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=head1 NAME |
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|
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AnyEvent::MP::Global - some network-global services |
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|
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=head1 SYNOPSIS |
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|
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use AnyEvent::MP::Global; |
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|
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=head1 DESCRIPTION |
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|
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This module maintains a fully-meshed network between global nodes and |
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tries to have connections with all nodes in the network. |
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|
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It also manages named port groups - ports can register themselves in any |
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number of groups that will be available network-wide, which is great for |
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discovering services. |
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|
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Running it on one node will automatically run it on all nodes, although, |
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at the moment, the global service is started by default anyways. |
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|
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=head1 GLOBALS AND FUNCTIONS |
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|
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=over 4 |
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|
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=cut |
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|
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package AnyEvent::MP::Global; |
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|
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use common::sense; |
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use Carp (); |
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|
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use AnyEvent (); |
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use AnyEvent::Util (); |
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|
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use AnyEvent::MP; |
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use AnyEvent::MP::Kernel; |
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use AnyEvent::MP::Transport (); |
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|
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use base "Exporter"; |
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|
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our @EXPORT = qw( |
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grp_reg |
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grp_get |
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grp_mon |
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); |
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|
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$AnyEvent::MP::Kernel::WARN->(7, "starting global service."); |
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|
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############################################################################# |
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# node protocol parts for global nodes |
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|
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{ |
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package AnyEvent::MP::Kernel; |
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|
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# TODO: this is ugly, maybe this should go into MP::Kernel or a separate module #d# |
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|
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our %NODE; |
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our $NODE; |
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our $LISTENER; |
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|
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our $GLOBAL; |
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our $MASTER; |
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our $MASTER_MON; |
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our $MASTER_TIMER; |
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|
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our %GLOBAL_SLAVE; |
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|
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our %GLOBAL_DB; # global db |
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our %LOCAL_DBS; # local databases of other global nodes |
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our %LOCAL_DB; # this node database |
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|
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our $SRCNODE; |
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our %node_req; |
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|
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# only in global code |
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our %GLOBAL_MON; # monitors {family}{"" or key} |
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|
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sub other_globals() { |
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grep $_ ne $NODE && node_is_up $_, keys %{ $GLOBAL_DB{"'g"} } |
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} |
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|
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# broadcasts a message to all other global nodes |
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sub g_broadcast { |
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snd $_, @_ |
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for other_globals; |
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} |
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|
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sub g_mon_check { |
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warn "g_mon_check<@_>\n";#d# |
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|
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my %node = ( |
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%{ $GLOBAL_MON{$_[1]}{$_[2]} }, |
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%{ $GLOBAL_MON{$_[1]}{"" } }, |
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%{ $GLOBAL_MON{"" }{"" } }, |
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); |
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|
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snd $_ => g_chg1 => $_[1], $_[2], @_ > 2 ? $_[3] : () |
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for keys %node; |
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} |
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|
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# add/replace a key in the database |
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sub g_add($$$$) { |
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$LOCAL_DBS{$_[0]}{$_[1]}{$_[2]} = |
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$GLOBAL_DB {$_[1]}{$_[2]} = $_[3]; |
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|
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g_broadcast g_add => $_[1] => $_[2] => $_[3] |
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if exists $GLOBAL_SLAVE{$_[0]}; |
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|
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warn "g_add<@_>\n";#d# |
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&g_mon_check; |
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} |
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|
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# delete a key from the database |
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sub g_del($$$) { |
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delete $LOCAL_DBS{$_[0]}{$_[1]}{$_[2]}; |
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|
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g_broadcast g_del => $_[1] => $_[2] |
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if exists $GLOBAL_SLAVE{$_[0]}; |
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|
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delete $GLOBAL_DB{$_[1]}{$_[2]}; |
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|
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# check if other node maybe still has the key, then we don't delete, but add |
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for (values %LOCAL_DBS) { |
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if (exists $_->{$_[1]}{$_[2]}) { |
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$GLOBAL_DB{$_[1]}{$_[2]} = $_->{$_[1]}{$_[2]}; |
