From: glyn Date: Sun, 26 Jun 2011 21:06:53 +0000 (+0100) Subject: Initial checkin X-Git-Url: https://git.8kb.co.uk/?a=commitdiff_plain;h=8bb56fec42d5dc92bceb83389d7b9bf8acb38061;p=slony-i%2Fpg_sched Initial checkin --- 8bb56fec42d5dc92bceb83389d7b9bf8acb38061 diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..fafff2e --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +.DS_Store +Thumbs.db diff --git a/LICENCE b/LICENCE new file mode 100644 index 0000000..94a9ed0 --- /dev/null +++ b/LICENCE @@ -0,0 +1,674 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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If your program is a subroutine library, you +may consider it more useful to permit linking proprietary applications with +the library. If this is what you want to do, use the GNU Lesser General +Public License instead of this License. But first, please read +. diff --git a/README.md b/README.md new file mode 100644 index 0000000..516bcc7 --- /dev/null +++ b/README.md @@ -0,0 +1,73 @@ +#PostgreSQL Scheduler + +Simple scheduler for running stored functions against databases in a +PostgreSQL cluster, with support for selective execution based on the +replication role of nodes in Slony-I clusters. + +The script is designed to be run once a minute from cron or similar, and +as such has a maximum resolution of 1 minute. It provides very simple +scheduling functionality to execute individual stored functions at +specified intervals and offsets (E.g. The most complex schedule would +be of the form "once every 5 hours at 20 minutes past the hour"). + +If you require more complex schedules or multi-step tasks try +pgAgent + +## Command line + +```bash +$ pg_sched.pl -h -p -d -U -n -t -cl -m -l + -h Hostname of database containing schedule table + DEFAULT = localhost + -p Listening port of database containing schedule table + DEFAULT = 5432 + -d Name of database containing schedule table + DEFAULT = postgres + -U User to connect to databse with, also used as default user for all tasks + DEFAULT = pg_sched + -n Name of schema containing schedule table + DEFAULT = public + -t Name of schedule table + DEFAULT = pg_sched + -cl Name of slony cluster. 'auto' to autodetect, 'off' to disable + DEFAULT = auto + -m Comma separated list of slony sets on the master. 'all' for all + DEFAULT = all + -l Lockfile used to prevent concurrent execution of tasks. + DEFAULT = not used +``` + +##Example usage + +Create a PostgreSQL user for schedule to run as, to run tasks under +different roles create the user as a superuser: + +```postgresql +mydb=> CREATE USER pg_sched WITH PASSWORD 'my_password' SUPERUSER ; +``` + +Create a pgpass file for the OS user that will run the script from cron: + +```bash +$ echo *:*:*:pg_sched:my_password >> /home/myuser/.pgpass +chmod 600 /home/myuser/.pgpass +``` + +Create the schedule table in your database of choice: + +```bash +$ psql -U pg_sched -d mydb -f pg_sched.sql +``` + +Add an entry to run from cron something like: + +```cron + * * * * * myuser /home/myuser/pg_sched.pl -d mydb -U pg_sched >> /var/log/pg_sched.log 2>&1 +``` + +Insert a row into the table to create a task, e.g: + +```postgresql +mydb=> INSERT INTO pg_sched (usename, datname, pronamespace, proname, proargs, proargtypes, enabled, frequency, frequency_offset) +VALUES ('test_user', 'mydb', 'pg_catalog', 'date_part', '{"hour", "2015-03-25 13:50:59"}', '{text, timestamp}', 'A', '1 hour', '1 minute'); +``` diff --git a/pg_sched.pl b/pg_sched.pl new file mode 100755 index 0000000..a62b7c0 --- /dev/null +++ b/pg_sched.pl @@ -0,0 +1,461 @@ +#!