/lib/sonarpush/ Current File: //lib/sonarpush/SonarPush.pm
package SonarPush;

use strict;

use POSIX;
use Proc::Daemon;
use HTTP::Tiny;
use JSON::Tiny qw(decode_json encode_json);
use MIME::Base64;

use SonarPush::Globals;
use SonarPush::Providers::State;
use SonarPush::Providers::Hardware;
use SonarPush::Providers::Software;

=head1 NAME

SonarPush - Collects information/stats. 
   
=head1 DESCRIPTION

Class for starting/running sonarpush daemon and collecting data about various machine
attributes like software, hardware, states.  Once data is collected from the machine the 
daemon is running on it is posted to a central server (currently Mr.Radar) where it is stored. 

=head2 new 

=over 4

=item Description:

   my $sonarpush = SonarPush->new();

Initializes sonarpush object and creates a local datastructure of status attributes 
used to keep track of success/fail attempts when posting the collected data to 
the collection server. Provider objects are also initialized and stored in the local
$self->{providers} dataset which do the actual collection work. 

=item Parameters

none

=item Returns

A blessed class object with status attributes, and provider classes. 

=back

=cut

sub new {
	my $class = shift;

	my $self = {
		status => {
			Updates => {
				successful => 0,
				failed     => 0,
				total      => 0,
			},
			Checkins => {
				successful => 0,
				failed     => 0,
				total      => 0,
			},
		},
		providers => {},
	};
	bless $self, $class;
	map { $self->{providers}{$_} = "SonarPush::Providers::$_"->new($self) } qw(State Hardware Software);
	$self->{Started} = POSIX::strftime("%Y/%m/%d %H:%M:%S", localtime);

	return $self;
}

=head2 provider 

=over 4

=item Description:

$self->provider('Software'); 

Creates or returns a previously created provider object.  Each provider object contains methods used to collect data. 

$self->provider('Hardware')->cpu; 

=item Parameters

$provider: Software, Hardware, or State. 

=item Returns

the provider object specified as the parameter. 

=back

=cut

sub provider {
	my ($self, $provider) = @_;
	return $self->{providers}{$provider} ||= "SonarPush::Providers::$provider"->new($self);
}

=head2 userAgent 

=over 4

=item Description:

$self->userAgent; 

Creates or returns a previously created HTTP::Tiny UserAgent  object.


=item Parameters

none

=item Returns

HTTP::Tiny UserAgent  object

=back

=cut

sub userAgent {
	my $self    = shift;
	my $version = $self->version;

	$self->{useragent} ||= do {
		my $ua = HTTP::Tiny->new(
			agent    => $SonarPush::Globals::USERAGENT . $version,
			ssl_opts => { verify_hostname => 0, SSL_verify_mode => 0, },
			timeout  => $SonarPush::Globals::HTTP_TIMEOUT,
		);
		$ua;
	};
	return $self->{useragent};
}

=head2 post 

=over 4

=item Description:

$self->post($args); 

JSON encoded the passed parameters and submits a authenticated http post
of the encoded data.   

=item Parameters

url parameters to pass to webserver, see process and run method.  

=item Returns

returns a JSON encoded data returned by the webserver, either consisting of actual data, or error response codes. 

=back

=cut

sub post {
	my $self = shift;
	my $args = shift;

	my $json = encode_json($args);
	my $ua   = $self->userAgent;

	my $response = $ua->post_form($SonarPush::Globals::PUSH_URL,
		{ request => $json },
		{ headers => { Authorization => $self->authHeader } },
	);

	if ($response->{status} == 599) {
		$response->{error} .= "Error processing https request timeout [ $@ ]\n";
	}

	if (!($response->{success})) {
		$response->{error} .= "Error processing https request: " . $response->{reason} . "\n";
	}
	else {
		$self->printlog("Good POST\n");
		my $body = $response->{content};

		eval {
			$response = decode_json($body);
		};
		if ($@) {
			$response->{error} .= "Invalid JSON reponse received. $body\n";
		}
		else {
			if ($response->{'RequestResult'} eq "OK") {
				$self->printlog("Result = OK\n");
			}
			else {
				$response->{error} .= 'Error processing https request ' + $response->{'RequestResultMessage'} . "\n";
			}
		}
	}
	return $response;
}

=head2 run 

=over 4

=item Description:

$sonarpush->run() 

After $sonarpush->start has been called successfully run() puts the program
into an endless timed loop and processes schedule info every X seconds. 

