Revert "Add system check for missing database indexes" (#30909)

Gemfile

@@ -229,4 +229,3 @@ gem 'rubyzip', '~> 2.3'
 gem 'hcaptcha', '~> 7.1'
 
 gem 'mail', '~> 2.8'
-gem 'prism'

Gemfile.lock

@@ -600,7 +600,6 @@ GEM
       actionmailer (>= 3)
       net-smtp
       premailer (~> 1.7, >= 1.7.9)
-    prism (0.30.0)
     propshaft (0.9.0)
       actionpack (>= 7.0.0)
       activesupport (>= 7.0.0)
@@ -1004,7 +1003,6 @@ DEPENDENCIES
   pg (~> 1.5)
   pghero
   premailer-rails
-  prism
   propshaft
   public_suffix (~> 6.0)
   puma (~> 6.3)

app/lib/admin/db/schema_parser.rb

@@ -1,92 +0,0 @@
-# frozen_string_literal: true
-
-class Admin::Db::SchemaParser
-  class Index
-    attr_reader :name, :table_name, :columns, :options
-
-    def initialize(name:, table_name:, columns:, options:)
-      @name = name
-      @table_name = table_name
-      @columns = columns
-      @options = options
-    end
-  end
-
-  attr_reader :indexes_by_table
-
-  def initialize(source)
-    parse(source)
-  end
-
-  private
-
-  def parse(source)
-    @indexes_by_table = {}
-    queue = [Prism.parse(source).value]
-    while (node = queue.shift)
-      if node.type == :call_node && node.name == :create_table
-        parse_create_table(node)
-      elsif node.type == :call_node && node.name == :add_index
-        parse_add_index(node)
-      else
-        queue.concat(node.compact_child_nodes)
-      end
-    end
-  end
-
-  def parse_create_table(node)
-    table_name = parse_arguments(node).first
-    queue = node.compact_child_nodes
-    while (node = queue.shift)
-      if node.type == :call_node && node.name == :index
-        parse_index(node, table_name:)
-      else
-        queue.concat(node.compact_child_nodes)
-      end
-    end
-  end
-
-  def parse_index(node, table_name:)
-    arguments = parse_arguments(node)
-    save_index(
-      name: arguments.last[:name],
-      table_name: table_name,
-      columns: arguments.first,
-      options: arguments.last
-    )
-  end
-
-  def parse_add_index(node)
-    arguments = parse_arguments(node)
-    save_index(
-      name: arguments.last[:name],
-      table_name: arguments.first,
-      columns: arguments[1],
-      options: arguments.last
-    )
-  end
-
-  def parse_arguments(node)
-    node.arguments.arguments.map { |a| parse_argument(a) }
-  end
-
-  def parse_argument(argument)
-    case argument
-    when Prism::StringNode
-      argument.unescaped
-    when Prism::SymbolNode
-      argument.unescaped.to_sym
-    when Prism::ArrayNode
-      argument.elements.map { |e| parse_argument(e) }
-    when Prism::KeywordHashNode
-      argument.elements.to_h do |element|
-        [element.key.unescaped.to_sym, parse_argument(element.value)]
-      end
-    end
-  end
-
-  def save_index(name:, table_name:, columns:, options:)
-    @indexes_by_table[table_name] ||= []
-    @indexes_by_table[table_name] << Index.new(name:, table_name:, columns:, options:)
-  end
-end

app/lib/admin/system_check.rb

@@ -8,7 +8,6 @@ class Admin::SystemCheck
     Admin::SystemCheck::SidekiqProcessCheck,
     Admin::SystemCheck::RulesCheck,
     Admin::SystemCheck::ElasticsearchCheck,
-    Admin::SystemCheck::MissingIndexesCheck,
   ].freeze
 
   def self.perform(current_user)

app/lib/admin/system_check/missing_indexes_check.rb

@@ -1,36 +0,0 @@
-# frozen_string_literal: true
-
-class Admin::SystemCheck::MissingIndexesCheck < Admin::SystemCheck::BaseCheck
-  def skip?
-    !current_user.can?(:view_devops)
-  end
-
-  def pass?
-    missing_indexes.none?
-  end
-
-  def message
-    Admin::SystemCheck::Message.new(:missing_indexes_check, missing_indexes.join(', '))
-  end
-
-  private
-
-  def missing_indexes
-    @missing_indexes ||= begin
-      expected_indexes_by_table.flat_map do |table, indexes|
-        expected_indexes = indexes.map(&:name)
-        expected_indexes - existing_indexes_for(table)
-      end
-    end
-  end
-
-  def expected_indexes_by_table
-    schema_rb = Rails.root.join('db', 'schema.rb').read
-    schema_parser = Admin::Db::SchemaParser.new(schema_rb)
-    schema_parser.indexes_by_table
-  end
-
-  def existing_indexes_for(table)
-    ActiveRecord::Base.connection.indexes(table).map(&:name)
-  end
-end

config/locales/en.yml

@@ -862,8 +862,6 @@ en:
       elasticsearch_version_check:
         message_html: 'Incompatible Elasticsearch version: %{value}'
         version_comparison: Elasticsearch %{running_version} is running while %{required_version} is required
-      missing_indexes_check:
-        message_html: 'The following indexes are missing from the database and should be recreated: <code>%{value}</code>.<br> Missing indexes may lead to severely reduced performance and data inconsistencies.'
       rules_check:
         action: Manage server rules
         message_html: You haven't defined any server rules.

