chef/cookbooks/postgresql/libraries/default.rb
#
# Cookbook Name:: postgresql
# Library:: default
# Author:: David Crane (<davidc@donorschoose.org>)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
include Chef::Mixin::ShellOut
module Opscode
module PostgresqlHelpers
#######
# Function to truncate value to 4 significant bits, render human readable.
# Used in recipes/config_initdb.rb to set this attribute:
#
# The memory settings (shared_buffers, effective_cache_size, work_mem,
# maintenance_work_mem and wal_buffers) will be rounded down to keep
# the 4 most significant bits, so that SHOW will be likely to use a
# larger divisor. The output is actually a human readable string that
# ends with "GB", "MB" or "kB" if over 1023, exactly what Postgresql
# will expect in a postgresql.conf setting. The output may be up to
# 6.25% less than the original value because of the rounding.
def binaryround(value)
# Keep a multiplier which grows through powers of 1
multiplier = 1
# Truncate value to 4 most significant bits
while value >= 16
value = (value / 2).floor
multiplier = multiplier * 2
end
# Factor any remaining powers of 2 into the multiplier
while value == 2*((value / 2).floor)
value = (value / 2).floor
multiplier = multiplier * 2
end
# Factor enough powers of 2 back into the value to
# leave the multiplier as a power of 1024 that can
# be represented as units of "GB", "MB" or "kB".
if multiplier >= 1024*1024*1024
while multiplier > 1024*1024*1024
value = 2*value
multiplier = (multiplier/2).floor
end
multiplier = 1
units = "GB"
elsif multiplier >= 1024*1024
while multiplier > 1024*1024
value = 2*value
multiplier = (multiplier/2).floor
end
multiplier = 1
units = "MB"
elsif multiplier >= 1024
while multiplier > 1024
value = 2*value
multiplier = (multiplier/2).floor
end
multiplier = 1
units = "kB"
else
units = ""
end
# Now we can return a nice human readable string.
return "#{multiplier * value}#{units}"
end
#######
# Locale Configuration
# Function to test the date order.
# Used in recipes/config_initdb.rb to set this attribute:
# node.default['postgresql']['config']['datestyle']
def locale_date_order
# Test locale conversion of mon=11, day=22, year=33
testtime = DateTime.new(2033,11,22,0,0,0,"-00:00")
#=> #<DateTime: 2033-11-22T00:00:00-0000 ...>
# %x - Preferred representation for the date alone, no time
res = testtime.strftime("%x")
if res.nil?
return "mdy"
end
posM = res.index("11")
posD = res.index("22")
posY = res.index("33")
if (posM.nil? || posD.nil? || posY.nil?)
return "mdy"
elseif (posY < posM && posM < posD)
return "ymd"
elseif (posD < posM)
return "dmy"
else
return "mdy"
end
end
#######
# Timezone Configuration
require "find"
# Function to determine where the system stored shared timezone data.
# Used in recipes/config_initdb.rb to detemine where it should have
# select_default_timezone(tzdir) search.
def pg_TZDIR()
# System time zone conversions are controlled by a timezone data file
# identified through environment variables (TZ and TZDIR) and/or file
# and directory naming conventions specific to the Linux distribution.
# Each of these timezone names will have been loaded into the PostgreSQL
# pg_timezone_names view by the package maintainer.
#
# Instead of using the timezone name configured as the system default,
# the PostgreSQL server uses ones named in postgresql.conf settings
# (timezone and log_timezone). The initdb utility does initialize those
# settings to the timezone name that corresponds to the system default.
#
# The system's timezone name is actually a filename relative to the
# shared zoneinfo directory. That is usually /usr/share/zoneinfo, but
# it was /usr/lib/zoneinfo in older distributions and can be anywhere
# if specified by the environment variable TZDIR. The tzset(3) manpage
# seems to indicate the following precedence:
tzdir = nil
if ::File.directory?("/usr/lib/zoneinfo")
tzdir = "/usr/lib/zoneinfo"
else
share_path = [ENV["TZDIR"], "/usr/share/zoneinfo"].compact.first
if ::File.directory?(share_path)
tzdir = share_path
end
end
return tzdir
end
#######
# Function to support select_default_timezone(tzdir), which is
# used in recipes/config_initdb.rb.
def validate_zone(tzname)
