Rails: Metasearch breaks when scoped and paginated?

Question

I have a searchable set of photos, and I want to limit the results for the index page to ones that are public (ie don't belong to a private collection, aka. :collection_id=>nil).

I have the following scope in my model:

scope :community, where(:collection_id => nil)

I have the following in my controller:

def index
  @search = Photo.community.search(params[:search])
  @photos = @search.page(params[:page]).per(20)
end

I'm using Kaminari to paginate the results.

When I search photos unscoped (ie Photo.search(params[:search])) it works fine. However, when I search for photos using this scope pagination breaks the search. The first page shows up correctly, but when I go to another page there are no results. To test this locally I changed pagination to 1 per page and still no matter what I search for any pages after the first page show no results even though the paginator indicates that there are many more pages of results.

I have no idea how to debug and fix this, and I would really use some help. Here's the SQL from the development log:

For a normal load of the index page (no search):

Started GET "/photos" for 127.0.0.1 at 2011-04-28 11:58:51 -0500
  Processing by PhotosController#index as HTML
  SQL (0.4ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (0.3ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'
  User Load (0.7ms)  SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1
  Context Load (0.3ms)  SELECT "contexts".* FROM "contexts" ORDER BY "contexts"."display_order" ASC
  Focus Load (0.3ms)  SELECT "focus".* FROM "focus" ORDER BY "focus"."display_order" ASC
  LandUse Load (0.3ms)  SELECT "land_uses".* FROM "land_uses" ORDER BY "land_uses"."display_order" ASC
Rendered static/_help-context.html.haml (4.5ms)
Rendered static/_help-focus.html.haml (3.1ms)
Rendered photos/_search.html.haml (304.9ms)
  SQL (0.5ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL LIMIT 1 OFFSET 0
  Photo Load (1.0ms)  SELECT "photos".* FROM "photos" WHERE "photos"."collection_id" IS NULL LIMIT 1 OFFSET 0
  Attachment Load (0.2ms)  SELECT "attachments".* FROM "attachments" WHERE ("attachments".photo_id = 1)
  User Load (1.0ms)  SELECT "users".* FROM "users" WHERE ("users"."id" = 1)
  Profile Load (1.7ms)  SELECT "profiles".* FROM "profiles" WHERE ("profiles".user_id = 1) LIMIT 1
  Context Load (0.2ms)  SELECT "contexts".* FROM "contexts" WHERE "contexts"."id" = 6 ORDER BY "contexts"."display_order" ASC LIMIT 1
  Focus Load (0.1ms)  SELECT "focus".* FROM "focus" WHERE "focus"."id" = 2 ORDER BY "focus"."display_order" ASC LIMIT 1
  LandUse Load (0.2ms)  SELECT * FROM "land_uses" INNER JOIN "land_uses_photos" ON "land_uses".id = "land_uses_photos".land_use_id WHERE ("land_uses_photos".photo_id = 1 ) ORDER BY "land_uses"."display_order" ASC
Rendered photos/_photo_tiles.html.haml (62.2ms)
  SQL (0.2ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL
Rendered shared/_feedback.html.haml (1.5ms)
  Role Load (0.5ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
  CACHE (0.0ms)  SELECT "profiles".* FROM "profiles" WHERE ("profiles".user_id = 1) LIMIT 1
  CACHE (0.0ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
Rendered shared/_menu.html.haml (177.6ms)
Rendered shared/_footer.html.haml (2.7ms)
Rendered photos/index.html.haml within layouts/application (897.1ms)
Completed 200 OK in 1158ms (Views: 912.2ms | ActiveRecord: 8.2ms)

For the first page of a search (works correctly):

Started GET "/photos?utf8=%E2%9C%93&search%5Bcontext_id_in%5D%5B%5D=6&search%5Btagged_with%5D=&search%5Btext_contains%5D=&search%5Bnear%5D%5B%5D=&search%5Bnear%5D%5B%5D=100&commit=Search" for 127.0.0.1 at 2011-04-28 12:00:39 -0500
  Processing by PhotosController#index as HTML
  Parameters: {"utf8"=>"✓", "search"=>{"context_id_in"=>["6"], "tagged_with"=>"", "text_contains"=>"", "near"=>["", "100"]}, "commit"=>"Search"}
  SQL (0.4ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (0.3ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'
  User Load (0.6ms)  SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1
  Context Load (0.4ms)  SELECT "contexts".* FROM "contexts" ORDER BY "contexts"."display_order" ASC
  Focus Load (0.3ms)  SELECT "focus".* FROM "focus" ORDER BY "focus"."display_order" ASC
  LandUse Load (0.4ms)  SELECT "land_uses".* FROM "land_uses" ORDER BY "land_uses"."display_order" ASC
Rendered static/_help-context.html.haml (4.6ms)
Rendered static/_help-focus.html.haml (3.1ms)
Rendered photos/_search.html.haml (161.0ms)
  SQL (0.4ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL AND "photos"."context_id" IN (6) LIMIT 1 OFFSET 0
  Photo Load (0.7ms)  SELECT "photos".* FROM "photos" WHERE "photos"."collection_id" IS NULL AND "photos"."context_id" IN (6) LIMIT 1 OFFSET 0
  Attachment Load (0.2ms)  SELECT "attachments".* FROM "attachments" WHERE ("attachments".photo_id = 1)
  User Load (0.9ms)  SELECT "users".* FROM "users" WHERE ("users"."id" = 1)
  Profile Load (1.9ms)  SELECT "profiles".* FROM "profiles" WHERE ("profiles".user_id = 1) LIMIT 1
  Context Load (0.2ms)  SELECT "contexts".* FROM "contexts" WHERE "contexts"."id" = 6 ORDER BY "contexts"."display_order" ASC LIMIT 1
  Focus Load (0.2ms)  SELECT "focus".* FROM "focus" WHERE "focus"."id" = 2 ORDER BY "focus"."display_order" ASC LIMIT 1
  LandUse Load (0.2ms)  SELECT * FROM "land_uses" INNER JOIN "land_uses_photos" ON "land_uses".id = "land_uses_photos".land_use_id WHERE ("land_uses_photos".photo_id = 1 ) ORDER BY "land_uses"."display_order" ASC
Rendered photos/_photo_tiles.html.haml (204.2ms)
  SQL (0.3ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL AND "photos"."context_id" IN (6)
Rendered shared/_feedback.html.haml (1.3ms)
  Role Load (0.4ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
  CACHE (0.0ms)  SELECT "profiles".* FROM "profiles" WHERE ("profiles".user_id = 1) LIMIT 1
  CACHE (0.0ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
Rendered shared/_menu.html.haml (35.5ms)
Rendered shared/_footer.html.haml (2.9ms)
Rendered photos/index.html.haml within layouts/application (729.3ms)
Completed 200 OK in 990ms (Views: 728.5ms | ActiveRecord: 7.7ms)

