Commit | Line | Data |
a9fdb55e |
1 | package Object::Remote::Role::Connector::PerlInterpreter; |
2 | |
55c0d020 |
3 | use IPC::Open3; |
4c8c83d7 |
4 | use IO::Handle; |
55c0d020 |
5 | use Symbol; |
5add5e29 |
6 | use Object::Remote::Logging qw(:log :dlog router); |
a9fdb55e |
7 | use Object::Remote::ModuleSender; |
8 | use Object::Remote::Handle; |
fbd3b8ec |
9 | use Object::Remote::Future; |
c824fdf3 |
10 | use Scalar::Util qw(blessed weaken); |
a9fdb55e |
11 | use Moo::Role; |
12 | |
13 | with 'Object::Remote::Role::Connector'; |
14 | |
03f41c0e |
15 | has module_sender => (is => 'lazy'); |
f1d70835 |
16 | has watchdog_timeout => ( is => 'ro', required => 1, default => sub { undef }); |
90f5193d |
17 | has forward_env => (is => 'ro', required => 1, builder => 1); |
f129bfaf |
18 | has perl_command => (is => 'lazy'); |
f1d70835 |
19 | has pid => (is => 'rwp'); |
20 | has connection_id => (is => 'rwp'); |
c824fdf3 |
21 | |
6b7b2732 |
22 | #if no child_stderr file handle is specified then stderr |
23 | #of the child will be connected to stderr of the parent |
c824fdf3 |
24 | has stderr => ( is => 'rw', default => sub { undef } ); |
03f41c0e |
25 | |
5add5e29 |
26 | BEGIN { router()->exclude_forwarding; } |
27 | |
03f41c0e |
28 | sub _build_module_sender { |
18e789ab |
29 | my ($hook) = |
30 | grep {blessed($_) && $_->isa('Object::Remote::ModuleLoader::Hook') } |
31 | @INC; |
03f41c0e |
32 | return $hook ? $hook->sender : Object::Remote::ModuleSender->new; |
33 | } |
34 | |
9cd7015d |
35 | #By policy object-remote does not invoke a shell |
37efeb68 |
36 | sub _build_perl_command { |
9cd7015d |
37 | my $perl_bin = 'perl'; |
55c0d020 |
38 | |
9cd7015d |
39 | if (exists $ENV{OBJECT_REMOTE_PERL_BIN}) { |
40 | $perl_bin = $ENV{OBJECT_REMOTE_PERL_BIN}; |
8f43bcd9 |
41 | } |
aaa31f6e |
42 | return [$perl_bin, '-']; |
37efeb68 |
43 | } |
498c4ad5 |
44 | |
90f5193d |
45 | sub _build_forward_env { |
46 | return [qw( |
47 | OBJECT_REMOTE_PERL_BIN |
48 | OBJECT_REMOTE_LOG_LEVEL OBJECT_REMOTE_LOG_FORMAT OBJECT_REMOTE_LOG_SELECTIONS |
49 | OBJECT_REMOTE_LOG_FORWARDING |
50 | )]; |
51 | } |
52 | |
03f41c0e |
53 | around connect => sub { |
54 | my ($orig, $self) = (shift, shift); |
fbd3b8ec |
55 | my $f = $self->$start::start($orig => @_); |
56 | return future { |
57 | $f->on_done(sub { |
58 | my ($conn) = $f->get; |
f1d70835 |
59 | $self->_setup_watchdog_reset($conn); |
60 | my $sub = $conn->remote_sub('Object::Remote::Logging::init_remote_logging'); |
f4a85080 |
61 | $sub->('Object::Remote::Logging', router => router(), connection_id => $conn->_id); |
fbd3b8ec |
62 | Object::Remote::Handle->new( |
63 | connection => $conn, |
64 | class => 'Object::Remote::ModuleLoader', |
65 | args => { module_sender => $self->module_sender } |
66 | )->disarm_free; |
67 | require Object::Remote::Prompt; |
68 | Object::Remote::Prompt::maybe_set_prompt_command_on($conn); |
69 | }); |
70 | $f; |
71 | } 2; |
a9fdb55e |
72 | }; |
73 | |
498c4ad5 |
74 | sub final_perl_command { shift->perl_command } |
a9fdb55e |
75 | |
7efea51f |
76 | sub _start_perl { |
a9fdb55e |
77 | my $self = shift; |
6b7b2732 |
78 | my $given_stderr = $self->stderr; |
79 | my $foreign_stderr; |
55c0d020 |
80 | |
088218cf |
81 | Dlog_verbose { |
82 | s/\n/ /g; "invoking connection to perl interpreter using command line: $_" |
83 | } @{$self->final_perl_command}; |
55c0d020 |
84 | |
6b7b2732 |
85 | if (defined($given_stderr)) { |
09130cd0 |
86 | #if the stderr data goes to an existing file handle |
