RSpec matchers for database queries.
Add this line to your application's Gemfile, preferably in your test group:
gem 'db-query-matchers'And then execute:
bundleOr install it yourself as:
gem install db-query-matchersdescribe 'MyCode' do
context 'when we expect no queries' do
it 'does not make database queries' do
expect { subject.make_no_queries }.to_not make_database_queries
end
end
context 'when we expect queries' do
it 'makes database queries' do
expect { subject.make_some_queries }.to make_database_queries
end
end
context 'when we expect exactly 1 query' do
it 'makes database queries' do
expect { subject.make_one_query }.to make_database_queries(count: 1)
end
end
context 'when we expect max 3 queries' do
it 'makes database queries' do
expect { subject.make_several_queries }.to make_database_queries(count: 0..3)
end
end
context 'when we expect a possible range of queries' do
it 'makes database queries' do
expect { subject.make_several_queries }.to make_database_queries(count: 3..5)
end
end
context 'when we only care about manipulative queries (INSERT, UPDATE, DELETE)' do
it 'makes a destructive database query' do
expect { subject.make_one_query }.to make_database_queries(manipulative: true)
end
end
context 'when we only care about queries matching a certain pattern' do
it 'makes a destructive database query' do
expect { subject.make_special_queries }.to make_database_queries(matching: 'DELETE * FROM')
end
it 'makes a destructive database query matched with a regexp' do
expect { subject.make_special_queries }.to make_database_queries(matching: /DELETE/)
end
end
endTo exclude certain types of queries from being counted, specify an
ignores configuration consisting of an array of regular expressions. If
a query matches one of the patterns in this array, it will not be
counted in the make_database_queries matcher.
To exclude SCHEMA queries, add schemaless to the configuration. This will
help avoid failing specs due to ActiveRecord load order.
DBQueryMatchers.configure do |config|
config.ignores = [/SHOW TABLES LIKE/]
config.schemaless = true
# the payload argument is described here:
# http://edgeguides.rubyonrails.org/active_support_instrumentation.html#sql-active-record
config.on_query_counted do |payload|
# do something arbitrary with the query
end
end