For the second page of a search (shows no results even though they exist):

Started GET "/photos?commit=Search&page=2&search[context_id_in][]=6&search[near][]=&search[near][]=100&search[tagged_with]=&search[text_contains]=&utf8=%E2%9C%93" for 127.0.0.1 at 2011-04-28 12:01:33 -0500
  Processing by PhotosController#index as HTML
  Parameters: {"commit"=>"Search", "page"=>"2", "search"=>{"context_id_in"=>["6"], "near"=>["", "100"], "tagged_with"=>"", "text_contains"=>""}, "utf8"=>"✓"}
  SQL (0.4ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'

  SQL (0.3ms)   SELECT name
 FROM sqlite_master
 WHERE type = 'table' AND NOT name = 'sqlite_sequence'
  User Load (0.7ms)  SELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1
  Context Load (0.3ms)  SELECT "contexts".* FROM "contexts" ORDER BY "contexts"."display_order" ASC
  Focus Load (0.3ms)  SELECT "focus".* FROM "focus" ORDER BY "focus"."display_order" ASC
  LandUse Load (0.3ms)  SELECT "land_uses".* FROM "land_uses" ORDER BY "land_uses"."display_order" ASC
Rendered static/_help-context.html.haml (4.9ms)
Rendered static/_help-focus.html.haml (3.4ms)
Rendered photos/_search.html.haml (307.8ms)
  SQL (0.3ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL AND "photos"."context_id" IN (6) LIMIT 1 OFFSET 1
  SQL (0.3ms)  SELECT COUNT(DISTINCT "photos"."id") FROM "photos" LEFT OUTER JOIN "attachments" ON "attachments"."photo_id" = "photos"."id" LEFT OUTER JOIN "collections" ON "collections"."id" = "photos"."collection_id" WHERE "photos"."collection_id" IS NULL AND "photos"."context_id" IN (6)
Rendered shared/_feedback.html.haml (1.5ms)
  Role Load (0.4ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
  Profile Load (1.6ms)  SELECT "profiles".* FROM "profiles" WHERE ("profiles".user_id = 1) LIMIT 1
  CACHE (0.0ms)  SELECT "roles".* FROM "roles" INNER JOIN "roles_users" ON "roles".id = "roles_users".role_id WHERE "roles"."name" = 'admin' AND ("roles_users".user_id = 1 ) LIMIT 1
Rendered shared/_menu.html.haml (209.5ms)
Rendered shared/_footer.html.haml (2.7ms)
Rendered photos/index.html.haml within layouts/application (822.3ms)
Completed 200 OK in 934ms (Views: 823.7ms | ActiveRecord: 5.1ms)

Again note that in the logs above I have set pagination to 1 per page so I can see if the paginator is showing the right number of results, and it is. For instance, if I search for something I know there are 3 matches for at one per page the paginator says there are three pages of results, however pages 2 and 3 are blank.

I am completely stumped, any help would be much appreciated.

Answer 1

Try adding your scope as a search method.

class Photo < ActiveRecord::Base
  scope :community, where(:collection_id => nil)
  search_methods :community
end

class PhotosController < ActiveRecord::Base
  def index
    params[:search][:community] => true
    @search = Photo.search(params[:search])
    @photos = @search.page(params[:page]).per(20)
  end
end

I don't use kaminari myself so I can't say for sure, but I know that the MetaSearch docs say to use search_methods in order to use scopes in searches.

Answer 2

it works for me with the current latest gems (meta_search 1.0.4, kaminari 0.12.4).

As the author of Kaminari gem, I suppose some older versions of Kaminari possibly does not work with meta_search. I actually fixed several bugs that may cause this kind of problem.

So, can you please upgrade your Kaminari gem and try again?