87 | #an anonymous file handle is required |
88 | #as the other half of a pipe style file handle pair |
89 | #so the file handles can go into the run loop |
90 | $foreign_stderr = gensym(); |
6b7b2732 |
91 | } else { |
09130cd0 |
92 | #if no file handle has been specified |
93 | #for the child's stderr then connect |
94 | #the child stderr to the parent stderr |
95 | $foreign_stderr = ">&STDERR"; |
6b7b2732 |
96 | } |
55c0d020 |
97 | |
6b7b2732 |
98 | my $pid = open3( |
99 | my $foreign_stdin, |
100 | my $foreign_stdout, |
101 | $foreign_stderr, |
102 | @{$self->final_perl_command}, |
103 | ) or die "Failed to run perl at '$_[0]': $!"; |
55c0d020 |
104 | |
f1d70835 |
105 | $self->_set_pid($pid); |
55c0d020 |
106 | |
107 | if (defined($given_stderr)) { |
09130cd0 |
108 | Dlog_debug { "Child process STDERR is being handled via run loop" }; |
55c0d020 |
109 | |
09130cd0 |
110 | Object::Remote->current_loop |
111 | ->watch_io( |
112 | handle => $foreign_stderr, |
113 | on_read_ready => sub { |
55c0d020 |
114 | my $buf = ''; |
09130cd0 |
115 | my $len = sysread($foreign_stderr, $buf, 32768); |
116 | if (!defined($len) or $len == 0) { |
117 | log_trace { "Got EOF or error on child stderr, removing from watcher" }; |
118 | $self->stderr(undef); |
119 | Object::Remote->current_loop->unwatch_io( |
120 | handle => $foreign_stderr, |
121 | on_read_ready => 1 |
122 | ); |
6b7b2732 |
123 | } else { |
09130cd0 |
124 | Dlog_trace { "got $len characters of stderr data for connection" }; |
125 | print $given_stderr $buf or die "could not send stderr data: $!"; |
6b7b2732 |
126 | } |
55c0d020 |
127 | } |
128 | ); |
6b7b2732 |
129 | } |
55c0d020 |
130 | |
c824fdf3 |
131 | return ($foreign_stdin, $foreign_stdout, $pid); |
7efea51f |
132 | } |
133 | |
134 | sub _open2_for { |
135 | my $self = shift; |
136 | my ($foreign_stdin, $foreign_stdout, $pid) = $self->_start_perl(@_); |
fbd3b8ec |
137 | my $to_send = $self->fatnode_text; |
f1d70835 |
138 | log_debug { my $len = length($to_send); "Sending contents of fat node to remote node; size is '$len' characters" }; |
fbd3b8ec |
139 | Object::Remote->current_loop |
140 | ->watch_io( |
141 | handle => $foreign_stdin, |
142 | on_write_ready => sub { |
9031635d |
143 | my $len = syswrite($foreign_stdin, $to_send, 32768); |
fbd3b8ec |
144 | if (defined $len) { |
145 | substr($to_send, 0, $len) = ''; |
146 | } |
147 | # if the stdin went away, we'll never get Shere |
148 | # so it's not a big deal to simply give up on !defined |
353556c4 |
149 | if (!defined($len) or 0 == length($to_send)) { |
5d59cb98 |
150 | log_trace { "Got EOF or error when writing fatnode data to filehandle, unwatching it" }; |
fbd3b8ec |
151 | Object::Remote->current_loop |
152 | ->unwatch_io( |
153 | handle => $foreign_stdin, |
154 | on_write_ready => 1 |
09130cd0 |
155 | ); |
5d59cb98 |
156 | } else { |
157 | log_trace { "Sent $len bytes of fatnode data to remote side" }; |
fbd3b8ec |
158 | } |
159 | } |
160 | ); |
a9fdb55e |
161 | return ($foreign_stdin, $foreign_stdout, $pid); |
162 | } |
163 | |
c824fdf3 |
164 | sub _setup_watchdog_reset { |
09130cd0 |
165 | my ($self, $conn) = @_; |
55c0d020 |
166 | my $timer_id; |
167 | |
867e4de5 |
168 | return unless $self->watchdog_timeout; |
55c0d020 |
169 | |
09130cd0 |
170 | Dlog_trace { "Creating Watchdog management timer for connection id $_" } $conn->_id; |
55c0d020 |
171 | |
09130cd0 |
172 | weaken($conn); |
55c0d020 |
173 | |
09130cd0 |
174 | $timer_id = Object::Remote->current_loop->watch_time( |