/usr/bin/perl + +# Script: pg_sched.pl +# Copyright: 26/06/2011: v1.0.0 Glyn Astill +# PostgreSQL 9.0+ (optional Slony-I) +# +# This script is a command-line utility to schedule execution of stored +# functions against databases in a PostgreSQL cluster, with support for +# selective execution based on the replication role of nodes in Slony-I +# clusters. +# +# The script is designed to be run from cron and has a maximum resolution +# of 1 minute. +# +# This script is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. +# +# This script is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this script. If not, see . + +use strict; +use warnings; +use threads; +use Time::HiRes qw/gettimeofday/; +use DBI; +use sigtrap 'handler' => \&cleanExit, 'HUP', 'INT','ABRT','QUIT','TERM'; +use Getopt::Long qw/GetOptions/; +Getopt::Long::Configure('no_ignore_case'); +use vars qw{%opt}; + +use constant false => 0; +use constant true => 1; + +my $g_slony_cluster = "test_replication"; +my $g_dbhost = 'localhost'; +my $g_dbport = 5432; +my $g_dbname = 'postgres'; +my $g_dbuser = 'pg_sched'; +my $g_dbschema = 'public'; +my $g_dbtable = 'pg_sched'; +my $g_clname = 'auto'; +my $g_sets = 'all'; +my $g_usage = "pg_sched.pl -h -p -d -U -n -t
-cl -m -l + -h Hostname of database containing schedule table + DEFAULT = $g_dbhost + -p Listening port of database containing schedule table + DEFAULT = $g_dbport + -d Name of database containing schedule table + DEFAULT = $g_dbname + -U User to connect to databse with, also used as default user for all tasks + DEFAULT = $g_dbuser + -n Name of schema containing schedule table + DEFAULT = $g_dbschema + -t Name of schedule table + DEFAULT = $g_dbtable + -cl Name of slony cluster. 'auto' to autodetect, 'off' to disable + DEFAULT = $g_clname + -m Comma separated list of slony sets on the master. 'all' for all + DEFAULT = $g_sets + -l Lockfile used to prevent concurrent execution of tasks. + DEFAULT = not used +"; + +my @g_databases; +my $g_origin = false; +my @g_pronames; +my $g_errors; +my $g_lockfile; + +die $g_usage unless GetOptions(\%opt, 'host|H=s', 'port|p=i', 'dbname|d=s', 'user|U=s', 'schema|n=s', 'table|t=s', 'lockfile|l=s', 'clname|cl=s', 'msets|m=s'); + +if (defined($opt{host})) { + $g_dbhost = $opt{host}; +} +if (defined($opt{port})) { + $g_dbport = $opt{port}; +} +if (defined($opt{dbname})) { + $g_dbname = $opt{dbname}; +} +if (defined($opt{user})) { + $g_dbuser = $opt{user}; +} +if (defined($opt{schema})) { + $g_dbschema = $opt{schema}; +} +if (defined($opt{table})) { + $g_dbtable = $opt{table}; +} +if (defined($opt{lockfile})) { + $g_lockfile = $opt{lockfile}; +} +if (defined($opt{clname})) { + $g_clname = $opt{clname}; +} +if (defined($opt{msets})) { + $g_sets = $opt{msets}; +} + +# If lockfile supplied check if the script is already running +if (defined($g_lockfile)) { + schedLock($g_lockfile, 'lock'); +} + +# Get a list of databases in the postgresql cluster +@g_databases = loadDatabases($g_dbhost, $g_dbport, $g_dbname, $g_dbuser); + +# For each database get its replication status then get any work to do +undef @g_pronames; +foreach my $target_dbname (@g_databases) { + if ($g_clname ne 'off') { + $g_origin = checkSlony($g_dbhost, $g_dbport, $target_dbname, $g_dbuser, $g_clname, $g_sets); + } + else { + $g_origin = true; + } + @g_pronames = (@g_pronames, loadWork($g_dbhost, $g_dbport, $g_dbname, $g_dbuser, $g_dbschema, $g_dbtable, $g_origin, $target_dbname)); +} +# Do