File: //lib64/squid/log_db_daemon
#!/usr/bin/perl
use strict;
use warnings;
use DBI;
use English qw( -no_match_vars );
use Getopt::Long;
use Pod::Usage;
$|=1;
=pod
=head1 NAME
log_db_daemon - Database logging daemon for Squid
=head1 SYNOPSIS
log_db_daemon DSN [options]
=head1 DESCRIPTION
This program writes Squid access.log entries to a database.
Presently only accepts the B<squid> native format
=over 8
=item B<DSN>
Database DSN encoded as a path. This is sent as the access_log file path.
Sample configuration:
access_log daemon:/host/database/table/username/password squid
to leave a parameter unspecified use a double slash:
access_log daemon://database/table/username/password squid
Default "DBI:mysql:database=squid"
=item B<--debug>
Write debug messages to Squid stderr or cache.log
=back
=cut
# the first argument to this script is the log file path describing the DSN
my $log_file = shift;
# others may be options
my $debug = 0;
GetOptions(
'debug' => \$debug,
);
# utility routine to print messages on stderr (so they appear in cache log)
# without using warn, which would clutter the log with source line numbers
sub log_info {
my $msg = shift;
print STDERR "$msg\n";
}
# we use logfile to pass database access information to this script
# sample configuration:
# access_log daemon:/host/database/table/username/password squid
# to let a parmeter unspecified, e.g. the database host, use a double slash:
# access_log daemon://database/table/username/password squid
my ( $host, $database, $table, $user, $pass ) = $log_file =~ / \/(.*?)\/(.*?)\/(.*?)\/(.*?)\/(.*?) \z /xms;
if ( !$host ) {
$host = 'localhost';
log_info("Database host not specified. Using $host.");
}
if ( !$database ) {
$database = 'squid_log';
log_info("Database name not specified. Using $database.");
}
if ( !$table ) {
$table = 'access_log';
log_info("Table parameter not specified. Using $table.");
}
if ( !$user ) {
$user = 'squid';
log_info("User parameter not specified. Using $user.");
}
if ( !$pass ) {
log_info('No password specified. Connecting with NO password.');
}
# fields that we should have in the table
# Order here must match the order of fields in the Log format and parse() output array.
my @db_fields = qw(
id
time_since_epoch
time_response
ip_client
squid_request_status
http_status_code
http_reply_size
http_method
http_url
http_username
squid_hier_status
ip_server
http_mime_type
);
# perform db connection
my $dsn = "DBI:mysql:database=$database" . ($host ne "localhost" ? ":$host" : "");
my $dbh;
my $sth;
eval {
warn "Connecting... dsn='$dsn', username='$user', password='...'";
$dbh = DBI->connect($dsn, $user, $pass, { AutoCommit => 1, RaiseError => 1, PrintError => 1 });
};
if ($EVAL_ERROR) {
die "Cannot connect to database: $DBI::errstr";
}
# a simple test to assure the specified table exists
eval {
my $q = 'SELECT ' . join(',',@db_fields) . " FROM $table LIMIT 1";
my $sth = $dbh->prepare($q);
$sth->execute;
};
if ($EVAL_ERROR) {
# run a query to create the table of required syntax
my $create_query = 'CREATE TABLE ' . $table . ' (' .
" id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY," .
" time_since_epoch DECIMAL(15,3)," .
" time_response INTEGER," .
" ip_client CHAR(15)," .
" ip_server CHAR(15)," .
" http_status_code VARCHAR(10)," .
" http_reply_size INTEGER," .
" http_method VARCHAR(20)," .
" http_url TEXT," .
" http_username VARCHAR(20)," .
" http_mime_type VARCHAR(50)," .
" squid_request_status VARCHAR(50)," .
" squid_hier_status VARCHAR(20)" .