175 | every => $self->watchdog_timeout / 3, |
176 | code => sub { |
177 | unless(defined($conn)) { |
867e4de5 |
178 | log_warn { "Weak reference to connection in Watchdog was lost, terminating update timer $timer_id" }; |
09130cd0 |
179 | Object::Remote->current_loop->unwatch_time($timer_id); |
867e4de5 |
180 | return; |
09130cd0 |
181 | } |
55c0d020 |
182 | |
867e4de5 |
183 | unless($conn->is_valid) { |
184 | log_warn { "Watchdog timer found an invalid connection, removing the timer" }; |
185 | Object::Remote->current_loop->unwatch_time($timer_id); |
186 | return; |
187 | } |
55c0d020 |
188 | |
09130cd0 |
189 | Dlog_trace { "Reseting Watchdog for connection id $_" } $conn->_id; |
190 | #we do not want to block in the run loop so send the |
191 | #update off and ignore any result, we don't need it |
192 | #anyway |
193 | $conn->send_class_call(0, 'Object::Remote::WatchDog', 'reset'); |
194 | } |
867e4de5 |
195 | ); |
55c0d020 |
196 | |
867e4de5 |
197 | $conn->on_close->on_ready(sub { |
198 | log_debug { "Removing watchdog for connection that is now closed" }; |
199 | Object::Remote->current_loop->unwatch_time($timer_id); |
200 | }); |
c824fdf3 |
201 | } |
202 | |
b1cbd5be |
203 | sub fatnode_text { |
204 | my ($self) = @_; |
8faf2a28 |
205 | my $connection_timeout = $self->timeout; |
206 | my $watchdog_timeout = $self->watchdog_timeout; |
b1cbd5be |
207 | my $text = ''; |
c824fdf3 |
208 | |
209 | require Object::Remote::FatNode; |
55c0d020 |
210 | |
8faf2a28 |
211 | if (defined($connection_timeout)) { |
212 | $text .= "alarm($connection_timeout);\n"; |
213 | } |
55c0d020 |
214 | |
8faf2a28 |
215 | if (defined($watchdog_timeout)) { |
f1d70835 |
216 | $text .= "my \$WATCHDOG_TIMEOUT = $watchdog_timeout;\n"; |
b7a853b3 |
217 | } else { |
8faf2a28 |
218 | $text .= "my \$WATCHDOG_TIMEOUT = undef;\n"; |
c824fdf3 |
219 | } |
55c0d020 |
220 | |
90f5193d |
221 | $text .= $self->_create_env_forward(@{$self->forward_env}); |
ffc9934e |
222 | |
223 | #Action at a distance but at least it's not spooky - the logging |
224 | #system needs to know if a node is remote but there is a period |
225 | #during init where the remote connection information has not been |
226 | #setup on the remote side yet so this flag allows a graceful |
227 | #degredation to happen |
f1d70835 |
228 | $text .= '$Object::Remote::FatNode::REMOTE_NODE = "1";' . "\n"; |
55c0d020 |
229 | |
b1cbd5be |
230 | $text .= <<'END'; |
231 | $INC{'Object/Remote/FatNode.pm'} = __FILE__; |
232 | $Object::Remote::FatNode::DATA = <<'ENDFAT'; |
233 | END |
fbd3b8ec |
234 | $text .= do { no warnings 'once'; $Object::Remote::FatNode::DATA }; |
b1cbd5be |
235 | $text .= "ENDFAT\n"; |
236 | $text .= <<'END'; |
237 | eval $Object::Remote::FatNode::DATA; |
1a2d795f |
238 | die $@ if $@; |
b1cbd5be |
239 | END |
55c0d020 |
240 | |
b1cbd5be |
241 | $text .= "__END__\n"; |
242 | return $text; |
243 | } |
244 | |
90f5193d |
245 | sub _create_env_forward { |
246 | my ($self, @env_names) = @_; |
247 | my $code = ''; |
248 | |
249 | foreach my $name (@env_names) { |
250 | next unless exists $ENV{$name}; |
251 | my $value = $ENV{$name}; |
252 | $name =~ s/'/\\'/g; |
253 | if(defined($value)) { |
254 | $value =~ s/'/\\'/g; |
255 | $value = "'$value'"; |
256 | } else { |
257 | $value = 'undef'; |
258 | } |
259 | $code .= "\$ENV{'$name'} = $value;\n"; |
260 | } |
261 | |
262 | return $code; |
263 | } |
264 | |
a9fdb55e |
265 | 1; |
de9062cf |
266 | |
267 | =head1 NAME |