# PostgreSQL does not support leap seconds, so this function tests
# the usual Linux tzname convention to avoid a misconfiguration.
# Assume that the tzdata package maintainer has kept all timezone
# data files with support for leap seconds is kept under the
# so-named "right/" subdir of the shared zoneinfo directory.
#
# The original PostgreSQL initdb is not Unix-specific, so it did a
# very complicated, thorough test in its pg_tz_acceptable() function
# that I could not begin to understand how to do in ruby :).
#
# Testing the tzname is good enough, since a misconfiguration
# will result in an immediate fatal error when the PostgreSQL
# service is started, with pgstartup.log messages such as:
# LOG: time zone "right/US/Eastern" appears to use leap seconds
# DETAIL: PostgreSQL does not support leap seconds.
if tzname.index("right/") == 0
return false
else
return true
end
end
# Function to support select_default_timezone(tzdir), which is
# used in recipes/config_initdb.rb.
def scan_available_timezones(tzdir)
# There should be an /etc/localtime zoneinfo file that is a link to
# (or a copy of) a timezone data file under tzdir, which should have
# been installed under the "share" directory by the tzdata package.
#
# The initdb utility determines which shared timezone file is being
# used as the system's default /etc/localtime. The timezone name is
# the timezone file path relative to the tzdir.
bestzonename = nil
if (tzdir.nil?)
Chef::Log.error("The zoneinfo directory not found (looked for /usr/share/zoneinfo and /usr/lib/zoneinfo)")
elsif !::File.exist?("/etc/localtime")
Chef::Log.error("The system zoneinfo file not found (looked for /etc/localtime)")
elsif ::File.directory?("/etc/localtime")
Chef::Log.error("The system zoneinfo file not found (/etc/localtime is a directory instead)")
elsif ::File.symlink?("/etc/localtime")
# PostgreSQL initdb doesn't use the symlink target, but this
# certainly will make sense to any system administrator. A full
# scan of the tzdir to find the shortest filename could result
# "US/Eastern" instead of "America/New_York" as bestzonename,
# in spite of what the sysadmin had specified in the symlink.
# (There are many duplicates under tzdir, with the same timezone
# content appearing as an average of 2-3 different file names.)
path = ::File.readlink("/etc/localtime")
bestzonename = path.gsub("#{tzdir}/","")
else # /etc/localtime is a file, so scan for it under tzdir
localtime_content = File.read("/etc/localtime")
Find.find(tzdir) do |path|
# Only consider files (skip directories or symlinks)
if !::File.directory?(path) && !::File.symlink?(path)
# Ignore any file named "posixrules" or "localtime"
if ::File.basename(path) != "posixrules" && ::File.basename(path) != "localtime"
# Do consider if content exactly matches /etc/localtime.
if localtime_content == File.read(path)
tzname = path.gsub("#{tzdir}/","")
if validate_zone(tzname)
if (bestzonename.nil? ||
tzname.length < bestzonename.length ||
(tzname.length == bestzonename.length &&
(tzname <=> bestzonename) < 0)
)
bestzonename = tzname
end
end
end
end
end
end
end
return bestzonename
end
# Function to support select_default_timezone(tzdir), which is
# used in recipes/config_initdb.rb.
def identify_system_timezone(tzdir)
resultbuf = scan_available_timezones(tzdir)
if !resultbuf.nil?