=item Parameters

none 

=item Returns

undef 

=back

=cut

sub run {
	my $self = shift;
	my $args = shift;

	if (($< == 0) or ($> == 0) or ($( == 0) or ($) == 0)) {
		$self->suicide("Root privileges were not dropped properly.  Exiting!\n");
	}

	$self->{failcount} = 0;
	$self->{loopint}   = $SonarPush::Globals::DEFAULT_COLLECTION_LOOP;

	while (1) {
		$self->checkDebugFile;

		$0 = $self->name . " [getting schedule information]";
		$self->printlog("Getting schedule information\n");

		if ($self->{failcount} > 5) {
			$self->printlog("More than 5 Consecutive HTTP failures have taken place. Falling back to fail-safe LoopInterval.\n");
			$self->{loopint} = $SonarPush::Globals::DEFAULT_COLLECTION_LOOP;
		}

		$self->scheduler({ Command => 'getScheduleInfo' });

		$0 = $self->name . " [sleeping]";
		$self->printlog("Sleeping for $self->{loopint} seconds\n");
		sleep($self->{loopint});
	}

	return;
}

=head2 scheduler 

=over 4

=item Description:

$sonarpush->scheduler({ Command => 'getScheduleInfo' }) 

gets a list of tasks and passes those tasks to be processed. 
keeps track of failure/success counts when processing those requests.
also keeps track of http post success and failures. 

=item Parameters

{ Command => 'getScheduleInfo' }

=item Returns

$self

=back

=cut

sub scheduler {
	my $self    = shift;
	my $request = shift;

	$self->{status}{Checkins}{total}++;
	my $response = $self->post($request);
	if (!$response->{error}) {
		$self->{status}{Checkins}{successful}++;
		$self->process($response);
	}
	else {
		$self->{status}{Checkins}{failed}++;
		$self->{failcount}++;
		$self->printlog($response->{error}, 1);
	}
	return $self;
}

=head2 process

=over 4

=item Description:

$self->process($response); 

this method determines if colletion providers need to be executed or not, 

=item Parameters

The response to a successful $self->post({ Command => 'getScheduleInfo' }); 

=item Returns

$self

=back

=cut

sub process {
	my $self     = shift;
	my $response = shift;

	if ($response->{'NextTask'} > $response->{'LoopInterval'}) {
		$self->printlog(
			"NextTask ("
				. $response->{'NextTask'}
				. ") is larger than our Sonar-specified LoopInterval ("
				.
				$response->{'LoopInterval'} . "). Setting LoopInterval to Sonar-specified LoopInterval.\n"
		);
		$self->{loopint} = $response->{'LoopInterval'};
	}
	elsif ($response->{'NextTask'} < 5) {
		$self->printlog("NextTask (" . $response->{'NextTask'} . ") is less than 5 seconds away. Setting LoopInterval to 5 seconds.\n");
		$self->{loopint} = 5;
	}
	else {
		$self->printlog("Setting LoopInterval to make our next request coincide with NextTask.\n");
		$self->{loopint} = ($response->{'NextTask'} + 1);
	}

	if ($response->{'TasksWaiting'} eq "yes") {
		$0 = $self->name . " [collecting data]";
		$self->printlog("Performing collections for the following tasks: " . $response->{'TaskList'} . "\n");

		my $buffer = $self->_generateTaskXML($response->{TaskList});

		$0 = $self->name . " [submitting data]";
		$self->printlog("Submitting data.\n");

		$self->update({
				Command      => 'postcollecteddata',
				XMLdata      => $buffer,
				WorkTicketID => $response->{'WorkTicketID'},
		});
	}
	return $self;
}

=head2 update 

=over 4

=item Description:

	$self->update({ 
		Command      => 'postcollecteddata',
		XMLdata      => $buffer,
		WorkTicketID => $response->{'WorkTicketID'},
	});


this method posts xml encoded provider task data to be posted to the collector server. 
also keeps track fo successful/fail updates posted to the collection server. 

=item Parameters

Command => 'postcollecteddata
XMLdata => valid xml string, 
WorkTicketID => derived from scheduleinfo. 

