* Added a version file and Tools->_anvil_version() which reports the version in it.

* Added Get->anvil_version() to check the local or remote Anvil! version.
* Added a check in Database->connect() to see if a database server's Anvil! version matches the local version. If the versions don't match, the database is not used.

Signed-off-by: Digimer <digimer@alteeve.ca>

Anvil/Tools.pm

@@ -24,6 +24,7 @@ my $THIS_FILE = "Tools.pm";
 # environment
 # nice_exit
 # _add_hash_reference
+# _anvil_version
 # _hostname
 # _make_hash_reference
 # _set_defaults
@@ -129,6 +130,7 @@ sub new
 		HOST				=>	{
 			# This is the host's UUID. It should never be manually set.
 			UUID			=>	"",
+			ANVIL_VERSION		=>	"",
 		},
 	};
 	
@@ -193,6 +195,9 @@ sub new
 	# Read in any command line switches.
 	$anvil->Get->switches;
 	
+	# Read in the local Anvil! version.
+
+	
 	# Set passed parameters if needed.
 	if (ref($parameter) eq "HASH")
 	{
@@ -505,6 +510,23 @@ sub _add_hash_reference
 	}
 }
 
+=head2 _anvil_version
+
+=cut
+sub _anvil_version
+{
+	my $self  = shift;
+	my $anvil = $self;
+	
+	if ($anvil->{HOST}{ANVIL_VERSION} eq "")
+	{
+		# Try to read the local Anvil! version.
+		$anvil->{HOST}{ANVIL_VERSION} = $anvil->Get->anvil_version();
+	}
+	
+	return($anvil->{HOST}{ANVIL_VERSION});
+}
+
 =head2 _hostname
 
 This returns the (full) hostname for the machine this is running on.
@@ -698,12 +720,13 @@ sub _set_paths
 	# Executables
 	$anvil->data->{path} = {
 			configs			=>	{
+				'anvil.conf'		=>	"/etc/anvil/anvil.conf",
+				'anvil.version'		=>	"/etc/anvil/anvil.version",
 				'firewalld.conf'	=>	"/etc/firewalld/firewalld.conf",
 				'journald_anvil'	=>	"/etc/systemd/journald.conf.d/anvil.conf",
 				'pg_hba.conf'		=>	"/var/lib/pgsql/data/pg_hba.conf",
 				'postgresql.conf'	=>	"/var/lib/pgsql/data/postgresql.conf",
 				ssh_config		=>	"/etc/ssh/ssh_config",
-				'anvil.conf'		=>	"/etc/anvil/anvil.conf",
 			},
 			data			=>	{
 				group			=>	"/etc/group",

Anvil/Tools/Database.pm

@@ -751,6 +751,31 @@ sub connect
 			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 3, list => { "sys::read_db_id" => $anvil->data->{sys}{read_db_id} }});
 		}
 		
+		# If this isn't a local database, read the target's Anvil! version (if available) and make 
+		# sure it matches ours. If it doesn't, skip this database.
+		if (not $is_local)
+		{
+			my $remote_version = $anvil->Get->anvil_version({
+				target   => $host,
+				password => $password,
+			});
+			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 2, list => { 
+				remote_version          => $remote_version, 
+				"anvil->_anvil_version" => $anvil->_anvil_version,
+			}});
+			
+			if ($remote_version ne $anvil->_anvil_version)
+			{
+				# Version doesn't match, 
+				$anvil->Log->entry({source => $THIS_FILE, line => __LINE__, level => 1, key => "log_0145", variables => { 
+					host           => $host,
+					local_version  => $anvil->_anvil_version, 
+					target_version => $remote_version,
+				}});
+				next;
+			}
+		}
+		
 		# Connect!
 		my $dbh = "";
 		### NOTE: The Database->write() method, when passed an array, will automatically disable 
@@ -853,6 +878,8 @@ sub connect
 				
 				if ($count < 1)
 				{
+					### TODO: Create a version file/flag and don't sync with peers unless
+					###       they are the same version. Back-port this to v2.
 					# Need to load the database.
 					$anvil->Database->initialize({id => $id, sql_file => $anvil->data->{path}{sql}{'anvil.sql'}});
 				}

