1 package stemmaweb::Controller::Stemweb;
3 use namespace::autoclean;
4 use Encode qw/ decode_utf8 /;
11 BEGIN { extends 'Catalyst::Controller' }
13 ## TODO Move the /algorithms/available function to the Stemweb module
14 my $STEMWEB_BASE_URL = 'http://slinkola.users.cs.helsinki.fi';
18 stemmaweb::Controller::Stemweb - Client listener for Stemweb results
22 This is a client listener for the Stemweb API as implemented by the protocol defined at
23 L<https://docs.google.com/document/d/1aNYGAo1v1WPDZi6LXZ30FJSMJwF8RQPYbOkKqHdCZEc/pub>.
30 Content-Type: application/json
39 result: <error message> }
41 Used by the Stemweb server to notify us that one or more stemma graphs
42 has been calculated in response to an earlier request.
46 sub result :Local :Args(0) {
48 if( $c->request->method eq 'POST' ) {
49 # TODO: Verify the sender!
51 if( ref( $c->request->body ) eq 'File::Temp' ) {
52 # Read in the file and parse that.
53 $c->log->debug( "Request body is in a temp file" );
54 open( POSTDATA, $c->request->body )
55 or return _json_error( $c, 500, "Failed to open post data file" );
56 binmode( POSTDATA, ':utf8' );
57 # JSON should be all one line
58 my $pdata = <POSTDATA>;
62 $answer = from_json( $pdata );
64 return _json_error( $c, 400,
65 "Could not parse POST request '' $pdata '' as JSON: $@" );
68 $answer = from_json( $c->request->body );
70 $c->log->debug( "Received push notification from Stemweb: "
71 . to_json( $answer ) );
72 return _process_stemweb_result( $c, $answer );
74 return _json_error( $c, 403, 'Please use POST!' );
80 GET algorithms/available
82 Queries the Stemweb server for available stemma generation algorithms and their
83 parameters. Returns the JSON answer as obtained from Stemweb.
87 sub available :Local :Args(0) {
89 my $ua = LWP::UserAgent->new();
90 my $resp = $ua->get( $STEMWEB_BASE_URL . '/algorithms/available' );
91 if( $resp->is_success ) {
92 $c->stash->{'result'} = $resp->content;
94 $c->stash->{'result'} = '{}';
96 $c->forward('View::JSON');
101 GET stemweb/query/<jobid>
103 A backup method to query the stemweb server to check a particular job status.
104 Returns a result as in /stemweb/result above, but status can also be -1 to
105 indicate that the job is still running.
109 sub query :Local :Args(1) {
110 my( $self, $c, $jobid ) = @_;
111 my $ua = LWP::UserAgent->new();
112 my $resp = $ua->get( $STEMWEB_BASE_URL . "/algorithms/jobstatus/$jobid" );
113 if( $resp->is_success ) {
115 my $response = decode_utf8( $resp->content );
116 $c->log->debug( "Got a response from the server: $response" );
119 $answer = from_json( $response );
121 return _json_error( $c, 500,
122 "Could not parse stemweb response '' $response '' as JSON: $@" );
124 return _process_stemweb_result( $c, $answer );
125 } elsif( $resp->code == 500 && $resp->header('Client-Warning')
126 && $resp->header('Client-Warning') eq 'Internal response' ) {
127 # The server was unavailable.
128 return _json_error( $c, 503, "The Stemweb server is currently unreachable." );
130 return _json_error( $c, 500, "Stemweb error: " . $resp->code . " / "
136 ## Helper function for parsing Stemweb result data either by push or by pull
137 sub _process_stemweb_result {
138 my( $c, $answer ) = @_;
139 # Find the specified tradition and check its job ID.
140 my $m = $c->model('Directory');
141 my $tradition = $m->tradition( $answer->{textid} );
142 unless( $tradition ) {
143 return _json_error( $c, 400, "No tradition found with ID "
144 . $answer->{textid} );
146 if( $answer->{status} == 0 ) {
148 if( $tradition->has_stemweb_jobid
149 && $tradition->stemweb_jobid eq $answer->{jobid} ) {
151 $stemmata = $tradition->record_stemweb_result( $answer );
152 $m->save( $tradition );
153 } catch( Text::Tradition::Error $e ) {
154 return _json_error( $c, 500, $e->message );
156 return _json_error( $c, 500, $@ );
159 # It may be that we already received a callback meanwhile.