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last; |
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} |
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} |
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|
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warn "g_del<@_>\n";#d# |
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&g_mon_check; |
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} |
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|
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# delete all keys from a database |
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sub g_clr($) { |
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my ($node) = @_; |
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|
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my $db = $LOCAL_DBS{$node}; |
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while (my ($f, $k) = each %$db) { |
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g_del $node, $f => $_ |
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for keys %$k; |
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} |
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|
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delete $LOCAL_DBS{$node}; |
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} |
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|
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# set the whole (node-local) database - previous value must be empty |
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sub g_set($$) { |
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my ($node, $db) = @_; |
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|
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while (my ($f, $k) = each %$db) { |
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g_add $node, $f => $_ => delete $k->{$_} |
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for keys %$k; |
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} |
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} |
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|
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# gather node databases from slaves |
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|
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# other node wants to make us the master |
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$node_req{g_slave} = sub { |
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my ($db) = @_; |
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|
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my $node = $SRCNODE->{id}; |
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undef $GLOBAL_SLAVE{$node}; |
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g_set $node, $db; |
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}; |
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|
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$node_req{g_add} = sub { |
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&g_add ($SRCNODE->{id}, @_); |
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}; |
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|
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$node_req{g_del} = sub { |
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&g_del ($SRCNODE->{id}, @_); |
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}; |
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|
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$node_req{g_set} = sub { |
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g_set $SRCNODE->{id}, $_[0]; |
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}; |
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|
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$node_req{g_find} = sub { |
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my ($node) = @_; |
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|
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snd $SRCNODE->{id}, g_found => $node, $GLOBAL_DB{"'l"}{$node}; |
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}; |
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|
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# monitoring |
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|
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sub g_slave_disconnect($) { |
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my ($node) = @_; |
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|
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g_clr $node; |
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|
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if (my $mon = delete $GLOBAL_SLAVE{$node}) { |
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while (my ($f, $fv) = each %$mon) { |
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delete $GLOBAL_MON{$f}{$_} |
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for keys %$fv; |
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} |
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} |
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} |
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|
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# g_mon0 family key - stop monitoring |
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$node_req{g_mon0} = sub { |
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delete $GLOBAL_MON{$_[0]}{$_[1]}{$SRCNODE->{id}}; |
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delete $GLOBAL_SLAVE{$SRCNODE->{id}}{$_[0]}{$_[1]}; |
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}; |
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|
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# g_mon1 family key - start monitoring |
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$node_req{g_mon1} = sub { |
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undef $GLOBAL_SLAVE{$SRCNODE->{id}}{$_[0]}{$_[1]}; |
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undef $GLOBAL_MON{$_[0]}{$_[1]}{$SRCNODE->{id}}; |
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#d# generate lots of initial change requests, or one big? |
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|
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snd $SRCNODE->{id}, g_chg0 => $_[0], $_[1] |
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}; |
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|
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############################################################################# |
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# switch to global mode |
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|
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$GLOBAL = 1; |
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$MASTER = $NODE; |
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undef $GLOBAL_SLAVE{$NODE}; # we are our own master (and slave) |
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$LOCAL_DBS{$NODE} = { %LOCAL_DB }; |
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|
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# regularly try to connect to global nodes - maybe use seeding code? |
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$MASTER_TIMER = AE::timer 0, $AnyEvent::MP::Kernel::CONFIG->{monitor_timeout}, sub { |
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(add_node $_)->connect |
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for keys %{ $GLOBAL_DB{"'g"} }; |
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}; |
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|
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# instantly connect to other global nodes when we learn of them |
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# so we don't have to wait for the timer. |
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#TODO |
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# $GLOBAL_MON{"'g"}{""}{""} = sub { |
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# (add_node $_[1])->connect; |
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# }; |
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|
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# delete slaves on node-down |
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# clear slave db on node-down |
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$MASTER_MON = mon_nodes sub { |
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g_slave_disconnect $_[0] unless $_[1]; |
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}; |
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|
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# tell everybody who connects that we are a global node |
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push @AnyEvent::MP::Transport::HOOK_GREET, sub { |
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$_[0]{local_greeting}{global} = 1; |
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}; |
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|
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# connect from a global node |
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sub g_global_connect { |