# Ignore Olson's rather silly "Factory" zone; use GMT instead
if (resultbuf <=> "Factory") == 0
resultbuf = nil
end
else
# Did not find the timezone. Fallback to use a GMT zone. Note that the
# Olson timezone database names the GMT-offset zones in POSIX style: plus
# is west of Greenwich.
testtime = DateTime.now
std_ofs = testtime.strftime("%:z").split(":")[0].to_i
resultbuf = [
"Etc/GMT",
(-std_ofs > 0) ? "+" : "",
(-std_ofs).to_s
].join("")
end
return resultbuf
end
#######
# Function to determine the name of the system's default timezone.
# Used in recipes/config_initdb.rb to set these attributes:
# node.default['postgresql']['config']['log_timezone']
# node.default['postgresql']['config']['timezone']
def select_default_timezone(tzdir)
system_timezone = nil
# Check TZ environment variable
tzname = ENV["TZ"]
if !tzname.nil? && !tzname.empty? && validate_zone(tzname)
system_timezone = tzname
else
# Nope, so try to identify system timezone from /etc/localtime
tzname = identify_system_timezone(tzdir)
if validate_zone(tzname)
system_timezone = tzname
end
end
return system_timezone
end
#######
# Function to determine the name of the system's default timezone.
def get_result_orig(query)
# query could be a String or an Array of String
if (query.is_a?(String))
stdin = query
else
stdin = query.join("\n")
end
@get_result ||= begin
cmd = shell_out("cat", input: stdin)
cmd.stdout
end
end
#######
# Function to execute an SQL statement in the template1 database.
# Input: Query could be a single String or an Array of String.
# Output: A String with |-separated columns and \n-separated rows.
# Note an empty output could mean psql couldn't connect.
# This is easiest for 1-field (1-row, 1-col) results, otherwise
# it will be complex to parse the results.
def execute_sql(query)
# query could be a String or an Array of String
statement = query.is_a?(String) ? query : query.join("\n")
@execute_sql ||= begin
cmd = shell_out("psql -q --tuples-only --no-align -d template1 -f -",
user: "postgres",
input: statement
)
# If psql fails, generally the postgresql service is down.
# Instead of aborting chef with a fatal error, let's just
# pass these non-zero exitstatus back as empty cmd.stdout.
if (cmd.exitstatus() == 0 and !cmd.stderr.empty?)
# An SQL failure is still a zero exitstatus, but then the
# stderr explains the error, so let's rais that as fatal.
Chef::Log.fatal("psql failed executing this SQL statement:\n#{statement}")
Chef::Log.fatal(cmd.stderr)
raise "SQL ERROR"
end
cmd.stdout.chomp
end
end
#######
# Function to determine if a standard contrib extension is already installed.
# Input: Extension name
# Output: true or false
# Best use as a not_if gate on bash "install-#{pg_ext}-extension" resource.
def extension_installed?(pg_ext)
@extension_installed ||= begin
installed=execute_sql("select 'installed' from pg_extension where extname = '#{pg_ext}';")
installed =~ /^installed$/
end
end
######################################
# Function to build information needed to install RPM for PGDG yum repository,
# since PGDG supports several versions of PostgreSQL, platforms, platform versions
# and architectures.
# Links to RPMs for installation are in an attribute so that new versions/platforms
# can be more easily added. (See attributes/default.rb)
def pgdgrepo_rpm_info
repo_rpm_url = node["postgresql"]["pgdg"]["repo_rpm_url"].
fetch(node["postgresql"]["version"]). # e.g., fetch for "9.1"
fetch(node["platform"]). # e.g., fetch for "centos"
fetch(node["platform_version"].to_f.to_i.to_s). # e.g., fetch for "5" (truncated "5.7")
fetch(node["kernel"]["machine"]) # e.g., fetch for "i386" or "x86_64"
# Extract the filename portion from the URL for the PGDG repository RPM.
# E.g., repo_rpm_filename = "pgdg-centos92-9.2-6.noarch.rpm"
repo_rpm_filename = File.basename(repo_rpm_url)
# Extract the package name from the URL for the PGDG repository RPM.
# E.g., repo_rpm_package = "pgdg-centos92"
repo_rpm_package = repo_rpm_filename.split(/-/,3)[0..1].join("-")
return [repo_rpm_url, repo_rpm_filename, repo_rpm_package]
end
# End the Opscode::PostgresqlHelpers module
end
end