Sha256: 44f260bc93fa62fe21ce7ad3914db63db7f1da4c70bb8e466edf5f81daee37df
Contents?: true
Size: 919 Bytes
Versions: 8
Compression:
Stored size: 919 Bytes
Contents
require 'digest'
class TN::AdvisoryLock
def initialize(key, wait: false)
key = self.class.string_to_int(key) unless key.is_a?(Integer)
@key = key
@wait = wait
end
# Convert a string to a int that's needed for the advisory lock.
def self.string_to_int(string)
Digest::SHA1.hexdigest(string)[0..10].to_i(36)
end
def self.with_lock(key, wait: false)
result = nil
new(key, wait: wait).exclusive do
result = yield
end
result
end
def exclusive
if acquired?
begin
yield
ensure
release!
end
else
return false
end
true
end
private
def acquired?
TN.execute_sql("select #{sql_function}(#{@key})") != "f"
end
def sql_function
if @wait
"pg_advisory_lock"
else
"pg_try_advisory_lock"
end
end
def release!
TN.execute_sql("select pg_advisory_unlock(#{@key})")
end
end
Version data entries
8 entries across 8 versions & 1 rubygems