");" ;
$sth = $dbh->prepare($create_query);
$sth->execute;
# test again and fail hard if it is still broken.
eval {
my $q = 'SELECT ' . join(',',@db_fields) . " FROM $table LIMIT 1";
my $sth = $dbh->prepare($q);
$sth->execute;
};
if ($EVAL_ERROR) {
die "Error initializing database table: $EVAL_ERROR";
};
}
# test
# for better performance, prepare the statement at startup
eval {
my $q = "INSERT INTO $table (" . join(',',@db_fields) . ") VALUES(NULL" . ',?' x (scalar(@db_fields)-1) . ')';
#$sth = $dbh->prepare("INSERT INTO $table VALUES(NULL,?,?,?,?,?,?,?,?,?,?,?,?)");
$sth = $dbh->prepare($q);
};
if ($EVAL_ERROR) {
die "Error while preparing sql statement: $EVAL_ERROR";
}
sub parse($) {
my ($line) = @_;
my (@t) = $line =~ /^L(\d+\.\d+) *(\d+?) (.*?) (.*?)\/(\d+?) (\d+?) (.*?) (.*?) (.*?) (.*?)\/(.*?) (.*)$/;
}
# main loop
while (my $line = <>) {
chomp $line;
my $cmd = substr($line, 0, 1); # extract command byte
if ( $cmd eq 'L' ) {
my @log_entry = parse($line);
eval { # we catch db errors to avoid crashing squid in case something goes wrong...
$sth->execute(@log_entry) or die $sth->errstr
};
if ( $EVAL_ERROR ) { # leave a trace of the error in the logs
warn $EVAL_ERROR . " values=(" . join(', ', @log_entry) . ')';
}
}
}
$dbh->disconnect();
__END__
=pod
=head1 DESCRIPTION
This module exploits the new logfile daemon support available in squid 2.7 and 3.2 to store access log entries in a MySQL database.
=head1 CONFIGURATION
=head2 Squid configuration
=head3 access_log directive
The path to the access log file is used to provide the database connection parameters.
access_log daemon:/mysql_host:port/database/table/username/password squid
The 'daemon' prefix is mandatory and tells squid that the B<logfile_daemon> helper is to be used instead of the normal file logging.
The last parameter tells squid which log format to use when writing lines to the log daemon.
Presently B<squid> format is supported.
=over 4
=item mysql_host:port
Host where the mysql server is running. If left empty, 'localhost' is assumed.
=item database
Name of the database to connect to. If left empty, 'squid_log' is assumed.
=item table
Name of the database table where log lines are stored. If left empty, 'access_log' is assumed.
=item username
Username to use when connecting to the database. If left empty, 'squid' is assumed.
=item password
Password to use when connecting to the database. If left empty, no password is used.
=back
To leave all fields to their default values, you can use a single slash:
access_log daemon:/ squid
To specify only the database password, which by default is empty, you must leave unspecified all the other parameters by using null strings:
access_log daemon://///password squid
=head3 logfile_daemon directive
This is the current way of telling squid where the logfile daemon resides.
logfile_daemon /path/to/squid/libexec/logfile-daemon_mysql.pl
The script must be copied to the location specified in the directive.
=head2 Database configuration
Let's call the database 'squid_log' and the log table 'access_log'. The username and password for the db connection will be both 'squid'.
=head3 Database
Create the database:
CREATE DATABASE squid_log;
=head3 User
Create the user:
GRANT INSERT,SELECT,CREATE ON squid_log.* TO 'squid'@'localhost' IDENTIFIED BY 'squid';
FLUSH PRIVILEGES;
Note that only CREATE, INSERT and SELECT privileges are granted to the 'squid' user. This ensures that the logfile daemon script cannot change or modify the log entries.
=head3 Table
The Daemon will attempt to initialize this table if none exists when it starts.
The table created should look like:
CREATE TABLE access_log (
id INTEGER NOT NULL AUTO_INCREMENT PRIMARY KEY,
time_since_epoch DECIMAL(15,3),
time_response INTEGER,
ip_client CHAR(15),
ip_server CHAR(15),
http_status_code VARCHAR(10),
http_reply_size INTEGER,
http_method VARCHAR(20),
http_url TEXT,
http_username VARCHAR(20),
http_mime_type VARCHAR(50),
squid_hier_status VARCHAR(20),
squid_request_status VARCHAR(20)
);
=head1 VERSION INFORMATION
This document refers to C<log_db_daemon> script version 0.5.
