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|
require "cases/helper"
module ActiveRecord
module ConnectionAdapters
class ConnectionPoolTest < ActiveRecord::TestCase
attr_reader :pool
def setup
super
# Keep a duplicate pool so we do not bother others
@pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
if in_memory_db?
# Separate connections to an in-memory database create an entirely new database,
# with an empty schema etc, so we just stub out this schema on the fly.
@pool.with_connection do |connection|
connection.create_table :posts do |t|
t.integer :cololumn
end
end
end
end
def teardown
super
@pool.disconnect!
end
def active_connections(pool)
pool.connections.find_all(&:in_use?)
end
def test_checkout_after_close
connection = pool.connection
assert connection.in_use?
connection.close
assert !connection.in_use?
assert pool.connection.in_use?
end
def test_released_connection_moves_between_threads
thread_conn = nil
Thread.new {
pool.with_connection do |conn|
thread_conn = conn
end
}.join
assert thread_conn
Thread.new {
pool.with_connection do |conn|
assert_equal thread_conn, conn
end
}.join
end
def test_with_connection
assert_equal 0, active_connections(pool).size
main_thread = pool.connection
assert_equal 1, active_connections(pool).size
Thread.new {
pool.with_connection do |conn|
assert conn
assert_equal 2, active_connections(pool).size
end
assert_equal 1, active_connections(pool).size
}.join
main_thread.close
assert_equal 0, active_connections(pool).size
end
def test_active_connection_in_use
assert !pool.active_connection?
main_thread = pool.connection
assert pool.active_connection?
main_thread.close
assert !pool.active_connection?
end
def test_full_pool_exception
assert_raises(PoolFullError) do
(@pool.size + 1).times do
@pool.checkout
end
end
end
def test_full_pool_blocks
cs = @pool.size.times.map { @pool.checkout }
t = Thread.new { @pool.checkout }
# make sure our thread is in the timeout section
Thread.pass until t.status == "sleep"
connection = cs.first
connection.close
assert_equal connection, t.join.value
end
def test_removing_releases_latch
cs = @pool.size.times.map { @pool.checkout }
t = Thread.new { @pool.checkout }
# make sure our thread is in the timeout section
Thread.pass until t.status == "sleep"
connection = cs.first
@pool.remove connection
assert_respond_to t.join.value, :execute
end
def test_reap_and_active
@pool.checkout
@pool.checkout
@pool.checkout
@pool.dead_connection_timeout = 0
connections = @pool.connections.dup
@pool.reap
assert_equal connections.length, @pool.connections.length
end
def test_reap_inactive
@pool.checkout
@pool.checkout
@pool.checkout
@pool.dead_connection_timeout = 0
connections = @pool.connections.dup
connections.each do |conn|
conn.extend(Module.new { def active?; false; end; })
end
@pool.reap
assert_equal 0, @pool.connections.length
ensure
connections.each(&:close)
end
def test_remove_connection
conn = @pool.checkout
assert conn.in_use?
length = @pool.connections.length
@pool.remove conn
assert conn.in_use?
assert_equal(length - 1, @pool.connections.length)
ensure
conn.close
end
def test_remove_connection_for_thread
conn = @pool.connection
@pool.remove conn
assert_not_equal(conn, @pool.connection)
ensure
conn.close if conn
end
def test_active_connection?
assert !@pool.active_connection?
assert @pool.connection
assert @pool.active_connection?
@pool.release_connection
assert !@pool.active_connection?
end
def test_checkout_behaviour
pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
connection = pool.connection
assert_not_nil connection
threads = []
4.times do |i|
threads << Thread.new(i) do |pool_count|
connection = pool.connection
assert_not_nil connection
connection.close
end
end
threads.each(&:join)
Thread.new do
assert pool.connection
pool.connection.close
end.join
end
# The connection pool is "fair" if threads waiting for
# connections receive them the order in which they began
# waiting. This ensures that we don't timeout one HTTP request
# even while well under capacity in a multi-threaded environment
# such as a Java servlet container.
#
# We don't need strict fairness: if two connections become
# available at the same time, it's fine of two threads that were
# waiting acquire the connections out of order.
#
# Thus this test prepares waiting threads and then trickles in
# available connections slowly, ensuring the wakeup order is
# correct in this case.
def test_checkout_fairness
@pool.instance_variable_set(:@size, 10)
expected = (1..@pool.size).to_a.freeze
# check out all connections so our threads start out waiting
conns = expected.map { @pool.checkout }
mutex = Mutex.new
order = []
errors = []
threads = expected.map do |i|
t = Thread.new {
begin
@pool.checkout # never checked back in
mutex.synchronize { order << i }
rescue => e
mutex.synchronize { errors << e }
end
}
Thread.pass until t.status == "sleep"
t
end
# this should wake up the waiting threads one by one in order
conns.each { |conn| @pool.checkin(conn); sleep 0.1 }
threads.each(&:join)
raise errors.first if errors.any?
assert_equal(expected, order)
end
# As mentioned in #test_checkout_fairness, we don't care about
# strict fairness. This test creates two groups of threads:
# group1 whose members all start waiting before any thread in
# group2. Enough connections are checked in to wakeup all
# group1 threads, and the fact that only group1 and no group2
# threads acquired a connection is enforced.
def test_checkout_fairness_by_group
@pool.instance_variable_set(:@size, 10)
# take all the connections
conns = (1..10).map { @pool.checkout }
mutex = Mutex.new
successes = [] # threads that successfully got a connection
errors = []
make_thread = proc do |i|
t = Thread.new {
begin
@pool.checkout # never checked back in
mutex.synchronize { successes << i }
rescue => e
mutex.synchronize { errors << e }
end
}
Thread.pass until t.status == "sleep"
t
end
# all group1 threads start waiting before any in group2
group1 = (1..5).map(&make_thread)
group2 = (6..10).map(&make_thread)
# checkin n connections back to the pool
checkin = proc do |n|
n.times do
c = conns.pop
@pool.checkin(c)
end
end
checkin.call(group1.size) # should wake up all group1
loop do
sleep 0.1
break if mutex.synchronize { (successes.size + errors.size) == group1.size }
end
winners = mutex.synchronize { successes.dup }
checkin.call(group2.size) # should wake up everyone remaining
group1.each(&:join)
group2.each(&:join)
assert_equal((1..group1.size).to_a, winners.sort)
if errors.any?
raise errors.first
end
end
def test_automatic_reconnect=
pool = ConnectionPool.new ActiveRecord::Base.connection_pool.spec
assert pool.automatic_reconnect
assert pool.connection
pool.disconnect!
assert pool.connection
pool.disconnect!
pool.automatic_reconnect = false
assert_raises(ConnectionNotEstablished) do
pool.connection
end
assert_raises(ConnectionNotEstablished) do
pool.with_connection
end
end
def test_pool_sets_connection_visitor
assert @pool.connection.visitor.is_a?(Arel::Visitors::ToSql)
end
end
end
end
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