Enable advanced search + support its use of Solr's JSON Query DSL

app/components/um_blacklight_search_bar_component.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+class UmBlacklightSearchBarComponent < Blacklight::SearchBarComponent
+  def advanced_search_enabled?
+    false
+  end
+end

app/components/um_search_bar_component.html.erb

@@ -0,0 +1,27 @@
+<%= render(UmBlacklightSearchBarComponent.new(
+  **@kwargs,
+  params: @params.merge(f: (@params[:f] || {}).except(:collection)),
+  q: @q,
+  search_field: @search_field)) do |c| %>
+
+  <% c.with_before_input_group do %>
+    <div class="input-group within-collection-dropdown">
+      <label class="input-group-text" for="within_collection">
+        <%= t('arclight.within_collection_dropdown.label_html') %>
+      </label>
+      <%= select_tag ('f[collection][]' if collection_name.present?), within_collection_options, id: 'within_collection', class: 'form-select search-field rounded-end' %>
+    </div>
+  <% end %>
+
+  <% c.with_prepend do %>
+    <%= prepend %>
+  <% end %>
+
+  <% c.with_append do %>
+    <%= append %>
+  <% end if append? %>
+
+  <% c.with_search_button do %>
+    <%= search_button %>
+  <% end if respond_to?(:search_button?) && search_button? # only BL8 has this option %>
+<% end %>

app/components/um_search_bar_component.rb

@@ -0,0 +1,4 @@
+# frozen_string_literal: true
+
+class UmSearchBarComponent < Arclight::SearchBarComponent
+end

app/controllers/catalog_controller.rb

@@ -3,6 +3,7 @@
 require_relative "../components/um_access_component"
 require_relative "../components/um_constraints_component"
 require_relative "../components/um_document_component"
+require_relative "../components/um_search_bar_component"
 require_relative "../components/um_search_result_component"
 
 # Blacklight controller that handles searches and document requests
@@ -75,7 +76,7 @@ class CatalogController < ApplicationController
     config.index.group_component = Arclight::GroupComponent
     config.index.constraints_component = UmConstraintsComponent
     config.index.document_presenter_class = Arclight::IndexPresenter
-    config.index.search_bar_component = Arclight::SearchBarComponent
+    config.index.search_bar_component = UmSearchBarComponent
     # config.index.thumbnail_field = 'thumbnail_path_ss'
 
     # solr field configuration for document/show views
@@ -209,61 +210,70 @@ class CatalogController < ApplicationController
     # since we aren't specifying it otherwise.
     config.add_search_field "all_fields", label: "All Fields" do |field|
       field.include_in_simple_select = true
+      field.clause_params = { edismax: {} }
     end
 
     config.add_search_field "within_collection" do |field|
       field.include_in_simple_select = false
       field.solr_parameters = {
         fq: "-level_ssim:Collection"
       }
+      field.include_in_advanced_search = false
     end
 
     # Field-based searches. We have registered handlers in the Solr configuration
     # so we have Blacklight use the `qt` parameter to invoke them
     config.add_search_field "keyword", label: "Keyword" do |field|
-      field.qt = "search" # default
+      field.qt = "search"
+      field.clause_params = { edismax: {} }
     end
     config.add_search_field "name", label: "Name" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_name}",
         pf:  "${pf_name}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
     config.add_search_field "place", label: "Place" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_place}",
         pf:  "${pf_place}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
     config.add_search_field "subject", label: "Subject" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_subject}",
         pf:  "${pf_subject}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
     config.add_search_field "title", label: "Title" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_title}",
         pf:  "${pf_title}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
     config.add_search_field "container", label: "Container" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_container}",
         pf:  "${pf_container}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
     config.add_search_field "identifier", label: "Identifier" do |field|
       field.qt = "search"
       field.solr_parameters = {
         qf:  "${qf_identifier}",
         pf:  "${pf_identifier}"
       }
+      field.clause_params = { edismax: field.solr_parameters.dup }
     end
 
     # These are the parameters passed through in search_state.params_for_search
@@ -449,5 +459,8 @@ class CatalogController < ApplicationController
 