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my ($node) = @_; |
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|
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# we need to set this currently, as to avoid race conditions |
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# because it takes a while until the other global node tells us it is global. |
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|
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undef $GLOBAL_DB{"'g"}{$node}; |
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undef $LOCAL_DBS{$node}{"'g"}{$node}; |
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|
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# global nodes send all local databases, merged, |
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# as their local database to global nodes |
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my %db; |
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|
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for (values %LOCAL_DBS) { |
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while (my ($f, $fv) = each %$_) { |
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while (my ($k, $kv) = each %$fv) { |
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$db{$f}{$k} = $kv; |
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} |
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} |
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} |
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|
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snd $node => g_set => \%db; |
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} |
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|
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# send our database to every global node that connects |
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push @AnyEvent::MP::Transport::HOOK_CONNECT, sub { |
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return unless $_[0]{remote_greeting}{global}; |
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|
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g_global_connect $_[0]{remote_node}; |
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}; |
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|
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# tell our master that we are global now |
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for (values %NODE) { |
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if ($_->{transport} && $_->{transport}{remote_greeting}{global}) { |
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snd $_->{id} => "g_global"; |
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g_global_connect $_->{id}; |
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} |
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} |
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|
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$node_req{g_global} = sub { |
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g_slave_disconnect $SRCNODE->{id}; |
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$SRCNODE->{transport}{remote_greeting}{global} = 1; |
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g_global_connect $SRCNODE->{id}; |
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}; |
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|
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#d#d disconnect everybody to bootstrap development grr |
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|
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# $_->transport_error # remove Self::transport_error |
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# for values %NODE; |
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|
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# now add us to the set of global nodes |
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ldb_set "'g" => $NODE => undef; |
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} |
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|
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=item $guard = grp_reg $group, $port |
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|
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Register the given (local!) port in the named global group C<$group>. |
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|
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The port will be unregistered automatically when the port is destroyed. |
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|
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When not called in void context, then a guard object will be returned that |
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will also cause the name to be unregistered when destroyed. |
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|
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=cut |
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|
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# register local port |
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sub grp_reg($$) { |
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my ($group, $port) = @_; |
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|
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port_is_local $port |
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or Carp::croak "AnyEvent::MP::Global::grp_reg can only be called for local ports, caught"; |
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|
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defined wantarray && AnyEvent::Util::guard { unregister ($port, $group) } |
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} |
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|
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=item $ports = grp_get $group |
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|
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Returns all the ports currently registered to the given group (as |
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read-only(!) array reference). When the group has no registered members, |
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return C<undef>. |
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|
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=cut |
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|
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sub grp_get($) { |
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} |
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|
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=item $guard = grp_mon $group, $callback->($ports, $add, $del) |
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|
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Installs a monitor on the given group. Each time there is a change it |
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will be called with the current group members as an arrayref as the |
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first argument. The second argument only contains ports added, the third |
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argument only ports removed. |
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|
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Unlike C<grp_get>, all three arguments will always be array-refs, even if |
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the array is empty. None of the arrays must be modified in any way. |
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|
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The first invocation will be with the first two arguments set to the |
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current members, as if all of them were just added, but only when the |
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group is actually non-empty. |
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|
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Optionally returns a guard object that uninstalls the watcher when it is |
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destroyed. |
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|
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=cut |
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|
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sub grp_mon($$) { |
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my ($grp, $cb) = @_; |
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} |
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|
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=back |
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|
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=head1 SEE ALSO |
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|
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L<AnyEvent::MP>. |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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|
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=cut |
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|
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1 |
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|