=item Returns

$self

=back

=cut

sub update {
	my $self    = shift;
	my $request = shift;

	$self->{status}{Updates}{total}++;
	my $result = $self->post($request);
	if ($result->{error}) {
		$self->{failcount}++;
		$self->{status}{Updates}{failed}++;
		$self->printlog($result->{error}, 1);
	}
	else {
		$self->{failcount} = 0;
		$self->{status}{Updates}{successful}++;
	}
	return $self;
}

sub checkDebugFile {
	my ($self) = @_;
	if ((-f $SonarPush::Globals::DEBUGFLAGFILE) and !$self->{debug}) {
		$self->{debug} = 1;
		$self->printlog("DEBUGFLAGFILE found. Enabling debug mode.\n");
	}
	elsif ((!-f $SonarPush::Globals::DEBUGFLAGFILE) and ($self->{debug})) {
		$self->printlog("DEBUGFLAGFILE is gone and DEBUG is currently set. Disabling debug mode.\n");
		$self->{debug} = 0;
	}
}

=head2 start 

=over 4

=item Description:

$sonarpush->start($args); 

this method starts the program as a process and forks, sets appropriate perms on the process 
pid file,
 
=item Parameters

any options that may be passed to Proc::Daemon for process initialzation. 

=item Returns

nothing
 
=back

=cut

sub start {
	my $self = shift;
	my $args = shift;

	if ($args->{debug}) {
		$self->{debug} = delete $args->{debug};
		$self->printlog("Debug mode... staying in foreground.\n");
	}

	if (($> != 0) or ($< != 0)) {
		$self->suicide("This program requires root privileges.\n");
	}

	$0 = $self->name . " [starting up]";
	$self->printlog("SonarPush " . $self->version . " starting\n");

	$self->setProcessUser;

	my $daemon;
	if (!$self->{debug}) {

		$args->{pid_file}     = $SonarPush::Globals::PIDFile;
		$args->{child_STDERR} = "+>>$SonarPush::Globals::LOGFILEERROR";

		my $daemon = Proc::Daemon->new();

		$daemon->Init($args);

		$SIG{'HUP'} = sub {
			$self->handleHUP();
		};

		chown $self->{processuser}{uid}, $self->{processuser}{gid}, $SonarPush::Globals::PIDFile
			or $self->printlog("Warning: Could not change ownership on PID File!\n", 1);

		chmod 0664, $SonarPush::Globals::PIDFile
			or $self->printlog("Warning: Could not change permissions on PID File!\n", 1);

		chown $self->{processuser}{uid}, $self->{processuser}{gid}, $self->getlogfilename()
			or $self->printlog("Warning: Could not set permissions on log file!\n");
	}

	my $credentials = $self->_authCredentials;
	$credentials->{auth_user} || $self->suicide("Error loading UserName for push authentication. Exiting.\n");

	if (!$credentials->{auth_pass}) {
		$self->register;
	}
	$self->dropPrivs({
			uid => $self->{processuser}{uid},
			gid => $self->{processuser}{gid}
	});
	$self->run();

	exit(1);
}

=head2 setProcessUser 

=over 4

=item Description:

this method sets the UID of the running process to the user specified in Globals.pm, 

=item Parameters

none 

=item Returns

$self

=back

=cut

sub setProcessUser {
	my $self = shift;

	$self->{processuser} ||= do {
		(my $login, my $pass, my $newUID, my $newGID) = getpwnam($SonarPush::Globals::NonPrivUser)
			or $self->suicide("$SonarPush::Globals::NonPrivUser not in passwd file");
		($login, $pass) = undef;

		{
			uid => $newUID,
			gid => $newGID
		};
	};

	if (!$self->{processuser}{uid} || !$self->{processuser}{gid}) {
		$self->suicide("Error obtaining non privledged user information!\n");
	}
	return $self;
}

=head2 dropPrivs 

=over 4

=item Description:

this program is started with root privs, and this method drops those privs to the UID
that is derived in setProcessUser. 

=item Parameters

{ $uid => 112, gid => 115} 

=item Returns

$self

=back

=cut

sub dropPrivs {
	my $self = shift;
	my $args = shift;

	if ($args->{uid} == 0) {
		$self->suicide("New UID has root privileges. Exiting!\n");
	}

	if ($args->{gid} == 0) {
		$self->suicide("New GID has root privileges. Exiting!\n");
	}

	$self->printlog("UID (real/effective): $</$>\n");
	$self->printlog("GID (real/effective): $(/$)\n");
	$self->printlog("Dropping privileges...\n");

	$( = $args->{gid};
	$) = $args->{gid};

	$< = $args->{uid};
	$> = $args->{uid};

	$self->printlog("UID (real/effective): $</$>\n");
	$self->printlog("GID (real/effective): $(/$)\n");

	return $self;
}

=head2 register 

=over 4

=item Description:

before sonarpush can collect data it must register with the collection server, this method
will continuously try to register with the UNIQ_ID of the subaccnt until a success is received. 
A sucessful registration means the app was able to successfully download a password file and store it. 