Anvil/Tools/Get.pm

@@ -13,6 +13,7 @@ our $VERSION  = "3.0.0";
 my $THIS_FILE = "Get.pm";
 
 ### Methods;
+# anvil_version
 # cgi
 # date_and_time
 # host_uuid
@@ -86,6 +87,80 @@ sub parent
 # Public methods                                                                                            #
 #############################################################################################################
 
+=head2 anvil_version
+
+This reads to C<< VERSION >> file of a local or remote machine. If the version file isn't found, C<< 0 >> is returned. 
+
+Parameters;
+
+=head3 password (optional)
+
+This is the password to use when connecting to a remote machine. If not set, but C<< target >> is, an attempt to connect without a password will be made.
+
+=head3 port (optional)
+
+This is the TCP port to use when connecting to a remote machine. If not set, but C<< target >> is, C<< 22 >> will be used.
+
+=head3 target (optional)
+
+This is the IP or host name of the machine to read the version of. If this is not set, the local system's version is checked.
+
+=cut
+sub anvil_version
+{
+	my $self      = shift;
+	my $parameter = shift;
+	my $anvil     = $self->parent;
+	
+	my $debug    = $parameter->{debug}    ? $parameter->{debug}    : 2;
+	my $password = $parameter->{password} ? $parameter->{password} : "";
+	my $port     = $parameter->{port}     ? $parameter->{port}     : "";
+	my $target   = $parameter->{target}   ? $parameter->{target}   : "";
+	my $version  = 0;
+	$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => $debug, list => { 
+		password => $anvil->Log->secure ? $password : "--",
+		port     => $port, 
+		target   => $target, 
+	}});
+	
+	# Is this a local call or a remote call?
+	if (($target) && ($target ne "local") && ($target ne $anvil->_hostname) && ($target ne $anvil->_short_hostname))
+	{
+		# Remote call.
+		my $shell_call = "
+if [ -e ".$anvil->data->{path}{exe}{'anvil.version'}." ];
+then
+    cat ".$anvil->data->{path}{exe}{'anvil.version'}.";
+else
+   echo 0;
+fi;
+";
+		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => $debug, list => { shell_call => $shell_call }});
+		$version = $anvil->System->remote_call({
+			shell_call => $shell_call, 
+			target     => $target,
+			port       => $port, 
+			password   => $password,
+		});
+		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => $debug, list => { version => $version }});
+	}
+	else
+	{
+		# Local.
+		$version = $anvil->Storage->read_file({file => $anvil->data->{path}{exe}{'anvil.version'}});
+		$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => $debug, list => { version => $version }});
+		
+		# Did we actually read a version?
+		if ($version eq "!!error!!")
+		{
+			$version = 0;
+			$anvil->Log->variables({source => $THIS_FILE, line => __LINE__, level => 1, list => { version => $version }});
+		}
+	}
+	
+	return($version);
+}
+
 =head2 cgi
 
 This reads in the CGI variables passed in by a form or URL.

anvil.version

@@ -0,0 +1 @@
+3.0a

share/words.xml

@@ -215,6 +215,7 @@ The database connection error was:
 		<key name="log_0142"><![CDATA[[ Error ] - The system call: [#!variable!system_call!#] will fail because the program: [#!variable!program!#] isn't executable.]]></key>
 		<key name="log_0143">Failed to find a local ID, no databases are stored on this machine.</key>
 		<key name="log_0144">PostgreSQL server is not installed, unable to proceed.</key>
+		<key name="log_0145"><![CDATA[[ Warning ] - Unable to use the database on the host: [#!variable!host!#]. The local Anvil! version is: [#!variable!local_version!#], and the target host's is: [#!variable!target_version!#]. If you are upgrading, we will resync and use it once the host and our version is again the same.]]></key>
 		
 		<!-- Test words. Do NOT change unless you update 't/Words.t' or tests will needlessly fail. -->
 		<key name="t_0000">Test</key>