all the work we have collected for all databases +$g_errors = doWork(\@g_pronames, $g_dbhost, $g_dbport, $g_dbname, $g_dbuser, $g_dbschema, $g_dbtable); + +if ($g_errors > 0) { + warn ("ERROR: Encountered $g_errors errors processing the schedule\n") if $@; +} + +cleanExit($g_lockfile); + +sub cleanExit{ + my $lockfile = shift; + + if (defined($lockfile)) { + schedLock($lockfile, 'unlock'); + } + exit(0); +} + +sub schedLock{ + my $lockdir = shift; + my $op = shift; + + if ($op eq 'lock') { + eval { + mkdir($lockdir) or die "Can't make directory: $!"; + }; + die ("Script already running") if $@; + } + else { + eval { + rmdir $lockdir; + }; + die ("unable to remove lock\n") if $@; + } +} + +sub loadDatabases{ + my $dbhost = shift; + my $dbport = shift; + my $dbname = shift; + my $dbuser = shift; + my $dsn; + my $dbh; + my $sth; + my $query; + my @databases; + + $dsn = "DBI:Pg:dbname=$dbname;host=$dbhost;port=$dbport;"; + eval { + $dbh = DBI->connect($dsn, $dbuser); + { + $dbh->do("SET application_name = 'pg_sched'"); + + $query = "SELECT datname FROM pg_catalog.pg_database WHERE datallowconn AND NOT datistemplate;"; + + $sth = $dbh->prepare($query); + $sth->execute(); + + while (my $databasename = $sth->fetchrow) { + push(@databases, $databasename); + } + } + }; + warn ("ERROR: Loading databaees failed\n") if $@; + + return @databases; +} + +sub checkSlony{ + my $dbhost = shift; + my $dbport = shift; + my $target_dbname = shift; + my $dbuser = shift; + my $clname = shift; + my $sets = shift; + my $qw_clname; + my $dsn; + my $dbh; + my $sth; + my $query; + my $local_sets; + my $all_sets; + my $run_master = false; + + $dsn = "DBI:Pg:dbname=$target_dbname;host=$dbhost;port=$dbport;"; + eval { + $dbh = DBI->connect($dsn, $dbuser); + { + $dbh->do("SET application_name = 'pg_sched'"); + + if ($clname ne 'auto') { + $query = "SELECT substr(n.nspname,2) FROM pg_catalog.pg_namespace n WHERE n.nspname = ?;"; + } + else { + $query = "SELECT substr(n.nspname,2) FROM pg_catalog.pg_class c JOIN pg_catalog.pg_namespace n ON c.relnamespace = n.oid + WHERE c.relname = 'sl_set' AND c.relkind = 'r' GROUP BY n.nspname;"; + } + + $sth = $dbh->prepare($query); + + if ($clname ne 'auto') { + $sth->bind_param(1, "_" . $clname); + } + + $sth->execute(); + $clname = $sth->fetchrow; + + if (defined($clname)) { + $qw_clname = $dbh->quote_identifier("_" . $clname); + + $query = "SELECT count(*), sum(CASE WHEN s.set_origin = $qw_clname.getlocalnodeid(?::name) THEN 1 ELSE 0 END) + FROM $qw_clname.sl_set s" . (($sets ne 'all')?' WHERE s.set_id = ANY(?::integer[]);':';'); + + $sth = $dbh->prepare($query); + $sth->bind_param(1, "_" . $clname); + if ($sets ne 'all') { + $sth->bind_param(2, [ split(',', $sets) ]); + } + + $sth->execute(); + + ($all_sets, $local_sets) = $sth->fetchrow; + + if (($all_sets // 0) == ($local_sets // 0)) { + $run_master = true; + } + else { + $run_master = false; + } + } + else { + $run_master = true; + } + } + }; + warn ("ERROR: Failed reading slony node config\n") if $@; + + return $run_master; +} + +sub loadWork{ + my $dbhost = shift; + my $dbport = shift; + my $dbname = shift; + my $dbuser = shift; + my $dbschema = shift; + my $dbtable = shift; + my $node_role = shift; + my $target_dbname = shift; + my $dsn; + my $dbh; + my $sth; + my $query; + my $qw_schedname; + my @pronames; + + if ($node_role ne 'D') { + $dsn = "DBI:Pg:dbname=$dbname;host=$dbhost;port=$dbport;"; + eval { + $dbh = DBI->connect($dsn, $dbuser); + { + $dbh->do("SET