spec/lib/admin/db/schema_parser_spec.rb

@@ -1,49 +0,0 @@
-# frozen_string_literal: true
-
-require 'rails_helper'
-
-describe Admin::Db::SchemaParser do
-  let(:dummy_schema) do
-    <<~SCHEMA
-      # Comment
-      ActiveRecord::Schema[7.1].define(version: 23) do
-        create_table "people", force: :cascade do |t|
-          t.string "name"
-        end
-
-        create_table "posts", force: :cascade do |t|
-          t.string "title", null: false
-          t.bigint "size", null: false
-          t.string "description"
-          # t.index ["size", "title"], name: "index_posts_on_size_and_title"
-          t.index ["title"], name: "index_posts_on_title", unique: true
-          t.index ["size"], name: "index_posts_on_size"
-        end
-
-        # add_index "people", ["name"], name: "commented_out_index"
-        add_index "people", ["name"], name: "index_people_on_name"
-      end
-    SCHEMA
-  end
-  let(:schema_parser) { described_class.new(dummy_schema) }
-
-  describe '#indexes_by_table' do
-    subject { schema_parser.indexes_by_table }
-
-    it 'returns index info for all affected tables' do
-      expect(subject.keys).to match_array(%w(people posts))
-    end
-
-    it 'returns all index information for the `people` table' do
-      people_info = subject['people']
-      expect(people_info.map(&:name)).to contain_exactly('index_people_on_name')
-    end
-
-    it 'returns all index information for the `posts` table' do
-      posts_info = subject['posts']
-      expect(posts_info.map(&:name)).to contain_exactly(
-        'index_posts_on_title', 'index_posts_on_size'
-      )
-    end
-  end
-end

spec/lib/admin/system_check/missing_indexes_check_spec.rb

@@ -1,65 +0,0 @@
-# frozen_string_literal: true
-
-require 'rails_helper'
-
-describe Admin::SystemCheck::MissingIndexesCheck do
-  subject(:check) { described_class.new(user) }
-
-  let(:user) { Fabricate(:user) }
-  let(:schema_parser) do
-    instance_double(Admin::Db::SchemaParser, indexes_by_table: index_info)
-  end
-  let(:index_info) do
-    {
-      'users' => [instance_double(Admin::Db::SchemaParser::Index, name: 'index_users_on_profile_id')],
-      'posts' => [instance_double(Admin::Db::SchemaParser::Index, name: 'index_posts_on_user_id')],
-    }
-  end
-  let(:posts_indexes) { [] }
-  let(:users_indexes) { [] }
-
-  before do
-    allow(Admin::Db::SchemaParser).to receive(:new).and_return(schema_parser)
-    allow(ActiveRecord::Base.connection).to receive(:indexes).with('posts').and_return(posts_indexes)
-    allow(ActiveRecord::Base.connection).to receive(:indexes).with('users').and_return(users_indexes)
-  end
-
-  it_behaves_like 'a check available to devops users'
-
-  describe '#pass?' do
-    context 'when indexes are missing' do
-      let(:posts_indexes) do
-        [instance_double(ActiveRecord::ConnectionAdapters::IndexDefinition, name: 'index_posts_on_user_id')]
-      end
-
-      it 'returns false' do
-        expect(check.pass?).to be false
-      end
-    end
-
-    context 'when all expected indexes are present' do
-      let(:posts_indexes) do
-        [instance_double(ActiveRecord::ConnectionAdapters::IndexDefinition, name: 'index_posts_on_user_id')]
-      end
-      let(:users_indexes) do
-        [instance_double(ActiveRecord::ConnectionAdapters::IndexDefinition, name: 'index_users_on_profile_id')]
-      end
-
-      it 'returns true' do
-        expect(check.pass?).to be true
-      end
-    end
-  end
-
-  describe '#message' do
-    subject { check.message }
-
-    it 'sets the class name as the message key' do
-      expect(subject.key).to eq(:missing_indexes_check)
-    end
-
-    it 'sets a list of missing indexes as message value' do
-      expect(subject.value).to eq('index_users_on_profile_id, index_posts_on_user_id')
-    end
-  end
-end