=item Parameters

none 

=item Returns

$self

=back

=cut

sub register {
	my $self = shift;

	my $tryfail     = 1;
	my $regtries    = 0;
	my $maxregtries = 5;

	while (($regtries <= $maxregtries) and $tryfail) {
		$regtries++;
		$self->printlog("Attempting to perform registration with Sonar system (attempt $regtries of $maxregtries).\n");

		my %options = (
			headers => {
				Authorization => $self->authHeader($SonarPush::Globals::REGISTER_USER, $SonarPush::Globals::REGISTER_PASS),
				}
		);

		my $ua = $self->userAgent;
		my $res = $ua->get("$SonarPush::Globals::REGISTER_URL?uid=$self->{auth_user}", \%options);

		if (!($res->{success})) {

			# GET failed
			$self->printlog("Request failed: [ $res->{status} $res->{reason} ].\n", 1);
			$tryfail = 1;
		}
		else {
			my $body = $res->{content};

			# Creation: SUCCESS
			# Password: SUCCESS: tEXnZG4gKzZLpQYBl754JHnDYBHZa

			if ($body =~ /^Creation: SUCCESS$/m) {

				# Creation was good
				$self->printlog("Base registration successful.\n");

				if ($body =~ /^Password: SUCCESS: ([A-Za-z0-9]{24,32})$/m) {
					$self->printlog("Password successfully retrieved.\n");
					$tryfail = 0;

					my $success = $self->storeAuthPass($1);
					if (not $success) {
						$self->suicide("There was an error writing to the password file.\n");
					}
				}
				else {
					# Password retrieval failed
					$self->suicide("Password retrieval failed. Password will need to be configured manually.\n");
				}
			}
			else {
				# Server creation unsuccessful
				$self->printlog("Base registration unsuccessful.\n");
				$tryfail++;
			}
		}

		if ($tryfail) {
			my $sleeptime = 600 * $regtries;
			$self->printlog("Sleeping for $sleeptime before retry...\n", 1);
			sleep($sleeptime);
		}
	}
	return $self;
}

=head2 _deriveTaskList 

=over 4

=item Description:

this method orders tasks by the provider it belogs to derived from  the string of tasks returned by the collection server

=item Parameters

a comma seperated string of tasks to be executed, this is returned after a successful getScheduleInfo post. 

=item Returns

a hashref of key value pairs of provider => tasks: 

	{ 
		software => [apache, exim], 
		hardware => [cpu disk], 
		state => [network], 
	}


=back

=cut

sub _deriveTasklist {
	my $self     = shift;
	my $response = shift;

	my %tasks = map { $_ => 1 } split(/,/, $response);

	for my $alias (qw(EVERYTHING ALLSOFTWARE ALLSTATE ALLHARDWARE)) {
		if ($tasks{$alias}) {
			delete $tasks{$alias};
			for my $subTask (@{ $SonarPush::Globals::TaskList{$alias} }) {
				$tasks{$subTask} = 1;
			}
		}
	}

	my %taskData;
TASK: foreach my $task (sort keys %tasks) {
		foreach my $type (qw/software hardware state/) {
			for my $typeTask (@{ $SonarPush::Globals::TaskList{ 'ALL' . uc $type } }) {
				if ($typeTask eq $task) {
					$taskData{$type} ||= [];
					push(@{ $taskData{$type} }, $task);
					next TASK;
				}
			}
		}
	}
	return \%taskData;
}

=head2 _generateTaskXML

=over 4

=item Description:

executes the provider tasks, and creates a wellformed XML string. 

=item Parameters

a comma seperated string of tasks to be executed, this is returned after a successful getScheduleInfo post. 

=item Returns

an xml string

=back

=cut

sub _generateTaskXML {
	my $self     = shift;
	my $response = shift;

	my $providerAttrs = {
		providedby => 'NONE',
		datatype   => 'None',
	};