application_name = 'pg_sched'"); + + $qw_schedname = $dbh->quote_identifier($dbschema) . '.' . $dbh->quote_identifier($dbtable); + + $query = "SELECT p.id, p.datname, p.pronamespace, p.proname, p.proargs, p.proargtypes, COALESCE(p.usename,current_user), ?::text, p.running FROM $qw_schedname p + WHERE p.datname = ? AND (p.enabled = 'A' OR p.enabled = ?) + AND (p.last_run IS NULL OR + (date_trunc('m', current_timestamp)-date_trunc('m',p.last_run))::interval >= p.frequency) + AND (p.isloose OR + (extract(EPOCH FROM date_trunc('m', current_timestamp-coalesce(frequency_offset,'0s'::interval)))::integer + %extract(EPOCH FROM frequency)::integer) = 0);"; + + $sth = $dbh->prepare($query); + $sth->bind_param(1, ($node_role?'O':'R')); + $sth->bind_param(2, $target_dbname); + $sth->bind_param(3, ($node_role?'O':'R')); + $sth->execute(); + + while (my @prodef = $sth->fetchrow) { + push(@pronames, \@prodef); + } + } + }; + warn ("ERROR: Loading work failed\n") if $@; + } + + return @pronames; +} + +sub doWork{ + my $pronames = shift; + my $dbhost = shift; + my $dbport = shift; + my $dbname = shift; + my $dbuser = shift; + my $dbschema = shift; + my $dbtable = shift; + my @workers; + my @worker_result; + my $bad = 0; + + foreach my $prodef (@$pronames) { + my ($t) = threads->new(\&runWorker, $prodef, $dbhost, $dbport, $dbname, $dbuser, $dbschema, $dbtable); + push(@workers,$t); + } + foreach (@workers) { + @worker_result = $_->join; + if ($worker_result[0] == true) { + print("$worker_result[1] [SUCCEEDED]\n"); + } + else { + print("$worker_result[1] [FAILED]\n"); + $bad++; + } + } + return $bad; +} + +sub runWorker{ + my $prodef = shift; + my $dbhost = shift; + my $dbport = shift; + my $dbname = shift; + my $dbuser = shift; + my $dbschema = shift; + my $dbtable = shift; + + my $dsn; + my $dbh; + my $sth; + my $query; + my $qw_schedname; + my @result; + my $success; + my ($g_year, $g_month, $g_day, $g_hour, $g_min, $g_sec) = (localtime(time))[5,4,3,2,1,0]; + my $timestamp = sprintf ("%02d/%02d/%04d %02d:%02d:%02d", $g_day, $g_month+1, $g_year+1900, $g_hour, $g_min, $g_sec); + my $detail = $timestamp . " Schedule: $dbschema.$dbtable Task: id#@$prodef[0] @$prodef[1].@$prodef[2].@$prodef[3](" . + (defined(@$prodef[4])?join(', ',@{@$prodef[4]}):'') . ") Rep Role: @$prodef[7] User: @$prodef[6] Result: "; + my $typindex = 0; + my $start; + my $end; + + if (!defined(@$prodef[8]) || !kill(0, @$prodef[8])) { + eval { + + eval { + $dsn = "DBI:Pg:dbname=$dbname;host=$dbhost;port=$dbport;"; + $dbh = DBI->connect($dsn, $dbuser); + $dbh->do("SET application_name = 'pg_sched'"); + + $qw_schedname = $dbh->quote_identifier($dbschema) . '.' . $dbh->quote_identifier($dbtable); + + $query = "UPDATE $qw_schedname SET running = ? WHERE id = ?;"; + $sth = $dbh->prepare($query); + $sth->bind_param(1, $$); + $sth->bind_param(2, @$prodef[0]); + $sth->execute(); + $sth->finish; + $dbh->disconnect(); + }; + if ($@) { + warn ("WARNING: pre update of schedule failed\n"); + } + + $dsn = "DBI:Pg:dbname=@$prodef[1];host=$dbhost;port=$dbport;"; + $dbh = DBI->connect($dsn, $dbuser); + $dbh->do("SET application_name = 'pg_sched'"); + + $sth = $dbh->prepare("SET session_authorization = ?"); + $sth->bind_param(1, @$prodef[6]); + $sth->execute(); + + $query = "SELECT " . $dbh->quote_identifier(@$prodef[2]) . '.' . $dbh->quote_identifier(@$prodef[3]) . '('; + if (defined(@$prodef[4])) { + foreach my $arg (@{@$prodef[4]}) { + #$query = $query . ($typindex>0?',':'') . $dbh->quote($arg) . '::' . @{@$prodef[5]}[$typindex]; + $query .