems/rack-0.4.0/lib/rack/builder.rb:53:in `call'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/connection.rb:59:in `pre_process'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/connection.rb:50:in `process'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/connection.rb:35:in `receive_data'
    /usr/lib/ruby/gems/1.8/gems/eventmachine-0.12.0/lib/eventmachine.rb:224:in `run_machine'
    /usr/lib/ruby/gems/1.8/gems/eventmachine-0.12.0/lib/eventmachine.rb:224:in `run'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/backends/base.rb:45:in `start'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/server.rb:146:in `start'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/controllers/controller.rb:79:in `start'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/runner.rb:166:in `send'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/runner.rb:166:in `run_command'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/lib/thin/runner.rb:136:in `run!'
    /usr/lib/ruby/gems/1.8/gems/thin-0.8.2/bin/thin:6 /usr/bin/thin:19:in `load'
    /usr/bin/thin:19 Rendering /usr/lib/ruby/gems/1.8/gems/actionpack-2.1.0/lib/action_controller/templates/res

Answer 1

I can't recall ever seeing that ferret error. There's two basic diagnostics: go into script/console, and do

Notes.find_with_ferret("some term that should be in index") 

And then see what happens when you remove the indexes' directory (/appname/index/development), do another find_with_ferret to force reindex?

Background info: are "title" and "body" columns in table, or calculated in instance method, or children from e.g. has_many? If fields in the table, what column types are "title" and "body" declared at in the migration, and what kind fo mySQL column types are they?

Also usually helpful to include your O/S, the versions of ruby, rails, ferret and a_a_f you're using.

Answer 2

I've removed the index directory, and it seems to have regenerated itself but now my searches on the console are giving no results. Before I deleted the index directory I got results on the console, but not when used from the form in my app.

Title and Body are both columns in my MySQL table. They were created using Rails migrations as type string and text respectively.

I'm running on Heroku - so I'm not entirely sure what OS (probably linux) or versions though I know it is at least rails 2.1. I also can't seem to find a version number for AAF - but I guess it's relatively recent.

Sorry I can't be more help - is what I've said any use?

Robin