	# This particular line of raw XML isn't producible by the XML generator.
	# As such, we need to explicitly prepend it to the generated output.
	# This is the only case where we should need to write explicit XML
	my @buffer = ('<?xml version="1.0"?>');

	my $taskhash = $self->_deriveTasklist($response);

	my $dataNode = {
		name  => 'data',
		value => [],
	};

	foreach my $provider (sort keys %$taskhash) {
		my $providerNode = {
			name       => $provider,
			attributes => $providerAttrs,
			value      => [],
		};
		push(@{ $dataNode->{value} }, $providerNode);

		my $class = ucfirst($provider);
		foreach my $task (@{ $taskhash->{$provider} }) {
			$task =~ s/[^\w_]//g;
			push(@{ $providerNode->{value} }, $self->provider($class)->$task());
		}
	}

	push(@buffer, SonarPush::Providers::encodeXML({
				name => 'provider',
				value => [ { name => 'version', value => 'SonarPush ' . $self->version }, $dataNode ]
	}));

	return join("\n", @buffer);
}

sub _authCredentials {
	my $self = shift;

	return {
		auth_user => $self->authUsername,
		auth_pass => $self->authPassword,
	};
}

sub storeAuthPass {
	my $self      = shift;
	my $auth_pass = shift;

	my $success = 1;

	my $fh;
	open $fh, '>', $SonarPush::Globals::PASSWORD_FILE or $success = 0;
	if ($success) {
		print $fh $auth_pass;
		chown 0, 0, $SonarPush::Globals::PASSWORD_FILE;
		chmod 0600, $SonarPush::Globals::PASSWORD_FILE;
		$self->{auth_pass} = $auth_pass;
	}

	return $success;
}

sub authUsername {
	my $self = shift;

	my $username;
	$self->{auth_user} ||= do {
		my $flag = 1;
		my $input;

		{
			local $/;
			open(INPUT, "< $SonarPush::Globals::USERNAME_FILE") or $flag = 0;
			if ($flag) {
				$input = <INPUT>;
			}
		}

		if ($flag) {
			if ($input =~ /^([A-Za-z0-9]{1,32})\s+$/) {
				$username = $1;
			}
		}
		$username;
	};
	return $self->{auth_user};
}

sub name {
	my $self = shift;

	$self->{appname} ||= do {
		my $app = "SonarPush " . $self->version;
		$app;
	};
	return $self->{appname};
}

sub version {
	my $self = shift;

	my $version;
	$self->{version} ||= do {
		if (-e $SonarPush::Globals::VERSIONFILE) {
			if (-r $SonarPush::Globals::VERSIONFILE) {
				local $/;
				open(INPUT, "< $SonarPush::Globals::VERSIONFILE") or $self->suicide("Could not open version file: $!");
				$version = <INPUT>;
				close(INPUT);
			}
		}
		chomp $version;
		$version;
	};

	return $self->{version};
}

sub authPassword {
	my $self = shift;

	my $password;
	$self->{auth_pass} ||= do {
		my $flag = 1;
		my $input;

		if (-e $SonarPush::Globals::PASSWORD_FILE) {
			if (-r $SonarPush::Globals::PASSWORD_FILE) {

				# Password file exists and is readable
				local $/;
				open(INPUT, "< $SonarPush::Globals::PASSWORD_FILE") or $flag = 0;
				if ($flag) {
					$input = <INPUT>;
				}
			}
			else {
				#password file exists, but is not readable
				$self->suicide("Password file exists, but is not readable. Exiting.\n");
			}

			if ($flag and $input =~ /^([A-Za-z0-9]{1,32})\s*$/) {
				$password = $1;
			}
		}
		$password;
	};
	return $self->{auth_pass};
}

sub now {
	my $self = shift;
	my $now = POSIX::strftime("[%Y/%m/%d %H:%M:%S] ", localtime);

	return $now;
}

sub getlogfilename {
	my $self = shift;

	return $SonarPush::Globals::LOGFILEBASE . POSIX::strftime("%Y%m%d", localtime) . ".log";
}

sub suicide {
	my $self    = shift;
	my $message = shift;

	$self->printlog($message, 1);
	die $message;
}

sub printlog {
	my $self    = shift;
	my $message = shift;
	my $error   = shift;

	print $message;
	my $logfile = $error ? $SonarPush::Globals::LOGFILEERROR : $self->getlogfilename();
	if ($error or $self->{debug}) {
		open(my $file, '>>', $logfile);
		print $file $self->now() . $message;
	}
	return;
}

sub handleHUP {
	my $self = shift;

	print "Caught HUP signal... \n";
	print "Removing PID file $SonarPush::Globals::PIDFile... ";
	if (unlink $SonarPush::Globals::PIDFile) {
		print "success!\n";
	}
	else {
		print "failed!\n";
	}
	exit;
}

sub authHeader {
	my ($self, $authuser, $authpass) = @_;

	$authuser ||= $self->authUsername;
	$authpass ||= $self->authPassword;

	my $code = 'Basic ' . MIME::Base64::encode($authuser . ':' . $authpass);
	$code =~ s/\n$//;
	return $code;
}
1;