268 | |
269 | Object::Remote::Role::Connector::PerlInterpreter - Role for connections to a Perl interpreter |
270 | |
271 | =head1 SYNOPSIS |
272 | |
273 | use Object::Remote; |
274 | |
275 | my %opts = ( |
276 | perl_command => [qw(nice -n 10 perl -)], |
277 | watchdog_timeout => 120, stderr => \*STDERR, |
278 | ); |
279 | |
280 | my $local_connection = Object::Remote->connect('-', %opts); |
281 | my $hostname = Sys::Hostname->can::on($remote, 'hostname'); |
282 | |
283 | =head1 DESCRIPTION |
284 | |
285 | This is the role that supports connections to a Perl interpreter that is executed in a |
286 | different process. The new Perl interpreter can be either on the local or a remote machine |
287 | and is configurable via arguments passed to the constructor. |
288 | |
289 | =head1 ARGUMENTS |
290 | |
291 | =over 4 |
292 | |
293 | =item perl_command |
294 | |
295 | By default the Perl interpeter will be executed as "perl -" but this can be changed by |
296 | providing an array reference as the value to the perl_command attribute during construction. |
297 | |
298 | =item stderr |
299 | |
300 | If this value is defined then it will be used as the file handle that receives the output |
301 | of STDERR from the Perl interpreter process and I/O will be performed by the run loop in a |
302 | non-blocking way. If the value is undefined then STDERR of the remote process will be connected |
303 | directly to STDERR of the local process with out the run loop managing I/O. The default value |
304 | is undefined. |
305 | |
306 | There are a few ways to use this feature. By default the behavior is to form one unified STDERR |
307 | across all of the Perl interpreters including the local one. For small scale and quick operation |
308 | this offers a predictable and easy to use way to get at error messages generated anywhere. If |
309 | the local Perl interpreter crashes then the remote Perl interpreters still have an active STDERR |
310 | and it is possible to still receive output from them. This is generally a good thing but can |
311 | cause issues. |
312 | |
313 | When using a file handle as the output for STDERR once the local Perl interpreter is no longer |
314 | running there is no longer a valid STDERR for the remote interpreters to send data to. This means |
315 | that it is no longer possible to receive error output from the remote interpreters and that the |
316 | shell will start to kill off the child processes. Passing a reference to STDERR for the local |
317 | interpreter (as the SYNOPSIS shows) causes the run loop to manage I/O, one unified STDERR for |
318 | all Perl interpreters that ends as soon as the local interpreter process does, and the shell will |
319 | start killing children when the local interpreter exits. |
320 | |
321 | It is also possible to pass in a file handle that has been opened for writing. This would be |
322 | useful for logging the output of the remote interpreter directly into a dedicated file. |
323 | |
324 | =item watchdog_timeout |
325 | |
326 | If this value is defined then it will be used as the number of seconds the watchdog will wait |
327 | for an update before it terminates the Perl interpreter process. The default value is undefined |
328 | and will not use the watchdog. See C<Object::Remote::Watchdog> for more information. |
329 | |
330 | =back |
331 | |
332 | =head1 SEE ALSO |
333 | |
334 | =over 4 |
335 | |
336 | =item C<Object::Remote> |
337 | |
338 | =back |
339 | |
340 | =cut |