The script has been developed and tested in the following environment:
=over 4
=item squid-2.7 Squid-3.2
=item mysql 5.0.26 and 5.1
=item perl 5.8.8
=item OpenSUSE 10.2
=back
=head1 DATA EXTRACTION
=head2 Sample queries.
=over 4
=item Clients accessing the cache
SELECT DISTINCT ip_client FROM access_log;
=item Number of request per day
SELECT
DATE(FROM_UNIXTIME(time_since_epoch)) AS date_day,
COUNT(*) AS num_of_requests
FROM access_log
GROUP BY 1
ORDER BY 1;
=item Request status count
To obtain the raw count of each request status:
SELECT squid_request_status, COUNT(*) AS n
FROM access_log
GROUP BY squid_request_status
ORDER BY 2 DESC;
To calculate the percentage of each request status:
SELECT
squid_request_status,
(COUNT(*)/(SELECT COUNT(*) FROM access_log)*100) AS percentage
FROM access_log
GROUP BY squid_request_status
ORDER BY 2 DESC;
To distinguish only between HITs and MISSes:
SELECT
'hits',
(SELECT COUNT(*)
FROM access_log
WHERE squid_request_status LIKE '%HIT%')
/
(SELECT COUNT(*) FROM access_log)*100
AS percentage
UNION
SELECT
'misses',
(SELECT COUNT(*)
FROM access_log
WHERE squid_request_status LIKE '%MISS%')
/
(SELECT COUNT(*) FROM access_log)*100
AS percentage;
=item Response time ranges
SELECT
'0..500',
COUNT(*)/(SELECT COUNT(*) FROM access_log)*100 AS percentage
FROM access_log
WHERE time_response >= 0 AND time_response < 500
UNION
SELECT
'500..1000',
COUNT(*)/(SELECT COUNT(*) FROM access_log)*100 AS percentage
FROM access_log
WHERE time_response >= 500 AND time_response < 1000
UNION
SELECT
'1000..2000',
COUNT(*)/(SELECT COUNT(*) FROM access_log)*100 AS percentage
FROM access_log
WHERE time_response >= 1000 AND time_response < 2000
UNION
SELECT
'>= 2000',
COUNT(*)/(SELECT COUNT(*) FROM access_log)*100 AS percentage
FROM access_log
WHERE time_response >= 2000;
=item Traffic by mime type
SELECT
http_mime_type,
SUM(http_reply_size) as total_bytes
FROM access_log
GROUP BY http_mime_type
ORDER BY 2 DESC;
=item Traffic by client
SELECT
ip_client,
SUM(http_reply_size) AS total_bytes
FROM access_log
GROUP BY 1
ORDER BY 2 DESC;
=back
=head2 Speed issues
The MyISAM storage engine is known to be faster than the InnoDB one, so although it doesn't support transactions and referential integrity, it might be more appropriate in this scenario. You might want to append "ENGINE=MYISAM" at the end of the table creation code in the above SQL script.
Indexes should be created according to the queries that are more frequently run. The DDL script only creates an implicit index for the primary key column.
=head1 TODO
=head2 Table cleanup
This script currently implements only the C<L> (i.e. "append a line to the log") command, therefore the log lines are never purged from the table. This approach has an obvious scalability problem.
One solution would be to implement e.g. the "rotate log" command in a way that would calculate some summary values, put them in a "summary table" and then delete the lines used to calculate those values.
Similar cleanup code could be implemented in an external script and run periodically independently from squid log commands.
=head2 Testing
This script has only been tested in low-volume scenarios (single client, less than 10 req/s). Tests in high volume environments could reveal performance bottlenecks and bugs.
=head1 AUTHOR
Marcello Romani, marcello.romani@libero.it
Amos Jeffries, amosjeffries@squid-cache.org
=head1 COPYRIGHT AND LICENSE
* Copyright (C) 1996-2016 The Squid Software Foundation and contributors
*
* Squid software is distributed under GPLv2+ license and includes
* contributions from numerous individuals and organizations.
* Please see the COPYING and CONTRIBUTORS files for details.
Copyright (C) 2008 by Marcello Romani
This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself, either Perl version 5.8.8 or,
at your option, any later version of Perl 5 you may have available.
=cut