160 # Check all stemmata for the given jobid and return them.
161 @$stemmata = grep { $_->came_from_jobid && $_->from_jobid eq $answer->{jobid} } $tradition->stemmata;
165 # If we got here, success!
166 my @steminfo = map { {
167 name => $_->identifier,
168 directed => _json_bool( !$_->is_undirected ),
169 svg => $_->as_svg() } }
171 $c->stash->{'result'} = {
172 'status' => 'success',
173 'stemmata' => \@steminfo };
175 # Hm, no stemmata found on this tradition with this jobid.
176 # Clear the tradition jobid so that the user can try again.
177 if( $tradition->has_stemweb_jobid ) {
178 $tradition->_clear_stemweb_jobid;
179 $m->save( $tradition );
181 $c->stash->{'result'} = { status => 'notfound' };
183 } elsif( $answer->{status} < 1 ) {
184 $c->stash->{'result'} = { 'status' => 'running' };
186 return _json_error( $c, 500,
187 "Stemweb failure not handled: " . $answer->{result} );
189 $c->forward('View::JSON');
194 GET stemweb/request/?
195 tradition=<tradition ID> &
196 algorithm=<algorithm ID> &
197 [<algorithm parameters>]
199 Send a request for the given tradition with the given parameters to Stemweb.
200 Processes and returns the JSON response given by the Stemweb server.
204 sub request :Local :Args(0) {
205 my( $self, $c ) = @_;
206 # Look up the relevant tradition and check permissions.
207 my $reqparams = $c->req->params;
208 my $tid = delete $reqparams->{tradition};
209 my $t = $c->model('Directory')->tradition( $tid );
210 my $ok = _check_permission( $c, $t );
212 return( _json_error( $c, 403,
213 'You do not have permission to update stemmata for this tradition' ) )
214 unless $ok eq 'full';
216 # Form the request for Stemweb.
217 my $algorithm = delete $reqparams->{algorithm};
218 my $return_uri = URI->new( $c->uri_for( '/stemweb/result' ) );
219 my $stemweb_request = {
220 return_path => $return_uri->path,
221 return_host => $return_uri->host_port,
222 data => $t->collation->as_tsv({noac => 1}),
223 userid => $c->user->get_object->email,
225 parameters => $reqparams };
227 # Call to the appropriate URL with the request parameters.
228 my $ua = LWP::UserAgent->new();
229 $c->log->debug( 'Sending request to Stemweb: ' . to_json( $stemweb_request ) );
230 my $resp = $ua->post( $STEMWEB_BASE_URL . "/algorithms/process/$algorithm/",
231 'Content-Type' => 'application/json; charset=utf-8',
232 'Content' => encode_json( $stemweb_request ) );
233 if( $resp->is_success ) {
235 $c->log->debug( 'Got a response from the server: '
236 . decode_utf8( $resp->content ) );
237 my $stemweb_response = decode_json( $resp->content );
239 $t->set_stemweb_jobid( $stemweb_response->{jobid} );
240 } catch( Text::Tradition::Error $e ) {
241 return _json_error( $c, 429, $e->message );
243 $c->model('Directory')->save( $t );
244 $c->stash->{'result'} = $stemweb_response;
245 $c->forward('View::JSON');
246 } elsif( $resp->code == 500 && $resp->header('Client-Warning')
247 && $resp->header('Client-Warning') eq 'Internal response' ) {
248 # The server was unavailable.
249 return _json_error( $c, 503, "The Stemweb server is currently unreachable." );
251 return _json_error( $c, 500, "Stemweb error: " . $resp->code . " / "
256 # Helper to check what permission, if any, the active user has for
257 # the given tradition
258 sub _check_permission {
259 my( $c, $tradition ) = @_;
260 my $user = $c->user_exists ? $c->user->get_object : undef;
262 return 'full' if ( $user->is_admin ||
263 ( $tradition->has_user && $tradition->user->id eq $user->id ) );
265 # Text doesn't belong to us, so maybe it's public?
266 return 'readonly' if $tradition->public;
268 # ...nope. Forbidden!
269 return _json_error( $c, 403, 'You do not have permission to view this tradition.' );
272 # Helper to throw a JSON exception
274 my( $c, $code, $errmsg ) = @_;
275 $c->response->status( $code );
276 $c->stash->{'result'} = { 'error' => $errmsg };
277 $c->forward('View::JSON');
282 return $_[0] ? JSON::true : JSON::false;