     # Group header values
     config.add_group_header_field "abstract_or_scope", accessor: true, truncate: true, helper_method: :render_html_tags
+
+    # Advanced search
+    config.advanced_search.enabled = true
   end
 end

app/helpers/catalog_helper.rb

@@ -2,6 +2,20 @@ module CatalogHelper
   include Blacklight::CatalogHelperBehavior
 
   def has_no_query
-    request.path == "/" && params[:q].blank? && params[:f].blank?
+    request.path == "/" &&
+      params[:q].blank? &&
+      params[:f].blank? &&
+      !advanced_search_clauses?
+  end
+
+  private
+
+  # Advanced search sends `clause[...][query]` params instead of `q`.
+  def advanced_search_clauses?
+    clauses = params[:clause]
+    return false if clauses.blank?
+
+    values = clauses.respond_to?(:values) ? clauses.values : clauses
+    values.any? { |clause| clause[:query].present? }
   end
 end

app/views/catalog/_home.html.erb

@@ -16,7 +16,6 @@
 
       <%= render(blacklight_config.view_config(document_index_view_type).search_bar_component.new(
         url: search_action_url,
-        advanced_search_url: search_action_url(action: 'advanced_search'),
         params: search_state.params_for_search.except(:qt),
         autocomplete_path: search_action_path(action: :suggest))) %>
 
@@ -25,6 +24,13 @@
           <%= link_to t('um_arclight.home.browse_all'), arclight_engine.collections_path %>
         </div>
 
+        <div class="search-extra-controls flex-fill">
+          <div class="input-group">
+            <%= link_to "Advanced Search",
+                        search_action_path(action: :advanced_search),
+                        class: "advanced_search" %>
+          </div>
+        </div>
       </div>
 
       <a class="d-flex align-items-center mt-4 mb-3" href="/repositories">

solr/conf/solrconfig.xml

@@ -206,6 +206,109 @@
     </arr>
   </requestHandler>
 
+  <!-- Advanced search handler for Blacklight's JSON Query DSL (json_solr_path
+     defaults to 'advanced'). Mirrors the query-parsing defaults of the
+     "search" handler so empty edismax clauses and ${qf_*}/${pf_*} macros
+     resolve identically to a normal search. -->
+  <requestHandler name="/advanced" class="solr.SearchHandler">
+    <lst name="defaults">
+      <str name="defType">edismax</str>
+      <str name="echoParams">explicit</str>
+      <int name="rows">10</int>
+      <str name="q.alt">*:*</str>
+
+      <str name="mm">4&lt;90%</str>
+
+      <str name="qf">
+        collection_title_tesim^150
+        title_tesim^100
+        normalized_title_teim^100
+        unitid_identifier_match^40
+        name_teim^10
+        place_teim^10
+        subject_teim^2
+        id
+        ead_ssi
+        ref_ssm
+        unitid_ssm
+        container_teim
+        parent_unittitles_tesim
+        text
+      </str>
+      <str name="pf">
+        collection_title_tesim^300
+        title_tesim^200
+        normalized_title_teim^200
+        unitid_identifier_match^80
+        name_teim^20
+        place_teim^20
+        subject_teim^5
+        id^2
+        ead_ssi^2
+        ref_ssm^2
+        unitid_ssm^2
+        container_teim^2
+        parent_unittitles_tesim^2
+        text^2
+      </str>
+
+      <str name="qf_container">
+        container_teim
+      </str>
+      <str name="pf_container">
+        container_teim^2
+      </str>
+      <str name="qf_identifier">
+        id
+        ead_ssi
+        ref_ssm
+        unitid_ssm
+        unitid_identifier_match
+      </str>
+      <str name="pf_identifier">
+        id^2
+        ead_ssi^2
+        ref_ssm^2
+        unitid_ssm^2
+        unitid_identifier_match^2
+      </str>
+      <str name="qf_name">
+        name_teim
+      </str>
+      <str name="pf_name">
+        name_teim^2
+      </str>
+      <str name="qf_place">
+        place_teim
+      </str>
+      <str name="pf_place">
+        place_teim^2
+      </str>
+      <str name="qf_subject">
+        subject_teim
+      </str>
+      <str name="pf_subject">
+        subject_teim^2
+      </str>
+      <str name="qf_title">
+        title_tesim
+        normalized_title_teim
+      </str>
+      <str name="pf_title">
+        title_tesim^2
+        normalized_title_teim^2
+      </str>
+
+      <int name="ps">3</int>
+      <float name="tie">0.01</float>
+
+      <str name="fl">*</str>
+    </lst>
+    <arr name="last-components">
+      <str>spellcheck</str>
+    </arr>
+  </requestHandler>
+
   <!-- for requests to get a single document; use id=666 instead of q=id:666 -->
   <requestHandler name="document" class="solr.SearchHandler" >
     <lst name="defaults">