= ($typindex>0?',':'') . '?::' . @{@$prodef[5]}[$typindex]; + $typindex++; + } + } + $query .= ');'; + + $sth = $dbh->prepare($query); + + $typindex = 0; + if (defined(@$prodef[4])) { + foreach my $arg (@{@$prodef[4]}) { + $typindex++; + $sth->bind_param($typindex, $arg); + } + } + $start = gettimeofday(); + $sth->execute(); + $end = gettimeofday(); + + while (my @result = $sth->fetchrow) { + $success = true; + $detail .= ($result[0] // 'NULL') . ' (Timing: ' . sprintf("%.2f sec", $end-$start) . ')'; + } + $sth->finish; + $dbh->disconnect(); + + eval { + $dsn = "DBI:Pg:dbname=$dbname;host=$dbhost;port=$dbport;"; + $dbh = DBI->connect($dsn, $dbuser); + $dbh->do("SET application_name = 'pg_sched'"); + + $qw_schedname = $dbh->quote_identifier($dbschema) . '.' . $dbh->quote_identifier($dbtable); + + $query = "UPDATE $qw_schedname SET running = NULL, last_run = ?::timestamp WHERE id = ?;"; + $sth = $dbh->prepare($query); + $sth->bind_param(1, $timestamp); + $sth->bind_param(2, @$prodef[0]); + $sth->execute(); + $sth->finish; + $dbh->disconnect(); + }; + if ($@) { + warn ("WARNING: post update of schedule failed\n"); + } + }; + if ($@) { + $success = false; + $detail = $@; + warn ("WARNING: worker execution failed\n"); + } + } + else { + $success = false; + $detail .= 'already running PID ' . @$prodef[8]; + } + + return ($success, $detail); +} + diff --git a/pg_sched.sql b/pg_sched.sql new file mode 100644 index 0000000..b8fda5c --- /dev/null +++ b/pg_sched.sql @@ -0,0 +1,56 @@ +SET search_path=public; + +DROP TYPE IF EXISTS node_role CASCADE; +CREATE TYPE node_role AS ENUM ('O', 'R', 'A', 'D'); + +DROP TABLE IF EXISTS pg_sched CASCADE; +CREATE TABLE pg_sched +( + id bigserial NOT NULL PRIMARY KEY, + datname text NOT NULL, + proname text NOT NULL, + pronamespace text NOT NULL, + proargs text[], + proargtypes text[], + usename text, + frequency interval NOT NULL, + frequency_offset interval NOT NULL DEFAULT '0s', + last_run timestamp, + enabled node_role NULL DEFAULT 'O', + isexclusive boolean NOT NULL DEFAULT true, + isloose boolean NOT NULL DEFAULT true, + tag varchar(50), + running integer, + CONSTRAINT pg_sched_unique UNIQUE (datname, proname, pronamespace, proargs, proargtypes, frequency, frequency_offset, enabled), + CHECK (array_length(proargs,1) IS NOT DISTINCT FROM array_length(proargtypes,1)) +); + +CREATE OR REPLACE FUNCTION pg_sched_check_types() RETURNS TRIGGER AS +$BODY$ +BEGIN + IF EXISTS(SELECT 1 FROM unnest(NEW.proargtypes) a + LEFT JOIN pg_catalog.pg_type + ON pg_catalog.format_type(oid, NULL) = a + OR typname = a WHERE typname IS NULL) THEN + RAISE EXCEPTION 'Value for column "proargtypes" contains invalid types: %', NEW.proargtypes; + END IF; + RETURN NEW; +END; +$BODY$ +LANGUAGE plpgsql; + +REVOKE ALL ON pg_sched FROM public; +GRANT SELECT ON pg_sched TO public; + +CREATE TRIGGER pg_sched_check_types_trigger +BEFORE UPDATE OR INSERT ON pg_sched +FOR EACH ROW WHEN (NEW.proargtypes IS NOT NULL) +EXECUTE PROCEDURE pg_sched_check_types(); + +-- Superuser is required to run tasks under differing credentials +-- CREATE USER pg_sched WITH PASSWORD 'my password' SUPERUSER ; +-- ALTER TABLE pg_sched OWNER TO pg_sched; + +-- Example task +-- INSERT INTO pg_sched (usename, datname, pronamespace, proname, proargs, proargtypes, enabled, frequency, frequency_offset) +-- VALUES ('test_user', 'mydb', 'pg_catalog', 'date_part', '{"hour", "2015-03-25 13:50:59"}', '{text, timestamp}', 'A', '1 hour', '1 minute');